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        <title>MathCity.org</title>
        <description>Merging man &amp; maths</description>
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            <title>MathCity.org</title>
            <link>https://www.mathcity.org/</link>
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        <item>
            <title>Mathematics 11 for FSc ICS (NBF)</title>
            <link>https://www.mathcity.org/math-11-nbf</link>
            <description>Mathematics 11 for FSc ICS (NBF)

[A Textbook of Mathematics for Class XI]
Model Textbook of Mathematics for Class XI is published by National Book Foundation (NBF), Islamabad, Pakistan. NBF can be considered as Federal Textbook Board Islamabad. The book has total of nine (9) chapters. This book is written by Dr. Khalid Mahmood, Dr. Saleem Ullah Satti, M Dabeer Mughal, Dr. Naveed Akmal and Dr. Shahzad Ahmad.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 14 Feb 2026 14:30:09 +0000</pubDate>
        </item>
        <item>
            <title>Mathematics 12 for FSc ICS (NBF)</title>
            <link>https://www.mathcity.org/math-12-nbf</link>
            <description>Mathematics 12 for FSc ICS (NBF)

[Textbook of Mathematics for Class 12]
Textbook of Mathematics for Class XII is published by National Book Foundation (NBF), Islamabad, Pakistan. NBF can be considered as Federal Textbook Board Islamabad. The book has total of ten (10) chapters. Dr, Khalid Mahmood is the Managing Author. Saleem Ullah Satti, Muhammad Dabeer Mughal, Dr. Naveed Akmal and Muhammad Anwar ul Haq are the co-authors of the book.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 16 Feb 2026 07:08:57 +0000</pubDate>
        </item>
        <item>
            <title>FSc</title>
            <link>https://www.mathcity.org/fsc</link>
            <description>FSc

Notes (Solutions), MCQs/Objective type questions, model papers and old/previous papers (of FBISE and BISE) given here, are useful for FSc Part 1 and Part 2 (HSSC). Text Book of Algebra and Trigonometry Class XI and Calculus and Analytic Geometry, MATHEMATICS 12, Punjab Text Book Board Lahore</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 26 May 2023 06:29:22 +0000</pubDate>
        </item>
        <item>
            <title>FSc Part 1 (Mathematics): KPK</title>
            <link>https://www.mathcity.org/fsc-part1-kpk</link>
            <description>FSc Part 1 (Mathematics): KPK

[A Textbook of Mathematics for Class XI]
A Textbook of Mathematics for Class XI is published by Khybar Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan. The book has total of twelve (12) chapters. This book is written by Prof. Dr. Gulzar Ali Khan, Prof. Dr. Islam Noor and Prof. Dr. Muhammad Shah.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 12 Dec 2023 17:09:07 +0000</pubDate>
        </item>
        <item>
            <title>FSc/ICS Part 1 (Mathematics): KPK</title>
            <link>https://www.mathcity.org/math-11-kpk</link>
            <description>FSc/ICS Part 1 (Mathematics): KPK

[A Textbook of Mathematics for Class XI]
A Textbook of Mathematics for Class XI is published by Khybar Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan. The book has total of twelve (12) chapters. This book is written by Prof. Dr. Gulzar Ali Khan, Prof. Dr. Islam Noor and Prof. Dr. Muhammad Shah.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 06 Feb 2024 13:20:19 +0000</pubDate>
        </item>
        <item>
            <title>MCQs/Objective: HSSC-I</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_mcqs</link>
            <description>MCQs/Objective: HSSC-I


Short Questions by Mr. Akhtar Abbas NEW 
Short Questions without answers by Mr. Akhtar Abbas for FSc Part 1.

MCQs-Short Questions by Mr Parvez Khan 
MCQs and Short Question by Mr. Parvez Khan composed by Momin Ali: Text Book of Algebra and Trigonometry Class XI (Punjab Textbook Board, Lahore)

MCQs by Nauman Idrees</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 02 May 2024 17:05:13 +0000</pubDate>
        </item>
        <item>
            <title>FSc/ICS Part 1 (Mathematics): PTB</title>
            <link>https://www.mathcity.org/fsc-part1-ptb</link>
            <description>FSc/ICS Part 1 (Mathematics): PTB
This is an old book. Notes of new book are available at following URL: &lt;https://www.mathcity.org/math-11-pectaa&gt;

[Textbook of Algebra and Trigonometry Class XI]
Textbook of Algebra and Trigonometry Class XI is published by Punjab Textbook Board (PTB) Lahore, Pakistan. The book has total of 14 chapters.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 19 Jul 2025 17:19:20 +0000</pubDate>
        </item>
        <item>
            <title>MCQs/Objective: HSSC-II</title>
            <link>https://www.mathcity.org/fsc/fsc_part_2_mcqs</link>
            <description>MCQs/Objective: HSSC-II

On this page, MCQ/Objective for FSc-II (HSSC-II) or FSc Part 2 are given.



	*  Objective Mathematics 12th by Muhammad Shahbaz NEW
		*  Short Questions without answers by Mr. Akhtar Abbas for FSc Part 2.






	*  Short Questions by Mr. Akhtar Abbas
		*  Short Questions without answers by Mr. Akhtar Abbas for FSc Part 2.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 21 Mar 2025 15:21:10 +0000</pubDate>
        </item>
        <item>
            <title>Exercise 1.1 (Solutions)</title>
            <link>https://www.mathcity.org/fsc-part1-ptb/sol/ch01/ex1-1</link>
            <description>Exercise 1.1 (Solutions)
Notes (Solutions) of Exercise 1.1: Textbook of Algebra and Trigonometry Class XI (Mathematics FSc Part 1 or HSSC-I), Punjab Textbook Board (PTB) Lahore.
The main topics of this exercise are properties of real numbers, binary operation, addition and multiplication law, properties of equality, properties of inequality (order properties), field, rule of fractions. These notes are based on the new Student Learning Outcomes (SLOs). Version: 4.0, Available at MathCity.org $\{0…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 13 Apr 2023 09:34:48 +0000</pubDate>
        </item>
        <item>
            <title>Exercise 2.8 (Solutions)</title>
            <link>https://www.mathcity.org/fsc-part1-ptb/sol/ch02/ex2-8</link>
            <description>Exercise 2.8 (Solutions)
Notes (Solutions) of Exercise 2.8: Textbook of Algebra and Trigonometry Class XI (Mathematics FSc Part 1 or HSSC-I), Punjab Textbook Board (PTB) Lahore.
The main topic of this exercise are binary operation, semi-group, monoid, groups and abelian groups. These notes are based on the new Student Learning Outcomes (SLOs). Version: 4.1, Available at MathCity.org $\oplus$$G=\{0,1\}$\[
\begin{array}{|c|c|c|}
\hline
  \oplus &amp; 0 &amp; 1 \\ 
\hline
   0 &amp; 1 &amp; 1 \\
\hline
   1 &amp; 1 &amp; …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 05 Apr 2023 12:55:15 +0000</pubDate>
        </item>
        <item>
            <title>Question 9, Exercise 1.4</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-4-p10</link>
            <description>Question 9, Exercise 1.4

Solutions of Question 9 of Exercise 1.4 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 9(i)
$x=2+3 i$$x_{\max }=1+4 i$$\mathrm{t}=0$$$x=2+3i$$$$x_{\max}=1+4 i$$$$\implies x=x_{\max} e^{i\theta}$$$$2+3i=(1+4 i) e^{i\theta}$$\begin{align}
\implies e^{i\theta}&amp;=\dfrac{2+3i}{1+4i} \\
&amp;=\dfrac{(2+3i)(1-4i)}{(1+4i)(1-4i)} \\
&amp;=\dfrac{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 17 Jul 2024 12:46:32 +0000</pubDate>
        </item>
        <item>
            <title>Mathematics 11 (PECTAA)</title>
            <link>https://www.mathcity.org/math-11-pectaa</link>
            <description>Mathematics 11 (PECTAA)

[Mathematics 11 for FSc and ICS (PECTAA)]
Mathematics 11 is is based on Updated/Revised National Curriculum of Pakistan 2023 and has been approved by the Punjab Education, Curriculum, Training and Assessment Authority (PECTAA) previously known as Punjab Textbook Board (PTB).  This is a textbook for all the boards of Punjab for 11th class (FSc or ICS Part 1 or HSSC-I). The book has total of fourteen (14) units.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 20 Jul 2025 06:50:20 +0000</pubDate>
        </item>
        <item>
            <title>FSc (Kyber Pakhtunkhwa (KPK) Boards)</title>
            <link>https://www.mathcity.org/fsc/kpk</link>
            <description>FSc (Kyber Pakhtunkhwa (KPK) Boards)

Notes (resources) Textbook of Mathematics for Class XI“ and “Textbook of Mathematics Grade 12” published by Khyber Pakhtunkhwa Textbook Board, Peshawar, Pakistan are available on this page. At the moment we are going to publish notes of FSc Part 1 and Part 2.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:42:51 +0000</pubDate>
        </item>
        <item>
            <title>FSc Part 2 (KPK Boards)</title>
            <link>https://www.mathcity.org/fsc/kpk_fsc_part_2</link>
            <description>FSc Part 2 (KPK Boards)

[A Textbook of Mathematics For Class XII]
Notes of FSc Part 2 of “A Textbook of Mathematics For Class XII” published by Khyber Pakhtunkhwa Textbook Board, Peshawar. We are posting the notes chapter-wise. These notes are shared as open educational resources. This page will be continuously updated.$y=x^n$$y=(ax+b)^n$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:42:52 +0000</pubDate>
        </item>
        <item>
            <title>Solutions: Math 11 KPK</title>
            <link>https://www.mathcity.org/math-11-kpk/sol</link>
            <description>Solutions: Math 11 KPK

[Solutions of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa]
Solutions of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.
Federal Board of Intermediate and Secondary Education (FBISE), Islamabad has been introduced Students Learning Outcomes (SLOs) Based Examination. Its complete scheme of studies is available on the FBISE website</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:03 +0000</pubDate>
        </item>
        <item>
            <title>Solutions: Math 11 NBF</title>
            <link>https://www.mathcity.org/math-11-nbf/sol</link>
            <description>Solutions: Math 11 NBF

[Solutions of Model Textbook of Mathematics for Class XI]
Solutions of Model Textbook of Mathematics for Class XI is published by National Book Foundation (NBF), Islamabad, Pakistan. NBF can be considered as Federal Textbook Board Islamabad. 
Federal Board of Intermediate and Secondary Education (FBISE), Islamabad has been introduced Students Learning Outcomes (SLOs) Based Examination. Its complete scheme of studies is available on the FBISE website</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 01 Feb 2025 19:18:00 +0000</pubDate>
        </item>
        <item>
            <title>Solutions: Math 12 NBF</title>
            <link>https://www.mathcity.org/math-12-nbf/sol</link>
            <description>Solutions: Math 12 NBF

[Solutions of Textbook of Mathematics 12]
Solutions of “Textbook of Mathematics 12 published by National Book Foundation (NBF), Islamabad, Pakistan”. NBF can be considered as Federal Textbook Board Islamabad. 
This comprehensive guide, Solutions for Mathematics 12, serves as a definitive resource for students mastering the advanced HSSC curriculum. Published by the National Book Foundation (NBF), it bridges the gap between complex theory and practical application. The tex…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 04 May 2026 16:11:21 +0000</pubDate>
        </item>
        <item>
            <title>Mathematics 9th for Matric (PCTB)</title>
            <link>https://www.mathcity.org/math-9th-pctb</link>
            <description>Mathematics 9th for Matric (PCTB)

[Mathematics 9th for Matric (PCTB)]
Mathematics 9 is published by Punjab Curriculum and Textbook Board (PCTB), Lahore, Pakistan. This is a textbook for all the boards of Punjab for matriculation. The book has total of thirteen (13) chapters. The book is written by Muhammad Akhtar Shirani (Senior Subject Specialist, Mathematics), Madiha Mehmood, (Subject Specialist, Statistics) and Ghulam Murtaza (Subject Specialist, Mathematics).</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 04 May 2026 16:19:23 +0000</pubDate>
        </item>
        <item>
            <title>Definitions: FSc Part1 KPK</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/definitions</link>
            <description>Definitions: FSc Part1 KPK

A Textbook of Mathematics for Class XI is published by Khybar Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan. The book has total of twelve (12) chapters.

Definition of the book provide the quick overview of the book.$360^\circ$$\theta$$90^{\circ} \pm \theta, 180^{\circ} \pm \theta, 270^{\circ} \pm \theta, 360^{\circ} \pm \theta$$16^\circ 13&#039; 9&#039;&#039;$$sin(\alpha+2\pi)=sin\alpha$$sin x=\frac{2}{7}$$cos x-tan x=0$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 28 Aug 2023 16:59:59 +0000</pubDate>
        </item>
        <item>
            <title>Definitions: FSc Part 1 (Mathematics): PTB</title>
            <link>https://www.mathcity.org/fsc-part1-ptb/definitions</link>
            <description>Definitions: FSc Part 1 (Mathematics): PTB

On this page, all the definitions of “Textbook of Algebra and Trigonometry Class XI, published by Punjab Textbook Board (PTB) Lahore, Pakistan are given. We are very thankful to Muhammad Waqas Sulaiman for his valuable contribution.$\frac{p}{q}$$p,q \in \mathbb{Z}$$q\neq 0$$\frac{p}{q}$$p,q \in \mathbb{Z}$$q\neq 0$$\mathbb{R}$$0.3333....,21.134134$$\pi = 3.1415...$$\divideontimes$$z=x+iy$$x,y \in \mathbb{R}, i = \sqrt{-1}$$x$$y$$z$$2, 3+\sqrt{3}i, \fra…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 22 Sep 2024 17:12:21 +0000</pubDate>
        </item>
        <item>
            <title>Definitions and Review</title>
            <link>https://www.mathcity.org/fsc-part1-ptb/definitions-and-review</link>
            <description>Definitions and Review

Textbook of Algebra and Trigonometry Class XI is published by Punjab Textbook Board (PTB) Lahore, Pakistan. The book has total of 14 chapters. On this page, we have posted material related to definitions, reviews and quick reviews.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:42:56 +0000</pubDate>
        </item>
        <item>
            <title>Definitions: FSc Part 1 (Mathematics): PTB by Aurang Zaib</title>
            <link>https://www.mathcity.org/fsc-part1-ptb/definitions-aurang-zaib</link>
            <description>Definitions: FSc Part 1 (Mathematics): PTB by Aurang Zaib

Definitions from Textbook of Algebra and Trigonometry Class XI, published by Punjab Textbook Board (PTB) Lahore, Pakistan. We are very thankful to Aurang Zaib for his valuable contribution.

Chapter 01: Number System
\( \dfrac{p}{q} \)\( p, q \in \mathbb{Z} \)\( q \neq 0 \)\( \dfrac{3}{4} \)\( \dfrac{7}{2} \)\( \sqrt{2} \)\( \pi \)\( \mathbb{R} \)\( 0.25 \)\( 3.75 \)\( 0.3333... \)\( 1.234234... \)\( \pi \)\( 3.1415... \)\( \sqrt{2} \)\(…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 30 Mar 2024 16:48:20 +0000</pubDate>
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        <item>
            <title>Definitions: Mathematics 11: PTB by Muzzammil Subhan</title>
            <link>https://www.mathcity.org/fsc-part1-ptb/definitions-muzzammil-subhan</link>
            <description>Definitions: Mathematics 11: PTB by Muzzammil Subhan

Definitions from Textbook of Algebra and Trigonometry Class XI, published by Punjab Textbook Board (PTB) Lahore, Pakistan. We are very thankful to Muzzammil Subhan for his valuable contribution. Download or view PDF for all definitions. Samples is given below$y=2^x$$y=e^x$$f(x)=\log_a x$$f(x)=\log_e x$$y$$x$$y$$y=x^2+3x$$x^2+xy+y^2=4$$f(-x)=f(x)$$f(-x)=-f(x)$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 22 Sep 2024 17:24:14 +0000</pubDate>
        </item>
        <item>
            <title>Old Question Papers/Model Papers HSSC-I (FSc-I): FBISE</title>
            <link>https://www.mathcity.org/fsc-part1-ptb/fbise-papers</link>
            <description>Old Question Papers/Model Papers HSSC-I (FSc-I): FBISE

[FBISE Paper Papers HSSC-I]
Old (past) question papers and model papers of mathematics for HSSC-I (FSc Part 1) conducted by Federal Board of Intermediate and Secondary Education (FBISE), Islamabad.

Paper Pattern

The recommended book for the mathematics paper is</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 11 Dec 2023 13:01:04 +0000</pubDate>
        </item>
        <item>
            <title>Important Questions: HSSC-I</title>
            <link>https://www.mathcity.org/fsc-part1-ptb/important-questions</link>
            <description>Important Questions: HSSC-I

[Important Questions FSc/ICS Part 1]
These are the important questions for “Textbook of Algebra and Trigonometry Class XI” published by Punjab Textbook Board (PTB) Lahore, Pakistan. These questions are taken from old papers. These are very helpful to understand the types of questions which may asked final paper of mathematics for FSc/ICS (HSSC) Part 1. Lot of energy has been put to collect and write these questions. These are taken from old papers of FBISE Islamabad,…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 18 Apr 2024 08:01:02 +0000</pubDate>
        </item>
        <item>
            <title>MCQs Bank: FSc-I</title>
            <link>https://www.mathcity.org/fsc-part1-ptb/mcq-bank</link>
            <description>MCQs Bank: FSc-I

Lot of high quality MCQs covering Textbook of Algebra and Trigonometry Class XI are available here. There are fourteen (14) chapters in this book, therefore MCQs of each chapters are given on separate page. This book was published by Punjab Textbook Board (PTB) Lahore, Pakistan. These MCQs are not only helpful for this book but can be considered for students of Higher Secondary Schools. Answer are also given on the same page.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:43:02 +0000</pubDate>
        </item>
        <item>
            <title>Multiple Choice Questions (MCQs)</title>
            <link>https://www.mathcity.org/fsc-part1-ptb/mcqs</link>
            <description>Multiple Choice Questions (MCQs)
Textbook of Algebra and Trigonometry Class XI is published by Punjab Textbook Board (PTB) Lahore, Pakistan. The book has total of 14 chapters.

Our plan is to give lot of Multiple Choice Questions (MCQs) for the above mentioned book. MCQs are very important because most of entry tests, admission tests and job tests consists of only MCQs.$\sqrt{3}$$n$$\sqrt{n}$$\forall a, b, c \in R$$a&lt;b \wedge c&gt;0\Rightarrow ac\geq bc$$a&lt;b \wedge c&gt;0\Rightarrow ac&gt; bc$$a&lt;b \wedge…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:43:03 +0000</pubDate>
        </item>
        <item>
            <title>FSc Part 1 Mathematics Notes/Solutions</title>
            <link>https://www.mathcity.org/fsc-part1-ptb/sol</link>
            <description>FSc Part 1 Mathematics Notes/Solutions

[FSc Part1 PTB Book Cover]
Notes (Solutions) of Textbook of Algebra and Trigonometry Class XI (Mathematics FSc Part 1 or HSSC-I), Punjab Textbook Board (PTB) Lahore.
 There are fourteen chapters in this book and we have work hard to make easy and suitable solution for students and teachers so that it help them learn things quickly and easily. Please click on a desire chapter to view the solution of any particular exercise. This work is licensed under a Cre…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 08 Aug 2023 17:59:03 +0000</pubDate>
        </item>
        <item>
            <title>Solution and Area of Oblique Triangle</title>
            <link>https://www.mathcity.org/fsc-part1-ptb/solution-and-area-of-oblique-triangle</link>
            <description>Solution and Area of Oblique Triangle

These are the common formulas used in Chapter 12 of Textbook of Algebra and Trigonometry Class XI, Punjab Textbook Board Lahore. This handout is very helpful to remember the formulas. All these formulas are given for real valued and defined trigonometric functions. A PDF file can be downloaded for high quality printing and a word file is also given if you wish to modify the contents or credit as you need.$a^2=b^2+c^2-2bc\cos \alpha$$b^2=c^2+a^2-2ca\cos \bet…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 25 Sep 2023 15:48:59 +0000</pubDate>
        </item>
        <item>
            <title>Trigonometric Formulas</title>
            <link>https://www.mathcity.org/fsc-part1-ptb/trigonometric-formulas</link>
            <description>Trigonometric Formulas

These are the common formulas used in Chapter 9 to 14 of Textbook of Algebra and Trigonometry Class XI, Punjab Textbook Board Lahore. This handout is very helpful to remember the formulas. All these formulas are given for real valued and defined trigonometric functions. A PDF file can be downloaded for high quality printing and a word file is also given if you wish to modify the contents or credit as you need.${{\sin }^{2}}\theta +{{\cos }^{2}}\theta =1$$1+{{\tan }^{2}}\t…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 25 May 2023 02:59:50 +0000</pubDate>
        </item>
        <item>
            <title>Old Question Papers/Model Papers HSSC-II (FSc-II): FBISE</title>
            <link>https://www.mathcity.org/fsc-part2-ptb/fbise-papers</link>
            <description>Old Question Papers/Model Papers HSSC-II (FSc-II): FBISE

Old (past) question papers and model papers of mathematics (math) for HSSC-II (FSc Part 2) conducted by Federal Board of Intermediate and Secondary Education (FBISE), Islamabad.

Paper Pattern</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 02 Jan 2022 18:31:48 +0000</pubDate>
        </item>
        <item>
            <title>FSc Part 1 Mathematics Notes/Solutions</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_solutions</link>
            <description>FSc Part 1 Mathematics Notes/Solutions
This is an old book. Notes of new book are available at following link: &lt;https://www.mathcity.org/math-11-pectaa&gt;

[FSc Part1 PTB Book Cover]
Notes (Solutions) of Textbook of Algebra and Trigonometry Class XI (Mathematics FSc Part 1 or HSSC-I), Punjab Textbook Board (PTB) Lahore.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 20 Jul 2025 09:10:04 +0000</pubDate>
        </item>
        <item>
            <title>FSc Part 1 (KPK Boards)</title>
            <link>https://www.mathcity.org/fsc/kpk_fsc_part_1</link>
            <description>FSc Part 1 (KPK Boards)

 These are the notes of old book. The notes of new book is AVAILABLE HERE 

[FSc Part 2 KPTP]
Notes of FSc Part 1 of “A Textbook of Mathematics For Class XI” published by Khyber Pakhtunkhwa Textbook Board, Peshawar. We are posting the notes chapter-wise. These notes are shared as open educational resources. This page will be continuously updated.$P(z)$$(\sum)$$\sum n$$\sum n^2$$\sum n^3$$n$$n$$$\frac{a}{a(a+d)}+\frac{a}{(a+d)(a+2d)}+...$$$^nP_r$$^nC_r=\left(\begin{smallm…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 12 Dec 2023 17:30:33 +0000</pubDate>
        </item>
        <item>
            <title>MCQS of Mathematics 9 (PCTB)</title>
            <link>https://www.mathcity.org/math-9th-pctb/mcqs</link>
            <description>MCQS of Mathematics 9 (PCTB)
Mathematics 9 is published by Punjab Curriculum and Textbook Board (PCTB), Lahore, Pakistan. This is a textbook for all the boards of Punjab for matriculation. The book has total of thirteen (13) chapters. The book is written by Muhammad Akhtar Shirani (Senior Subject Specialist, Mathematics), Madiha Mehmood, (Subject Specialist, Statistics) and Ghulam Murtaza (Subject Specialist, Mathematics).</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 18 Nov 2025 17:29:59 +0000</pubDate>
        </item>
        <item>
            <title>Definitions: FSc Part1 KPK</title>
            <link>https://www.mathcity.org/math-11-kpk/definitions</link>
            <description>Definitions: FSc Part1 KPK

A Textbook of Mathematics for Class XI is published by Khybar Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan. The book has total of twelve (12) chapters.

Definition of the book provide the quick overview of the book.$360^\circ$$\theta$$90^{\circ} \pm \theta, 180^{\circ} \pm \theta, 270^{\circ} \pm \theta, 360^{\circ} \pm \theta$$16^\circ 13&#039; 9&#039;&#039;$$sin(\alpha+2\pi)=sin\alpha$$sin x=\frac{2}{7}$$cos x-tan x=0$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:44:42 +0000</pubDate>
        </item>
        <item>
            <title>Definitions: Mathematics 11 NBF</title>
            <link>https://www.mathcity.org/math-11-nbf/definitions</link>
            <description>Definitions: Mathematics 11 NBF

Model Textbook of Mathematics for Class XI is published by National Book Foundation (NBF), Islamabad, Pakistan. NBF can be considered as Federal Textbook Board Islamabad. The book has total of nine (9) chapters.

Definition of the book provide the quick overview of the book.$x+iy$$x,y\in\mathbb{R}$$i^2=1$$\mathbb{C}$$x+i y$$x$$y$$x$$y$$Re(z)=x$$Im(z)=y$$z=x+i y$$\bar{z}$$\bar{z}=x-i y$$z=x+i y$$|z|$$|z|=\sqrt{x^{2}+y^{2}}$$z=x+iy$$Re(z)=x$$Im(z)=y$$Re(z^{-1})= \d…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 10 Jul 2024 18:51:53 +0000</pubDate>
        </item>
        <item>
            <title>MCQs: Math 11 NBF</title>
            <link>https://www.mathcity.org/math-11-nbf/mcqs</link>
            <description>MCQs: Math 11 NBF
Multiple Choice Questions (MCQs) of the Model Textbook of Mathematics for Class XI is published by National Book Foundation (NBF), Islamabad, Pakistan. NBF can be considered as Federal Textbook Board Islamabad. 
Unit 01: Complex Numbers
$\operatorname{part}(\mathrm{s})$$z$$z$$(0,0)$$(1,0)$$(0,1)$$(1,1)$$(0,0)$$z$$|z|$$1 / z$$-z$$\bar{z}$$\bar{z}$$x$$y$$x y$$y$$z_{1}=3+2 i$$z_{2}=5+6 i$$z_{1}&gt;z_{2}$$z_{1}&lt;z_{2}$$\overline{z_{1}}=\overline{z_{2}}$$\overline{z_{1}}=-\overline{z_{2…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 20 Oct 2024 18:55:54 +0000</pubDate>
        </item>
        <item>
            <title>Multiple Choice Questions (MCQs)</title>
            <link>https://www.mathcity.org/math-11-pectaa/mcqs</link>
            <description>Multiple Choice Questions (MCQs)

[FSC ICS Part 1 Math MCQs (11th Class) – Punjab Textbook Board]
FSC or ICS Part 1 Math Multiple Choice Questions (MCQs) (11th Class). Mathematics 11 (FSc or ICS Part 1, HSSC-I) is published by Punjab Education, Curriculum, Training and Assessment Authority (PECTAA) Lahore - Pakistan formally know as Punjab Textbook Board (PTB)</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 26 Aug 2025 11:48:11 +0000</pubDate>
        </item>
        <item>
            <title>Ch 02: Functions and Groups</title>
            <link>https://www.mathcity.org/fsc-part1-ptb/important-questions/ch02-functions-and-groups</link>
            <description>Ch 02: Functions and Groups

The important questions of Chapter 2 of Textbook of Algebra and Trigonometry Class XI is published by Punjab Textbook Board (PTB) Lahore, Pakistan has been given on this page. These questions are selected from old papers.$(2,4)$$\{a,\{b,c\}\}$$A-B=A \cup B^c$$p \longrightarrow q$$\{(1,2),(2,5),(3,7),(4,9),(5,11)\}$$\{a,b \}$$\{\{a,b\}\}$$~(p \longrightarrow q) \longrightarrow p$$A \cap(B \cup C)=(A \cap B)\cup(A \cap C)$$A=\{1,2,3,4\}$$B=\{3,4,5,6,7,8\}$$C=\{5,6,7,9,…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:47:39 +0000</pubDate>
        </item>
        <item>
            <title>MCQs by Muhammad Imran Qureshi</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_mcqs/mcqs_by_muhammad_imran_qureshi</link>
            <description>MCQs by Muhammad Imran Qureshi

MCQs of the Textbook of Algebra and Trigonometry Class XI is published by Punjab Textbook Board (PTB) Lahore, Pakistan. 

To see the keys of the MCQs, please see Key to MCQs by Muhammad Imran Qureshi.

	*  Chapter 01 | View Online  | Download PDF (166KB)

	*  Chapter 02 | View Online  | Download PDF (77KB)</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:46:06 +0000</pubDate>
        </item>
        <item>
            <title>Chapter 01: Complex Numbers</title>
            <link>https://www.mathcity.org/fsc/kpk_fsc_part_1/chapter_01_complex_numbers</link>
            <description>Chapter 01: Complex Numbers

Notes of Chapter 01: Complex Numbers of “A Textbook of Mathematics for Class XI” published by Khyber Pakhtunkhwa (KPK) Textbook Board, Pesharwar. These notes are shared as open educational resources.



[Download PDF ~ ch01-complex-numbers-fsc1-kpk.pdf]

fsc kpk_fsc_part1</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:47:20 +0000</pubDate>
        </item>
        <item>
            <title>Chapter 02: Matrices and Determinants</title>
            <link>https://www.mathcity.org/fsc/kpk_fsc_part_1/chapter_02_matrices_and_determinants</link>
            <description>Chapter 02: Matrices and Determinants

Notes of Chapter 02: Matrices and Determinants of “A Textbook of Mathematics for Class XI” published by Khyber Pakhtunkhwa (KPK) Textbook Board, Pesharwar. These notes are shared as open educational resources.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:47:20 +0000</pubDate>
        </item>
        <item>
            <title>Chapter 03: Vectors</title>
            <link>https://www.mathcity.org/fsc/kpk_fsc_part_1/chapter_03_vectors</link>
            <description>Chapter 03: Vectors

Notes of Chapter 03: Vectors of “A Textbook of Mathematics for Class XI” published by Khyber Pakhtunkhwa (KPK) Textbook Board, Pesharwar. These notes are shared as open educational resources.



[Download PDF ~ ch03-vectors-fsc1-kpk.pdf]

fsc kpk_fsc_part1</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:47:21 +0000</pubDate>
        </item>
        <item>
            <title>Chapter 04: Sequences</title>
            <link>https://www.mathcity.org/fsc/kpk_fsc_part_1/chapter_04_sequences</link>
            <description>Chapter 04: Sequences

Notes of Chapter 04: Sequences of “A Textbook of Mathematics for Class XI” published by Khyber Pakhtunkhwa (KPK) Textbook Board, Pesharwar. These notes are shared as open educational resources.



[Download PDF ~ ch04-sequences-fsc1-kpk.pdf]

fsc kpk_fsc_part1</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:47:21 +0000</pubDate>
        </item>
        <item>
            <title>Chapter 05: Miscellaneous Series</title>
            <link>https://www.mathcity.org/fsc/kpk_fsc_part_1/chapter_05_miscellaneous_series</link>
            <description>Chapter 05: Miscellaneous Series

Notes of Chapter 05: Miscellaneous Series of “A Textbook of Mathematics for Class XI” published by Khyber Pakhtunkhwa (KPK) Textbook Board, Pesharwar. These notes are shared as open educational resources.



[Download PDF ~ ch05-miscellaneous-series-fsc1-kpk.pdf]

fsc kpk_fsc_part1</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:47:22 +0000</pubDate>
        </item>
        <item>
            <title>Chapter 06: Permutation, Combination and Probability</title>
            <link>https://www.mathcity.org/fsc/kpk_fsc_part_1/chapter_06_permutation_combination_and_probability</link>
            <description>Chapter 06: Permutation, Combination and Probability

Notes of Chapter 06: Permutation, Combination and Probability of “A Textbook of Mathematics for Class XI” published by Khyber Pakhtunkhwa (KPK) Textbook Board, Pesharwar. These notes are shared as open educational resources.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:47:22 +0000</pubDate>
        </item>
        <item>
            <title>Chapter 07: Mathematical Induction and Binomial Theorem</title>
            <link>https://www.mathcity.org/fsc/kpk_fsc_part_1/chapter_07_mathematical_induction_and_binomial_theorem</link>
            <description>Chapter 07: Mathematical Induction and Binomial Theorem

Notes of Chapter 07: Mathematical Induction and Binomial Theorem of “A Textbook of Mathematics for Class XI” published by Khyber Pakhtunkhwa (KPK) Textbook Board, Pesharwar. These notes are shared as open educational resources.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:47:23 +0000</pubDate>
        </item>
        <item>
            <title>Chapter 08: Function and Graphs</title>
            <link>https://www.mathcity.org/fsc/kpk_fsc_part_1/chapter_08_functions_and_graphs</link>
            <description>Chapter 08: Function and Graphs

Notes of Chapter 08: Function and Graphs of “A Textbook of Mathematics for Class XI” published by Khyber Pakhtunkhwa (KPK) Textbook Board, Pesharwar. These notes are shared as open educational resources.



[Download PDF ~ ch08-functions-and-graphs-fsc1-kpk.pdf]

fsc kpk_fsc_part1</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:47:23 +0000</pubDate>
        </item>
        <item>
            <title>Chapter 09: Linear Programming</title>
            <link>https://www.mathcity.org/fsc/kpk_fsc_part_1/chapter_09_linear_programming</link>
            <description>Chapter 09: Linear Programming

Notes of Chapter 09: Linear Programming of “A Textbook of Mathematics for Class XI” published by Khyber Pakhtunkhwa (KPK) Textbook Board, Pesharwar. These notes are shared as open educational resources.



[Download PDF ~ ch09-linear-programming-fsc1-kpk.pdf]

fsc kpk_fsc_part1</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:47:24 +0000</pubDate>
        </item>
        <item>
            <title>Chapter 10: Trigonometric Identities of Sum and Difference of Angles</title>
            <link>https://www.mathcity.org/fsc/kpk_fsc_part_1/chapter_10_trigonometric_identities_of_sum_and_difference_of_angles</link>
            <description>Chapter 10: Trigonometric Identities of Sum and Difference of Angles

Notes of Chapter 10: Trigonometric Identities of Sum and Difference of Angles of “A Textbook of Mathematics for Class XI” published by Khyber Pakhtunkhwa (KPK) Textbook Board, Pesharwar. These notes are shared as open educational resources.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:47:25 +0000</pubDate>
        </item>
        <item>
            <title>Chapter 11: Application of Trigonometry</title>
            <link>https://www.mathcity.org/fsc/kpk_fsc_part_1/chapter_11_application_of_trigonometry</link>
            <description>Chapter 11: Application of Trigonometry

Notes of Chapter 11: Application of Trigonometry of “A Textbook of Mathematics for Class XI” published by Khyber Pakhtunkhwa (KPK) Textbook Board, Pesharwar. These notes are shared as open educational resources.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:47:26 +0000</pubDate>
        </item>
        <item>
            <title>Chapter 12: Graph of Trigonometric and Inverse Trigonometric Functions and Solutions of ...</title>
            <link>https://www.mathcity.org/fsc/kpk_fsc_part_1/chapter_12_graph_of_trigonometric_and_inverse_trigonometric_functions_and_solutions_of_trigonometric_equations</link>
            <description>Chapter 12: Graph of Trigonometric and Inverse Trigonometric Functions and Solutions of Trigonometric Equations

Notes of Chapter 12: Graph of Trigonometric and Inverse Trigonometric Functions and Solutions of Trigonometric Equations of “A Textbook of Mathematics for Class XI</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:47:26 +0000</pubDate>
        </item>
        <item>
            <title>FSc-I Mathematics KPK: View Online</title>
            <link>https://www.mathcity.org/fsc/kpk-fsc-part1-km/view</link>
            <description>FSc-I Mathematics KPK: View Online

 These are the notes of old book. The notes of new book is AVAILABLE HERE 

On this page one can view the PDF of solutions of the A Textbook of Mathematics For Class XI” published by Khyber Pakhtunkhwa Textbook Board, Peshawar, Pakistan. These notes are written by</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 12 Dec 2023 17:08:04 +0000</pubDate>
        </item>
        <item>
            <title>FSc-II Mathematics KPK: View Online</title>
            <link>https://www.mathcity.org/fsc/kpk-fsc-part2-km/view</link>
            <description>FSc-II Mathematics KPK: View Online

On this page one can view the PDF of solutions of the “Textbook of Mathematics Grade 12” published by Khyber Pakhtunkhwa Textbook Board, Peshawar, Pakistan. These notes are written by khalid. Link to PDF is given at the end of preview.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:47:19 +0000</pubDate>
        </item>
        <item>
            <title>Unit 01: Complex Numbers (Solutions)</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01</link>
            <description>Unit 01: Complex Numbers (Solutions)

This is a first unit of the book Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. On this page we have provided the solutions of the questions.$z$$z^2+a^2$$z^3-3z^2+z=5$$pz^2+qz+r=0$$p,q,r$$z$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 27 Oct 2025 18:47:40 +0000</pubDate>
        </item>
        <item>
            <title>Unit 02: Matrices and Determinants (Solutions)</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02</link>
            <description>Unit 02: Matrices and Determinants (Solutions)

This is a second unit of the book Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. On this page we have provided the solutions of the questions.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 08 Feb 2026 17:04:31 +0000</pubDate>
        </item>
        <item>
            <title>Unit 04: Sequences and Seeries</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04</link>
            <description>Unit 04: Sequences and Seeries

This is a forth unit of the book “Model Textbook of Mathematics for Class XI” published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. On this page we have provided the solutions of the questions.$n$$n$$n$$n$$n$$n$$n$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 06 Oct 2024 17:46:06 +0000</pubDate>
        </item>
        <item>
            <title>Unit 05: Polynomials</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit05</link>
            <description>Unit 05: Polynomials

[Unit 05: Polynomials]
This is a fifth unit of the book “Model Textbook of Mathematics for Class XI” published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. On this page we have provided the solutions of the questions.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 13 Oct 2024 18:05:52 +0000</pubDate>
        </item>
        <item>
            <title>Unit 06: Permutation and Combination</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06</link>
            <description>Unit 06: Permutation and Combination

This is a sixth unit of the book “Model Textbook of Mathematics for Class XI” published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. On this page we have provided the solutions of the questions.$n$$n!$$n$$r$$n$$r$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 09 Mar 2025 10:56:17 +0000</pubDate>
        </item>
        <item>
            <title>Unit 08: Fundamental of Trigonometry</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08</link>
            <description>Unit 08: Fundamental of Trigonometry

[Unit 08: Fundamental of Trigonometry]
This is a eight unit of the book “Model Textbook of Mathematics for Class XI” published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. On this page we have provided the solutions of the questions.$\cos(\alpha -\beta)=\cos \alpha \cos\beta+\sin\alpha \sin\beta$$\cos(\alpha +\beta)=\cos \alpha \cos\beta-\sin\alpha \sin\beta$$\sin(\alpha \pm \beta)=\sin \alpha \cos\beta \pm \sin\alpha \co…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 09 Nov 2024 18:51:30 +0000</pubDate>
        </item>
        <item>
            <title>Unit 09: Trigonometric Functions</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit09</link>
            <description>Unit 09: Trigonometric Functions

This is a ninth unit of the book “Model Textbook of Mathematics for Class XI” published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. On this page we have provided the solutions of the questions.$a+b \sin \theta$$a+b \cos \theta$$a+b \sin(c \theta+d)$$a+b \cos(c \theta+d)$$a, b, c$$d$$\sin \theta$$\cos \theta$$\tan \theta$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 27 Nov 2024 15:59:25 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 1.1</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit01/ex1-1-p1</link>
            <description>Question 1, Exercise 1.1

Solutions of Question 1 of Exercise 1.1 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 1(i)
${{i}^{9}}+{{i}^{19}}$\begin{align}{{i}^{9}}+{{i}^{19}}&amp;=i\cdot{{i}^{8}}+i\cdot{{i}^{18}}\\
&amp;=i\cdot{{\left( {{i}^{2}} \right)}^{4}}+i\cdot{{\left( {{i}^{2}} \right)}^{9}}\\
&amp;=i\cdot{{\left( -1 \right)}^{4}}+i\cdot{{\left( -1 \right)}^{9}}\\
&amp;=i\cdo…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 09 Sep 2023 11:22:32 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 &amp; 3, Exercise 1.1</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit01/ex1-1-p2</link>
            <description>Question 2 &amp; 3, Exercise 1.1

Solutions of Question 2 &amp; 3 of Exercise 1.1 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 2
${{i}^{107}}+{{i}^{112}}+{{i}^{122}}+{{i}^{153}}=0$\begin{align}L.H.S.&amp;={{i}^{107}}+{{i}^{112}}+{{i}^{122}}+{{i}^{153}}\\
&amp;=i\cdot i^{106}+i^{112}+i^{122}+i\cdot i^{152}\\
&amp;=i.{{\left( {{i}^{2}} \right)}^{53}}+{{\left( {{i}^{2}} \right)}^{56}}+…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 30 Sep 2023 11:59:15 +0000</pubDate>
        </item>
        <item>
            <title>Question 4, Exercise 1.1</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit01/ex1-1-p3</link>
            <description>Question 4, Exercise 1.1

Solutions of Question 4 of Exercise 1.1 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 4(i)
$\left( a,0 \right)\left( 2,-b \right)$\begin{align}&amp;\left( a,0 \right)-\left( 2,-b \right)\\
&amp;=\left( a+0i \right)-\left( 2-bi \right)\\
&amp;=\left( a-2 \right)+\left( 0+b \right)i\\
&amp;=\left( a-2 \right)+bi\end{align}$\left( -3,\dfrac{1}{2} \right)\le…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 30 Sep 2023 12:31:57 +0000</pubDate>
        </item>
        <item>
            <title>Question 5, Exercise 1.1</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit01/ex1-1-p4</link>
            <description>Question 5, Exercise 1.1

Solutions of Question 5 of Exercise 1.1 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 5(i)
$8i+11,-7+5i$\begin{align}&amp;(8i+11)\times (-7+5i)\\
&amp;=\left( 11+8i \right)\times \left( -7+5i \right)\\
&amp;=\left( -77+40{{i}^{2}} \right)+\left( 55-56 \right)i\\
&amp;=\left( -77+40\left( -1 \right) \right)+\left( 55-56 \right)i\\
&amp;=\left( -77-40 \right)+…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 30 Sep 2023 13:35:32 +0000</pubDate>
        </item>
        <item>
            <title>Question 6, Exercise 1.1</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit01/ex1-1-p5</link>
            <description>Question 6, Exercise 1.1

Solutions of Question 6 of Exercise 1.1 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 6(i)
$\dfrac{4+i}{3+5i}$$a+ib$\begin{align}\dfrac{4+i}{3+5i}&amp;=\dfrac{4+i}{3+5i}\times \dfrac{3-5i}{3-5i}\\
&amp;=\dfrac{\left( 12+5 \right)+\left( 3-20 \right)i}{9-25{{i}^{2}}}\\
&amp;=\dfrac{17-17i}{9+25}\\
&amp;=\dfrac{17}{34}-\dfrac{17}{34}i\\
&amp;=\dfrac{1}{2}-\dfr…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 30 Sep 2023 13:36:38 +0000</pubDate>
        </item>
        <item>
            <title>Question 7, Exercise 1.1</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit01/ex1-1-p6</link>
            <description>Question 7, Exercise 1.1

Solutions of Question 7 of Exercise 1.1 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 7(i)
${{z}_{1}}=1+2i$${{z}_{2}}=2+3i$$|{{z}_{1}}+{{z}_{2}}|$$z_1=1+2i$$z_2=2+3i$\begin{align}
{{z}_{1}}+{{z}_{2}}&amp;=1+2i+2+3i\\
&amp;=1+2+2i+3i\\
&amp;=3+5i
\end{align}\begin{align}
|z_1+z_2|&amp;=\sqrt{3^2+5^2}\\
&amp;=\sqrt{9+25}\\ 
&amp;=\sqrt{34}\end{align}${{z}_{1}}=1+2…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 30 Sep 2023 13:58:01 +0000</pubDate>
        </item>
        <item>
            <title>Question 8, Exercise 1.1</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit01/ex1-1-p7</link>
            <description>Question 8, Exercise 1.1

Solutions of Question 8 of Exercise 1.1 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 8(i)
$\dfrac{1-2i}{2+i}+\dfrac{4-i}{3+2i}$$a+ib.$\begin{align}&amp;\dfrac{1-2i}{2+i}+\dfrac{4-i}{3+2i}\\
&amp;=\dfrac{\left( 3+2i \right)\left( 1-2i \right)+\left( 2+i \right)\left( 4-i \right)}{\left( 2+i \right)\left( 3+2i \right)}\\
&amp;=\dfrac{\left( 3+4+2i-6i …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 30 Sep 2023 14:18:08 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 &amp; 10, Exercise 1.1</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit01/ex1-1-p8</link>
            <description>Question 9 &amp; 10, Exercise 1.1

Solutions of Question 9 &amp; 10 of Exercise 1.1 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 9
$\dfrac{\left( 3-2i \right)\left( 2+3i \right)}{\left( 1+2i \right)\left( 2-i \right)}$\begin{align}z&amp;=\dfrac{\left( 3-2i \right)\left( 2+3i \right)}{\left( 1+2i \right)\left( 2-i \right)}\\
&amp;=\dfrac{6+6+9i-4i}{2+2+4i-i}\\
&amp;=\dfrac{12+5i}{4+3…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 30 Sep 2023 15:54:12 +0000</pubDate>
        </item>
        <item>
            <title>Question 11, Exercise 1.1</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit01/ex1-1-p9</link>
            <description>Question 11, Exercise 1.1

Solutions of Question 11 of Exercise 1.1 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 11(i)
${{z}_{1}}=2-i$${{z}_{2}}=-2+i$${\rm Re}\left( \dfrac{{{z}_{1}}{{z}_{2}}}{\overline{{{z}_{1}}}} \right)$$z_1=2-i$$z_2=-2+i$$\overline{z_1}=2+i$\begin{align}
z_1 z_2&amp;=(2-i)(-2+i)\\ 
&amp;=-4+1+2i+2i\\
&amp;=-3+4i
\end{align}\begin{align}
\dfrac{z_1 z_2}{\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 30 Sep 2023 16:13:10 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 1.2</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit01/ex1-2-p1</link>
            <description>Question 1, Exercise 1.2

Solutions of Question 1 of Exercise 1.2 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 1

If ${{z}_{1}}=2+i$${{z}_{2}}=1-i$${{z}_{1}}=2+i$${{z}_{2}}=1-i$$$z_1+z_2=z_2+z_1.$$\begin{align}z_1+z_2&amp;=(2+i)+(1-i)\\ 
&amp;=3 \ldots (i) \end{align}\begin{align} 
z_2+z_1&amp;=(1-i)+(2+i)\\
&amp;=3 \ldots (ii)\end{align}$$z_1 z_2=z_2 z_1.$$\begin{align}z_1 z_2 …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 30 Sep 2023 16:27:57 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Exercise 1.2</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit01/ex1-2-p2</link>
            <description>Question 2, Exercise 1.2

Solutions of Question 2 of Exercise 1.2 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 2

$z_1=-1+i$, $z_2=3-2i$${{z}_{3}}=2-2i$${{z}_{1}}=-1+i$${{z}_{2}}=3-2i$${{z}_{3}}=2-2i$$$(z_1+z_2)+z_3=z_1+(z_2+z_3).$$\begin{align} 
{{z}_{1}}+{{z}_{2}}&amp;=\left( -1+i \right)+\left( 3-2i \right)\\
&amp;=2-i\end{align}\begin{align}
\left( {{z}_{1}}+{{z}_{2}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 30 Sep 2023 16:46:47 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 &amp; 4, Exercise 1.2</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit01/ex1-2-p3</link>
            <description>Question 3 &amp; 4, Exercise 1.2

Solutions of Question 3 &amp; 4 of Exercise 1.2 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 3
${{z}_{1}}=\sqrt{3}+\sqrt{2}i$${{z}_{2}}=\sqrt{2}-\sqrt{3}i$${{z}_{3}}=2+3i$${{z}_{1}}=\sqrt{3}+\sqrt{2}i$${{z}_{2}}=\sqrt{2}-\sqrt{3}i$${{z}_{3}}=2+3i$\begin{align}{{z}_{1}}\left( {{z}_{2}}+{{z}_{3}} \right)&amp;={{z}_{1}}{{z}_{2}}+{{z}_{1}}{{z}_{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 30 Sep 2023 17:09:17 +0000</pubDate>
        </item>
        <item>
            <title>Question 5, Exercise 1.2</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit01/ex1-2-p4</link>
            <description>Question 5, Exercise 1.2

Solutions of Question 5 of Exercise 1.2 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 5(i)
${{z}_{1}}=2+4i$${{z}_{2}}=1-3i$$\overline{{{z}_{1}}+{{z}_{2}}}=\overline{{{z}_{1}}}+\overline{{{z}_{2}}}$${{z}_{1}}=2+4i$${{z}_{2}}=1-3i$$\overline{{{z}_{1}}}=2-4i$$\overline{{{z}_{2}}}=1+3i$\begin{align}z_1+z_2&amp;=2+4i+1-3i\\
&amp;=3+i \end{align}\begin…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 30 Sep 2023 17:34:45 +0000</pubDate>
        </item>
        <item>
            <title>Question 6, Exercise 1.2</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit01/ex1-2-p5</link>
            <description>Question 6, Exercise 1.2

Solutions of Question 6 of Exercise 1.2 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 6(i)
${{z}_{1}}$${{z}_{2}}$$|{{z}_{1}}{{z}_{2}}|=|{{z}_{1}}||{{z}_{2}}|$${{z}_{1}}=a+bi$${{z}_{2}}=c+di$$|z_1=\sqrt{a^2+b^2}|$$|z_2=\sqrt{c^2+d^2}|$\begin{align}
L.H.S.&amp;=|{{z}_{1}}{{z}_{2}}|\\
&amp;=|(a+bi)(c+di)|\\ 
&amp;=|ac-bd+(ad+bc)i|\\
&amp;=\sqrt{{{(ac-bd)}^{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 30 Sep 2023 17:47:04 +0000</pubDate>
        </item>
        <item>
            <title>Question 7, Exercise 1.2</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit01/ex1-2-p6</link>
            <description>Question 7, Exercise 1.2

Solutions of Question 7 of Exercise 1.2 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 7(i)
$\dfrac{2+3i}{5-2i}$\begin{align}&amp;\dfrac{2+3i}{5-2i} \\
=&amp;\dfrac{2+3i}{5-2i}\times \dfrac{5+2i}{5+2i} \quad \text{by rationalizing} \\
=&amp;\dfrac{10-6+15i+4i}{25+4}\\
=&amp;\dfrac{4+19i}{29}\\
=&amp;\dfrac{4}{29}+\dfrac{19}{29}i \end{align}$=\dfrac{4}{29}$$=\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 30 Sep 2023 18:01:57 +0000</pubDate>
        </item>
        <item>
            <title>Question 8, Exercise 1.2</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit01/ex1-2-p7</link>
            <description>Question 8, Exercise 1.2

Solutions of Question 8 of Exercise 1.2 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 8(i)
$z+\overline{z}=2\operatorname{Re}\left( z \right)$$z=a+ib$$\overline{z}=a-ib$\begin{align}z+\overline{z}&amp;=\left( a+ib \right)+\left( a-ib \right)\\
&amp;=a+ib+a-ib\\
&amp;=2a\\
z+\overline{z}&amp;=2\operatorname{Re}\left( z \right)\end{align}$z-\overline{z}=2i…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 30 Sep 2023 18:06:01 +0000</pubDate>
        </item>
        <item>
            <title>Question 9, Exercise 1.2</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit01/ex1-2-p8</link>
            <description>Question 9, Exercise 1.2

Solutions of Question 9 of Exercise 1.2 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 9(i)
$z=3+2i,$$-|z|\leq \operatorname{Re}\left( z \right)\leq |z|$$z=3+2i$$|z|=\sqrt{9+4}=\sqrt{13}$${\rm Re}z=3=\sqrt{9}$\begin{align} &amp;-\sqrt{13} \leq \sqrt{9} \leq \sqrt{13}\\
\implies &amp;-|z|\leq \operatorname{Re}\left( z \right)\leq |z|\end{align}$z=3…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 30 Sep 2023 18:17:00 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 1.3</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit01/ex1-3-p1</link>
            <description>Question 1, Exercise 1.3

Solutions of Question 1 of Exercise 1.3 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 1(i)
\begin{align}&amp;z-4w=3i\\ 
&amp;2z+3w=11-5i\end{align}\begin{align}z-4w&amp;=3i		…(i)\\
2z+3w&amp;=11-5i	…(ii)\end{align}$2$\begin{align}2z-8w&amp;=6i		…(iii)\end{align}\[\begin{array}{cccc}
2z&amp;-8w&amp;=6i  \\  
\mathop+\limits_{-}2z&amp;\mathop+\limits_{-}3w&amp;=\mathop-\limit…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 30 Sep 2023 18:43:14 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Exercise 1.3</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit01/ex1-3-p2</link>
            <description>Question 2, Exercise 1.3

Solutions of Question 2 of Exercise 1.3 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 2(i)
$P(z)$$$P\left( z \right)={{z}^{3}}+6z+20$$$$p\left( z \right)={{z}^{3}}+6z+20$$$(z-a)$$P(z)$$P(a)=0$$z=-2$\begin{align}
P(-2)&amp;=(-2)^3+6(-2)+20\\
&amp;=-8-12+20\\
&amp;=0\end{align}$z+2$${{z}^{3}}+6z+20$$$\begin{array}{c|cccc}
-2 &amp; 1 &amp; 0 &amp; 6 &amp; 20 \\  
 &amp; \d…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 01 Oct 2023 06:52:57 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 &amp; 4, Exercise 1.3</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit01/ex1-3-p3</link>
            <description>Question 3 &amp; 4, Exercise 1.3

Solutions of Question 3 &amp; 4 of Exercise 1.3 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 3
${{z}_{1}}=-1+i$${{z}_{2}}=-1-i$${{z}^{2}}+2z+2=0$$$z^2+2z_1+2=0\quad \ldots (i)$$$z_1=-1+i$\begin{align}L.H.S &amp;= (-1+i)^2+2(-1+i)+2\\
&amp;=1-2i-1-2+2i+2\\
&amp;=0=R.H.S\end{align}$z_1=-1+i$$z_2=-1-i$\begin{align}
L.H.S&amp;=(-1-i)^2+2(-1-i)+2\\
&amp;=1+2i-1-…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 03 Oct 2023 03:15:42 +0000</pubDate>
        </item>
        <item>
            <title>Question 5, Exercise 1.3</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit01/ex1-3-p4</link>
            <description>Question 5, Exercise 1.3

Solutions of Question 5 of Exercise 1.3 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 5(i)
${{z}^{2}}+z+3=0$${{z}^{2}}+z+3=0$$a=1,\,\,\,b=1$$c=3$\begin{align}z&amp;=\dfrac{-b\pm \sqrt{{{b}^{2}}-4ac}}{2a}\\ 
z&amp;=\dfrac{-\left( 1 \right)\pm \sqrt{{{\left( 1 \right)}^{2}}-4\left( 1 \right)\left( 3 \right)}}{2\left( 1 \right)}\\
z&amp;=\dfrac{-1\pm \s…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 25 Sep 2023 12:02:44 +0000</pubDate>
        </item>
        <item>
            <title>Question 6, Exercise 1.3</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit01/ex1-3-p5</link>
            <description>Question 6, Exercise 1.3

Solutions of Question 6 of Exercise 1.3 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 6(i)
${{z}^{4}}+{{z}^{2}}+1=0$\begin{align}{{z}^{4}}+{{z}^{2}}+1&amp;=0\\
{{z}^{4}}+2\left( \dfrac{1}{2} \right){{z}^{2}}+\dfrac{1}{4}-\dfrac{1}{4}+1&amp;=0\\
{{\left( {{z}^{2}}+\dfrac{1}{2} \right)}^{2}}+\dfrac{4-1}{4}&amp;=0\\
{{\left( {{z}^{2}}+\dfrac{1}{2} \righ…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 25 Sep 2023 12:03:16 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Review Exercise 1</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit01/review-ex-1-p1</link>
            <description>Question 1, Review Exercise 1

Solutions of Question 1 of Review Exercise 1 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 1
${{\left( \dfrac{2i}{1+i} \right)}^{2}}$$i$$2i$$1-i$$i+1$$2i$$\dfrac{5+2i}{4-3i}$$-\dfrac{7}{25}+\dfrac{26}{25}i$$\dfrac{5}{4}-\dfrac{2}{3}i$$\dfrac{14}{25}+\dfrac{23}{25}i$$\dfrac{26}{7}+\dfrac{23}{7}i$$\dfrac{14}{25}+\dfrac{23}{25}i$${{i}^{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 25 Sep 2023 12:08:23 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 &amp; 3, Review Exercise 1</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit01/review-ex-1-p2</link>
            <description>Question 2 &amp; 3, Review Exercise 1

Solutions of Question 2 &amp; 3 of Review Exercise 1 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.${{i}^{n}}+{{i}^{n+1}}+{{i}^{n+2}}+{{i}^{n+3}}=0$$\forall n\in N$\begin{align}{{i}^{n}}+{{i}^{n+1}}+{{i}^{n+2}}+{{i}^{n+3}}&amp;=0\\
L.H.S.&amp;={{i}^{n}}+{{i}^{n}}\cdot i+{{i}^{n}}\cdot {{i}^{2}}+{{i}^{n}}\cdot {{i}^{3}}\\
&amp;={{i}^{n}}\left( 1+i+{{i}^{2}}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 25 Sep 2023 12:09:19 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 &amp; 5, Review Exercise 1</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit01/review-ex-1-p3</link>
            <description>Question 4 &amp; 5, Review Exercise 1

Solutions of Question 4 &amp; 5 of Review Exercise 1 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.${{z}_{1}}=2-i$${{z}_{2}}=1+i,$$|\dfrac{{{z}_{1}}+{{z}_{2}}+1}{{{z}_{1}}-{{z}_{2}}+1}|$\begin{align}{{z}_{1}}&amp;=2-i,\\
{{z}_{2}}&amp;=1+i,\\
\dfrac{{{z}_{1}}+{{z}_{2}}+1}{{{z}_{1}}-{{z}_{2}}+1}&amp;=\dfrac{\left( 2-i \right)+\left( 1+i \right)+1}{\left( 2-…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 25 Sep 2023 12:10:17 +0000</pubDate>
        </item>
        <item>
            <title>Question 6, 7 &amp; 8, Review Exercise 1</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit01/review-ex-1-p4</link>
            <description>Question 6, 7 &amp; 8, Review Exercise 1

Solutions of Question 6, 7 &amp; 8 of Review Exercise 1 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\dfrac{1}{3+4i}$\begin{align}\dfrac{1}{3+4i}&amp;=\dfrac{1}{3+4i}\times \dfrac{3-4i}{3-4i}\\
&amp;=\dfrac{3-4i}{9+16}\\
&amp;=\dfrac{3-4i}{25}\\
&amp;=\dfrac{3}{25}-\dfrac{4i}{25}\end{align}$\dfrac{3i+2}{3-2i}$\begin{align}\dfrac{3i+2}{3-2i}\\
\dfrac{3i+2}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 25 Sep 2023 12:10:41 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 10.1</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-1-p1</link>
            <description>Question 1, Exercise 10.1

Solutions of Question 1 of Exercise 10.1 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan. There are four parts in Question 1.$\sin {{37}^{\circ }}\cos {{22}^{\circ }}+\cos {{37}^{\circ }}\sin {{22}^{\circ }}$\begin{align} \sin (\alpha +\beta )=\sin \alpha \cos \beta +\cos \alpha \sin \beta, \end{align}\begin{a…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 24 Aug 2023 17:24:38 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Exercise 10.1</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-1-p2</link>
            <description>Question 2, Exercise 10.1

Solutions of Question 2 of Exercise 10.1 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\sin \dfrac{\pi }{12}$$\dfrac{\pi }{12}$$\dfrac{\pi }{3}-\dfrac{\pi }{4}$\begin{align}\sin (\alpha -\beta )=\sin \alpha \cos \beta -\cos \alpha \sin.\end{align}\begin{align} \Rightarrow \quad \sin \left( \frac{\pi }{3}-\f…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 09 Sep 2023 07:06:08 +0000</pubDate>
        </item>
        <item>
            <title>Question 3, Exercise 10.1</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-1-p3</link>
            <description>Question 3, Exercise 10.1

Solutions of Question 3 of Exercise 10.1 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\sin u=\dfrac{3}{5}$$\sin v=\dfrac{4}{5}$$u$$v$$0$$\dfrac{\pi }{2}$$\cos \left( u+v \right)$$\sin u=\dfrac{3}{5},$$0\le u\le \dfrac{\pi }{2}.$$\sin v=\dfrac{4}{5},$$0\le v\le \dfrac{\pi }{2}.$$\cos u=\pm \sqrt{1-{{\sin }^…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 24 Aug 2023 17:22:13 +0000</pubDate>
        </item>
        <item>
            <title>Question, Exercise 10.1</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-1-p4</link>
            <description>Question, Exercise 10.1

Solutions of Question 4 of Exercise 10.1 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\sin \alpha =-\dfrac{4}{5}$$\cos \beta =-\dfrac{12}{13}$$\alpha $$\beta $$\sin \left( \alpha -\beta  \right)$$\sin \alpha=-\dfrac{4}{5}$$\alpha$$\sin \beta=-\dfrac{12}{13}$$\beta$$$\cos \alpha=\pm \sqrt{1-\sin^2\alpha}.$$$\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 24 Aug 2023 17:20:29 +0000</pubDate>
        </item>
        <item>
            <title>Question 5, Exercise 10.1</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-1-p5</link>
            <description>Question 5, Exercise 10.1

Solutions of Question 5 of Exercise 10.1 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\tan \alpha =\dfrac{3}{4}$$\sec \beta =\dfrac{13}{5}$$\alpha$$\beta$$\sin \left( \alpha +\beta  \right)$$\tan\alpha =\dfrac{3}{4}$$\tan\alpha$$\alpha$\begin{align}{{\sec}^{2}}\alpha &amp;=1+{{\tan}^{2}}\alpha\\
\Rightarrow \q…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 01 Sep 2023 17:34:25 +0000</pubDate>
        </item>
        <item>
            <title>Question 6, Exercise 10.1</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-1-p6</link>
            <description>Question 6, Exercise 10.1

Solutions of Question 1 of Exercise 10.1 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\cos \alpha =2{{\cos }^{2}}\dfrac{\alpha }{2}-1=1-2{{\sin }^{2}}\dfrac{\alpha }{2}$\begin{align}L.H.S&amp;=\cos \alpha \\
\cos \alpha &amp;=\cos 2\dfrac{\alpha }{2}\\
&amp;={{\cos }^{2}}\dfrac{\alpha }{2}-{{\sin }^{2}}\dfrac{\alpha }…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 24 Aug 2023 17:14:31 +0000</pubDate>
        </item>
        <item>
            <title>Question 7, Exercise 10.1</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-1-p7</link>
            <description>Question 7, Exercise 10.1

Solutions of Question 1 of Exercise 10.1 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\cot \left( \alpha +\beta  \right)=\dfrac{\cot \alpha \cot \beta -1}{\cot \alpha +\cot \beta }$\begin{align}L.H.S.&amp;=\cot (\alpha +\beta )\\
&amp;=\dfrac{1}{\tan (\alpha +\beta )}\\
&amp;=\dfrac{1}{\,\dfrac{\tan \alpha +\tan \beta…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 24 Aug 2023 17:13:39 +0000</pubDate>
        </item>
        <item>
            <title>Question 8, Exercise 10.1</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-1-p8</link>
            <description>Question 8, Exercise 10.1

Solutions of Question 8 of Exercise 10.1 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\tan \left( \dfrac{\pi }{4}+\theta  \right)=\dfrac{\cos \theta +\sin \theta }{\cos \theta -\sin \theta }$\begin{align}L.H.S.&amp;=\tan \left( \dfrac{\pi }{4}+\theta  \right)\\ 
&amp;=\dfrac{\sin \left( \dfrac{\pi }{4}+\theta  \ri…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 09 Sep 2023 07:15:35 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 and 10, Exercise 10.1</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-1-p9</link>
            <description>Question 9 and 10, Exercise 10.1

Solutions of Question 9 and 10 of Exercise 10.1 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\dfrac{\sin \theta }{\sec 4\theta }+\dfrac{\cos \theta }{\cos ec4\theta }=\sin 5\theta $\begin{align}L.H.S.&amp;=\dfrac{\sin \theta }{\sec 4\theta }+\dfrac{\cos \theta }{\cos ec4\theta }\\
&amp;=\dfrac{\sin \theta }…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 25 Aug 2023 03:02:07 +0000</pubDate>
        </item>
        <item>
            <title>Question11 and 12, Exercise 10.1</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-1-p10</link>
            <description>Question11 and 12, Exercise 10.1

Solutions of Question 11 and 12 of Exercise 10.1 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\alpha$$\beta$$\gamma$$ABC$$\cot \dfrac{\alpha }{2}+\cot \dfrac{\beta }{2}+\cot \dfrac{\gamma }{2}=\cot \dfrac{\alpha }{2}\cot \dfrac{\beta }{2}\cot \dfrac{\gamma }{2}$$\alpha$$\beta$$\gamma$\begin{align}&amp;\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 24 Aug 2023 17:10:27 +0000</pubDate>
        </item>
        <item>
            <title>Question 13, Exercise 10.1</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-1-p11</link>
            <description>Question 13, Exercise 10.1

Solutions of Question 13 of Exercise 10.1 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$r\,\,\sin \left( \theta +\phi  \right)$$\theta$$\phi$$4\sin \theta +3\cos \theta .$$4\sin \theta +3\cos \theta$$r\sin(\theta + \varphi)$$$4\sin \theta +3\cos \theta=r\cos\varphi\sin\theta+r\sin\varphi\cos\theta --- (1)$…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 25 Aug 2023 02:54:27 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 10.2</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-2-p1</link>
            <description>Question 1, Exercise 10.2

Solutions of Question 1 of Exercise 10.2 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan. There are four parts in Question 1.$\sin 2\theta ,\,\,\cos 2\theta$$\tan 2\theta$$\tan \theta =-\dfrac{1}{5}$$\theta$$\sin \theta =\dfrac{1}{\sqrt{26}}$$\cos \theta =\dfrac{-5}{\sqrt{26}}$\begin{align}\sin 2\theta &amp;=2\sin…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 01 Sep 2023 18:26:41 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Exercise 10.2</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-2-p2</link>
            <description>Question 2, Exercise 10.2

Solutions of Question 2 of Exercise 10.2 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\sin \theta =\dfrac{5}{13}$$\theta $$\sin 2\theta $$\sin \theta =\dfrac{5}{13}$$$\cos \theta =\pm \sqrt{1-{{\sin }^{2}}\theta }.$$$\theta$$\cos$\begin{align}\cos\theta &amp;=-\sqrt{1-{{\sin }^{2}}\theta }\\
&amp;=-\sqrt{1-\left(\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 01 Sep 2023 18:35:56 +0000</pubDate>
        </item>
        <item>
            <title>Question 3, Exercise 10.2</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-2-p3</link>
            <description>Question 3, Exercise 10.2

Solutions of Question 3 of Exercise 10.2 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\sin \theta =\dfrac{4}{5}$$\theta$$\sin2\theta$$\sin \theta =\dfrac{4}{5}$$\theta$$\cos \theta =-\dfrac{3}{5}$\begin{align}\sin 2\theta &amp;=2\sin \theta \cos \theta \\
&amp;=2\left( \dfrac{4}{5} \right)\left( -\dfrac{3}{5} \rig…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 01 Sep 2023 18:50:54 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 and 5, Exercise 10.2</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-2-p4</link>
            <description>Question 4 and 5, Exercise 10.2

Solutions of Question 4 and 5 of Exercise 10.2 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\cos \theta =-\dfrac{3}{7}$$\theta $$\sin \dfrac{\theta }{2}$$\cos \theta =-\dfrac{3}{7}$$\theta$\begin{align}&amp;\pi &lt; \theta &lt; \dfrac{3\pi}{2} \\
\implies &amp;\frac{\pi}{2} &lt; \frac{\theta}{2} &lt; \dfrac{3\pi}{4}\end…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 01 Sep 2023 19:15:50 +0000</pubDate>
        </item>
        <item>
            <title>Question 6, Exercise 10.2</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-2-p5</link>
            <description>Question 6, Exercise 10.2

Solutions of Question 6 of Exercise 10.2 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\cos {{15}^{\circ }}$${{15}^{\circ }}=\dfrac{{{30}^{\circ }}}{2}$$\dfrac{\theta }{2}=\dfrac{{{30}^{\circ }}}{2}$$\cos {{15}^{\circ }}$\begin{align}\cos {{15}^{\circ }}&amp;=\cos \dfrac{{{30}^{\circ }}}{2}=\sqrt{\dfrac{1+\cos …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 01 Sep 2023 13:19:23 +0000</pubDate>
        </item>
        <item>
            <title>Question 7, Exercise 10.2</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-2-p6</link>
            <description>Question 7, Exercise 10.2

Solutions of Question 7 of Exercise 10.2 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.${{\cos }^{4}}\theta -{{\sin }^{4}}\theta =\dfrac{1}{\sec 2\theta }$\begin{align}L.H.S&amp;={{\cos }^{4}}\theta -{{\sin }^{4}}\theta \\ 
&amp;=\left( {{\cos }^{2}}\theta -{{\sin }^{2}}\theta  \right)\left( {{\cos }^{2}}\theta +{{\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 01 Sep 2023 19:18:09 +0000</pubDate>
        </item>
        <item>
            <title>Question 8 and 9, Exercise 10.2</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-2-p7</link>
            <description>Question 8 and 9, Exercise 10.2

Solutions of Question 8 and 9 of Exercise 10.2 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.${{\cos }^{4}}\theta $\begin{align}{{\cos}^{4}}\theta &amp;={{\left( {{\cos }^{2}}\theta  \right)}^{2}}\\
&amp;={{\left( \dfrac{1+\cos 2\theta }{2} \right)}^{2}}\\ 
&amp;=\dfrac{1+2\cos 2\theta +{{\cos }^{2}}2\theta }{4}\\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 02 Sep 2023 04:25:22 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 10.3</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-3-p1</link>
            <description>Question 1, Exercise 10.3

Solutions of Question 1 of Exercise 10.3 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan. There are four parts in Question 1.$2\sin 6x\sin x$$$-2\sin \alpha \sin \beta =\cos (\alpha +\beta )-\cos (\alpha -\beta ).$$$\alpha =6x$$\beta =x$\begin{align}-\,2\sin 6x\sin x&amp;=\cos (6x+x)-\cos (6x-x)\\
&amp;=\cos 7x-\cos x…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 04 Sep 2023 17:11:01 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Exercise 10.3</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-3-p2</link>
            <description>Question 2, Exercise 10.3

Solutions of Question 2 of Exercise 10.3 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$$\sin {{37}^{\circ }}+\sin {{43}^{\circ }}.$$$$\sin \alpha +\sin \beta =2\sin \left( \dfrac{\alpha +\beta }{2} \right)\cos \left( \dfrac{\alpha -\beta }{2} \right).$$$\alpha ={{37}^{\circ }}$$\beta ={{43}^{\circ }}$\begin…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 04 Sep 2023 17:29:02 +0000</pubDate>
        </item>
        <item>
            <title>Question 3, Exercise 10.3</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-3-p3</link>
            <description>Question 3, Exercise 10.3

Solutions of Question 3 of Exercise 10.3 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$$\dfrac{\cos {{75}^{\circ }}+\cos {{15}^{\circ }}}{\sin {{75}^{\circ }}-\sin {{15}^{\circ }}}=\sqrt{3}.$$$$\cos \alpha +\cos \beta =2\cos \left( \dfrac{\alpha +\beta }{2} \right)\cos \left( \dfrac{\alpha -\beta }{2} \righ…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Sep 2023 03:10:54 +0000</pubDate>
        </item>
        <item>
            <title>Question 5, Exercise 10.3</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-3-p4</link>
            <description>Question 5, Exercise 10.3

Solutions of Question 5 of Exercise 10.3 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$$\cos {{20}^{\circ }}\cos {{40}^{\circ }}\cos {{60}^{\circ }}\cos {{80}^{\circ }}=\dfrac{1}{16}.$$$2\cos \alpha \cos \beta =\cos \left( \alpha +\beta  \right)+\cos \left( \alpha -\beta  \right)$\begin{align}L.H.S.&amp;=\cos {…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Sep 2023 03:11:45 +0000</pubDate>
        </item>
        <item>
            <title>Question 5, Exercise 10.3</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-3-p5</link>
            <description>Question 5, Exercise 10.3

Solutions of Question 5 of Exercise 10.3 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\cos {{20}^{\circ }}\cos {{40}^{\circ }}\cos {{60}^{\circ }}\cos {{80}^{\circ }}=\dfrac{1}{16}$$2\cos \alpha \cos \beta =\cos \left( \alpha +\beta  \right)+\cos \left( \alpha -\beta  \right)$\begin{align}L.H.S.&amp;=\cos {{20…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Sep 2023 03:12:12 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Review Exercise 10</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/re-ex10-p1</link>
            <description>Question 1, Review Exercise 10

Solutions of Question 1 of Review Exercise 10 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\cos {{50}^{\circ }}5{0}&#039;\cos {{9}^{\circ }}1{0}&#039;-\sin {{50}^{\circ }}5{0}&#039;\sin {{9}^{\circ }}1{0}&#039;=$$0$$\dfrac{1}{2}$$1$$\dfrac{\sqrt{3}}{2}$$\dfrac{1}{2}$$\tan {{15}^{\circ }}=2-\sqrt{3}$${{\cot }^{2}}{{75}^{\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 09 Sep 2023 07:17:17 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 and 3, Review Exercise 10</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/re-ex10-p2</link>
            <description>Question 2 and 3, Review Exercise 10

Solutions of Question 2 and 3 of Review Exercise 10 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\dfrac{2\sin \theta \sin 2\theta }{\cos \theta +\cos 3\theta }=\tan 2\theta \tan \theta $\begin{align}L.H.S.&amp;=\dfrac{2\sin \theta \sin 2\theta }{\cos \theta +\cos 3\theta }\\
&amp;=\dfrac{2\sin \theta \s…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 09 Sep 2023 07:17:08 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 &amp; 5, Review Exercise 10</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/re-ex10-p3</link>
            <description>Question 4 &amp; 5, Review Exercise 10

Solutions of Question 4 &amp; 5 of Review Exercise 10 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.${{\sin }^{2}}\dfrac{\theta }{2}=\dfrac{\sin \theta \tan \dfrac{\theta }{2}}{2}$\begin{align}R.H.S.&amp;=\dfrac{\sin \theta \tan \dfrac{\theta }{2}}{2}\\
&amp;=\dfrac{\sin \theta \sin \dfrac{\theta }{2}}{2\cos \d…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 09 Sep 2023 07:19:53 +0000</pubDate>
        </item>
        <item>
            <title>Question 6 &amp; 7, Review Exercise 10</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/re-ex10-p4</link>
            <description>Question 6 &amp; 7, Review Exercise 10

Solutions of Question 6 &amp; 7 of Review Exercise 10 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\cos 4\theta =1-8{{\sin }^{2}}\theta {{\cos }^{2}}\theta $\begin{align}L.H.S&amp;=\cos 4\theta \\
&amp;=\cos 2\left( 2\theta  \right)\\
&amp;=1-2si{{n}^{2}}2\theta \\
&amp;=1-2{{\left( 2sin\theta \cos \theta  \right)}^{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 09 Sep 2023 07:22:31 +0000</pubDate>
        </item>
        <item>
            <title>Question 8 &amp; 9, Review Exercise 10</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10/re-ex10-p5</link>
            <description>Question 8 &amp; 9, Review Exercise 10

Solutions of Question 8 &amp; 9 of Review Exercise 10 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\sin \left( \dfrac{\pi }{4}-\theta  \right)\sin \left( \dfrac{\pi }{4}+\theta  \right)=\dfrac{1}{2}\cos 2\theta $$2\sin \alpha \sin \beta =\cos \left( \alpha -\beta  \right)-\cos \left( \alpha +\beta  \r…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 09 Sep 2023 07:26:47 +0000</pubDate>
        </item>
        <item>
            <title>Exercise 1.2 (Solutions)</title>
            <link>https://www.mathcity.org/fsc-part1-ptb/sol/ch01/ex1-2</link>
            <description>Exercise 1.2 (Solutions)
Notes (Solutions) of Exercise 1.2: Textbook of Algebra and Trigonometry Class XI (Mathematics FSc Part 1 or HSSC-I), Punjab Textbook Board (PTB) Lahore.
The main topics of this exercise are complex numbers, real part and imaginary part of complex numbers, properties of the fundamental operation on complex numbers, complex number as ordered pair of real numbers and special subset of complex numbers. These notes are based on the new Student Learning Outcomes (SLOs). Versio…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 09 Apr 2023 07:32:53 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 1.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01/ex1-1-p1</link>
            <description>Question 1, Exercise 1.1

Solutions of Question 1 of Exercise 1.1 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 1(i)
${{i}^{9}}+{{i}^{19}}$\begin{align}{{i}^{9}}+{{i}^{19}}&amp;=i\cdot{{i}^{8}}+i\cdot{{i}^{18}}\\
&amp;=i\cdot{{\left( {{i}^{2}} \right)}^{4}}+i\cdot{{\left( {{i}^{2}} \right)}^{9}}\\
&amp;=i\cdot{{\left( -1 \right)}^{4}}+i\cdot{{\left( -1 \right)}^{9}}\\
&amp;=i\cdo…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 22 Mar 2024 16:58:02 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 &amp; 3, Exercise 1.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01/ex1-1-p2</link>
            <description>Question 2 &amp; 3, Exercise 1.1

Solutions of Question 2 &amp; 3 of Exercise 1.1 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 2
${{i}^{107}}+{{i}^{112}}+{{i}^{122}}+{{i}^{153}}=0$\begin{align}L.H.S.&amp;={{i}^{107}}+{{i}^{112}}+{{i}^{122}}+{{i}^{153}}\\
&amp;=i\cdot i^{106}+i^{112}+i^{122}+i\cdot i^{152}\\
&amp;=i.{{\left( {{i}^{2}} \right)}^{53}}+{{\left( {{i}^{2}} \right)}^{56}}+…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 13 Apr 2024 19:11:49 +0000</pubDate>
        </item>
        <item>
            <title>Question 4, Exercise 1.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01/ex1-1-p3</link>
            <description>Question 4, Exercise 1.1

Solutions of Question 4 of Exercise 1.1 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 4(i)
$\left( a,0 \right)\left( 2,-b \right)$\begin{align}&amp;\left( a,0 \right)-\left( 2,-b \right)\\
&amp;=\left( a+0i \right)-\left( 2-bi \right)\\
&amp;=\left( a-2 \right)+\left( 0+b \right)i\\
&amp;=\left( a-2 \right)+bi\end{align}$\left( -3,\dfrac{1}{2} \right)\le…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:44:52 +0000</pubDate>
        </item>
        <item>
            <title>Question 5, Exercise 1.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01/ex1-1-p4</link>
            <description>Question 5, Exercise 1.1

Solutions of Question 5 of Exercise 1.1 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 5(i)
$8i+11,-7+5i$\begin{align}&amp;(8i+11)\times (-7+5i)\\
&amp;=\left( 11+8i \right)\times \left( -7+5i \right)\\
&amp;=\left( -77+40{{i}^{2}} \right)+\left( 55-56 \right)i\\
&amp;=\left( -77+40\left( -1 \right) \right)+\left( 55-56 \right)i\\
&amp;=\left( -77-40 \right)+…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:44:52 +0000</pubDate>
        </item>
        <item>
            <title>Question 6, Exercise 1.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01/ex1-1-p5</link>
            <description>Question 6, Exercise 1.1

Solutions of Question 6 of Exercise 1.1 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 6(i)
$\dfrac{4+i}{3+5i}$$a+ib$\begin{align}\dfrac{4+i}{3+5i}&amp;=\dfrac{4+i}{3+5i}\times \dfrac{3-5i}{3-5i}\\
&amp;=\dfrac{\left( 12+5 \right)+\left( 3-20 \right)i}{9-25{{i}^{2}}}\\
&amp;=\dfrac{17-17i}{9+25}\\
&amp;=\dfrac{17}{34}-\dfrac{17}{34}i\\
&amp;=\dfrac{1}{2}-\dfr…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:44:53 +0000</pubDate>
        </item>
        <item>
            <title>Question 7, Exercise 1.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01/ex1-1-p6</link>
            <description>Question 7, Exercise 1.1

Solutions of Question 7 of Exercise 1.1 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 7(i)
${{z}_{1}}=1+2i$${{z}_{2}}=2+3i$$|{{z}_{1}}+{{z}_{2}}|$$z_1=1+2i$$z_2=2+3i$\begin{align}
{{z}_{1}}+{{z}_{2}}&amp;=1+2i+2+3i\\
&amp;=1+2+2i+3i\\
&amp;=3+5i
\end{align}\begin{align}
|z_1+z_2|&amp;=\sqrt{3^2+5^2}\\
&amp;=\sqrt{9+25}\\ 
&amp;=\sqrt{34}\end{align}${{z}_{1}}=1+2…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:44:54 +0000</pubDate>
        </item>
        <item>
            <title>Question 8, Exercise 1.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01/ex1-1-p7</link>
            <description>Question 8, Exercise 1.1

Solutions of Question 8 of Exercise 1.1 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 8(i)
$\dfrac{1-2i}{2+i}+\dfrac{4-i}{3+2i}$$a+ib.$\begin{align}&amp;\dfrac{1-2i}{2+i}+\dfrac{4-i}{3+2i}\\
&amp;=\dfrac{\left( 3+2i \right)\left( 1-2i \right)+\left( 2+i \right)\left( 4-i \right)}{\left( 2+i \right)\left( 3+2i \right)}\\
&amp;=\dfrac{\left( 3+4+2i-6i …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:44:55 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 &amp; 10, Exercise 1.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01/ex1-1-p8</link>
            <description>Question 9 &amp; 10, Exercise 1.1

Solutions of Question 9 &amp; 10 of Exercise 1.1 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 9
$\dfrac{\left( 3-2i \right)\left( 2+3i \right)}{\left( 1+2i \right)\left( 2-i \right)}$\begin{align}z&amp;=\dfrac{\left( 3-2i \right)\left( 2+3i \right)}{\left( 1+2i \right)\left( 2-i \right)}\\
&amp;=\dfrac{6+6+9i-4i}{2+2+4i-i}\\
&amp;=\dfrac{12+5i}{4+3…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:44:55 +0000</pubDate>
        </item>
        <item>
            <title>Question 11, Exercise 1.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01/ex1-1-p9</link>
            <description>Question 11, Exercise 1.1

Solutions of Question 11 of Exercise 1.1 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 11(i)
${{z}_{1}}=2-i$${{z}_{2}}=-2+i$${\rm Re}\left( \dfrac{{{z}_{1}}{{z}_{2}}}{\overline{{{z}_{1}}}} \right)$$z_1=2-i$$z_2=-2+i$$\overline{z_1}=2+i$\begin{align}
z_1 z_2&amp;=(2-i)(-2+i)\\ 
&amp;=-4+1+2i+2i\\
&amp;=-3+4i
\end{align}\begin{align}
\dfrac{z_1 z_2}{\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:44:56 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 1.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01/ex1-2-p1</link>
            <description>Question 1, Exercise 1.2

Solutions of Question 1 of Exercise 1.2 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 1

If ${{z}_{1}}=2+i$${{z}_{2}}=1-i$${{z}_{1}}=2+i$${{z}_{2}}=1-i$$$z_1+z_2=z_2+z_1.$$\begin{align}z_1+z_2&amp;=(2+i)+(1-i)\\ 
&amp;=3 \ldots (i) \end{align}\begin{align} 
z_2+z_1&amp;=(1-i)+(2+i)\\
&amp;=3 \ldots (ii)\end{align}$$z_1 z_2=z_2 z_1.$$\begin{align}z_1 z_2 …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:44:56 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Exercise 1.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01/ex1-2-p2</link>
            <description>Question 2, Exercise 1.2

Solutions of Question 2 of Exercise 1.2 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 2

$z_1=-1+i$, $z_2=3-2i$${{z}_{3}}=2-2i$${{z}_{1}}=-1+i$${{z}_{2}}=3-2i$${{z}_{3}}=2-2i$$$(z_1+z_2)+z_3=z_1+(z_2+z_3).$$\begin{align} 
{{z}_{1}}+{{z}_{2}}&amp;=\left( -1+i \right)+\left( 3-2i \right)\\
&amp;=2-i\end{align}\begin{align}
\left( {{z}_{1}}+{{z}_{2}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:44:57 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 &amp; 4, Exercise 1.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01/ex1-2-p3</link>
            <description>Question 3 &amp; 4, Exercise 1.2

Solutions of Question 3 &amp; 4 of Exercise 1.2 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 3
${{z}_{1}}=\sqrt{3}+\sqrt{2}i$${{z}_{2}}=\sqrt{2}-\sqrt{3}i$${{z}_{3}}=2+3i$${{z}_{1}}=\sqrt{3}+\sqrt{2}i$${{z}_{2}}=\sqrt{2}-\sqrt{3}i$${{z}_{3}}=2+3i$\begin{align}{{z}_{1}}\left( {{z}_{2}}+{{z}_{3}} \right)&amp;={{z}_{1}}{{z}_{2}}+{{z}_{1}}{{z}_{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:44:58 +0000</pubDate>
        </item>
        <item>
            <title>Question 5, Exercise 1.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01/ex1-2-p4</link>
            <description>Question 5, Exercise 1.2

Solutions of Question 5 of Exercise 1.2 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 5(i)
${{z}_{1}}=2+4i$${{z}_{2}}=1-3i$$\overline{{{z}_{1}}+{{z}_{2}}}=\overline{{{z}_{1}}}+\overline{{{z}_{2}}}$${{z}_{1}}=2+4i$${{z}_{2}}=1-3i$$\overline{{{z}_{1}}}=2-4i$$\overline{{{z}_{2}}}=1+3i$\begin{align}z_1+z_2&amp;=2+4i+1-3i\\
&amp;=3+i \end{align}\begin…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:44:59 +0000</pubDate>
        </item>
        <item>
            <title>Question 6, Exercise 1.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01/ex1-2-p5</link>
            <description>Question 6, Exercise 1.2

Solutions of Question 6 of Exercise 1.2 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 6(i)
${{z}_{1}}$${{z}_{2}}$$|{{z}_{1}}{{z}_{2}}|=|{{z}_{1}}||{{z}_{2}}|$${{z}_{1}}=a+bi$${{z}_{2}}=c+di$$|z_1=\sqrt{a^2+b^2}|$$|z_2=\sqrt{c^2+d^2}|$\begin{align}
L.H.S.&amp;=|{{z}_{1}}{{z}_{2}}|\\
&amp;=|(a+bi)(c+di)|\\ 
&amp;=|ac-bd+(ad+bc)i|\\
&amp;=\sqrt{{{(ac-bd)}^{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:44:59 +0000</pubDate>
        </item>
        <item>
            <title>Question 7, Exercise 1.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01/ex1-2-p6</link>
            <description>Question 7, Exercise 1.2

Solutions of Question 7 of Exercise 1.2 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 7(i)
$\dfrac{2+3i}{5-2i}$\begin{align}&amp;\dfrac{2+3i}{5-2i} \\
=&amp;\dfrac{2+3i}{5-2i}\times \dfrac{5+2i}{5+2i} \quad \text{by rationalizing} \\
=&amp;\dfrac{10-6+15i+4i}{25+4}\\
=&amp;\dfrac{4+19i}{29}\\
=&amp;\dfrac{4}{29}+\dfrac{19}{29}i \end{align}$=\dfrac{4}{29}$$=\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:00 +0000</pubDate>
        </item>
        <item>
            <title>Question 8, Exercise 1.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01/ex1-2-p7</link>
            <description>Question 8, Exercise 1.2

Solutions of Question 8 of Exercise 1.2 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 8(i)
$z+\overline{z}=2\operatorname{Re}\left( z \right)$$z=a+ib$$\overline{z}=a-ib$\begin{align}z+\overline{z}&amp;=\left( a+ib \right)+\left( a-ib \right)\\
&amp;=a+ib+a-ib\\
&amp;=2a\\
z+\overline{z}&amp;=2\operatorname{Re}\left( z \right)\end{align}$z-\overline{z}=2i…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:00 +0000</pubDate>
        </item>
        <item>
            <title>Question 9, Exercise 1.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01/ex1-2-p8</link>
            <description>Question 9, Exercise 1.2

Solutions of Question 9 of Exercise 1.2 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 9(i)
$z=3+2i,$$-|z|\leq \operatorname{Re}\left( z \right)\leq |z|$$z=3+2i$$|z|=\sqrt{9+4}=\sqrt{13}$${\rm Re}z=3=\sqrt{9}$\begin{align} &amp;-\sqrt{13} \leq \sqrt{9} \leq \sqrt{13}\\
\implies &amp;-|z|\leq \operatorname{Re}\left( z \right)\leq |z|\end{align}$z=3…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:01 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 1.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01/ex1-3-p1</link>
            <description>Question 1, Exercise 1.3

Solutions of Question 1 of Exercise 1.3 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 1(i)
\begin{align}&amp;z-4w=3i\\ 
&amp;2z+3w=11-5i\end{align}\begin{align}z-4w&amp;=3i		…(i)\\
2z+3w&amp;=11-5i	…(ii)\end{align}$2$\begin{align}2z-8w&amp;=6i		…(iii)\end{align}\[\begin{array}{cccc}
2z&amp;-8w&amp;=6i  \\  
\mathop+\limits_{-}2z&amp;\mathop+\limits_{-}3w&amp;=\mathop-\limit…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:01 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Exercise 1.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01/ex1-3-p2</link>
            <description>Question 2, Exercise 1.3

Solutions of Question 2 of Exercise 1.3 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 2(i)
$P(z)$$$P\left( z \right)={{z}^{3}}+6z+20$$$$p\left( z \right)={{z}^{3}}+6z+20$$$(z-a)$$P(z)$$P(a)=0$$z=-2$\begin{align}
P(-2)&amp;=(-2)^3+6(-2)+20\\
&amp;=-8-12+20\\
&amp;=0\end{align}$z+2$${{z}^{3}}+6z+20$$$\begin{array}{c|cccc}
-2 &amp; 1 &amp; 0 &amp; 6 &amp; 20 \\  
 &amp; \d…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:02 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 &amp; 4, Exercise 1.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01/ex1-3-p3</link>
            <description>Question 3 &amp; 4, Exercise 1.3

Solutions of Question 3 &amp; 4 of Exercise 1.3 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 3
${{z}_{1}}=-1+i$${{z}_{2}}=-1-i$${{z}^{2}}+2z+2=0$$$z^2+2z_1+2=0\quad \ldots (i)$$$z_1=-1+i$\begin{align}L.H.S &amp;= (-1+i)^2+2(-1+i)+2\\
&amp;=1-2i-1-2+2i+2\\
&amp;=0=R.H.S\end{align}$z_1=-1+i$$z_2=-1-i$\begin{align}
L.H.S&amp;=(-1-i)^2+2(-1-i)+2\\
&amp;=1+2i-1-…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:03 +0000</pubDate>
        </item>
        <item>
            <title>Question 5, Exercise 1.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01/ex1-3-p4</link>
            <description>Question 5, Exercise 1.3

Solutions of Question 5 of Exercise 1.3 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 5(i)
${{z}^{2}}+z+3=0$$${{z}^{2}}+z+3=0.$$$a=1$$b=1$$c=3$\begin{align}z&amp;=\dfrac{-b\pm \sqrt{{{b}^{2}}-4ac}}{2a}\\ 
&amp;=\dfrac{-1\pm \sqrt{{{\left( 1 \right)}^{2}}-4\left( 1 \right)\left( 3 \right)}}{2\left( 1 \right)}\\
&amp;=\dfrac{-1\pm \sqrt{1-12}}{2}\\
&amp;=\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:04 +0000</pubDate>
        </item>
        <item>
            <title>Question 6, Exercise 1.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01/ex1-3-p5</link>
            <description>Question 6, Exercise 1.3

Solutions of Question 6 of Exercise 1.3 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 6(i)
${{z}^{4}}+{{z}^{2}}+1=0$$$z^4+z^2+1=0$$$$z^4+2z^2+1-z^2=0$$$$( z^2+1 )^2-z^2=0$$$$( z^2+1+z)( z^2+1-z )=0$$$$( z^2+z+1 )( z^2-z+1 )=0$$$$(z^2+z+1 )=0$$$$z=\dfrac{-1\pm \sqrt{1-4}}{2}$$$$z=\dfrac{-1\pm \sqrt{3}i}{2}$$$$(z^2-z+1 )=0$$$$z=\dfrac{1\pm …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:04 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Review Exercise 1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01/review-ex-1-p1</link>
            <description>Question 1, Review Exercise 1

Solutions of Question 1 of Review Exercise 1 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 1
${{\left( \dfrac{2i}{1+i} \right)}^{2}}$$i$$2i$$1-i$$i+1$$2i$$\dfrac{5+2i}{4-3i}$$-\dfrac{7}{25}+\dfrac{26}{25}i$$\dfrac{5}{4}-\dfrac{2}{3}i$$\dfrac{14}{25}+\dfrac{23}{25}i$$\dfrac{26}{7}+\dfrac{23}{7}i$$\dfrac{14}{25}+\dfrac{23}{25}i$${{i}^{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:05 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 &amp; 3, Review Exercise 1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01/review-ex-1-p2</link>
            <description>Question 2 &amp; 3, Review Exercise 1

Solutions of Question 2 &amp; 3 of Review Exercise 1 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.${{i}^{n}}+{{i}^{n+1}}+{{i}^{n+2}}+{{i}^{n+3}}=0$$\forall n\in N$\begin{align}{{i}^{n}}+{{i}^{n+1}}+{{i}^{n+2}}+{{i}^{n+3}}&amp;=0\\
L.H.S.&amp;={{i}^{n}}+{{i}^{n}}\cdot i+{{i}^{n}}\cdot {{i}^{2}}+{{i}^{n}}\cdot {{i}^{3}}\\
&amp;={{i}^{n}}\left( 1+i+{{i}^{2}}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:05 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 &amp; 5, Review Exercise 1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01/review-ex-1-p3</link>
            <description>Question 4 &amp; 5, Review Exercise 1

Solutions of Question 4 &amp; 5 of Review Exercise 1 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.${{z}_{1}}=2-i$${{z}_{2}}=1+i,$$\left|\dfrac{{{z}_{1}}+{{z}_{2}}+1}{{{z}_{1}}-{{z}_{2}}+1}\right|$$z_1=2-i$$z_2=1+i$\begin{align}
\dfrac{{{z}_{1}}+{{z}_{2}}+1}{{{z}_{1}}-{{z}_{2}}+1}&amp;=\dfrac{\left( 2-i \right)+\left( 1+i \right)+1}{\left( 2-i \rig…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:06 +0000</pubDate>
        </item>
        <item>
            <title>Question 6, 7 &amp; 8, Review Exercise 1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01/review-ex-1-p4</link>
            <description>Question 6, 7 &amp; 8, Review Exercise 1

Solutions of Question 6, 7 &amp; 8 of Review Exercise 1 of Unit 01: Complex Numbers. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\dfrac{1}{3+4i}$$$z=\dfrac{1}{3+4i}.$$\begin{align}z&amp;=\dfrac{1}{3+4i}\times \dfrac{3-4i}{3-4i}\\
&amp;=\dfrac{3-4i}{9+16}\\
&amp;=\dfrac{3-4i}{25}\\
&amp;=\dfrac{3}{25}-\dfrac{4}{25}i\end{align}$$\bar{z}=\dfrac{3}{25}+\dfrac{4}{25}i.$$$\dfrac{3i+2}{3-2…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:06 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 2.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-1-p1</link>
            <description>Question 1, Exercise 2.1

Solutions of Question 1 of Exercise 2.1 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 1(i)
$$\left[ \begin{matrix}
1 &amp; 2 &amp; 4  \\
\end{matrix} \right]
\left[ \begin{matrix}
1 &amp; 0 &amp; 2  \\
2 &amp; 0 &amp; 1  \\
0 &amp; 1 &amp; 2  \\
\end{matrix} \right]
\left[ \begin{matrix}
2  \\
4  \\
6  \\
\end{matrix} \right]$$\begin{align}&amp;\left[ \begin{matri…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:10 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Exercise 2.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-1-p2</link>
            <description>Question 2, Exercise 2.1

Solutions of Question 2 of Exercise 2.1 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 2
$A=\begin{bmatrix}2 &amp; -5 &amp; 1\\ 3 &amp; 0 &amp; -4\end{bmatrix}$$B=\begin{bmatrix}1 &amp; -2 &amp; -3 \\ 0 &amp; -1 &amp; 5\end{bmatrix}$$C=\begin{bmatrix}0 &amp; 1 &amp; -2\\0 &amp; -1 &amp; -1\end{bmatrix}$$2A+3B-4C.$$A=\begin{bmatrix}2 &amp; -5 &amp; 1\\ 3 &amp; 0 &amp; -4\end{bmatrix}$$B=\begin…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:13 +0000</pubDate>
        </item>
        <item>
            <title>Question 3, Exercise 2.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-1-p3</link>
            <description>Question 3, Exercise 2.1

Solutions of Question 3 of Exercise 2.1 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 3(i)
$A=\begin{bmatrix}x &amp; y &amp; z\end{bmatrix}$$B=\begin{bmatrix}a &amp; h &amp; g\\h &amp; b &amp; f\\g &amp; f &amp; c\end{bmatrix}$$C=\begin{bmatrix}x\\y\\z\end{bmatrix}$$\left( AB \right)C=A\left( BC \right)$$A=\begin{bmatrix}x &amp; y &amp; z\end{bmatrix}$$B=\begin{bmatri…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:13 +0000</pubDate>
        </item>
        <item>
            <title>Question 4, Exercise 2.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-1-p4</link>
            <description>Question 4, Exercise 2.1

Solutions of Question 4 of Exercise 2.1 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 4
$A= \begin{bmatrix}1 &amp; 4 &amp; 4  \\ 4 &amp; 1 &amp; 4  \\ 4 &amp; 4 &amp; 1 \end{bmatrix}$$\dfrac{1}{3}A^2-2A-9I=0$$A=\begin{bmatrix} 1 &amp; 4 &amp; 4  \\ 4 &amp; 1 &amp; 4  \\ 4 &amp; 4 &amp; 1 \end{bmatrix}$\begin{align}\frac{1}{3}A^2&amp;=\frac{1}{3}\left[ \begin{matrix}
   1 &amp; 4 &amp; 4 …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:14 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 &amp; 6, Exercise 2.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-1-p5</link>
            <description>Question 5 &amp; 6, Exercise 2.1

Solutions of Question 5 &amp; 6 of Exercise 2.1 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$A= \begin{bmatrix} 0 &amp; 2b &amp; -2  \\ 3 &amp; 1 &amp; 3  \\ 3a &amp; 3 &amp; -1 \end{bmatrix}$$a$$b$$A=\begin{bmatrix} 0 &amp; 2b &amp; -2  \\ 3 &amp; 1 &amp; 3  \\ 3a &amp; 3 &amp; -1 \end{bmatrix}$$$A^t=\left[ \begin{matrix}
   0 &amp; 3 &amp; 3a  \\
   2b &amp; 1 &amp; 3  \\
   -2 &amp; 3 &amp; -1  \\
\end{ma…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:14 +0000</pubDate>
        </item>
        <item>
            <title>Question 7, Exercise 2.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-1-p6</link>
            <description>Question 7, Exercise 2.1

Solutions of Question 7 of Exercise 2.1 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 7
$ A=\begin{bmatrix}1 &amp; 0 &amp; -1 &amp; 2  \\3 &amp; 1 &amp; 2 &amp; \quad 5  \\0 &amp; -2 &amp; 1 &amp; 6\end{bmatrix}$$ B=\begin{bmatrix} 2 &amp; -1 &amp; 3 &amp; 1  \\1 &amp; 3 &amp; -1 &amp; 4  \\3 &amp; 1 &amp; 2 &amp; -1 \end{bmatrix}$$( A+B )^t=A^t+B^t$$A=\left[  \begin{matrix}1 &amp; 0 &amp; -1 &amp; 2  \\3 &amp; 1 &amp;…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:15 +0000</pubDate>
        </item>
        <item>
            <title>Question 8, Exercise 2.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-1-p7</link>
            <description>Question 8, Exercise 2.1

Solutions of Question 8 of Exercise 2.1 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 8(i)
$A=\begin{bmatrix}1 &amp; 2 &amp; 0  \\3 &amp; -1 &amp; 4 \end{bmatrix}$$( A^t )^t=A$$$A=\left[ \begin{matrix}
   1 &amp; 2 &amp; 0  \\
   3 &amp; -1 &amp; 4  \\
\end{matrix}  \right]$$$$A^t=\left[  \begin{matrix}
   1 &amp; 3  \\
   2 &amp; -1  \\
   0 &amp; 4  \\
\end{matrix} \rig…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:16 +0000</pubDate>
        </item>
        <item>
            <title>Question 9, Exercise 2.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-1-p8</link>
            <description>Question 9, Exercise 2.1

Solutions of Question 9 of Exercise 2.1 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 9(i)
$A=\begin{bmatrix}2 &amp; -1 &amp; 3  \\1 &amp; \quad 0 &amp; 1 \end{bmatrix},$$B=\begin{bmatrix}1 &amp; 2  \\2 &amp; 2  \\ 3 &amp; 0 \end{bmatrix}$$( AB )^t=B^tA^t$$$A=\left[  \begin{matrix}
   2 &amp; -1 &amp; 3  \\
   1 &amp; \quad 0 &amp; 1  \\
\end{matrix}  \right],$$$$B=\left[…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:17 +0000</pubDate>
        </item>
        <item>
            <title>Question 10, Exercise 2.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-1-p9</link>
            <description>Question 10, Exercise 2.1

Solutions of Question 10 of Exercise 2.1 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 10
$A=\begin{bmatrix}1 &amp; -3 &amp; 4  \\-3 &amp; 2 &amp; -5  \\4 &amp; -5 &amp; 0 \end{bmatrix}$$B=\begin{bmatrix}5 &amp; 6 &amp; 7 \\6 &amp; -8 &amp; 3  \\7 &amp; 3 &amp; 1 \end{bmatrix}$$A$$B$$A+B$$$A=\left[ \begin{matrix}
   1 &amp; -3 &amp; 4  \\
   -3 &amp; 2 &amp; -5  \\
   4 &amp; -5 &amp; 0  \\
\end{ma…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:17 +0000</pubDate>
        </item>
        <item>
            <title>Question 11, Exercise 2.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-1-p10</link>
            <description>Question 11, Exercise 2.1

Solutions of Question 11 of Exercise 2.1 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 11
$A=\begin{bmatrix}0 &amp; 1 &amp; -2  \\-1 &amp; 0 &amp; 3  \\2 &amp; -3 &amp; 0 \end{bmatrix}$$B=\begin{bmatrix}0 &amp; -6 &amp; 11  \\6 &amp; 0 &amp; -7  \\-11 &amp; 7 &amp; 0 \end{bmatrix}$$A+B$$$A=\left[ \begin{matrix}
   0 &amp; 1 &amp; -2  \\
   -1 &amp; 0 &amp; 3  \\
   2 &amp; -3 &amp; 0  \\
\end{matri…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:10 +0000</pubDate>
        </item>
        <item>
            <title>Question 12, Exercise 2.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-1-p11</link>
            <description>Question 12, Exercise 2.1

Solutions of Question 12 of Exercise 2.1 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 12(i)
$A=\begin{bmatrix}3 &amp; 2 &amp; 1  \\4 &amp; 5 &amp; 6  \\-2 &amp; 3 &amp; 4\end{bmatrix}$$A+A^t$$$A=\left[ \begin{matrix}
   3 &amp; 2 &amp; 1  \\
   4 &amp; 5 &amp; 6  \\
   -2 &amp; 3 &amp; 4  \\
\end{matrix} \right]$$$$A^t=\left[ \begin{matrix}
   3 &amp; 4 &amp; -2  \\
   2 &amp; 5 &amp; 3  \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:12 +0000</pubDate>
        </item>
        <item>
            <title>Question 13, Exercise 2.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-1-p12</link>
            <description>Question 13, Exercise 2.1

Solutions of Question 13 of Exercise 2.1 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 13(i)
$A$$3$$A+A^t$$$A=\left[ \begin{matrix}
   a_{11} &amp; a_{12} &amp; a_{13}  \\
   a_{21} &amp; a_{22} &amp; a_{23}  \\
   a_{31} &amp; a_{32} &amp; a_{33}  \\
\end{matrix} \right]$$$$A^t=\left[ \begin{matrix}
   a_{11} &amp; a_{21} &amp; a_{31}  \\
   a_{12} &amp; a_{22} …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:12 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-2-p1</link>
            <description>Question 1, Exercise 2.2

Solutions of Question 1 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 1
$A=\begin{bmatrix}1 &amp; 3 &amp; 1  \\-1 &amp; 2 &amp; 0  \\2 &amp; 0 &amp; -2 \end{bmatrix}$$A_{11},A_{21},A_{23},A_{31},A_{32},A_{33}.$$|A|.$$$A=\left[ \begin{matrix}
   1 &amp; 3 &amp; 1  \\
   -1 &amp; 2 &amp; 0  \\
   2 &amp; 0 &amp; -2  \\
\end{matrix} \right]$$$${{A}_{11}}={{\left(…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:18 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-2-p2</link>
            <description>Question 2, Exercise 2.2

Solutions of Question 2 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 2(i)
$$\left| \begin{matrix}
   1 &amp; 2 &amp; 0  \\
   3 &amp; 1 &amp; 0  \\
   -1 &amp; 2 &amp; 0  \\
\end{matrix} \right|=0$$$\left| \begin{matrix}1 &amp; 2 &amp; 3  \\-8 &amp; 4 &amp; -12  \\2 &amp; -1 &amp; 3 \end{matrix} \right|=0$$$\left| \begin{matrix}
   1 &amp; 2 &amp; 3  \\
   -8 &amp; 4 &amp; -…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:22 +0000</pubDate>
        </item>
        <item>
            <title>Question 3, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-2-p3</link>
            <description>Question 3, Exercise 2.2

Solutions of Question 3 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 3
$A$$3,$$|A^t|=|A|$$$A=\begin{bmatrix}
   a_{11} &amp; a_{12} &amp; a_{13}  \\
   a_{21} &amp; a_{22} &amp; a_{23}  \\
   a_{31} &amp; a_{32} &amp; a_{33}  \\
\end{bmatrix}$$\begin{align}|A|&amp;=a_{11} \left( a_{22} a_{33}-a_{23} a_{32} \right)-a_{12}\left( a_{21}a_{33}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:23 +0000</pubDate>
        </item>
        <item>
            <title>Question 4, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-2-p4</link>
            <description>Question 4, Exercise 2.2

Solutions of Question 4 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 4(i)
$\left| \begin{matrix}0 &amp; 1 &amp; 3  \\-1 &amp; 2 &amp; 1  \\2 &amp; 1 &amp; 1 \end{matrix} \right|.$\begin{align}&amp;\left| \begin{matrix}
   0 &amp; 1 &amp; 3  \\
   -1 &amp; 2 &amp; 1  \\
   2 &amp; 1 &amp; 1  \\
\end{matrix} \right| \\
=&amp;0\left( 2-1 \right)-1\left( -1-2 \right)+3\l…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:24 +0000</pubDate>
        </item>
        <item>
            <title>Question 5, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-2-p5</link>
            <description>Question 5, Exercise 2.2

Solutions of Question 5 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 5(i)
$\begin{vmatrix}a &amp; b &amp; c\\l &amp; m &amp; n\\x &amp; y &amp; z \end{vmatrix}=\begin{vmatrix}a &amp; l &amp; x\\b &amp; m &amp; y\\c &amp; n &amp; z \end{vmatrix}$\begin{align}L.H.S.&amp;=\begin{vmatrix}
a &amp; b &amp; c  \\
l &amp; m &amp; n  \\
x &amp; y &amp; z
\end{vmatrix}\\
&amp;=\begin{vmatrix}
a &amp; b &amp;…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:25 +0000</pubDate>
        </item>
        <item>
            <title>Question 6, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-2-p6</link>
            <description>Question 6, Exercise 2.2

Solutions of Question 6 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Questiopn 6(i)
$\left| \begin{matrix}a-b &amp; b-c &amp; c-a  \\b-c &amp; c-a &amp; a-b  \\c-a &amp; a-b &amp; b-c  \end{matrix} \right|=0$\begin{align} L.H.S&amp;=\left| \begin{matrix}
a-b &amp; b-c &amp; c-a  \\
b-c &amp; c-a &amp; a-b  \\
c-a &amp; a-b &amp; b-c  \\
\end{matrix} \right| \\ 
&amp;=\left| \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:25 +0000</pubDate>
        </item>
        <item>
            <title>Question 7, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-2-p7</link>
            <description>Question 7, Exercise 2.2

Solutions of Question 7 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 7(i)
$\left| \begin{matrix}3860 &amp; 3861  \\3862 &amp; 3863 \end{matrix} \right|$$$\left| \begin{matrix}
   3860 &amp; 3861  \\
   3862 &amp; 3863  \\
\end{matrix} \right|=14911180-14911182$$$$=-2$$$\left| \begin{matrix}81 &amp; 82 &amp; 83  \\84 &amp; 85 &amp; 86  \\87 &amp; 8…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:26 +0000</pubDate>
        </item>
        <item>
            <title>Question 8,9 &amp; 10, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-2-p8</link>
            <description>Question 8,9 &amp; 10, Exercise 2.2

Solutions of Questions 8,9 &amp; 10 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\left| \begin{matrix}1+x &amp; y &amp; z  \\x &amp; 1+y &amp; z  \\x &amp; y &amp; 1+z \end{matrix} \right|=1+x+y+z$$$L.H.S.=\left| \begin{matrix}
   1+x &amp; y &amp; z  \\
   x &amp; 1+y &amp; z  \\
   x &amp; y &amp; 1+z  \\
\end{matrix} \right|$$$$=\left| \begin{matrix}
   1 &amp; 0 &amp; -…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:26 +0000</pubDate>
        </item>
        <item>
            <title>Question 11, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-2-p9</link>
            <description>Question 11, Exercise 2.2

Solutions of Question 11 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 11(i)
$\left[ \begin{matrix}7 &amp; 1 &amp; 3  \\6 &amp; 2 &amp; -2  \\5 &amp; 1 &amp; 1\end{matrix} \right]$$$A=\left[ \begin{matrix}
   7 &amp; 1 &amp; 3  \\
   6 &amp; 2 &amp; -2  \\
   5 &amp; 1 &amp; 1  \\
\end{matrix} \right]$$$$|A|=7(2+2)-1(6+10)+3(6-10)$$$$=28-16-12$$$$|A|=0$$$A$$\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:28 +0000</pubDate>
        </item>
        <item>
            <title>Question 12, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-2-p10</link>
            <description>Question 12, Exercise 2.2

Solutions of Question 12 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 12
$\lambda $$A$$A=\begin{bmatrix}-\lambda  &amp; 1 &amp; 0  \\1 &amp; -\lambda  &amp; 1  \\0 &amp; 1 &amp; -\lambda \end{bmatrix}$$$A=\left[ \begin{matrix}
   -\lambda  &amp; 1 &amp; 0  \\
   1 &amp; -\lambda  &amp; 1  \\
   0 &amp; 1 &amp; -\lambda   \\
\end{matrix} \right]$$$$|A|=-\lamb…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:18 +0000</pubDate>
        </item>
        <item>
            <title>Question 13, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-2-p11</link>
            <description>Question 13, Exercise 2.2

Solutions of Question 13 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 13(i)
$x,$$\left| \begin{matrix}x &amp; 2 &amp; 3  \\0 &amp; -1 &amp; 1  \\0 &amp; 4 &amp; 5 \end{matrix} \right|=9$$$\left| \begin{matrix}
   x &amp; 2 &amp; 3  \\
   0 &amp; -1 &amp; 1  \\
   0 &amp; 4 &amp; 5  \\
\end{matrix} \right|=9$$$$x(-5-4)-2(0)+3(0)=9$$$$-9x=9$$$$x=-1$$$x,$$\left…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:19 +0000</pubDate>
        </item>
        <item>
            <title>Question 14 &amp; 15, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-2-p12</link>
            <description>Question 14 &amp; 15, Exercise 2.2

Solutions of Questions 14 &amp; 15 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$A=\begin{bmatrix}0 &amp; 2 &amp; 2  \\-1 &amp; 3 &amp; 2  \\1 &amp; 0 &amp; 5\end{bmatrix}$$A^{-1}$$$A=\left[ \begin{matrix}
   0 &amp; 2 &amp; 2  \\
   -1 &amp; 3 &amp; 2  \\
   1 &amp; 0 &amp; 5  \\
\end{matrix} \right]$$$A^{-1}$$$A^{-1}=\dfrac{Adj\,\,A}{|A|}$$$$Adj\,\,A={{\left[ \begin…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:20 +0000</pubDate>
        </item>
        <item>
            <title>Question 16 &amp; 17, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-2-p13</link>
            <description>Question 16 &amp; 17, Exercise 2.2

Solutions of Questions 16 &amp; 17 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$A=\begin{bmatrix}3 &amp; -1  \\4 &amp; 2\end{bmatrix}$$|A^{-1}|=\dfrac{1}{|A|}$$$A=\left[ \begin{matrix}
   3 &amp; -1  \\
   4 &amp; 2  \\
\end{matrix} \right]$$$$|A|=6+4$$$$\Rightarrow |A|=10\ldots (1)$$$$A^{-1}=\dfrac{1}{|A|}AdjA$$$$AdjA=\left[ \begin{ma…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:21 +0000</pubDate>
        </item>
        <item>
            <title>Question 18, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-2-p14</link>
            <description>Question 18, Exercise 2.2

Solutions of Question 18 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 18(i)
$A$$B$$( A^{-1})^{-1}=A$$A$$2\times 2$$$A=\left[ \begin{matrix}
   a_{11} &amp; a_{12}  \\
   a_{21} &amp; a_{22}  \\
\end{matrix} \right]$$$$|A|=a_{11}a_{22}-a_{12}a_{21}$$$$AdjA=\left[ \begin{matrix}
   a_{22} &amp; -a_{12}  \\
   -a_{21} &amp; a_{11…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:21 +0000</pubDate>
        </item>
        <item>
            <title>Question 19, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-2-p15</link>
            <description>Question 19, Exercise 2.2

Solutions of Question 19 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 19
$A=\begin{bmatrix}2 &amp; 3  \\-1 &amp; 1\end{bmatrix}$$( A^{-1})^t=( A^t)^{-1}$$$A=\left[ \begin{matrix}
   2 &amp; 3  \\
   -1 &amp; 1  \\
\end{matrix} \right]$$$$A^t=\left[ \begin{matrix}
   2 &amp; -1  \\
   3 &amp; 1  \\
\end{matrix} \right]$$$$|A^t|=5$$$$Ad…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:22 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 2.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-3-p1</link>
            <description>Question 1, Exercise 2.3

Solutions of Question 1 of Exercise 2.3 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 1(i)
$\begin{bmatrix}1 &amp; 3 &amp; -1  \\2 &amp; 1 &amp; 4  \\3 &amp; 4 &amp; -5\end{bmatrix}$\begin{align}&amp;\begin{bmatrix}
1 &amp; 3 &amp; -1  \\
2 &amp; 1 &amp; 4  \\
3 &amp; 4 &amp; -5 \end{bmatrix}\\
\underset{\sim}{R}&amp;\begin{bmatrix}
1 &amp; 3 &amp; -1  \\
0 &amp; -5 &amp; 6  \\
0 &amp; -5 &amp; -2 \end{bmat…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:29 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Exercise 2.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-3-p2</link>
            <description>Question 2, Exercise 2.3

Solutions of Question 2 of Exercise 2.3 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 2(i)
$$\begin{bmatrix}4 &amp; -2 &amp; 5 \\ 2 &amp; 1 &amp; 0  \\ -1 &amp; 2 &amp; 3  \end{bmatrix}$$$$A=\begin{bmatrix}
4 &amp; -2 &amp; 5  \\
2 &amp; 1 &amp; 0  \\
-1 &amp; 2 &amp; 3 \end{bmatrix}.$$\begin{align}|A|&amp;=\begin{vmatrix}4 &amp; -2 &amp; 5  \\ 2 &amp; 1 &amp; 0  \\ -1 &amp; 2 &amp; 3 \end{vmatrix}\\
&amp;=…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:29 +0000</pubDate>
        </item>
        <item>
            <title>Question 3, Exercise 2.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-3-p3</link>
            <description>Question 3, Exercise 2.3

Solutions of Question 3 of Exercise 2.3 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 3(i)
$$\left[ \begin{matrix}
   1 &amp; 0 &amp; -2  \\
   2 &amp; 2 &amp; 1  \\
   -1 &amp; 2 &amp; 3  \\
\end{matrix} \right]$$\begin{align}&amp;\begin{bmatrix}
1 &amp; 0 &amp; -2  \\
2 &amp; 2 &amp; 1  \\
-1 &amp; 2 &amp; 3 \end{bmatrix}\\
\underset{\sim}{R}&amp; \begin{bmatrix}
1 &amp; 0 &amp; -2  \\
0 &amp;…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:30 +0000</pubDate>
        </item>
        <item>
            <title>Question 4, Exercise 2.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-3-p4</link>
            <description>Question 4, Exercise 2.3

Solutions of Question 4 of Exercise 2.3 of Unit 02: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 4
$\begin{bmatrix}2 &amp; 3 &amp; 4 &amp; 5  \\3 &amp; 4 &amp; 5 &amp; 6  \\4 &amp; 5 &amp; 6 &amp; 7  \\9 &amp; 10 &amp; 11 &amp; 12\end{bmatrix}$\begin{align}&amp;\begin{bmatrix}
2 &amp; 3 &amp; 4 &amp; 5  \\
3 &amp; 4 &amp; 5 &amp; 6  \\
4 &amp; 5 &amp; 6 &amp; 7  \\
9 &amp; 10 &amp; 11 &amp; 12 \end{bmatrix}\\
\underset{\sim}{R}&amp;\begin{bm…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:32 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 3.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-2-p1</link>
            <description>Question 1, Exercise 3.2

Solutions of Question 1 of Exercise 3.2 of Unit 03: Matrices and Determinants. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question.1(i)
$\vec{a}=3\hat{i}-5\hat{j}$$\vec{b}=-2\hat{i}+3\hat{j}$$\vec{a}+2\vec{b}$\begin{align}\vec{a}+2\vec{b}&amp;=3\hat{i}-5\hat{j}+2(-2\hat{i}+3\hat{j})\\
&amp;=3\hat{i}-5\hat{j}-4\hat{i}+6\hat{j}\\
&amp;=-\hat{i}+\hat{j}\end{align}$\vec{a}=3\hat{i}-5\hat{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:30 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Exercise 3.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-2-p2</link>
            <description>Question 2, Exercise 3.2

Solutions of Question 2 of Exercise 3.2 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 2(i)

Find unit vector having the same direction as the vector $3\hat{i}.$$$\overset{\scriptscriptstyle\rightharpoonup}{a}=3\hat{i}$$$$|\overset{\scriptscriptstyle\rightharpoonup}{a}|=\sqrt{{{(3)}^{2}}}=3$$$$\hat{a}=\dfrac{{\overset{\scriptscriptstyle\rightharpo…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:29 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 &amp; 4, Exercise 3.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-2-p3</link>
            <description>Question 3 &amp; 4, Exercise 3.2

Solutions of Question 3 &amp; 4 of Exercise 3.2 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 3

If $\vec{r}=\hat{i}-9\hat{j}$$\vec{a}=\hat{i}+2\hat{j}$$\vec{b}=5\hat{i}-\hat{j}$$p$$q$$\vec{r}=p\vec{a}+q\vec{b}$$$\vec{r}=p\vec{a}+q\vec{b}.$$$\vec{r},\vec{a}$$\vec{b}$$$\hat{i}-9\hat{j}=p(\hat{i}+2\hat{j})+q(5\hat{i}-\hat{j})$$$$\implies \hat{i}-9\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:31 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 &amp; 6, Exercise 3.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-2-p4</link>
            <description>Question 5 &amp; 6, Exercise 3.2

Solutions of Question 5 &amp; 6 of Exercise 3.2 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 5

Find the length of the vector $\overrightarrow{AB}$$\vec{A}(-3,5)$$\vec{B}(7,9)$$\overrightarrow{AB}$$\vec{A}$$\vec{B}$$$\overrightarrow{OA}=-3\hat{i}+5\hat{j},$$$$\overrightarrow{OB}=7\hat{i}+9\hat{j}.$$\begin{align}\overrightarrow{AB}&amp;=\overrightarr…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:31 +0000</pubDate>
        </item>
        <item>
            <title>Question 7, Exercise 3.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-2-p5</link>
            <description>Question 7, Exercise 3.2

Solutions of Question 7 of Exercise 3.2 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 7(i)

Find the components and the magnitude of $\overrightarrow{PQ}$$P(-1,2)$$Q(2,-1)$\begin{align}\overrightarrow{PQ}&amp;=\overrightarrow{OQ}-\overrightarrow{OP}\\ 
&amp;=(2\hat{i}-\hat{j})-(-\hat{i}+2\hat{j})\\ 
&amp;=3\hat{i}-3\hat{j}\end{align}\begin{align}|\overrighta…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:32 +0000</pubDate>
        </item>
        <item>
            <title>Question 7, Exercise 3.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-2-p6</link>
            <description>Question 7, Exercise 3.2

Solutions of Question 7 of Exercise 3.2 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 7(i)

Find the components and the magnitude of $\overrightarrow{PQ}$$P(-1,2)$$Q(2,-1)$\begin{align}\overrightarrow{PQ}&amp;=\overrightarrow{OQ}-\overrightarrow{OP}\\ 
&amp;=(2\hat{i}-\hat{j})-(-\hat{i}+2\hat{j})\\ 
&amp;=3\hat{i}-3\hat{j}\end{align}\begin{align}|\overrighta…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:33 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 &amp; 10, Exercise 3.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-2-p7</link>
            <description>Question 9 &amp; 10, Exercise 3.2

Solutions of Question 9 &amp; 10 of Exercise 3.2 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 9
$\overrightarrow{a}=\hat{i}+\hat{j}+\hat{k}, $$$ and $$, find a vector of magnitude of $$ unit which is parallel to the vector $\begin{align}2\overrightarrow{a}-\overrightarrow{b}+3\overrightarrow{c}&amp;=2(\hat{i}+\hat{j}+\hat{k})-(4\hat{i}-2\hat{j}+3\h…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:34 +0000</pubDate>
        </item>
        <item>
            <title>Question 11, Exercise 3.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-2-p8</link>
            <description>Question 11, Exercise 3.2

Solutions of Question 11 of Exercise 3.2 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 11(i)

Find the position vectors of the point of division of the line segments joining point $C$$5\hat{j}$$D$$4\hat{i}+\hat{j}$$2:5$$C$$\overrightarrow{OC}=5\hat{j}$$D$$\overrightarrow{OD}=4\hat{i}+\hat{j}$$H$$\overline{CD}$$2:5$$H$\begin{align}\overrightarrow…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:35 +0000</pubDate>
        </item>
        <item>
            <title>Question 12, 13 &amp; 14, Exercise 3.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-2-p9</link>
            <description>Question 12, 13 &amp; 14, Exercise 3.2

Solutions of Question 12, 13 &amp; 14 of Exercise 3.2 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 12
$\alpha ,$$|\alpha \hat{i}+(\alpha +1)\hat{j}+2\hat{k}|=3$\begin{align}|\alpha \hat{i}+(\alpha +1)\hat{j}+2\hat{k}|&amp;=3.\end{align}\begin{align}\sqrt{(\alpha )^2+(\alpha +1)^2+(2)^2}&amp;=3.\end{align}\begin{align}&amp;{\alpha ^2+(\alpha +1)^2}+4=9…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:36 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 3.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-3-p1</link>
            <description>Question 1, Exercise 3.3

Solutions of Question 1 of Exercise 3.3 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 1(i)

If $\vec{a}=3 \hat{i}+4 \hat{j}-\hat{k}$, $\vec{b}=\hat{i}-\hat{j}+3 \hat{k}$ and $\vec{c}=2\hat{i}+\hat{j}-5 \hat{k}$$\vec{a}\cdot \vec{b}$\begin{align}\vec{a} \cdot \vec{b}&amp;=(3 \hat{i}+4 \hat{j}-\hat{k}) \cdot(\hat{i}-\hat{j}+3 \hat{k})\\
\Rightarrow &amp;=(…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:36 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 and 3 Exercise 3.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-3-p2</link>
            <description>Question 2 and 3 Exercise 3.3

Solutions of Question 2 and 3 of Exercise 3.3 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 2
$$\vec{a}=2 \hat{i} + 2 \hat{j}-5 \hat{k}, \quad \vec{b}=2 \hat{i}+\hat{j}-7 \hat{k}$$\begin{align}\vec{a}+\vec{b}&amp;=(2 \hat{i}+2 \hat{j}-5 \hat{k})+(2 \hat{i}+\hat{j}-7 \hat{k}) \\
\Rightarrow &amp;=4 \hat{i}+3 \hat{j}-12 \hat{k}\\
\Rightarrow|\vec{a}+\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:37 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 and 5 Exercise 3.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-3-p3</link>
            <description>Question 4 and 5 Exercise 3.3

Solutions of Question 4 and 5 of Exercise 3.3 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 4
$\hat{i}+7 \hat{j} + 3 \hat{k}$$\hat{i}-\hat{j}+2 \hat{k}$$2 \hat{i}-$$\hat{j}+3 \hat{k}$$\vec{a}=\hat{i}+7 \hat{j}+3 \hat{k}$$\vec{b}=\hat{i}-\hat{j}+2 \hat{k}$$\vec{c} = 2 \hat{i}-\hat{j}-3 \hat{k}$\begin{align}\vec{a} \cdot \vec{b}&amp;=(\hat{i}+7 \h…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:37 +0000</pubDate>
        </item>
        <item>
            <title>Question 6 Exercise 3.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-3-p4</link>
            <description>Question 6 Exercise 3.3

Solutions of Question 6 of Exercise 3.3 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 6(i)

Let $\vec{a}=\hat{i}+3 \hat{j}-4 \hat{k}$ and $\vec{b}=2 \hat{i}-3 \hat{j}-5 \hat{k}$$m$$\vec{a}+m \vec{b}$$\vec{a}$\begin{align}
\vec{a}+m \vec{b}&amp; =\hat{i}+3 \hat{j}-4 \hat{k}+m(2 \hat{i}-3 \hat{j}+5 \hat{k}) \\
&amp; =(1+2 m) \hat{i}+(3-3 m) \hat{j}+(5 m-4) …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:38 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 &amp; 8 Exercise 3.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-3-p5</link>
            <description>Question 7 &amp; 8 Exercise 3.3

Solutions of Question 7 &amp; 8 of Exercise 3.3 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 7(i)
$\vec{a}$$\vec{b}$$\vec{a}=-\dfrac{3}{2} \hat{j}+\dfrac{4}{5} \hat{k} \cdot \vec{b}=\hat{i}-2 \hat{j}-2 \hat{k}$$\vec{a}$$\vec{b}$$\vec{b}$$\vec{a}$$\vec{a}=-\dfrac{3}{2} \hat{j}+\dfrac{4}{5} \hat{k}\quad$$\vec{b}=\hat{i}-2 \hat{j}-2 \hat{k}$\begin{a…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:39 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 &amp; 10, Exercise 3.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-3-p6</link>
            <description>Question 9 &amp; 10, Exercise 3.3

Solutions of Question 9 &amp; 10 of Exercise 3.3 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 9
$\vec{k}-2 \hat{i}+3 \hat{j}+\hat{k}$$\vec{S}=2 \hat{i}+\hat{j}-\hat{k}$\begin{align}W &amp;=\vec{F} \cdot s \\
\Rightarrow W &amp;=(2 \hat{i}+3 \hat{j}+\hat{k}) \cdot(2 \hat{i}+\hat{j}-\hat{k}) \\
\Rightarrow W &amp;=2(2) \div 3(1)+1(-1) \\
\Rightarrow W &amp;=4+3 …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:39 +0000</pubDate>
        </item>
        <item>
            <title>Question 11, Exercise 3.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-3-p7</link>
            <description>Question 11, Exercise 3.3

Solutions of Question 11 of Exercise 3.3 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 11 (i)

Show that the vectors $3 \hat{i}-2 \hat{j}+$$\hat{k} . \quad \hat{i}-3 \hat{j}-5 \hat{k}$$2 \hat{i}+\hat{j}-4 \hat{k}$$\vec{a}=3 \hat{i}-2 \hat{j}+\hat{k}$$\vec{b}=\hat{i}-3 \hat{j}+5 \hat{k}$$\vec{c}=2 \hat{i}+\hat{j}-4 \hat{k}$\begin{align}|\vec{a}|&amp;…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:40 +0000</pubDate>
        </item>
        <item>
            <title>Question 12 &amp; 13, Exercise 3.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-3-p8</link>
            <description>Question 12 &amp; 13, Exercise 3.3

Solutions of Question 12 &amp; 13 of Exercise 3.3 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 12
$\overrightarrow{B A} \cdot \overrightarrow{A C}=0$$|\vec{a}|=\vec{b}|=| \vec{c} \mid=$$\vec{b}=-\vec{c}$$\triangle A B O$\begin{align}\overrightarrow{O B}+\overrightarrow{A B}&amp;=\overrightarrow{O A}\\
\Rightarrow \overrightarrow{B A}&amp;=\overrightar…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:41 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 Exercise 3.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-4-p1</link>
            <description>Question 1 Exercise 3.4

Solutions of Question 1 of Exercise 3.4 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 1(i)

Find the cross product $\hat{j} \times(2 \hat{j}+3 \hat{k})$\begin{align}\vec{a}=\hat{j}&amp;=0 \hat{i}+\hat{j}+0 \hat{k}\\
\vec{b}&amp;=0 \hat{i}+2 \hat{j}-3 \hat{k}\\
 \vec{a} \times \vec{b}&amp;=\hat{j} \times(2 \hat{j}+3 \hat{k})\\
&amp;=\left|\begin{array}{lll}\hat{i}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:42 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 Exercise 3.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-4-p2</link>
            <description>Question 2 Exercise 3.4

Solutions of Question 2 of Exercise 3.4 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 2(i)

Show in two different ways that the vectors $\vec{a}$$\vec{b}$$\vec{a}=-\hat{i}+2 \hat{j}-3 \hat{k}, \quad \vec{b}=2 \hat{i}-4 \hat{j}+$$6 \hat{k}$\begin{align}\vec{a} \times \vec{b}&amp;=\left|\begin{array}{ccc}
\hat{i} &amp; \hat{j} &amp; \hat{k} \\
-1 &amp; 2 &amp; -3 \\
2 …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:43 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 Exercise 3.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-4-p3</link>
            <description>Question 3 Exercise 3.4

Solutions of Question 3 of Exercise 3.4 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 3(i)

Find a unit vector that is orthogonal to
the given vector $\vec{a}=\hat{i}- 2 \hat{j}+3 \hat{k}, \quad \vec{b}=2 \hat{i}+\hat{j}-\hat{k}$$\hat{n}$$\vec{a}$$\vec{b}$\begin{align}\hat{n}&amp;=\dfrac{\vec{a} \times \vec{b}}{\mid \vec{a} \times \vec{b}} \\
\text { …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:43 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 Exercise 3.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-4-p4</link>
            <description>Question 4 Exercise 3.4

Solutions of Question 4 of Exercise 3.4 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 4(i)

If $\vec{a}=3 \hat{i}-6 \hat{j}+5 \hat{k},\quad\vec{b}=2\hat{i}-\hat{j}+4 \hat{k} \quad$ and $\quad \vec{c}=\hat{i}+\hat{j} \quad \hat{k},\quad$$\vec{a} \times \vec{b}$\begin{align}\vec{a} \times \vec{b}&amp;=\left|\begin{array}{ccc}
\hat{i} &amp; \hat{j} &amp; \hat{k}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:44 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 Exercise 3.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-4-p5</link>
            <description>Question 5 Exercise 3.4

Solutions of Question 5 of Exercise 3.4 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 5(i)

Use the vector product to compute the area of the triangle with the given vertices $P(-2,-3), \quad Q(3,2)\quad$$\quad R(-1,-8)$$P Q$$\bar{P} R$\begin{align}\text{Area of triangle}&amp;=\dfrac{1}{2}|\overrightarrow{P Q} \times \overrightarrow{P R}| \\
\text { S…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:45 +0000</pubDate>
        </item>
        <item>
            <title>Question 6 Exercise 3.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-4-p6</link>
            <description>Question 6 Exercise 3.4

Solutions of Question 6 of Exercise 3.4 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 6(i)

A force $\vec{F}=3 \hat{i}-2 \hat{j}+5 \hat{k}$$(1,-2,2)$$\vec{r}$$P(1,-2.2)$$O(0,0,0)$\begin{align}\vec{r}&amp;=\overrightarrow{O P}\\
&amp;=(1,-2,2)-(0,0,0) \\
\Rightarrow \vec{r}&amp;=(1,-2,2).\\
\text { Hence } \vec{M}-\vec{r} \times \vec{F}&amp;=\left|\begin{array}{cc…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:46 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 &amp; 8 Exercise 3.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-4-p7</link>
            <description>Question 7 &amp; 8 Exercise 3.4

Solutions of Question 7 &amp; 8 of Exercise 3.4 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 7

If $\vec{A}+\vec{B}+\vec{C}=\vec{O}$$$\vec{A} \times \vec{B}=\vec{B} \times \vec{C}=\vec{C} \times \vec{A}.$$$$\vec{A}+\vec{B}+\vec{C}=\vec{O} \text {. }$$$\vec{A}$$$\vec{A} \times(\vec{A}+\vec{B}+\vec{C})=0$$\begin{align}\Rightarrow \vec{A} \times \ve…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:46 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 Exercise 3.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-4-p8</link>
            <description>Question 9 Exercise 3.4

Solutions of Question 9 of Exercise 3.4 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 9(i)

Find the area of parallelogram whose diagonals are $\vec{a}=4 \hat{i}+\hat{j}-2 \hat{k}\quad$$\quad\vec{b}=-2 \hat{i}+3 \hat{j}+4 \hat{k}$$\vec{c}$$\vec{d}$$E$$E$\begin{align}\overrightarrow{A E}&amp;=\overrightarrow{E C}\\
&amp;=\dfrac{1}{2} \vec{a}\\
&amp;=2 \hat{i}+…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:47 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 &amp; 2 Exercise 3.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-5-p1</link>
            <description>Question 1 &amp; 2 Exercise 3.5

Solutions of Question 1 &amp; 2 of Exercise 3.5 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 1

Find $\vec{a} \cdot \vec{b} \times \vec{c}$$\vec{a}=2 \hat{i}+\hat{j}+3 \hat{k}$$\vec{b}=-\hat{i}+2 \hat{j}+\hat{k} \quad \text { and }\quad \vec{c}=3 \hat{i}+\hat{j}+2 \hat{k} \text {. }$\begin{align}V&amp;=\vec{a} \cdot \vec{b} \times \vec{c}\\
&amp;=\left|\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:47 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 &amp; 4 Exercise 3.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-5-p2</link>
            <description>Question 3 &amp; 4 Exercise 3.5

Solutions of Question 3 &amp; 4 of Exercise 3.5 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 3

For the vectors $\vec{a}=3 \hat{i}+2 \hat{k}$$\vec{b}=\hat{i}+2 \hat{j}+\hat{k}\quad$$\quad\vec{c}=-\hat{j}+4 \hat{k}$$\vec{a} \cdot \vec{b} \times \vec{c}=\vec{b} \cdot \vec{c} \times \vec{a}=\vec{c} \cdot \vec{a} \times \vec{b}$$\vec{a} \cdot \vec{b}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:48 +0000</pubDate>
        </item>
        <item>
            <title>Question 5(i) &amp; 5(ii) Exercise 3.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-5-p3</link>
            <description>Question 5(i) &amp; 5(ii) Exercise 3.5

Solutions of Question 5(i) &amp; 5(ii) of Exercise 3.5 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 5(i)
$\vec{a}=a_1 \hat{i}+a_2 \hat{j}+a_3 \hat{k}\quad$$\quad\vec{b}=b_1 \hat{i}+b_2 \hat{j}+b_3 \hat{k}\quad$$\vec{a} \times \vec{b}\quad$$\vec{a} \times \vec{b}$$\vec{a}$$\vec{b}$$\vec{a} \times \vec{b}$$\vec{a}$$\vec{b}$$\vec{a} \times \v…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:49 +0000</pubDate>
        </item>
        <item>
            <title>Question 5(iii) &amp; 5(iv) Exercise 3.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-5-p4</link>
            <description>Question 5(iii) &amp; 5(iv) Exercise 3.5

Solutions of Question 5(iii) &amp; 5(iv) of Exercise 3.5 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\vec{a}=a_1 \hat{i}+a_2 \hat{j}+a_3 \hat{k}\quad$$\quad\vec{b}=b_1 \hat{i}+b_2 \hat{j}+b_3 \hat{k}\quad$$(\vec{a}. \vec{b})^2,\quad|a|^2,\quad|b|^2$\begin{align}\vec{a} \cdot \vec{b}&amp;=(a_1 \hat{i}+a_2 \hat{j} + a_3 \hat{k}) \cdot(b_1 \hat{i}+b_2 \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:50 +0000</pubDate>
        </item>
        <item>
            <title>Question 6 Exercise 3.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-5-p5</link>
            <description>Question 6 Exercise 3.5

Solutions of Question 6 of Exercise 3.5 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 6

Do the points $(4. 2.1)$$(5,1,6)$$(2.2,-5)$$(3.5 .0)$$A(4,-2,1), B(5,1,6)$$C(2,2,-5)$$D(3,5.0)$$A, \overrightarrow{O A}=4 \hat{i}-2 \hat{j}+\hat{k}$$B, \overrightarrow{O B}=5 \hat{i}+\hat{j}+6 \hat{k}$$C, \overrightarrow{O C}=2 \hat{i}+2 \hat{i}-5 \hat{k}$$D, …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:51 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 Exercise 3.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-5-p6</link>
            <description>Question 7 Exercise 3.5

Solutions of Question 7 of Exercise 3.5 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 7(i)

For what value of $c$$\vec{u}=\hat{i}+2 \hat{j}+3 \hat{k}$$\vec{v}=2 \hat{i}-3 \hat{j}+4 \hat{k} \cdot \vec{w}=3 \hat{i}+\hat{j}+c \hat{k}$\begin{align}\vec{u} \cdot \vec{v} \times \vec{w}&amp;=0\\
\vec{u} \cdot \vec{v} \times \vec{w}&amp;=0\\
\Rightarrow\left|\beg…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:52 +0000</pubDate>
        </item>
        <item>
            <title>Question 8 Exercise 3.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-5-p7</link>
            <description>Question 8 Exercise 3.5

Solutions of Question 8 of Exercise 3.5 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 8(i)

Find the volume of tetrahedron with the Vectors as coterminous edges
\begin{align}\vec{a}&amp;=\hat{i}+2 \hat{j}+3 \hat{k},\\ 
\vec{b}&amp;=4 \hat{i}+5 \hat{j}+6 \hat{k}, \\
\vec{c}&amp;=7 \hat{j}+8 \hat{k}\end{align}\begin{align}V&amp;=\dfrac{1}{6}[\vec{u} \cdot \vec{v} \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:52 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 Exercise 3.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-5-p8</link>
            <description>Question 9 Exercise 3.5

Solutions of Question 9 of Exercise 3.5 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 9 (i)

Write the value of $(\hat{i} \times \hat{j}). \hat{k}+\hat{i}. \hat{j}$\begin{align}
(\hat{i} \times \hat{j}) \cdot \hat{k}&amp;=\left|\begin{array}{ccc}
1 &amp; 0 &amp; 0 \\
0 &amp; 1 &amp; 0 \\
0 &amp; 0 &amp; 1
\end{array}\right|&amp;=1 ....(1)\\
\text { and } \hat{i} \cdot \hat{j}&amp;=0…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:53 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 Review Exercise 3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/review-ex3-p1</link>
            <description>Question 1 Review Exercise 3

Solutions of Question 1 of Review Exercise 3 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 1

$\hat{i} \cdot(\hat{j} \times \hat{k})+\hat{j} \cdot(\hat{i} \times \hat{k})+\hat{k} \cdot(\hat{i} \times \hat{j})$$0$$1$$1$$3$$0$$3 \hat{i}+5 \hat{j}+2 \hat{k}$$2 \hat{i}-3 \hat{j}-5 \hat{k}$$5 \hat{i}+2 \hat{j}-3 \hat{k}$$\hat{i}-2 \hat{i}+\hat{j}+…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:54 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 &amp; 3 Review Exercise 3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/review-ex3-p2</link>
            <description>Question 2 &amp; 3 Review Exercise 3

Solutions of Question 2 &amp; 3 of Review Exercise 3 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 2
$\lambda$$\mu$$$(\hat{i}+3 \hat{j}+9 \hat{k}) \times(3 \hat{i}-\lambda \hat{j}+\mu \hat{k})=\overrightarrow{0} \text {. }$$\begin{align}(\hat{i}+3 \hat{j}+9 \hat{k}) \times(3 \hat{i}-\lambda \hat{j}+\mu \hat{k})&amp;=\vec{O} \\
\Rightarrow\left|\b…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:55 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 &amp; 5 Review Exercise 3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/review-ex3-p3</link>
            <description>Question 4 &amp; 5 Review Exercise 3

Solutions of Question 4 &amp; 5 of Review Exercise 3 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 4
$\vec{r}=x \hat{i}+y \hat{j}+z \hat{k}$$(\vec{r} \times \hat{i}) \cdot(\bar{r} \times \hat{j})+x y$$$(\vec{r} \times \hat{i}) \cdot(\vec{r} \times \hat{j})+x y $$\begin{align}\text { Now } \vec{r} \times \hat{i}&amp;=\left|\begin{array}{ccc}
\hat{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:55 +0000</pubDate>
        </item>
        <item>
            <title>Question 6 &amp; 7 Review Exercise 3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/review-ex3-p4</link>
            <description>Question 6 &amp; 7 Review Exercise 3

Solutions of Question 6 &amp; 7 of Review Exercise 3 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 6
$\lambda$$\vec{a}=\hat{i}+3 \hat{j}+\hat{k}$$\bar{b}=2 \hat{i}-\hat{j}-\hat{k}$$\vec{c}=\lambda \hat{j}+3 \hat{k}$\begin{align}\vec{a} \cdot \vec{b} \times \vec{c}&amp;=0 \\
\Rightarrow\left|\begin{array}{ccc}
1 &amp; 3 &amp; 1 \\
2 &amp; -1 &amp; -1 \\
0 &amp; \lamb…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:56 +0000</pubDate>
        </item>
        <item>
            <title>Question 8 &amp; 9 Review Exercise 3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/review-ex3-p5</link>
            <description>Question 8 &amp; 9 Review Exercise 3

Solutions of Question 8 &amp; 9 of Review Exercise 3 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 8
$(0,0,2),(-1,3,2),(1,0,4)$$A(0,0,2)$$B(-1,3,2)$$C(1,0,4)$$\vec{a}=\overrightarrow{A B}=(-1,3,2)-(0,0,2)$$\Rightarrow \vec{a}=(-1,3,0)$$\vec{b}=\overrightarrow{B C}=(1,0,4)-(-1,3,2)$$\Rightarrow \vec{b}=(2,-3,2)$$$ \text{Area of triangle} =\dfr…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:57 +0000</pubDate>
        </item>
        <item>
            <title>Question 10 Review Exercise 3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/review-ex3-p6</link>
            <description>Question 10 Review Exercise 3

Solutions of Question 10 of Review Exercise 3 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 10(i)
$A B C$$|\vec{a}|^2=|\vec{b}|^2+|\vec{c}|^2 -2|\vec{b}|| \vec{c}| \cos A$$A B C$$\vec{a}, \vec{b}$$\vec{c}$\begin{align}
\vec{b}&amp;=\vec{a}+\vec{c} \\
\Rightarrow \vec{a}&amp;=\vec{b}-\vec{c} \\
\Rightarrow \vec{a} \cdot \vec{a}&amp;=(\vec{b}-\vec{c}) \cd…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:58 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 and 2 Exercise 4.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-1-p1</link>
            <description>Question 1 and 2 Exercise 4.1

Solutions of Question 1 and 2 of Exercise 4.1 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$2,4,6,8, \ldots ,50$$50 $$1,0,1,0,1, \ldots$$0$$1$$...,-4,0,4,8, \ldots, 60$$1,-\dfrac{1}{3}, \dfrac{1}{9},-\dfrac{1}{27}, \ldots,-\dfrac{1}{2187}$$a_n=\dfrac{n(n+1)}{2}$$$a_n=\dfrac{n(n+1)}{2}$$$n=1,$$$a_1=\dfrac{1(1+1)}{2}=1$$$n=2$$$a_2=\dfrac{2(2…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 17:47:24 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 and 4 Exercise 4.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-1-p2</link>
            <description>Question 3 and 4 Exercise 4.1

Solutions of Question 3 and 4 of Exercise 4.1 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\dfrac{1}{2}, \dfrac{2}{3} \dfrac{3}{4}, \dfrac{4}{5}, \ldots$$$\dfrac{1}{1+1}, \dfrac{2}{2+1}, \dfrac{3}{3+1}, \dfrac{4}{4+1},...$$$\dfrac{n}{n+1}$$2,-4,6,-8,10, \ldots$\begin{align}
&amp;(-1)^2 \cdot 2 \cdot 1, (-1)^3 \cdot 2 \cdot 2, (-1)^4 \cdot 2 \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 18:19:22 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 Exercise 4.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-1-p3</link>
            <description>Question 5 Exercise 4.1

Solutions of Question 5 of Exercise 4.1 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 5(i)
$\sum_{j=1}^6(2 j-3)$\begin{align}\sum_{j=1}^6(2 j-3)&amp;=(2.1-3)+(2.2-3)+(2.3-3)+(2.4-3)\\&amp;+(2.5-3)+(2.6-3) \\
\implies \sum_{j=1}^6(2 j-3)&amp;=-1+1+3+5+7+9 .\end{align}$\sum_{k=1}^5(-1)^k 2^{k-1}$\begin{align}\sum_{k=1}^5(-1)^k 2^{k-1}&amp; =(-1)^1 2^{1-…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 18:33:10 +0000</pubDate>
        </item>
        <item>
            <title>Question 6 Exercise 4.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-1-p4</link>
            <description>Question 6 Exercise 4.1

Solutions of Question 6 of Exercise 4.1 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Note

The general recursive definition formula defined for Pascal sequences is
$$P_0=1, P_{r+1}=\dfrac{n-r}{r+1} P_r, \text{ where } r=0,1,2,3,\ldots.$$$n=5$$n=5$$$P_0=1, P_{r+1}=\dfrac{5-r}{r+1} P_r, \text{ where } r=0,1,2,3,\ldots.$$$r=0$\begin{align}&amp;P_{0+1…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 02 Feb 2024 17:51:14 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 and 2 Exercise 4.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-2-p1</link>
            <description>Question 1 and 2 Exercise 4.2

Solutions of Question 1 and 2 of Exercise 4.2 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$15$$2,5,8, \ldots$$a_1=2$$d=5-2=3$$n=15$$$a_n=a_1+(n-1) d$$\begin{align}a_{15}&amp;=2+(15-1) 3 \\
&amp;=2+42=44 \end{align}$44$$a_1=8$$a_{21}=108$$$a_n=a_1+(n-1) d.$$\begin{align}
&amp;a_{21}=8+(21-1) d \\
\implies &amp;108=8+20 d\\
\implies &amp;20 d=108-8=100 \\
\imp…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 03 Feb 2024 13:48:54 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 and 4 Exercise 4.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-2-p2</link>
            <description>Question 3 and 4 Exercise 4.2

Solutions of Question 3 and 4 of Exercise 4.2 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$6,9,12, \ldots, 78$$a_1=6$$d=9-6=3$$a_n=78$$$a_n=a_1+(n-1) d$$\begin{align}&amp;78=6+(n-1) 3 \\
\implies &amp;3(n-1)=78-6 \\
\implies &amp;n-1=\dfrac{72}{3} \\
\implies &amp;n=24+1=25.\end{align}$25$$n$$a_n=2n+7$$$a_n=2 n+7. --- (1)$$\begin{align}a_{n+1}=2(n+1)+7=2…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 04 Feb 2024 03:20:11 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 and 6 Exercise 4.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-2-p3</link>
            <description>Question 5 and 6 Exercise 4.2

Solutions of Question 5 and 6 of Exercise 4.2 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$$\log a, \log (a b), \log \left(a b^2\right), \log \left(a b^3\right), \ldots$$$n$$\log$$a$$b$$b$$$a_n=\log (a b^{n-1}).$$\begin{align}a_n&amp;=\log(a b^{n-1}). \end{align}\begin{align}
d&amp;=a_{n+1}-a_n \\
&amp;=\log (a b^n)-\log (a b^{n-1}) \\
&amp;=\log \left(\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 10 Feb 2024 16:55:28 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 Exercise 4.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-2-p4</link>
            <description>Question 7 Exercise 4.2

Solutions of Question 7 of Exercise 4.2 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 7
$a_6+a_4=6$$a_6-a_4=\dfrac{2}{3}$$a_1$$d$\begin{align} &amp;a_6+a_4=6 \\
\implies &amp; a_1+5d+a_1+3d=6\\
\implies &amp; 2a_1+8d=6\\
\implies &amp; a_1+4d=3 --- (1)
\end{align}\begin{align} &amp;a_6-a_4=\dfrac{2}{3} \\
\implies &amp; a_1+5d-a_1-3d=\dfrac{2}{3}\\
\implies &amp;…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 10 Feb 2024 17:37:24 +0000</pubDate>
        </item>
        <item>
            <title>Question 8 Exercise 4.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-2-p5</link>
            <description>Question 8 Exercise 4.2

Solutions of Question 8 of Exercise 4.2 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 8
$\dfrac{b+c-a}{a}, \dfrac{c+a-b}{b}, \dfrac{a+b-c}{c}$$\dfrac{1}{a}, \dfrac{1}{b}, \dfrac{1}{c}$$\dfrac{b+c-a}{a}, \dfrac{c+a-b}{b}, \dfrac{a+b-c}{c}$\begin{align}\therefore \dfrac{c+a-b}{b}-\dfrac{b+c-a}{a}&amp;=\dfrac{a+b-c}{c}-\dfrac{c+a-b}{b} \\
\te…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 10 Feb 2024 17:39:11 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 Exercise 4.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-2-p6</link>
            <description>Question 9 Exercise 4.2

Solutions of Question 9 of Exercise 4.2 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 9
$24m$$21m$$18m$$$a_1=24,$$$$a_2=21,$$$$a_3=18.$$$$d=21-24=18-21=-3,$$\begin{align} a_8&amp;=a_1+7d\\
&amp;=24+7(-3)=3.
\end{align}$3m$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 10 Feb 2024 18:23:08 +0000</pubDate>
        </item>
        <item>
            <title>Question 10 Exercise 4.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-2-p7</link>
            <description>Question 10 Exercise 4.2

Solutions of Question 10 of Exercise 4.2 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 10
$500$$a_1$$$a_1=20135.$$$d=-500$$a_{11}$\begin{align}
a_{11}&amp;=a_1+10d \\
&amp;=20135+10(-500)\\
&amp;=15135. \end{align}$1070$$15135$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 10 Feb 2024 18:34:21 +0000</pubDate>
        </item>
        <item>
            <title>Question 11 Exercise 4.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-2-p8</link>
            <description>Question 11 Exercise 4.2

Solutions of Question 11 of Exercise 4.2 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 11
$a_1$$$a_1=1000.$$$= d=100$$a_n=5400$$n$\begin{align}
&amp;a_n=a_1+(n-1)d \\
 \implies &amp;5400=1000+(n-1)100\\
 \implies &amp;5400=900+100n \\
 \implies &amp;100n=5400-900\\
 \implies &amp;100n=4500\\
 \implies &amp;n=45.\end{align}</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 10 Feb 2024 18:43:43 +0000</pubDate>
        </item>
        <item>
            <title>Question 12 &amp; 13 Exercise 4.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-2-p9</link>
            <description>Question 12 &amp; 13 Exercise 4.2

Solutions of Question 12 &amp; 13 of Exercise 4.2 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$a_1$$$a_1=3500.$$$=d=750$$a_{21}$\begin{align}
a_{21}&amp;=a_1+20d\\
&amp;=3500+20(750) \\
&amp;=18500. \end{align}$12$$18$$a=12, b=18$$A$\begin{align}A&amp;=\dfrac{a+b}{2}\\&amp;=\dfrac{12+18}{2}\\&amp;=\dfrac{30}{2}=15.\end{align}$\dfrac{1}{3}$$\dfrac{1}{4}$$a=\dfrac{1}{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 10 Feb 2024 19:08:43 +0000</pubDate>
        </item>
        <item>
            <title>Question 14 Exercise 4.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-2-p10</link>
            <description>Question 14 Exercise 4.2

Solutions of Question 14 of Exercise 4.2 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 14(i)
$A_1, A_2, A_3$$6, A_1, A_2, A_3, 41$$$a_1=6 \text{ and } a_6=41.$$\begin{align}&amp; a_5=11\\
\Rightarrow &amp;a_1+4 d=41 \\
\Rightarrow &amp;6+4 d=41 \\
\Rightarrow &amp;d=\dfrac{41-6}{4}\\
&amp;=\dfrac{35}{4}.\end{align}\begin{align} A_1&amp;=a+d=6+\dfrac{35}{4} \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 11 Feb 2024 10:45:10 +0000</pubDate>
        </item>
        <item>
            <title>Question 15 Exercise 4.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-2-p11</link>
            <description>Question 15 Exercise 4.2

Solutions of Question 15 of Exercise 4.2 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 15
$n, \dfrac{a^{n+1}+b^{n+1}}{a^n+b^n}$$a$$b$$a$$b$$A$$a$$b$$$
A=\dfrac{a+b}{2}. --- (1)
$$$$
A=\dfrac{a^{n+1}+b^{n+1}}{a^n+b^n}. --- (2)
$$\begin{align}&amp;\dfrac{a+b}{2}=\dfrac{a^{n+1}+b^{n+1}}{a^n+b^n}, --- (3) \\
	\implies &amp;(a^n+b^n)(a+b)=2(a^{n+1…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 11 Feb 2024 09:36:49 +0000</pubDate>
        </item>
        <item>
            <title>Question 16 Exercise 4.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-2-p12</link>
            <description>Question 16 Exercise 4.2

Solutions of Question 16 of Exercise 4.2 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 16
$5$$8$$5$$8$$A_1, A_2, A_3, A_4, A_5$$5$$8$$5, A_1, A_2, A_3, A_4, A_5, 8$$$a_1=5 \text{ and } a_7=8.$$\begin{align}&amp;a_7=a+6d\\
\implies &amp;8=5+6d\\
\implies &amp;6d=8-5\\
\implies &amp;d=\dfrac{3}{6}=\dfrac{1}{2}.
\end{align}\begin{align}
A_1&amp;=a+d=5+\dfra…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 11 Feb 2024 10:03:25 +0000</pubDate>
        </item>
        <item>
            <title>Question 17 Exercise 4.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-2-p13</link>
            <description>Question 17 Exercise 4.2

Solutions of Question 17 of Exercise 4.2 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 17
$n$$7: 13$$n$$A_1, A_2, A_3, \ldots, A_n$$n$$5, A_1, A_2, A_3, \ldots, A_n, 32$$$a_1=5 \text{ and } a_{n+2}=32.$$$a_n=a_1+(n-1) d$$n$$n+2$\begin{align}a_{n+2}&amp;=a_1+(n+2-1) d \\
	&amp; =a_1+(n+1) d \\
	\implies 32&amp;=5+(n+1)d \\
	\implies (n+1)d&amp;=32-5\\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 11 Feb 2024 10:39:35 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 Exercise 4.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-3-p1</link>
            <description>Question 1 Exercise 4.3

Solutions of Question 1 of Exercise 4.3 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 1(i)
$9,7,5,3, \ldots$$a_1$$d$\begin{align}&amp;a_1=9 \\ 
&amp;d=7-9=-2 \\
&amp;n=20.
\end{align}\begin{align}&amp;a_n=a_1+(n-1)d \\
\implies &amp;a_20=9+(20-1)(-2)=-29.
\end{align}$S_n$$n$\begin{align}
S_n&amp;=\dfrac{n}{2}[a_1+a_n], \\
\implies S_{20}&amp;=\dfrac{20}{2}[9-29] …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 11 Feb 2024 11:01:45 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 Exercise 4.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-3-p2</link>
            <description>Question 2 Exercise 4.3

Solutions of Question 2 of Exercise 4.3 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 2(i)
$a_1, a_n, n, d$$S_n$$a_1=2, n=17, d=3$$a_1=2, n=17, d=3$$a_{17}$$S_{17}$$$a_{n}=a_1+(n-1)d.$$$$a_{17}=2+(17-1)(3)=50.$$$$S_n=\dfrac{n}{2}[a_1+a_n]$$\begin{align}S_{17}&amp;=\dfrac{17}{2}(a_1+a_17) \\
&amp;=\dfrac{17}{2}(2+50)=442.\end{align}$a_{17}=50$$…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 11 Feb 2024 11:48:37 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 &amp; 4 Exercise 4.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-3-p3</link>
            <description>Question 3 &amp; 4 Exercise 4.3

Solutions of Question 3 &amp; 4 of Exercise 4.3 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 3
$5$$25$$350$$5$$25$$350$$$25,30,35, \ldots, 350.$$$a_1=25, d=5$$a_n=350$$n$\begin{align}a_n&amp;=a_1+(n-1) d\end{align}\begin{align}
350&amp;=25+(n-1)(5) \\
\Rightarrow 5 n-5+25&amp;=350 \\
\Rightarrow 5 n&amp;=350-20=330 \\
\Rightarrow n&amp;=66, \text { now f…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 12 Feb 2024 11:11:18 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 &amp; 6 Exercise 4.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-3-p4</link>
            <description>Question 5 &amp; 6 Exercise 4.3

Solutions of Question 5 &amp; 6 of Exercise 4.3 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 5
$20$$120$$$a-2 d, a-d, a+d, a+2 d,$$$Condition-1$$20$\begin{align}a-3 d+a-d+a+d+a+3 d&amp;=20 \\
\Rightarrow 4 a&amp;=20\\
\Rightarrow a&amp;=5 .\end{align}$Condition-2$$120$\begin{align}(a-3 d)^2+(a-d)^2+(a+d)^2+(a+2 d)^2&amp;=120 \\
\Rightarrow a^2-6 a d+…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:29:55 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 &amp; 8 Exercise 4.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-3-p5</link>
            <description>Question 7 &amp; 8 Exercise 4.3

Solutions of Question 7 &amp; 8 of Exercise 4.3 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 7
$1+3-5+7+9-11+13+15-$$17+\ldots$$3 n$\begin{align}&amp;(1+7+13+\ldots)+(3+9+15+\ldots)- \\
&amp; (5+11+17+\ldots) \ldots \ldots \ldots . . .(1)\end{align}$\mathrm{n}$$n$$3 n$$$1+7+13+\ldots$$$$a_1=1, d=7-1=6$$$n$\begin{align}S_n&amp;=\dfrac{n}{2}[2 a_1+…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:29:55 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 &amp; 10 Exercise 4.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-3-p6</link>
            <description>Question 9 &amp; 10 Exercise 4.3

Solutions of Question 9 &amp; 10 of Exercise 4.3 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 9
$$306,315,324,333, \ldots, 693$$$a=306$$$d=(315-306) = 9 \text { and } a_n=693 .$$$n$\begin{align}a_n&amp;=a_1+(n-1) d \text { becomes } \\
\Rightarrow a_1+(n-1) d&amp;=693 \\
\Rightarrow 306+(n-1) \cdot 9&amp;=693 \\
\Rightarrow 9 n&amp;=396 \\
\Rightarr…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:29:57 +0000</pubDate>
        </item>
        <item>
            <title>Question 11 &amp; 12 Exercise 4.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-3-p7</link>
            <description>Question 11 &amp; 12 Exercise 4.3

Solutions of Question 11 &amp; 12 of Exercise 4.3 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$16 \mathrm{ft}$$48 \mathrm{ft}$$80 \mathrm{ft}$$a_1=16 \mathrm{ft}$$2^{\text {nd }}$$a_2=48 \mathrm{ft}$$a_3=80 \mathrm{ft}$$16,48,80, \ldots \quad$$d=48-16=32$$S_6$\begin{align}S_n&amp;=\dfrac{n}{2}[2 a_1+(n-1) d] \\
\therefore S_6&amp;=\dfrac{6}{2}(2.16+5…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:29:57 +0000</pubDate>
        </item>
        <item>
            <title>Question 13 &amp; 14 Exercise 4.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-3-p8</link>
            <description>Question 13 &amp; 14 Exercise 4.3

Solutions of Question 13 &amp; 14 of Exercise 4.3 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.\begin{align}\text{Total number of rows}&amp; n=40,\\
\text{Seats in a first row} a_1&amp;=20\\
\text{Seat in a second row} a_2&amp;=23\\
\text{Seats in third row} a_3&amp;=26\end{align}$20,23,26, \ldots$$S_{40}$$$S_n=\dfrac{n}{2} [{2} a_1+(n-1) d] \text {.}$$\begin…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:29:58 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 Exercise 4.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-4-p1</link>
            <description>Question 1 Exercise 4.4

Solutions of Question 1 of Exercise 4.4 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question(i)
$a_1=5, \quad r=3$$a_1, a_1 r, a_1 r^2, a_1 r^3, a_1 r^4, \ldots$$a_1=5 ; r=3$\begin{align}&amp;5,5.3,5.3^2, 5.3^3, 5.3^4, \ldots\\
\Rightarrow &amp;5,15,45,135,405, \ldots\end{align}$a_1=8, \quad r=-\dfrac{1}{2}$$a_1, a_1 r, a_1 r^2, a_1 r^3, a_1 r^4, \ld…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:29:58 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 &amp; 3 Exercise 4.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-4-p2</link>
            <description>Question 2 &amp; 3 Exercise 4.4

Solutions of Question 2 &amp; 3 of Exercise 4.4 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 2
$27$$243$$$a_3=27 \quad\text{and}\quad a_5=243$$\begin{align}a_3&amp;=a_1 r^2=27\\
a_5&amp;=a_1 r^4=243.\end{align}\begin{align}\dfrac{a_1 r^4}{a_1 r^2}&amp;=\dfrac{243}{27}=9 \\
\Rightarrow r^2&amp;=9 \text { or } r= \pm 3 .\end{align}$$a_1(9)=27 \quad \te…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:30:00 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 &amp; 5 Exercise 4.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-4-p3</link>
            <description>Question 4 &amp; 5 Exercise 4.4

Solutions of Question 4 &amp; 5 of Exercise 4.4 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 4
$\dfrac{1}{64}$$r=\dfrac{1}{2}$$a_1=16$$a_n=\dfrac{1}{64}$$r=\dfrac{1}{2}$$n$$$a_n=a_1 r^{n-1} \quad \text{then}$$\begin{align}\dfrac{1}{64}&amp;=16(\dfrac{1}{2})^{n-1} \\
\Rightarrow(\dfrac{1}{2})^{n-1}&amp;=\dfrac{1}{64 \times 16}=\dfrac{1}{1024} …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:30:00 +0000</pubDate>
        </item>
        <item>
            <title>Question 6 &amp; 7 Exercise 4.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-4-p4</link>
            <description>Question 6 &amp; 7 Exercise 4.4

Solutions of Question 6 &amp; 7 of Exercise 4.4 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 6
$a_{10}=l, a_{13}=m$$a_{16}=n;\quad$$\ln =m^2$$a_n=a_1 r^{n-1}$\begin{align}a_{10}&amp;=a_1 r^9=l \\
a_{13}&amp;=a_1 r^{12}=m\\
\text{and} \quad a_{16}&amp;=a_1 e^{\mathbf{A 5}}=n\end{align}\begin{align}a_{10} \cdot a_{16}&amp;=\ln =(a_1 r^9)(a_1 r^{15})\\
…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:30:01 +0000</pubDate>
        </item>
        <item>
            <title>Question 8 Exercise 4.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-4-p5</link>
            <description>Question 8 Exercise 4.4

Solutions of Question 8 of Exercise 4.4 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 8(i)
$3.14$$2.71$$a=3.14$$b=2.71$$$G= \pm \sqrt{(3.14)(2.71)}= \pm 2.94$$$$G=2.94 \quad \text{or} \quad -2.94$$$-6$$-216$$a=-6$$b=-216$\begin{align}G&amp;= \pm \sqrt{(-6)(-216)}= \pm \sqrt{1296} \\
\Rightarrow G&amp;= \pm 36\end{align}$$G=36 \quad \text{or} \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:30:01 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 Exercise 4.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-4-p6</link>
            <description>Question 9 Exercise 4.4

Solutions of Question 9 of Exercise 4.4 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 9(i)
$3 \dfrac{5}{9}=\dfrac{32}{9}\quad$$\quad40 \dfrac{1}{2}=\dfrac{81}{2}$$G_1, G_2, G_3, G_4$$G_5$$\dfrac{32}{9}$$\dfrac{81}{2}$$\dfrac{32}{9}, G_1, G_2, G_3, G_4, G_5, \dfrac{81}{2}$$a_7=\dfrac{81}{2}$$a_1=\dfrac{32}{9}$\begin{align}a_1 r^6&amp;=\dfra…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:30:03 +0000</pubDate>
        </item>
        <item>
            <title>Question 10 Exercise 4.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-4-p7</link>
            <description>Question 10 Exercise 4.4

Solutions of Question 10 of Exercise 4.4 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 10
$48$$18$$a$$b$$1$$48$$$\quad a-b=48....(i)$$$a$$b$$$G=\sqrt{a b}$$$a$$b$$$A=\dfrac{a+b}{2}$$$2$$A \cdot M=G \cdot M+18$$A \cdot M-G \cdot M=18$$$\Rightarrow \dfrac{a+b}{2}-\sqrt{a b}=18$$$$(a+b)-2 \sqrt{a b}=36 \text {. }$$$a=b+48$\begin{align}(b…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:30:03 +0000</pubDate>
        </item>
        <item>
            <title>Question 11 Exercise 4.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-4-p8</link>
            <description>Question 11 Exercise 4.4

Solutions of Question 11 of Exercise 4.4 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 11
$\mathrm{n}$$a$$b$$nth$$G_1, G_2, G_9, \ldots, G_n$$n$$a$$b$$a, G_1, G_2, G_3, \ldots, G_n, b$$n+2$$a_{n+2}=b$$a_n=a_1 r^{n-1}$$n$$n+2$\begin{align}a_{n+2}&amp;=a_1 r^{n i 1}=a r^{n+1}=b \\
\because a_1&amp;=a \\
\Rightarrow \quad r^{n+1}&amp;=\dfrac{b}{a} .…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:30:05 +0000</pubDate>
        </item>
        <item>
            <title>Question 12 Exercise 4.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-4-p9</link>
            <description>Question 12 Exercise 4.4

Solutions of Question 12 of Exercise 4.4 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 12
$n, . \dfrac{a^{n+1}+b^{n+1}}{a^n+b^n}$$a$$b$$a$$b$$\dfrac{a^{n+1}+b^{n-1}}{a^n+b^n}$$a$$b$\begin{align}\dfrac{a^{n+1}+b^{n+1}}{a^n+b^n}&amp;=\sqrt{a b}\quad \because G \cdot M=\sqrt{a b} \\
\Rightarrow \dfrac{a^{n+1}+b^{n+1}}{a^n+b^n}&amp;=a^{\dfrac{1}{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:30:05 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 Exercise 4.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-5-p1</link>
            <description>Question 1 Exercise 4.5

Solutions of Question 1 of Exercise 4.5 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 1(i)
$3+6+12+\ldots+3.2^9$$a_1=3, \quad r=\dfrac{6}{3}=2$$a_n=3.2^9$$n$$$a_n=a_1 r^{n-1}$$\begin{align}3.2^9&amp;=3(2)^{n-1} \text { or }(2)^{n-1}=\dfrac{3.2^9}{3} \\
\Rightarrow(2)^{n-1}&amp;=2^9 \\
\Rightarrow n-1&amp;=9 \text { or } n=10  \\
\text {. Now }\qua…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:30:06 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 Exercise 4.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-5-p2</link>
            <description>Question 2 Exercise 4.5

Solutions of Question 2 of Exercise 4.5 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 2(i)
$a_1, a_n, n_2 r$$S_n$$a_1=1, \quad r=-2, \quad a_n=64$$n$$S_n$$a_n=a_1 r^{n-1}$\begin{align}64&amp;=(-2)^{n-1}\\
\Rightarrow(-2)^{n-1}&amp;=(-2)^6 \\
\Rightarrow n-1&amp;=6 \\
\Rightarrow n&amp;=7\\
S_7&amp;=\dfrac{a_1[r^{\prime \prime}-1]}{r-1}\\
\text{then}\\
S_7…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:30:08 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 Exercise 4.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-5-p3</link>
            <description>Question 3 Exercise 4.5

Solutions of Question 3 of Exercise 4.5 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 3
$a_2=2$$a_3=1$$a_1$$r$$$a_n=a_1 r^{n-1}$$$$a_2=a_1 r=2....(i)$$$$a_3=a_1 r^2=1...(ii)$$\begin{align}\dfrac{a_1 r^2}{a_1 r}&amp;=\dfrac{1}{2}\\
\Rightarrow r&amp;=\dfrac{1}{2} \text {, }\end{align}\begin{align}\dfrac{a_1}{2}&amp;=2\\
\Rightarrow a_1&amp;=4 \text {. …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:30:08 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 Exercise 4.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-5-p4</link>
            <description>Question 4 Exercise 4.5

Solutions of Question 4 of Exercise 4.5 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 4(i)
$0 . \overline{8}$$$0 . \overline{8}=0.888888 \ldots$$\begin{align}0 . \overline{8}&amp;=0.8+0.08+0.008 \div 0.0008+ \ldots\\
\text { or } 0 . \overline{8}&amp;=0.8+(0.1)(0.8) +(0.1)^2(0.8)+\ldots \ldots \ldots \ldots .(\mathrm{i})\end{align}$$a_1=0.8, \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:30:10 +0000</pubDate>
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        <item>
            <title>Question 5 &amp; 6 Exercise 4.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-5-p5</link>
            <description>Question 5 &amp; 6 Exercise 4.5

Solutions of Question 5 &amp; 6 of Exercise 4.5 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 5
$r$$S_{10}=244 S_5$$$S_n=\dfrac{a_1(r^n-1)}{r-1}$$$$S_{10}=\dfrac{a_1(r^{10}-1)}{r-1} \quad \text{and}\quad S_5=\dfrac{a_1(r^5-1)}{r-1}$$$S_{10}$$S_S$\begin{align}\dfrac{a_1(r^{10}-1)}{r-1}&amp;=244 \dfrac{a_1(r^5-1)}{r-1} \\
\Rightarrow r^{10}-…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:30:10 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 &amp; 8 Exercise 4.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-5-p6</link>
            <description>Question 7 &amp; 8 Exercise 4.5

Solutions of Question 7 &amp; 8 of Exercise 4.5 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 7
$\operatorname{sum} S_n$$n$$\{(\dfrac{1}{2})^n\}$$$\{(\dfrac{1}{2})^n\}=\dfrac{1}{2}, \dfrac{1}{2^2}, \dfrac{1}{2^3}, \ldots$$$$a_1=\dfrac{1}{2}$$$$r=\dfrac{\dfrac{1}{2^2}}{\dfrac{1}{2}}=\dfrac{1}{2}$$\begin{align}S_n&amp;=\dfrac{a_1(1-r^n)}{1-r…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:30:12 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 &amp; 10 Exercise 4.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-5-p7</link>
            <description>Question 9 &amp; 10 Exercise 4.5

Solutions of Question 9 &amp; 10 of Exercise 4.5 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 9
$9$$n$$r$$a_1$$$S_n=\dfrac{a_1[r^n-1]}{r-1}$$$$S_6=\dfrac{a_1(r^5-1)}{r-1}$$$$S_3=\dfrac{a_1(r^3-1)}{r-1} \text {. }$$$3$$9$$6$\begin{align} \dfrac{a_1(r^6-1)}{r-1}&amp;=9 \dfrac{a_1(r^3-1)}{r-1} \\
\Rightarrow r^6-1-9(r^3-1) \\
\Rightarrow r^…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:30:12 +0000</pubDate>
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        <item>
            <title>Question 11 &amp; 12 Exercise 4.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-5-p8</link>
            <description>Question 11 &amp; 12 Exercise 4.5

Solutions of Question 11 &amp; 12 of Exercise 4.5 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$p^{t h}, q^{t h}$$r^{t h}$$a, b, c$$a^{q-r} b^{r-p} c^{p-q}=1$$a_n=a_1 r^{n-1}$$a_p=a_1 r^{p-1}=a \quad a_q=a_1 r^{q-1}=b$$a_r=a_1 r^{r-1}$\begin{align}a^{q-r}&amp;=(a_1 r^{p-1})^{q-r} . \\
b^{r-p}&amp;=(a_1 r^{q-1})^{r-p}, \text { and } \\
c^{p-q}&amp;=(a_1 r^…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:30:14 +0000</pubDate>
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        <item>
            <title>Question 13 &amp; 14 Exercise 4.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-5-p9</link>
            <description>Question 13 &amp; 14 Exercise 4.5

Solutions of Question 13 &amp; 14 of Exercise 4.5 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$y=\dfrac{x}{3}+\dfrac{x^2}{3^2}+\dfrac{x^3}{3^3}+\ldots$$0&lt;x&lt;3$$x=\dfrac{3 y}{1+y}$$$1+y=1+\dfrac{x}{3}+\dfrac{x^2}{3^2}+\dfrac{x^3}{3^3}$$$a_1=1$$r=\dfrac{x}{3}$$|r|=\dfrac{x}{3}&lt;1$$0&lt;x&lt;3$$S_{\infty}=\dfrac{a_1}{1-r}$$a_1, \quad r$$$S_{\infty}=\dfr…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:30:14 +0000</pubDate>
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        <item>
            <title>Question 15 &amp; 16 Exercise 4.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-5-p10</link>
            <description>Question 15 &amp; 16 Exercise 4.5

Solutions of Question 15 &amp; 16 of Exercise 4.5 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$2$$4$$15^{\text {th }}$$a_1=R s .1$$a_2=R s .2$$a_3=R s .4$$1,2,4,8, \ldots$$a_1=1 . \quad r=2 . \quad n=15$$a_n=a_1 r^{n-1}$$15^{1 / 2}$$$a_{15}=a_1 r^{14} $$$$a_{15}=1 .(2)^{1 4}=R s .16384 $$$$S_{30}=\dfrac{a_1(r^{30}-1)}{r-1} $$$r-2$$a_1=1$\begi…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:30:06 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 Exercise 5.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/ex5-1-p1</link>
            <description>Question 1 Exercise 5.1

Solutions of Question 1 of Exercise 5.1 of Unit 05: Mascellaneous series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 1(i)
$1^2+3^2+5^2+7^2+\ldots$$n$$1+3+5+\ldots$$n^{\text {th }}$$2 n-1$$n^{t h}$$$T_j=(2 j-1)^2$$\begin{align}&amp; \sum_{j=1}^n T_j=\sum_{j=1}^n(2 j-1)^2 \\
&amp; =\sum_{j=1}^n(4 j^2-4 j+1)\\
&amp; =4 \sum_{j=1}^n j^2-4 \sum_{j=1}^n j+\sum_{j=1}^n 1 \\
&amp; =4 \dfr…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:10 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 &amp; 3 Exercise 5.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/ex5-1-p2</link>
            <description>Question 2 &amp; 3 Exercise 5.1

Solutions of Question 2 &amp; 3 of Exercise 5.1 of Unit 05: Miscullaneous Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Q2 Find the sum $1.2+2.3+3.4+\ldots+99.100$$1+2+3+\ldots+99$$2+3+4+\ldots+100$$n^{\text {th }}$$n(n+1)$$n^{\text {th }}$$\quad T_j=j(j+1)=j^2+j$$j=1$$j=99$$$
\begin{aligned}
&amp; \sum_{j=1}^{99} \tau_j=\sum_{j=1}^{99} j^2+\sum_{j=1}^{99} j \\
&amp; =\frac{99…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:10 +0000</pubDate>
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        <item>
            <title>Question 4 &amp; 5 Exercise 5.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/ex5-1-p3</link>
            <description>Question 4 &amp; 5 Exercise 5.1

Solutions of Question 4 &amp; 5 of Exercise 5.1 of Unit 05: Miscullaneous Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 4
$2+(2+5)+(2+5+8)+\ldots$$n$\begin{align}&amp; T_j=\dfrac{j}{2}[2(2)+3(j-1)]\\
&amp;=\dfrac{j(3 j+1)}{2} \\
&amp; =\dfrac{1}{2}(3 j^2+j)\end{align}\begin{align}&amp; \sum_{j=1}^n T_i=\dfrac{1}{2}[3 \sum_{j=1}^n j^2+\sum_{j=1}^n j] \\
&amp; =\dfrac{1}{2}[3 \dfra…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:11 +0000</pubDate>
        </item>
        <item>
            <title>Question 6 Exercise 5.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/ex5-1-p4</link>
            <description>Question 6 Exercise 5.1

Solutions of Question 6 of Exercise 5.1 of Unit 05: Miscullaneous Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 6
$1.2 \cdot 3+2 \cdot 3.4+3.4 .5+\ldots$$n$$1+2+3+\ldots, \quad 2+3+4+5+\ldots$$3+4+5+6+7+\ldots$$n^{t h}$$j, j+1$$j+2$$n^{t h}$\begin{align}
&amp; T_j=j(j+1)(j+2)-j(j^2+3 j+2) \\
&amp; =j^3+3 j^2+2 j\end{align}\begin{align}
&amp; \sum_{j=1}^n T_j=\sum_{j=1}^n …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:12 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 &amp; 8 Exercise 5.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/ex5-1-p5</link>
            <description>Question 7 &amp; 8 Exercise 5.1

Solutions of Question 7 &amp; 8 of Exercise 5.1 of Unit 05: Miscullaneous Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 7
$n$$1.5 .9+2.6 .10+3.7 .11+\ldots$$T_j=j(j+4)(j+8)$\begin{align}
&amp; =j(j^2+12 j+32) \\
&amp; =j^3+12 j^2+32 j\end{align}\begin{align}
&amp; \sum_{j=1}^n T_j=\sum_{j=1}^n j^3+12 \sum_{j=1}^n j^2+32 \sum_{j=1}^n j \\
&amp; =(\dfrac{n(n+1)}{2})^2+12 \dfrac…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:13 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 Exercise 5.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/ex5-1-p6</link>
            <description>Question 9 Exercise 5.1

Solutions of Question 9 of Exercise 5.1 of Unit 05: Miscullaneous Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 9(i)
$n$$n$$n$\begin{align}
&amp; T_n=n^2(2 n+3)=2 n^3+3 n^2 \\
&amp; \Rightarrow T_j=2 j^3+3 j^2\end{align}\begin{align}
&amp; \sum_{j=1}^n T_j=2 \sum_{j=1}^n j^3+3 \sum_{j=1}^n j^2 \\
&amp; =2(\dfrac{n(n+1)}{2})^2+3 \dfrac{n(n+1)(2 n+1)}{6} \\
&amp; =\dfrac{n(n+1)}{2}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:13 +0000</pubDate>
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        <item>
            <title>Question 1 Exercise 5.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/ex5-2-p1</link>
            <description>Question 1 Exercise 5.2

Solutions of Question 1 of Exercise 5.2 of Unit 05: Mascellaneous series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 1(i)
$n$$1.2+2.2^2+3.2^3+4.2^4+\ldots$\begin{align}
&amp; S_n=1.2+2.2^2+3 \cdot 2^3+4 \cdot 2^4+\ldots +n \cdot 2^n....(i) \\
&amp; 2 S_n=1.2^2+2.2^3+3.2^4+4.2^5+\ldots +n \cdot 2^n....(ii)\end{align}\begin{align} (1-2) S_n&amp;=1 \cdot 2+(2-1) 2^2+(3-2) 2^2+(4-…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:14 +0000</pubDate>
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        <item>
            <title>Question 2 &amp; 3 Exercise 5.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/ex5-2-p2</link>
            <description>Question 2 &amp; 3 Exercise 5.2

Solutions of Question 2 &amp; 3 of Exercise 5.2 of Unit 05: Miscullaneous Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 2
$1+3^2 x+5^2 x^2+7^2 x^3+\ldots, x&lt;1$\begin{align}
&amp; S_{\infty}=1+3^2 x+5^2 x^2+7^2 x^3+\ldots ..(1)\\
&amp; x S_{\infty}=x+3^2 x^2+5^2 x^3+7^2 x^4+\ldots..(2)\end{align}\begin{align}&amp; (1-x) S_{\infty}=1^2+(3^2-1^2) x+(5^2-3^2) x^2+(7^2-5^2) x^…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:14 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 &amp; 5 Exercise 5.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/ex5-2-p3</link>
            <description>Question 4 &amp; 5 Exercise 5.2

Solutions of Question 4 &amp; 5 of Exercise 5.2 of Unit 05: Miscullaneous Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 4
$5+\dfrac{7}{3}+\dfrac{9}{3^2}+\dfrac{11}{3^3}+\ldots$\begin{align}
&amp; S_{\infty}=5+\dfrac{7}{3}+\dfrac{9}{3^2}+\dfrac{11}{3^3}+\ldots.(i) \\
&amp; \dfrac{1}{3} S_{\infty}=\dfrac{5}{3}+\dfrac{7}{3^2}+\dfrac{9}{3^2}+\dfrac{11}{3^3}+\ldots.(ii)
\e…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:15 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 Exercise 5.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/ex5-3-p1</link>
            <description>Question 1 Exercise 5.3

Solutions of Question 1 of Exercise 5.3 of Unit 05: Mascellaneous series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 1
$n$$n$$4+13+28+49+76+\ldots$\begin{align}
&amp; a_2-a_1=13-4=9 \\
&amp; a_3-a_2=28-13=15 \\
&amp; a_4-a_3=49-28=21 \\
&amp; \cdots \quad \cdots \quad \cdots \\
&amp; \cdots \quad \cdots \quad \cdots \\
&amp; a_n-a_{n-1}=(n-1)th \quad\text{term of sequence}\quad 9,15,21,..…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:16 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 Exercise 5.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/ex5-3-p2</link>
            <description>Question 2 Exercise 5.3

Solutions of Question 2 of Exercise 5.3 of Unit 05: Miscullaneous Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 2
$n$$n$$4+14+30+52+80+114+\ldots$\begin{align}
&amp; a_2-a_1=14-4=10 \\
&amp; a_3-a_2=30-14=16 \\
&amp; a_4-a_3=52-30=22 \\
&amp; \cdots \quad \cdots \quad \cdots \\
&amp; \cdots \quad \cdots \quad \cdots \\
&amp; a_n-a_{n-1}=(\mathrm{n}-1)\text{ term of the sequence} 10,1…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:17 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 Exercise 5.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/ex5-3-p3</link>
            <description>Question 3 Exercise 5.3

Solutions of Question 3 of Exercise 5.3 of Unit 05: Miscullaneous Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 3
$n$$n$$4+10+18+28+40+\ldots$\begin{align}
&amp; a_2-a_1=10-4=6 \\
&amp; a_3-a_2=18-10=8 \\
&amp; a_4-a_3=28-18=10 \\
&amp; \text {... ... ... } \\
&amp; \text {... ... ... } \\
&amp; a_n-a_{n \quad 1}=(\mathrm{n}-1) \text { term of the sequence } \end{align}$6,10,8, \ldot…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:17 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 Exercise 5.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/ex5-3-p4</link>
            <description>Question 4 Exercise 5.3

Solutions of Question 4 of Exercise 5.3 of Unit 05: Miscullaneous Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 4
$n$$n$$3+5+11+29+83+245+\ldots$\begin{align}
&amp; a_2-a_1=5-3=2 \\
&amp; a_3-a_2=11-5=6 \\
&amp; a_4-a_3=29-11=18 \\
&amp; \text {... ... ... } \\
&amp; \text {... ... ... } \\
&amp; a_n-a_{n-1}=(\mathrm{n}-1) \text { term ofthe sequence }\end{align}$6,10,18, \ldots$\beg…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:18 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 Exercise 5.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/ex5-3-p5</link>
            <description>Question 5 Exercise 5.3

Solutions of Question 5 of Exercise 5.3 of Unit 05: Miscullaneous Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 5
$n$$n$$3+9+21+45+93+189+\ldots$\begin{align}
&amp; a_2-a_1=9-3=6 \\
&amp; a_3-a_2=21-9=12 \\
&amp; a_4-a_3=45-21=24\\
&amp; \text {... ... ... } \\
&amp; \text {... ... ... } \\
&amp;a_n-a_{n-1}=(\mathrm{n}-1)\quad \text{ term of the sequence}\quad 6,12,24, \ldots\end{ali…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:19 +0000</pubDate>
        </item>
        <item>
            <title>Question 6 Exercise 5.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/ex5-3-p6</link>
            <description>Question 6 Exercise 5.3

Solutions of Question 6 of Exercise 5.3 of Unit 05: Miscullaneous Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 6
$n$$n$$28+32+52+152+652+\ldots$\begin{align}
&amp; a_2-a_1=32-28=4 \\
&amp; a_3-a_2=52-32=20 \\
&amp; a_4-a_3=152-52=100 \\
&amp; \ldots \quad \cdots \quad \cdots \\
&amp; \cdots \quad \cdots \quad \cdots \\
&amp; a_n-a_{n-1}=(\mathrm{n}-1) \text { term ofthe sequence } 4…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:20 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 Exercise 5.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/ex5-4-p1</link>
            <description>Question 1 Exercise 5.3

Solutions of Question 1 of Exercise 5.4 of Unit 05: Mascellaneous series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 1(i)
$\dfrac{1}{1.2}+\dfrac{1}{2.3}+\dfrac{1}{3.4}+\ldots$$n$$$T_n=\dfrac{1}{n(n+1)}$$$T_n$$$\dfrac{1}{n(n+1)}=\dfrac{A}{n}+\dfrac{B}{(n+1)}$$$n(n+1)$$$1=A(n+1)+B n=(A+B) n+A$$$n$$$A+B=0 \text{and} A=1$$$A=1$\begin{align}1+B&amp;=0\\
B&amp;=-1\end{align}\beg…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:20 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 &amp; 3 Exercise 5.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/ex5-4-p2</link>
            <description>Question 2 &amp; 3 Exercise 5.4

Solutions of Question 2 &amp; 3 of Exercise 5.4 of Unit 05: Miscullaneous Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 2
$\sum_{k=1}^n \dfrac{1}{9 k^2+3 k-2}$\begin{align}\text { Let } S_n&amp;=\sum_{k=1}^n \dfrac{1}{9 k^2+3 k-2} \\
S_n&amp;=\sum_{k=1}^n \dfrac{1}{9 k^2+6 k-3 k-2} \\
&amp; =\sum_{k=1}^n \dfrac{1}{3 k(3 k+2)-1(3 k+2)} \\
S_n&amp;=\sum_{k=1}^n \dfrac{1}{(3 k-1…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:21 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 Exercise 5.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/ex5-4-p3</link>
            <description>Question 4 Exercise 5.4

Solutions of Question 4 of Exercise 5.4 of Unit 05: Miscullaneous Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 4
$\sum_{k=1}^n \dfrac{1}{k^2+7 k+12}$\begin{align}S_n &amp;=\sum_{k=1}^n \dfrac{1}{k^2+7 k+12} \\
&amp; =\sum_{k=1}^n \dfrac{1}{(k+3)(k+4)}\end{align}$n^{\text {th }}$$$u_n=\dfrac{1}{(n+3)(n+4)}$$$$\dfrac{1}{(n+3)(n+4)}=\dfrac{A}{n+3}+\dfrac{B}{n+4}$$$A$$B$…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:21 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 Review Exercise 5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/re-ex5-p1</link>
            <description>Question 1 Review Exercise 5

Solutions of Question 1 of Review Exercise 5 of Unit 05: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 1

$t_n=6 n+5$$t_{n+1}=$$6 n-1$$6 n+11$$6 n+6$$6 n-5$$6 n+11$$1+\dfrac{2}{3}+\dfrac{6}{3^2}+\dfrac{10}{3^3}+\dfrac{14}{3^4}+\ldots$$6$$2$$3$$4$$3$$1+2.2+3.2^2+\cdots+100.2^{\prime \prime}$$99.2^{100}$$100.2^{100}$$99.2^{100}+1$$1000.2^{100}$$99.2^{100}+…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:22 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 &amp; 3 Review Exercise</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/re-ex5-p2</link>
            <description>Question 2 &amp; 3 Review Exercise

Solutions of Question 2 &amp; 3 of Review Exercise of Unit 05: Miscullaneous Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$n$$1.2+2.3+3.4+\ldots$$n^{\text {th }}$$$a_n=n(n+1)=n^2+n$$\begin{align}
\sum_{r=1}^n a_r&amp;=\sum_{r=1}^n r^2+\sum_{r=1}^n r \\
&amp; =\dfrac{n(n+1)(2 n+1)}{6}+\dfrac{n(n+1)}{2} \\
&amp; =\dfrac{n(n+1)}{2}[\dfrac{2 n+1}{3}+1] \\
&amp; =\dfrac{n(n+1)}{2} \cdot …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:23 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 Review Exercise</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/re-ex5-p3</link>
            <description>Question 4 Review Exercise

Solutions of Question 4 of Review Exercise of Unit 05: Miscullaneous Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 4
$\dfrac{1}{1.4 .7}+\dfrac{1}{4.7 .10}+\dfrac{1}{7.10 .13}+\ldots$$1,4,7, \ldots$$$a_n=\dfrac{1}{(3 n-2)(3 n+1)(3 n+4)}$$\begin{align}
\dfrac{1}{(3 n-2)(3 n+1)(3 n+4)}&amp;=\dfrac{A}{3 n-2}+\dfrac{B}{3 n+1}+\dfrac{C}{3 n+4}\end{align}$(3 n-2)(3 n+…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:24 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 &amp; 6 Review Exercise</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/re-ex5-p4</link>
            <description>Question 5 &amp; 6 Review Exercise

Solutions of Question 5 &amp; 6 of Review Exercise of Unit 05: Miscullaneous Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$5+12 x+19 x^2+26 x^3+\ldots$$n$\begin{align}S_n&amp;=5+12 x+19 x^2+26 x^3+\cdots+(7 n-2) x^{n-1}...(i)\\ 
x S_n&amp;=5 x+12 x^2+19 x^3+\cdots+(7 n-9) x^{n-1}+(7 n-1) x^n....(ii)\end{align}\begin{align}(1-x) S_n&amp;=5+(12-5) x+(19-12) x^2+\cdots\\
&amp;+[7 n-2-(…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:24 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 Review Exercise</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/re-ex5-p5</link>
            <description>Question 7 Review Exercise

Solutions of Question 7 of Review Exercise of Unit 05: Miscullaneous Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 7(i)
$1.2^2+3.3^2+5.4^2+\ldots$$n$$1,3,5, \ldots,(2 n-1)$$2^2, 3^2, 4^2, \ldots,(n+1)^2$\begin{align}
&amp; a_n=(2 n-1)(n+1)^2 \\
&amp; a_n=(2 n-1)(n^2+2 n+1) \\
&amp; a_n=2 n^3+3 n^2-1\end{align}\begin{align}
\sum_{r=1}^n a_r&amp;=2 \sum_{r=1}^n r^3+\sum_{r=1…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:25 +0000</pubDate>
        </item>
        <item>
            <title>Question 8 Review Exercise</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/re-ex5-p6</link>
            <description>Question 8 Review Exercise

Solutions of Question 8 of Review Exercise of Unit 05: Miscullaneous Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 8(i)
$n$$n^{t h}$$n^3+3^n.$$n^h$$$a_n=n^3+3^n$$\begin{align}\sum_{r=1}^n a_r&amp;=\sum_{r=1}^n r^3+\sum_{r=1}^n 3^r \\
&amp; =[\dfrac{n(n+1)}{2}]^2+\dfrac{3(3^n-1)}{3-1} \\
&amp; =\dfrac{n^2(n+1)^2}{4}+\dfrac{3}{2}(3^n-1) \end{align}$n$$$S_n=\dfrac{n^2(n+1…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:25 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 Review Exercise</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/re-ex5-p7</link>
            <description>Question 9 Review Exercise

Solutions of Question 9 of Review Exercise of Unit 05: Miscullaneous Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 9(i)
$n$$3+7+13+21+31+\ldots$\begin{align}
&amp; a_2-a_1=7-3=4 \\
&amp; a_3-a_2=13-7=6 \\
&amp; a_4-a_3=21-13=8 \\
&amp; \ldots \quad \ldots \quad \ldots \\
&amp; \ldots \quad \cdots \quad \ldots \\
&amp; a_n-a_{n-1}=(n-1) \text { term of the series } \\
&amp; 4,6,8, \ldo…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:26 +0000</pubDate>
        </item>
        <item>
            <title>Question 10 Review Exercise</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/re-ex5-p8</link>
            <description>Question 10 Review Exercise

Solutions of Question 10 of Review Exercise of Unit 05: Miscullaneous Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.

Question 10
$n^{\text {th }}$$n$$1+(1+\dfrac{1}{2})+(1+\dfrac{1}{2}+\dfrac{1}{4})+(1+\dfrac{1}{2}+\dfrac{1}{4}+\dfrac{1}{8})+\ldots$\begin{align}
a_n&amp;=1+\dfrac{1}{2}+\dfrac{1}{4}+\dfrac{1}{8}+\cdots+\dfrac{1}{2^{n-1}} \\
a_n&amp;=\dfrac{1[1-(\dfrac{1}{2})…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:26 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 and 2 Exercise 6.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-1-p1</link>
            <description>Question 1 and 2 Exercise 6.1

Solutions of Question 1 and 2 of Exercise 6.1 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\dfrac{10 !}{3 ! .3 ! \cdot 4 !}$\begin{align}\dfrac{10 !}{3 ! \cdot 3 ! \cdot 4 !}&amp;=\dfrac{10.9 .8 \cdot 7 \cdot 6 \cdot 5.4 !}{3 ! \cdot 3 ! \cdot 4 !}\\
&amp;=\dfrac{10.9 .8 .7 .5}{3.2 .1}\\
&amp;=4200 \end{align}$\dfrac{3 !+4 !}{5 !-…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:32 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 &amp; 4 Exercise 6.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-1-p2</link>
            <description>Question 3 &amp; 4 Exercise 6.1

Solutions of Question 3 &amp; 4 of Exercise 6.1 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\dfrac{1}{6 !}+\dfrac{2}{7 !}+\dfrac{3}{8 !}=\dfrac{75}{8 !}$\begin{align}\dfrac{1}{6 !}+\dfrac{2}{7 !}+\dfrac{3}{8 !}&amp;=\dfrac{1}{6 !}+\dfrac{2}{7.6 !}+\dfrac{3}{8.7 .6 !} \\
&amp; =\dfrac{56+16+3}{8 !}\\
&amp;=\dfrac{75}{8 !}\end{align}$\df…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:30 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 Exercise 6.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-1-p3</link>
            <description>Question 5 Exercise 6.1

Solutions of Question 5 of Exercise 6.1 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\dfrac{(2 n) !}{n !}=2^n(1.3 .5 \ldots(2 n-1))$\begin{align}\dfrac{(2 n) !}{n !}&amp;=\dfrac{1}{n !}[(2 n)(2 n-1)(2 n-2) \\
&amp;=(2 n-3)(2 n-4)(2 n-5) \ldots(2 n-(2 n-4))\\
&amp;(2 n-(2 n-3))(2 n-(2 n-2))(2 n-(2 n-1))]\end{align}$2 n$\begin{align}\dfra…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:32 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 Exercise 6.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-1-p4</link>
            <description>Question 4 Exercise 6.1

Solutions of Question 4 of Exercise 6.1 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:33 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 Exercise 6.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-1-p5</link>
            <description>Question 5 Exercise 6.1

Solutions of Question 5 of Exercise 6.1 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:33 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 and 2 Exercise 6.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-2-p1</link>
            <description>Question 1 and 2 Exercise 6.2

Solutions of Question 1 and 2 of Exercise 6.2 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$^6 P_6$\begin{align}^6 P_6&amp;=\dfrac{6 !}{(6-6) !}\\
&amp;=6 !=720\end{align}$^{20} P_2$\begin{align}^{20} P_2&amp;=\dfrac{20 !}{(20-2) !}\\
&amp;=\dfrac{20.19 .18 !}{18 !}\\
&amp;=20 \times 19=380\end{align}$^{16} P_3$\begin{align}^{16} P_3&amp;=\dfr…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:35 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 and 4 Exercise 6.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-2-p2</link>
            <description>Question 3 and 4 Exercise 6.2

Solutions of Question 3 and 4 of Exercise 6.2 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$^n P_r=n(^{n-1} P_{r-1})$$$^n P_r=n({ }^{n-1} P_{r-1})$$\begin{align}n(^{n-1} P_{r-1})&amp;=n \dfrac{(n-1) !}{((n-1)-(r-1)) !} \\
&amp; =\dfrac{n(n-1) !}{(n-r) !}\\
&amp;=\dfrac{n !}{(n-r) !}\\
&amp;=^n P_r\end{align}$^n P_r=^{n-1} P_r+r(^{n-1} …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:37 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 and 6 Exercise 6.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-2-p3</link>
            <description>Question 5 and 6 Exercise 6.2

Solutions of Question 5 and 6 of Exercise 6.2 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$7.$$7$$7$\begin{align}^7 P_7&amp;=\dfrac{7 !}{(7-7) !}\\
&amp; =7 !\\
&amp;=5,040 \end{align}$2,4,5,7,9$$2,4,5,7,9$$\mathrm{n} . \mathrm{m}$$e$$$=5.4 .3 .2=120\quad \text{or}$$$$^5 P_4=\dfrac{5 !}{5-4} !=120$$$2$$4$$3$$E_1$$m_1=2$$E_2$$m_2=3…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:36 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 and 8 Exercise 6.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-2-p4</link>
            <description>Question 7 and 8 Exercise 6.2

Solutions of Question 7 and 8 of Exercise 6.2 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$1,2,3,4$$E_1$$m_1=5$$E_2$$\cdot m_2=5$$E_3$$m_3=5$$$m_1 \cdot m_2 \cdot m_3=5.5 \cdot 5=125$$$1,2,3,4$$E_1$$m_1=5$$E_2$$m_2=4$$E_3$$m_3=3$$$m_1 \cdot m_2 \cdot m_3=5 \cdot 4 \cdot 3=60$$$8$$5$$=4$$=4$$=5$$=3$$4 ! \cdot 5 ! \cdot …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:38 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 Exercise 6.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-2-p5</link>
            <description>Question 9 Exercise 6.2

Solutions of Question 9 of Exercise 6.2 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$=^6 P_1=6$$s=^6 P_2=30$$=^6 P_3=120$$=^6 P_4=360$$=^6 P_5=720$$=^6 P_6=720$$6+30+120+360+720+720=1956$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:38 +0000</pubDate>
        </item>
        <item>
            <title>Question 10 Exercise 6.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-2-p6</link>
            <description>Question 10 Exercise 6.2

Solutions of Question 10 of Exercise 6.2 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$n=8$$r=5$\begin{align}^8 P_5&amp;=\dfrac{8 !}{(8-5) !}\\
&amp;=\dfrac{8 \cdot 7 \cdot 6 \cdot 5 \cdot 4 \cdot 3 !}{3 !}\\
&amp;=6720\end{align}\begin{align}^2 P_2 \times^7 P_4&amp;=2 \times \dfrac{7 !}{(7-4) !}\\
&amp;=2 \times\dfrac{7.6 .5 .4 .3 !}{3 !}\\
&amp;=…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:40 +0000</pubDate>
        </item>
        <item>
            <title>Question 11 Exercise 6.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-2-p7</link>
            <description>Question 11 Exercise 6.2

Solutions of Question 11 of Exercise 6.2 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$10$$1000$$2.3,4,0,8,9$$10$$1000$$10$$100$$E_1$$m_1=5$$E_2$$m_2=5$$10$$100$$$m_1 \cdot m_2=5.5=25$$$100$$1000$$0$$E_1$$m_1=5$$E_2$$\boldsymbol{m}_2=5$$E_3$$m_3=4$$100$$1000$$$m_1 \cdot m_2 \cdot m_3=5.5 \cdot 4=100$$$10$$1000$$$100 + 25=125…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:40 +0000</pubDate>
        </item>
        <item>
            <title>Question 12 Exercise 6.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-2-p8</link>
            <description>Question 12 Exercise 6.2

Solutions of Question 12 of Exercise 6.2 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$8.$$n=8$$\mathrm{O}$$m_1=3$\begin{align}
 \left(\begin{array}{c}
n \\
m 1
\end{array}\right)&amp;=\left(\begin{array}{l}
8 \\
3
\end{array}\right) \\
&amp; =\dfrac{8 !}{3 !}\\
&amp;=\dfrac{8 \cdot 7 \cdot 6 \cdot 5 \cdot 4 \cdot 3 !}{3 !}\\
&amp;=6,720 \e…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:41 +0000</pubDate>
        </item>
        <item>
            <title>Question 13 Exercise 6.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-2-p9</link>
            <description>Question 13 Exercise 6.2

Solutions of Question 13 of Exercise 6.2 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\mathrm{E}$$n=10$$m_1=4$$E, m_2=2$$L$$m_3=2$$C$\begin{align}\text{total number of permutations are}
 &amp;=\left(\begin{array}{c}
n \\
m_1, m_2, m_3
\end{array}\right)\\&amp;=\left(\begin{array}{c}
10 \\
4,2,2
\end{array}\right) \\
&amp; =\dfrac{10 !}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:41 +0000</pubDate>
        </item>
        <item>
            <title>Question 14 and 15 Exercise 6.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-2-p10</link>
            <description>Question 14 and 15 Exercise 6.2

Solutions of Question 14 and 15 of Exercise 6.2 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$$\dfrac{(n-1) !}{2}=\dfrac{(5-1) !}{2}=\dfrac{24}{2}=12 $$$7$$7$$6 !$$6$$5!$$2 !=2$$7$$$2 \times 5 !=240$$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:35 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 Exercise 6.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-3-p1</link>
            <description>Question 1 Exercise 6.3

Solutions of Question 1 of Exercise 6.3 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$^n C_2=36$$n$\begin{align}&amp;^n C_2=36\\
&amp; \Rightarrow \dfrac{n !}{(n-2) ! 2 !}=36 \\
&amp; \Rightarrow \dfrac{n(n-1)(n-2) !}{(n-2) ! \cdot 2}=36 \\
&amp; \Rightarrow n(n-1)=72 \\
&amp; \Rightarrow n^2-n-72=0 \\
&amp; \Rightarrow n^2-9 n+8 n-72=0\\
&amp; \Rightar…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:43 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 Exercise 6.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-3-p2</link>
            <description>Question 2 Exercise 6.3

Solutions of Question 2 of Exercise 6.3 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$n$$r$${ }^n P_r=840$${ }^n C_r=35$\begin{align}
&amp;^n P_r=\dfrac{n !}{(n-r) !}=840 ....(i)\\
&amp;^n C_r=\dfrac{n !}{(n-r) ! r !}=35....(ii)\end{align}\begin{align}\dfrac{n !}{(n-r) !} \cdot \dfrac{(n-r) ! r !}{n !}&amp;=\dfrac{840}{35}\\
r!&amp;=24\\
\te…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:43 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 Exercise 6.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-3-p3</link>
            <description>Question 3 Exercise 6.3

Solutions of Question 3 of Exercise 6.3 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$n$$^{2 n} C_3:^n C_2=36: 3$\begin{align}
&amp; { }^{2 n} C_3:{ }^n C_2=36: 3 . \\
&amp; \Rightarrow \dfrac{(2 n) !}{(2 n-3) ! 3 !} \times \dfrac{(n-2) ! 2 !}{n !}=12 \\
&amp; \Rightarrow \dfrac{2 n(2 n-1)(2 n-2)(2 n-3) !}{(2 n-3) ! 3 !}\times\dfrac{(n-2…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:45 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 Exercise 6.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-3-p4</link>
            <description>Question 4 Exercise 6.3

Solutions of Question 4 of Exercise 6.3 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.${ }^{n-1} C_r+{ }^{n-1} C_{r-1}={ }^n C_r$$${ }^n{ }^1 C_r+{ }^n{ }^1 C_{r-1}={ }^n C_s$$\begin{align}
{ }^{n-1} C_r+{ }^{n-1} C_{r-1}&amp;=\dfrac{(n-1) !}{(n-r-1) ! r !}+\dfrac{(n-1) !}{(n-1-(r-1)) !(r-1) !} \\
&amp; =\dfrac{(n-1) !}{(n-r-1) ! r(r-…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:46 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 and 6 Exercise 6.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-3-p5</link>
            <description>Question 5 and 6 Exercise 6.3

Solutions of Question 5 and 6 of Exercise 6.3 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$12$$n=12$${ }^{12} C_2=66$$12$$n=12$${ }^{12} C_3=220$$${ }^6 C_2=\dfrac{6 !}{(6-2) ! 2 !}=15 $$$6$$\quad 15-6=9$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:46 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 and 8 Exercise 6.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-3-p6</link>
            <description>Question 7 and 8 Exercise 6.3

Solutions of Question 7 and 8 of Exercise 6.3 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$20$\begin{align}{ }^{20} C_2&amp;=\dfrac{20 !}{(20-2)2!}!\\
&amp;=\dfrac{20!}{18!\cdot 2!}\\
&amp;=190\end{align}$7$$10$$3$$7$$10$$${ }^{10} C_7=\dfrac{10 !}{(10-7) ! 7 !}=120$$$7$$4.$$4$$${ }^7 C_4=\dfrac{7 !}{(7-4) ! 4 !}=35.$$$35$$10.$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:47 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 Exercise 6.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-3-p7</link>
            <description>Question 9 Exercise 6.3

Solutions of Question 9 of Exercise 6.3 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$8$$6$$7$$7$$6.$$=7+6=13$${ }^7 C_4$${ }^6 C_4$\begin{align}{ }^7 C_4 \cdot{ }^6 C_4&amp;=\dfrac{7 !}{(7-4) ! 4 !} \cdot \dfrac{6 !}{(6-4)}\\\
&amp;= 525\end{align}$8$$6$$7$$7$$6$$=7+6=13$$3,4,5,6$$6$\begin{align}{ }^7 C_2 \cdot{ }^6 C_6&amp;=\dfrac{7 !}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:48 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 Exercise 6.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-3-p8</link>
            <description>Question 9 Exercise 6.3

Solutions of Question 9 of Exercise 6.3 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:48 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 Exercise 6.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-4-p1</link>
            <description>Question 1 Exercise 6.4

Solutions of Question 1 of Exercise 6.4 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$S=\{1,2,3,4,5,6\}$$5$$5$\begin{align}A&amp;=\{5\}\\
P(A)&amp;=\dfrac{n(A)}{n(S)}\\
&amp;=\dfrac{1}{6} \end{align}$S=\{1,2,3,4,5,6\}$$1$$1$\begin{align}B&amp;=\{\}\\
&amp;=\phi \text{then}\\
P(B)&amp;=\dfrac{n(B)}{n(S)}\\
&amp;=\dfrac{0}{6}\\
&amp;=0\end{align}$S=\{1,2,3,4,…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:49 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 Exercise 6.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-4-p2</link>
            <description>Question 2 Exercise 6.4

Solutions of Question 2 of Exercise 6.4 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$4$$5$$6$$3$$4+5+6=15$$${ }^{15} C_3=\dfrac{15 !}{(15-3) ! 3 !}=455 $$$${ }^6 C_4=\dfrac{6 !}{(6-4) ! 4 !}=15$$$$=\dfrac{15}{455}=\dfrac{3}{91}$$$4$$5$$6$$3$$4+5+6=15$$${ }^{15} C_3=\dfrac{15 !}{(15-3) ! 3 !}=455 $$$${ }^4 C_3=\dfrac{4 !}{(4-…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:50 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 Exercise 6.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-4-p3</link>
            <description>Question 3 Exercise 6.4

Solutions of Question 3 of Exercise 6.4 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$8$$8$$2^8$$$n(S)=256$$$$\dfrac{1}{256}$$$8$$$A=\{8\}$$$${ }^8 C_8=\dfrac{8 !}{(8-8) ! 8 !}=1$$$8$$$P(A)=\dfrac{1}{256}$$$7$$8$$2^8$$$n(S)=256$$$$\dfrac{1}{256}$$$7$$$B=\{7\}$$$7$$8$$$n(B)={ }^8 C_7=\dfrac{8 !}{(8-7) ! 7 !}=8$$$7$$8$$$P(B)=\d…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:51 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 Exercise 6.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-4-p4</link>
            <description>Question 4 Exercise 6.4

Solutions of Question 4 of Exercise 6.4 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.\begin{align}S&amp;=(HHII,HHT.HTH.HTT.THII.THT.TTH,TT7),\\
\text{then} n(S)&amp;=2^3=8\end{align}$$A=\{H H H\}$$$$n(A)=1$$$P(A)=\dfrac{n(A)}{n(S)}=\dfrac{1}{8}$\begin{align}S&amp;=(HHII,HHT.HTH.HTT.THII.THT.TTH,TT7),\\ 
\text{then} n(S)&amp;=2^3=8\end{align}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:52 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 Exercise 6.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-4-p5</link>
            <description>Question 5 Exercise 6.4

Solutions of Question 5 of Exercise 6.4 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$6$$4$$3$$2$$=6+4=10$$5$$10$\begin{align}{ }^{10)} C_5 &amp;=\dfrac{10 !}{(10-5) ! 5 !}\\
&amp;=252\\ 
n(S)&amp;=252\end{align}$3$$2$$3$$2$\begin{align}{ }^6 \mathrm{C}_3\cdot{ }^{4} \mathrm{C}_2&amp;=\dfrac{6 !}{(6-3) ! 3 !} \cdot \dfrac{4 !}{(4-2) ! 2 !}\\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:52 +0000</pubDate>
        </item>
        <item>
            <title>Question 6 Exercise 6.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-4-p6</link>
            <description>Question 6 Exercise 6.4

Solutions of Question 6 of Exercise 6.4 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$52$$$=52$$$=4$$$=\dfrac{4}{52}=\dfrac{1}{13}$$$52$$=52$$13$$13$$$\dfrac{13}{52}+ \dfrac{13}{52}=\dfrac{1}{4}+\dfrac{1}{4}=\dfrac{2}{4}=\dfrac{1}{2}$$$52$$=52$$13.$$$=\dfrac{13}{52}=\dfrac{1}{4}$$$52$$=52$$12.$$$=\dfrac{12}{52}=\dfrac{3}{13}$…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:53 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 Exercise 6.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-4-p7</link>
            <description>Question 7 Exercise 6.4

Solutions of Question 7 of Exercise 6.4 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.\begin{align}S&amp;=\{(i, j) ; i, j=1,2,3,4,5,6\}\\
&amp;=\left[\begin{array}{llllll}
(1,1) &amp; (1,2) &amp; (1,3) &amp; (1,4) &amp; (1,5) &amp; (1,6) \\
(2,1) &amp; (2,2) &amp; (2,3) &amp; (2,4) &amp; (2,5) &amp; (2,6) \\
(3,1) &amp; (3,2) &amp; (3,3) &amp; (3,4) &amp; (3,5) &amp; (3,6) \\
(4,1) &amp; (4,2) &amp; (…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:53 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 and 2 Exercise 6.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-5-p1</link>
            <description>Question 1 and 2 Exercise 6.5

Solutions of Question 1 and 2 of Exercise 6.5 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$A$$B$$P(A)=\dfrac{2}{5}, P(B)=\dfrac{2}{5}$$P(A \cup B)=\dfrac{1}{2}$$P(A \cap B)$\begin{align}
 P(A \cup B)&amp;=P(A)+P(B)-P(A \cap B) \\
 \Rightarrow P(A \cap B)&amp;=P(A)+P(B)-P(A \cup B)
\end{align}$P(A), P(B)$$P(A \cup B)$$$P(A \cap…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:54 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 and 4 Exercise 6.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-5-p2</link>
            <description>Question 3 and 4 Exercise 6.5

Solutions of Question 3 and 4 of Exercise 6.5 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$P(A)=0.5$$P(A \cup B)=0.6$$P(B)$$A$$B$$\mathrm{A}$$B$$A \cap B=\emptyset$\begin{align}P(A \cup B)&amp;=P(A)+P(B)\\
\Rightarrow P(B)&amp;=P(A \cup B)-P(A)\\
&amp;=0.6-.0 .5=0.1 \end{align}$30$$1$$30.$\begin{align}S&amp;=\{1,2,3, \ldots, 50\} \tex…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:55 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 and 6 Exercise 6.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-5-p3</link>
            <description>Question 5 and 6 Exercise 6.5

Solutions of Question 5 and 6 of Exercise 6.5 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\dfrac{8}{9}$$$E=\{ event\, passing\, the\, test \}$$$$E^{\prime}=\{ event\, failing\, the\, test \}$$$E$$E^{\prime}$$P(E)=\dfrac{8}{9}$\begin{align}P(E^{\prime})&amp;=1-P(E)=1-\dfrac{8}{9}=\dfrac{1}{9}\end{align}$4$$4$\begin{align}S…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:56 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 Exercise 6.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-5-p4</link>
            <description>Question 7 Exercise 6.5

Solutions of Question 7 of Exercise 6.5 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$52$$52$$26$$26$$13$$13$$13$$13$$13$$10,9,8,7,6,5,4,3$$2.$$$=\dfrac{13}{52}=\dfrac{1}{4}$$$$=\dfrac{4}{52}=\dfrac{1}{13}$$\begin{align}
P(A \cup B)&amp;=P(A)+P(B) \\
&amp; =\dfrac{1}{4}+\dfrac{1}{13}=\dfrac{17}{52} \end{align}$$=1-\dfrac{17}{52}=\dfr…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:56 +0000</pubDate>
        </item>
        <item>
            <title>Question 8 Exercise 6.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-5-p5</link>
            <description>Question 8 Exercise 6.5

Solutions of Question 8 of Exercise 6.5 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$7$$11.$\begin{align}s&amp;=(i i, j): i, j-1,2,3,4,5,6\}\\
&amp;=\left[\begin{array}{llllll}
(1.1) &amp; (1.2) &amp; (1.3) &amp; (1.4) &amp; (1.5) &amp; (1.6) \\
(2.1) &amp; (2.2) &amp; (2.3) &amp; (2.4) &amp; (2.5) &amp; (2.6) \\
(3.1) &amp; (3.2) &amp; (3.3) &amp; (3.4) &amp; (3.5) &amp; (3.6) \\
(4.1) &amp; (4…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:57 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 Exercise 6.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-5-p6</link>
            <description>Question 9 Exercise 6.5

Solutions of Question 9 of Exercise 6.5 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$2$$\dfrac{1}{7}$$\dfrac{1}{5}$\begin{align}
P(\text { Ajmal scicction })&amp;=\dfrac{1}{7} \\
\Rightarrow P(\text { Ajmal not selected })&amp;=\dfrac{6}{7} \\
P(\text { Bushra selection })&amp;=\dfrac{1}{5} \\
\Rightarrow P(\text { Bushra not selected }…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:57 +0000</pubDate>
        </item>
        <item>
            <title>Question 10 Exercise 6.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-5-p7</link>
            <description>Question 10 Exercise 6.5

Solutions of Question 10 of Exercise 6.5 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$20$$10$$5$$3$$2$$=20$$=10$$=5$$=3$$=15$$=5$$=10$$=3$$=22$$E$$a A$$B$$2$\begin{align}n(S)&amp;={ }^{30} C_2\\
&amp;=435\\
P(A)&amp;=\dfrac{^{20} C_2}{^{30} C_2}\\
&amp;=\dfrac{190}{435}=\dfrac{38}{87}\\
P(B)&amp;=\dfrac{^{22} C_2}{^{30} C_2}\\
&amp;=\dfrac{231}{43…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:58 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 Review Exercise 6</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/re-ex6-p1</link>
            <description>Question 1 Review Exercise 6

Solutions of Question 1 of Review Exercise 6 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$O, P, Q, R, S, T, U$$2520$$9040$$5140$$4880$$2520$$\{1,2,3,4,5,6,7\}$$14$$42$$28$$21$$28$$\{1,2,3,4,6,7,8\}$$3$$7$$120$$180$$144$$96$$120$$\dfrac{(n+2) !(n-2) !}{(n+1) !(n-1) !}$$(n-3)$$(\dot{n}-1)$$\dfrac{n+1}{n+2}$$\dfrac{n+2}{n-…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:59 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 Review Exercise 6</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/re-ex6-p2</link>
            <description>Question 2 Review Exercise 6

Solutions of Question 2 of Review Exercise 6 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.${ }^{2 n} C_r={ }^{2 n} C_{r+2}$$r$\begin{align}
{ }^{2 n} C_r&amp;={ }^{2 n} C_{r+2} \\
\Rightarrow \dfrac{(2 n) !}{(2 n-r) ! r !}&amp;=\dfrac{(2 n) !}{(2 n-(r+2)) !(r+2) !}\end{align}$(2 n)$\begin{align}
\Rightarrow \dfrac{1}{(2 n-r) ! r…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:00 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 &amp; 4 Review Exercise 6</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/re-ex6-p3</link>
            <description>Question 3 &amp; 4 Review Exercise 6

Solutions of Question 3 &amp; 4 of Review Exercise 6 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.${ }^{56} P_{r+6}:{ }^{54} P_{r+3}=30800: 1$$r$\begin{align}
{ }^{56} P_{r+6}:{ }^{54} P_r+3&amp;=30800: 1  \\
\Rightarrow \dfrac{\dfrac{56 !}{[56-(r+6)] !}}{\dfrac{54 !}{[54-(r+3)] !}}&amp;=\dfrac{30800}{1} \\
\Rightarrow \dfrac{56…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:00 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 &amp; 6 Review Exercise 6</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/re-ex6-p4</link>
            <description>Question 5 &amp; 6 Review Exercise 6

Solutions of Question 5 &amp; 6 of Review Exercise 6 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$$n=6$$$$(n-1) !=(6-1) !=5 !=120$$$120-24=96$$n=6$$(n-1) !=(6-1) !=5 !=120$$$(n-1) !=(5-1) !=4 !=24$$$$(n-1) !=(6-1) !=5 !=120$$$$4 ! \cdot 2 !=48$$$(5-1) !$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:01 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 &amp; 8 Review Exercise 6</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/re-ex6-p5</link>
            <description>Question 7 &amp; 8 Review Exercise 6

Solutions of Question 7 &amp; 8 of Review Exercise 6 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$P(A)=0.8, P(B)=0.5$$P(B / A)=0.4$$P(A \cap B)$\begin{align}
P(B \mid A)&amp;=\dfrac{P(A \cap B)}{P(A)} \\
\Rightarrow P(A \cap B)&amp;=P(B \mid A) \cdot P(A)\\
&amp;=0.4 \times 0.8=0.32\end{align}$P(A)=0.8, P(B)=0.5$$P(B / A)=0.4$$P(A …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:01 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 &amp; 10 Review Exercise 6</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/re-ex6-p6</link>
            <description>Question 9 &amp; 10 Review Exercise 6

Solutions of Question 9 &amp; 10 of Review Exercise 6 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$2,3,0,3,4,2,3$$1$$=100,0000$$$=\dfrac{7 !}{3 ! \cdot 2 !}=420 $$$1$$0$$7$$0$$$=\dfrac{6 !}{2 ! 3 !}=60 $$$1$$420-50=360$$n$$n$$(n-1)$$(n - 1)$$(n-1)$$(n-2) !$$2$$2 !$$n$$$(n-2) ! \cdot 2 !=2(n-2) ! $$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:03 +0000</pubDate>
        </item>
        <item>
            <title>Question 11 Review Exercise 6</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/re-ex6-p7</link>
            <description>Question 11 Review Exercise 6

Solutions of Question 11 of Review Exercise 6 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$$n(S)=4$$$\dfrac{1}{4}$$$\quad P( orange )=\dfrac{1}{4}$$$\dfrac{1}{4}$$\dfrac{1}{4}$\begin{align}P(\operatorname{Red})&amp;=\dfrac{1}{4}\\
P( Green )&amp;=\dfrac{1}{4}\end{align}$P(R \cap G)=\phi$$R$$G$\begin{align}\boldsymbol{P}( Red o…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:03 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 Exercise 7.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-1-p1</link>
            <description>Question 1 Exercise 7.1

Solutions of Question 1 of Exercise 7.1 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$2+4+6+\cdots+2 n=n(n+1)$$n=1$$$2=1(1+1)=2 $$$n=1$$n=k$$$2+4+6+\cdots+2 k=k(k+1)....(i)$$$n=k+1$$(k+1)^{t h}$$$a_{k+1}=\mathbf{2}(k+1)=2 k+2 $$$k+1$\begin{align}2+4+6+\cdots+2 k+2(k+1)&amp; =k(k+1)+2(k+1) \\
&amp; =(k+1)[k+2] \\
&amp; =(k+1)(k+1+1)\end{a…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:07 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 Exercise 7.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-1-p2</link>
            <description>Question 2 Exercise 7.1

Solutions of Question 2 of Exercise 7.1 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$1+5+9+\ldots+(4 n-3)=n(2 n-1)$$n=1$$$1=1(2.1-1)=1$$$n=1$$n=k$\begin{align}1+5+9+\ldots+(4 k-3)\\
&amp; =k(2 k-1)....(i) \\
\end{align}$n=k+1$$k+1$$$a_{k-1}=4(k+1)-3=4 k+1 $$$(k+1)^{t h}$\begin{align}1+5+9+\ldots+(4 k-3)+(4 k+1)&amp; =k(2 k-1)+4 k+1 …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:12 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 Exercise 7.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-1-p3</link>
            <description>Question 3 Exercise 7.1

Solutions of Question 3 of Exercise 7.1 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$3+6+9+\ldots+3 n=\dfrac{3 n(n+1)}{2}$$n=1$$3=\dfrac{3.1(1+1)}{2}=3$$n=1$$n=k$$$3+6+9+\ldots+3 k=\dfrac{3 k(k+1)}{2}....(i)$$$n=k+1$$(k+1)$$a_{k+1}=3(k+1)$$(k+1)^{t h}$\begin{align}3+6+9+\ldots+3 k+3(k+1) &amp; =\dfrac{3 k(k+1)}{2}+3(k+1) \\
&amp; =3…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:13 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 Exercise 7.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-1-p4</link>
            <description>Question 4 Exercise 7.1

Solutions of Question 4 of Exercise 7.1 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$3+7+11+\cdots+(4 n-1)=n(2 n+1)$$n=1$$$3=1(2+1)=3 $$$n=1$$n=k$\begin{align}3+7+11+\cdots+(4 k-1) 
&amp; =k(2 k+1)....(i) \end{align}$n=k+1$$(k+1)$$a_{k+1}=4(k+1)-1$$(k+1)^{t h}$\begin{align}
3+7+11+\cdots+(4 k-1)+[4(k+1)-1] &amp; =k(2 k+1)+4(k+1)-1 \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:13 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 Exercise 7.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-1-p5</link>
            <description>Question 5 Exercise 7.1

Solutions of Question 5 of Exercise 7.1 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$1^3+2^3+3^3+\ldots+n^3=\left[\dfrac{n(n+1)}{2}\right]^2$$n=1$$1^3=1=\left[\dfrac{1(1+1)}{2}\right]^2=1$$n=1$$n=k_1$\begin{align}1^3+2^3+3^3+\ldots+k^3&amp; =[\dfrac{k(k+1)}{2}]^2....(i)\end{aligned}
3. Now $$ the $$ term of the given series on l…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:14 +0000</pubDate>
        </item>
        <item>
            <title>Question 6 Exercise 7.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-1-p6</link>
            <description>Question 6 Exercise 7.1

Solutions of Question 6 of Exercise 7.1 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$1(1 !)+2(2 !)+3(3 !)+\ldots+n(n !)= -(n+1) !-1$$n=1$$$1(1 !)=1=(1+1) !-1=2 !-1=1 $$$n=1$$n=k$\begin{align}1(1 !)+2(2 !)+3(3 !)+\ldots+k(k !)&amp; =(k+1) !-1  \ldots . .(i)\end{align}$n=k+1$$(k+1)^{t h}$$a_{k+1}=(k+1)[(k+1) !]$$a_{k-1}$\begin{ali…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:14 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 Exercise 7.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-1-p7</link>
            <description>Question 7 Exercise 7.1

Solutions of Question 7 of Exercise 7.1 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$1.2+2.3+3.4+\ldots+n(n+1)=\dfrac{n(n+1)(n+2)}{3}$$n=1$$$1.2=2=\dfrac{1(1+1)(1+2)}{3}=2 $$$n=1$$n=k$\begin{align}1.2+2.3+3.4+\ldots+k(k+1)&amp; =\dfrac{k(k+1)(k+2)}{3}....(i)\end{align}$n=k+1$$(k-1)^{t h}$$a_{k+1}=(k+1)(k+ 2)$$(k+1)^{\text {th }}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:19 +0000</pubDate>
        </item>
        <item>
            <title>Question 8 Exercise 7.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-1-p8</link>
            <description>Question 8 Exercise 7.1

Solutions of Question 8 of Exercise 7.1 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$1+2+2^2+2^3+\ldots+2^n 1=2^n-1$$n=1$$1=2^1-1=1$$n=1$$n-k&gt;1$\begin{align}1+2+2^2+2^3+\ldots+2^{k-1} \\
&amp; =2^k-1 ....(i)\end{align}$n-k-1$$(k+1)^{t h}$$a_{k+1}=2^k$$a_{k+1}$\begin{align}1+2+2^2+2^3+\ldots+2^{k-1}-2^k &amp; =2^k-12^k \\
&amp; =2^k+2^k-…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:19 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 Exercise 7.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-1-p9</link>
            <description>Question 9 Exercise 7.1

Solutions of Question 9 of Exercise 7.1 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\dfrac{1}{3}+\dfrac{1}{9}+\dfrac{1}{27}+\ldots+\dfrac{1}{3^n}=\dfrac{1}{2}[1-\dfrac{1}{3^n}]$$n=1$$$\dfrac{1}{3}-\dfrac{1}{2}[1-\dfrac{1}{3}]-\dfrac{1}{2} \dfrac{2}{3}=\dfrac{1}{3} $$$n=1$$n=k$$$\dfrac{1}{3}+\dfrac{1}{9}+\dfrac{1}{27}+\ldots…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:21 +0000</pubDate>
        </item>
        <item>
            <title>Question 10 Exercise 7.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-1-p10</link>
            <description>Question 10 Exercise 7.1

Solutions of Question 10 of Exercise 7.1 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\left(\begin{array}{1}5 \\5 \end{array}\right)+\left(\begin{array}{l}6 \\ 5\end{array}\right)+\left(\begin{array}{l}7 \\ 5\end{array}\right)+\ldots+\left(\begin{array}{c}n+4 \\ 5\end{array}\right)=\left(\begin{array}{c}n+5 \\ 6\end{array}\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:07 +0000</pubDate>
        </item>
        <item>
            <title>Question 11 Exercise 7.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-1-p11</link>
            <description>Question 11 Exercise 7.1

Solutions of Question 11 of Exercise 7.1 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.\begin{align}
&amp; \left(\begin{array}{l}
2 \\
2
\end{array}\right)+\left(\begin{array}{l}
3 \\
2
\end{array}\right)+\left(\begin{array}{l}
4 \\
2
\end{array}\right)+\ldots+\left(\begin{array}{l}
n \\
2
\end{array}\right)=\left(\begin{array}{c…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:08 +0000</pubDate>
        </item>
        <item>
            <title>Question 12 Exercise 7.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-1-p12</link>
            <description>Question 12 Exercise 7.1

Solutions of Question 12 of Exercise 7.1 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\dfrac{5^{2 n}-1}{24}$$n=1$$$\dfrac{5^{2 n}-1}{24}=\dfrac{5^{2.1}-1}{24}=\dfrac{24}{24}=1 \in \mathbb{Z}$$$n=1$$n=k&gt;1$$$\dfrac{5^{2 k}-1}{24} \in \mathbb{Z}$$$n=k+1$\begin{align}\dfrac{5^{2(k+1)}-1}{24}&amp;=\dfrac{5^{2 k+2}-1}{24} \\
&amp; =\dfra…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:09 +0000</pubDate>
        </item>
        <item>
            <title>Question 13 Exercise 7.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-1-p13</link>
            <description>Question 13 Exercise 7.1

Solutions of Question 13 of Exercise 7.1 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$2^n&gt;n \forall n \in \mathbf{N}$$n=1$$2^n=2^1=2$$n=1$$2&gt;1$$n=1$$n=l&gt;I$$2^k&gt;k\cdots(i)$$n=k+1$\begin{align}
&amp; 2^{k+1}=2^k \cdot 2&gt;k \cdot 2 \quad \text { by (i) } \\
&amp; \Rightarrow 2^{k+1}&gt;2 k=k+k \\
&amp;\Rightarrow 2^{k+1}&gt;k+1 \text {. as } k&gt;1…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:10 +0000</pubDate>
        </item>
        <item>
            <title>Question 14 Exercise 7.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-1-p14</link>
            <description>Question 14 Exercise 7.1

Solutions of Question 14 of Exercise 7.1 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$5$$3^{2 n-1}+2^{2 n-1}$$n$$n=1$$$3^{2 n-1}+2^{2 n-1}=3^{2.1-1}+2^{2.1-1}=5 \text {. }$$$5$$5$$5$$5.$$n=1$$n=k&gt;1$$54$$3^{2 k} 1+2^{2 k} \quad 1$$$3^{2 k-1}+2^{2 k-1}=5 Q$$$Q$$n=k+1$\begin{align}
3^{2(k+1)-1}+2^{2(k+1)-1} &amp; =3^{2 k+2-1}+2^{2…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:10 +0000</pubDate>
        </item>
        <item>
            <title>Question 15 Exercise 7.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-1-p15</link>
            <description>Question 15 Exercise 7.1

Solutions of Question 15 of Exercise 7.1 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$a+b$$a^n-b^n$$n$$n$$n=2 n, \quad m \in \mathbb{Z}^{+}$$m=1$$$a^{2 n}-b^{2 m}=a^2-b^2=(a+b)(a-b)$$$\Rightarrow(a+b)$$a^2-b^2$$m=1$$n=2$$m=k$$$a^{2 k}-b^{2 k}=Q(a+b)$$$Q$$m=k+1$\begin{align}a^{2(k+1)}-b^{2(k-1)} &amp; =a^{2 k+2}-b^{2 k+2} \\
&amp; =…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:12 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 Exercise 7.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-2-p1</link>
            <description>Question 1 Exercise 7.2

Solutions of Question 1 of Exercise 7.2 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$(x^2-\dfrac{1}{y})^4$\begin{align}(x^2-\dfrac{1}{y})^4&amp;=(x^2)^4+{ }^4 C_1(x^2)^3(-\dfrac{1}{y})+ \\
&amp; { }^4 C_2(x^2)^2(-\dfrac{1}{y})^2+{ }^4 C_3(x^2)(-\dfrac{1}{y})^3 + { }^4 C_4(-\dfrac{1}{y})^4 \\
&amp; =x^8- \dfrac{4x^6}{y}+\dfrac{6x^4}{y^2}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:21 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 Exercise 7.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-2-p2</link>
            <description>Question 2 Exercise 7.2

Solutions of Question 2 of Exercise 7.2 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$4^{th}$$(2+a)^7$$\ln$$n=7$$a=2$$b=a$$$T_{r+1}=\frac{7 !}{(7-r) ! r !}(2)^{7-r } a^r $$$4^{\text {th }}$$r=3$\begin{align}
&amp; T_{3+1}=\dfrac{7 !}{(7-3) ! 3 !} 2^{7-3} a^3 \\
&amp; \Rightarrow T_4=\dfrac{7 !}{4 ! 3 !} \cdot 2^4 a^3 \\
&amp; \Rightarrow…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:23 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 Exercise 7.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-2-p3</link>
            <description>Question 3 Exercise 7.2

Solutions of Question 3 of Exercise 7.2 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$x$$(\dfrac{4 x^2}{3}-\dfrac{3}{2 x})$$n=9, \quad a=\dfrac{4 x^2}{3}$$b=-\dfrac{3}{2 x}$$T_{r+1}$$x$$T_{r+1}$\begin{align}T_{r+1}&amp;=\dfrac{9 !}{(9-r) ! r !}(\dfrac{4 x^2}{3})^{9-r}(-\dfrac{3}{2 x})^r \\
&amp; =\dfrac{9 !}{(9-r) ! r !} \cdot \dfrac…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:24 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 Exercise 7.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-2-p4</link>
            <description>Question 4 Exercise 7.2

Solutions of Question 4 of Exercise 7.2 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$x^{23}$$(x^2-x)^{20}$$n=20, \quad a=x^2$$b=-x$$T_{r, 1}$$x^{23}$\begin{align}T_{r-1}&amp;=\dfrac{20 !}{(20-r) ! r !}(x^2)^{20 r}(-x)^r \\
&amp; =\dfrac{20 !}{(20-r) ! r !}(-1)^r \cdot x^{40-2 r+r} \\
&amp; =\dfrac{20 !}{(20-r) ! r !}(-1)^r x^{40-r}\end{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:25 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 Exercise 7.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-2-p5</link>
            <description>Question 5 Exercise 7.2

Solutions of Question 5 of Exercise 7.2 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$(\dfrac{a}{x}+b x)^8$$a=\dfrac{a}{x}$$b=b x$$n=8$$n-8$$8+1=9$$$(\dfrac{8+2}{2})^{t h}=5^{t h}$$T_{r+1}$$$T_{r+1}=\dfrac{8 !}{(8-r) ! r !}(\dfrac{a}{x})^{8-r}(b x)^r$$$T_5$$r=4$\begin{align}T_5&amp;=\dfrac{8 !}{(8-4) ! 4 !}(\dfrac{a}{x})^{8-4}(b …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:25 +0000</pubDate>
        </item>
        <item>
            <title>Question 6 Exercise 7.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-2-p6</link>
            <description>Question 6 Exercise 7.2

Solutions of Question 6 of Exercise 7.2 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$(2 \sqrt{x}-\dfrac{3}{x \sqrt{x}})^{23}$$a=2 \sqrt{x}$$b=-\dfrac{3}{x \sqrt{x}}$$n=23$$x$\begin{align}
T_{r+1}&amp;=\dfrac{23 !}{(23-r) ! r !}(2 \sqrt{x})^{23-r}(-\dfrac{3}{x \sqrt{x}})^r \\
&amp; =\dfrac{23 !}{(23-r) ! r !} \cdot 2^{23-r} \cdot(-3)…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:27 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 Exercise 7.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-2-p7</link>
            <description>Question 7 Exercise 7.2

Solutions of Question 7 of Exercise 7.2 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$(2+\sqrt{3})^5+(2-\sqrt{3})^5$\begin{align}(2+\sqrt{3})^5+(2 \cdot \sqrt{3})^5&amp; =[(2)^5+{ }^5 C_1 \cdot 2^4 \cdot \sqrt{3}+{ }^5 C_2 \cdot 2^3 \cdot(\sqrt{3})^2 \\
&amp; +^5 C_3 \cdot 2^2 \cdot(\sqrt{3})^4+{ }^5 C_4 \cdot 2 \cdot(\sqrt{3})^4 \\
…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:27 +0000</pubDate>
        </item>
        <item>
            <title>Question 8 Exercise 7.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-2-p8</link>
            <description>Question 8 Exercise 7.2

Solutions of Question 8 of Exercise 7.2 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$(3-2 x)^{10}$$x=\frac{3}{4}$$\left(3-2,1^{10}=3^{10}\left(1-\frac{3 x}{2}\right)^{10}\right.$$\left(1-\frac{3 x}{2}\right)^{10}$$p+1$$: 3-\mathbf{2}_1 1^{10}$$T_{5} !=\left(\begin{array}{c}10 \\ 5\end{array}\right) 3^{10} 5-2 \gamma^{15}$$x=…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:28 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 Exercise 7.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-2-p9</link>
            <description>Question 9 Exercise 7.2

Solutions of Question 9 of Exercise 7.2 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$(x-y)=&quot;$$x=12$$y-4$$x=12$$$
\begin{aligned}
&amp; \left(x \quad y=20(12-y)^{20}\right. \\
&amp; =12^{2 n}\left(\begin{array}{ll}
1 &amp; \frac{y}{12}
\end{array}\right)^{31}
\end{aligned}
$$$\frac{(n+1) \cdot x}{1+|x|}$$\left(\frac{1}{12}\right)^2 \cdot…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:28 +0000</pubDate>
        </item>
        <item>
            <title>Question 10 Exercise 7.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-2-p10</link>
            <description>Question 10 Exercise 7.2

Solutions of Question 10 of Exercise 7.2 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$n=2 ;$$s=2^{n-1}$$$
\left.(1+x)^n=\left(\begin{array}{l}
n \\
\vdots
\end{array}\right)+\left(\begin{array}{l}
m \\
1
\end{array}\right) x+\left(\begin{array}{l}
n \\
2
\end{array}\right) x^2-\ldots+i_n^*\right) x^n \cdot
$$$x=1$$(1 \div 1…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:22 +0000</pubDate>
        </item>
        <item>
            <title>Question 11 Exercise 7.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-2-p11</link>
            <description>Question 11 Exercise 7.2

Solutions of Question 11 of Exercise 7.2 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$(1+x)^n$$\left(\begin{array}{l}n \\ r\end{array}\right)=\mathrm{C}_r$$\mathrm{C}_1+2 \mathrm{C}_2 x+3 \mathrm{C}_3 x^2+\ldots \ldots . .+\mathrm{nC}_{\mathrm{n}} x^{\mathrm{n}-1}=\mathrm{n}(1+x)^{\mathrm{n}-1}$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:22 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 Exercise 7.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-3-p1</link>
            <description>Question 1 Exercise 7.3

Solutions of Question 1 of Exercise 7.3 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\frac{1}{2}$$$
\begin{aligned}
&amp; (1-x)^{\frac{1}{2}}=1+\frac{1}{2} x+ \\
&amp; \frac{\frac{1}{2}\left(-\frac{1}{2}-1\right)}{2 !}(-x)^2
\end{aligned}
$$$$
\begin{aligned}
&amp; +\frac{-\frac{1}{2}\left(-\frac{1}{2}-1\right)\left(-\frac{1}{2}-2\right…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:29 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 Exercise 7.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-3-p2</link>
            <description>Question 2 Exercise 7.3

Solutions of Question 2 of Exercise 7.3 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\sqrt{26}$$$
\begin{aligned}
&amp; \sqrt{26}=\sqrt{25+1} \\
&amp; =\sqrt{25} \sqrt{1+\frac{1}{25}}=5\left[1+\frac{1}{25}\right]^{\frac{1}{2}}
\end{aligned}
$$$$
\begin{aligned}
&amp; \sqrt{26}=5\left[1+\frac{1}{25}\right]^{\frac{1}{2}} \\
&amp; =5\left[1+\f…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:32 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 Exercise 7.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-3-p3</link>
            <description>Question 3 Exercise 7.3

Solutions of Question 3 of Exercise 7.3 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\sqrt{\frac{1-x}{1+x}}$$x^3$$\sqrt{\frac{1-x}{1+x}}$$$
=(1-x)^{\frac{1}{2}}(1+x)^{-\frac{1}{2}} \text {. }
$$$$
\begin{aligned}
&amp; (1-x)^{\frac{1}{2}}(1+x)^{\frac{1}{2}} \\
&amp; =\left[1-\frac{x}{2}+\frac{\frac{1}{2}\left(\frac{1}{2}-1\right)}{2…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:33 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 Exercise 7.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-3-p4</link>
            <description>Question 4 Exercise 7.3

Solutions of Question 4 of Exercise 7.3 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$x$$x^2$$x$$$
\sqrt{\frac{1-3 x}{1+4 x}}=1-\frac{7 x}{2}
$$$$
\sqrt{\frac{1-3 x}{1-4 x}}=(1-3 x)^{\frac{1}{2}}(1+4 x)^{-\frac{1}{2}}
$$$x^2$$x$$$
\begin{aligned}
&amp; =\left(1-\frac{3 x}{2}\right) \times\left(1-\frac{4 x}{2}\right) \\
&amp; =\left(1…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:34 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 and 6 Exercise 7.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-3-p5</link>
            <description>Question 5 and 6 Exercise 7.3

Solutions of Question 5 and 6 of Exercise 7.3 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$x$$x^2$$x$$$
\frac{(8+3 x)^{\frac{2}{3}}}{(2+3 x) \sqrt{4-5 x}}=1-\frac{5 x}{8}
$$$$
\frac{\sqrt[4]{3}-3 x j^{\frac{2}{3}}}{2 \cdot 3 x+4-5 x}
$$$$
\begin{aligned}
&amp; =\frac{8^{\frac{2}{3}}\left(1+\frac{3 x}{8}\right)^{\frac{2}{3}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:34 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 and 8 Exercise 7.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-3-p6</link>
            <description>Question 7 and 8 Exercise 7.3

Solutions of Question 7 and 8 of Exercise 7.3 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$x^4$$(1-x)^{\frac{1}{4}}+(1-x)^{\frac{1}{4}}=a-b x^2$$a$$b$$$
\begin{aligned}
&amp; (1+x)^{\frac{1}{4}}+(1-x)^{\frac{1}{4}} \\
&amp; =\left[1+\frac{x}{4}+\frac{\frac{1}{4}\left(\frac{1}{4}-1\right)}{2 !} x^2+\right. \\
&amp; \left.\frac{\fra…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:35 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 Exercise 7.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-3-p7</link>
            <description>Question 9 Exercise 7.3

Solutions of Question 9 of Exercise 7.3 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$x^{\prime \prime}$$\left(\frac{1+x}{1-x}\right)^2$$$
\begin{aligned}
&amp; \left(\frac{1+x}{1-x}\right)^2=(1+x)^2(1-x)^{-2} \\
&amp; =\left(x^2+2 x+1\right)(1-x)^2
\end{aligned}
$$$$
\begin{aligned}
&amp; =\left(x^2+2 x+1\right)[1+2 x+ \\
&amp; \frac{-2(-2-…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:36 +0000</pubDate>
        </item>
        <item>
            <title>Question 10 Exercise 7.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-3-p8</link>
            <description>Question 10 Exercise 7.3

Solutions of Question 10 of Exercise 7.3 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$1-\frac{1}{2^2}+\frac{1.3}{2 !} \cdot \frac{1}{2^4}+\ldots$$(1+x)^n$$$
\begin{aligned}
&amp; 1+n x+\frac{n(n-1)}{2 !} x^2 \\
&amp; +\frac{n(n-1(n-2))}{3 !} x^3+\ldots
\end{aligned}
$$$n x=-\frac{1}{4}$$\frac{n(n-1)}{2 !} x^2=\frac{1.3}{2 !} \cdot …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:37 +0000</pubDate>
        </item>
        <item>
            <title>Question 11 Exercise 7.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-3-p9</link>
            <description>Question 11 Exercise 7.3

Solutions of Question 11 of Exercise 7.3 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$y=\frac{1}{2^2}+\frac{1.3}{2 !} \cdot \frac{1}{2^4}+\frac{1 \cdot 3 \cdot 5}{3 !} \cdot \frac{1}{2^6}+\ldots$$y^2+2 y-1=0$$y=\frac{1}{2^2}+\frac{1.3}{2 !} \cdot \frac{1}{2^4}+\frac{1.3 \cdot 5}{3 !} \cdot \frac{1}{2^6}+\ldots$$$
S=y+1=1+\f…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:38 +0000</pubDate>
        </item>
        <item>
            <title>Question 12 Exercise 7.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-3-p10</link>
            <description>Question 12 Exercise 7.3

Solutions of Question 12 of Exercise 7.3 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$2 y=\frac{1}{2^2}+\frac{1.3}{2 !} \cdot \frac{1}{2^4}+\frac{1.3 \cdot 5}{3 !} \cdot \frac{1}{2^6}+\ldots$$4 y^2+4 y-1=0$$$
2 y=\frac{1}{2^2}+\frac{1.3}{2 !} \cdot \frac{1}{2^4}-\frac{1.3 \cdot 5}{3 !} \cdot \frac{1}{2^6}+\ldots
$$$S=2 y+1=…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:30 +0000</pubDate>
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        <item>
            <title>Question 13 Exercise 7.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-3-p11</link>
            <description>Question 13 Exercise 7.3

Solutions of Question 13 of Exercise 7.3 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$x$$x^3$$x$$n^{\text {th }}$$1+x$$\frac{2 n+(n+1) x}{2 n+(n-1) x}$$$
\begin{aligned}
&amp; (1+x)^{\frac{1}{n}}=\frac{2 n+(n+1) x}{2 n+(n-1) x} \\
&amp; \frac{2 n+(n+1) x}{2 n+(n-1) x} \\
&amp; =1+\frac{1}{n} x+\frac{\frac{1}{n}\left(\frac{1}{n}-1\right…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:31 +0000</pubDate>
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        <item>
            <title>Question 14 Exercise 7.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-3-p12</link>
            <description>Question 14 Exercise 7.3

Solutions of Question 14 of Exercise 7.3 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$x$$p x^p-q x^q=(p-q) x^{p+q}$$x$$x=1+h$$h \longrightarrow 0$$$
p x^p-q x^q=p(1+h)^p-q(1+h)^q
$$$$
\begin{aligned}
&amp; p x^p-q x^q \\
&amp; =p(1+p h+\text { higher powers h) } \\
&amp; -q(1+q h+\text { higher powcrs } h) \\
&amp; \Rightarrow p x^p-q x^q=…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:31 +0000</pubDate>
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        <item>
            <title>Question 1 Review Exercise 7</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/re-ex7-p1</link>
            <description>Question 1 Review Exercise 7

Solutions of Question 1 of Review Exercise 7 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.
Chose the correct option.$O, P, Q, R, S, T, U$$2520$$9040$$5140$$4880$$2520$$\{1,2,3,4,5,6,7\}$$14$$42$$28$$21$$28$$\{1,2,3,4,6,7,8\}$$3$$7$$120$$180$$144$$96$$120$$\dfrac{(n+2) !(n-2) !}{(n+1) !(n-1) !}$$(n-3)$$(\dot{n}-1)$$\dfrac…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:38 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 Review Exercise 7</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/re-ex7-p2</link>
            <description>Question 2 Review Exercise 7

Solutions of Question 2 of Review Exercise 7 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\left(2 x^3+3 y\right)^8$$a=2 x^3$$b=3 y$$n=8$$n=8$$\frac{8+2}{2}=5$$$
\begin{aligned}
&amp; T_5=\frac{8 !}{(8-4) ! 4 !}\left(2 x^3\right)^{8-4}(3 y)^4 \\
&amp; T_5=70.2^4 \cdot 3^4 \cdot x^{12} \cdot y^4 \\
&amp; =90720 x^{12} y^4
\end{aligne…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:40 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 &amp; 4 Review Exercise 7</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/re-ex7-p3</link>
            <description>Question 3 &amp; 4 Review Exercise 7

Solutions of Question 3 &amp; 4 of Review Exercise 7 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$(2 x-4 y)^7$$n=7, a=2 x$$b=-4 y$$$
\begin{aligned}
&amp; T_{3+1}=\frac{7 !}{(7-3) ! 3 !}(2 x)^{7 \cdot 3}(-4 y)^3 \\
&amp; =\frac{7 !}{(7-3) ! 3 !} \cdot\left(2^4\right) \cdot(-4)^3 \cdot x^4 y^3 \\
&amp; \Rightarrow T_4=-35840 x^4 y^3…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:40 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 &amp; 6 Review Exercise 7</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/re-ex7-p4</link>
            <description>Question 5 &amp; 6 Review Exercise 7

Solutions of Question 5 &amp; 6 of Review Exercise 7 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\left(\frac{2}{x^2}+\frac{x^2}{2}\right)^{10}$$n=10, a^{\prime}=\frac{2}{x^2}$$b=\frac{x^2}{2}$$T_{r+1}$$x$$$
\begin{aligned}
&amp; T_{r+1}=\frac{10 !}{(10-r) ! r !}\left(\frac{2}{x^2}\right)^{10 r}\left(\frac{x^2}{2}\right)^r …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:41 +0000</pubDate>
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        <item>
            <title>Question 7 &amp; 8 Review Exercise 7</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/re-ex7-p5</link>
            <description>Question 7 &amp; 8 Review Exercise 7

Solutions of Question 7 &amp; 8 of Review Exercise 7 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$7^n-3^n$$n=1$$7^k-3^k=7-4=4$$n=1$$n=k&gt;1$$7^n-3^n=4 Q$$Q$$n=k+1$$$
\begin{aligned}
&amp; 7^{k+1}-3^{k+1}=7.7^k-3.3^k \\
&amp; =(4+3) \cdot 7^k-3.3^k \\
&amp; =4.7^k+3.7^k-3.3^k
\end{aligned}
$$$$
\begin{aligned}
&amp; =4.7^k+3\left[7^k-3^k\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:41 +0000</pubDate>
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        <item>
            <title>Question 9 and 10 Review Exercise 7</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/re-ex7-p6</link>
            <description>Question 9 and 10 Review Exercise 7

Solutions of Question 9 and 10 of Review Exercise 7 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:43 +0000</pubDate>
        </item>
        <item>
            <title>Question 11 Review Exercise 7</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/re-ex7-p7</link>
            <description>Question 11 Review Exercise 7

Solutions of Question 11 of Review Exercise 7 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:43 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 10.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/ex10-1-p1</link>
            <description>Question 1, Exercise 10.1

Solutions of Question 1 of Exercise 10.1 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan. There are four parts in Question 1.$\sin {{37}^{\circ }}\cos {{22}^{\circ }}+\cos {{37}^{\circ }}\sin {{22}^{\circ }}$\begin{align} \sin (\alpha +\beta )=\sin \alpha \cos \beta +\cos \alpha \sin \beta, \end{align}\begin{a…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:35 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Exercise 10.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/ex10-1-p2</link>
            <description>Question 2, Exercise 10.1

Solutions of Question 2 of Exercise 10.1 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\sin \dfrac{\pi }{12}$$\dfrac{\pi }{12}$$\dfrac{\pi }{3}-\dfrac{\pi }{4}$\begin{align}\sin (\alpha -\beta )=\sin \alpha \cos \beta -\cos \alpha \sin.\end{align}\begin{align} \Rightarrow \quad \sin \left( \frac{\pi }{3}-\f…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:37 +0000</pubDate>
        </item>
        <item>
            <title>Question 3, Exercise 10.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/ex10-1-p3</link>
            <description>Question 3, Exercise 10.1

Solutions of Question 3 of Exercise 10.1 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\sin u=\dfrac{3}{5}$$\sin v=\dfrac{4}{5}$$u$$v$$0$$\dfrac{\pi }{2}$$\cos \left( u+v \right)$$\sin u=\dfrac{3}{5},$$0\le u\le \dfrac{\pi }{2}.$$\sin v=\dfrac{4}{5},$$0\le v\le \dfrac{\pi }{2}.$$\cos u=\pm \sqrt{1-{{\sin }^…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:40 +0000</pubDate>
        </item>
        <item>
            <title>Question, Exercise 10.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/ex10-1-p4</link>
            <description>Question, Exercise 10.1

Solutions of Question 4 of Exercise 10.1 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\sin \alpha =-\dfrac{4}{5}$$\cos \beta =-\dfrac{12}{13}$$\alpha $$\beta $$\sin \left( \alpha -\beta  \right)$$\sin \alpha=-\dfrac{4}{5}$$\alpha$$\sin \beta=-\dfrac{12}{13}$$\beta$$$\cos \alpha=\pm \sqrt{1-\sin^2\alpha}.$$$\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:39 +0000</pubDate>
        </item>
        <item>
            <title>Question 5, Exercise 10.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/ex10-1-p5</link>
            <description>Question 5, Exercise 10.1

Solutions of Question 5 of Exercise 10.1 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\tan \alpha =\dfrac{3}{4}$$\sec \beta =\dfrac{13}{5}$$\alpha$$\beta$$\sin \left( \alpha +\beta  \right)$$\tan\alpha =\dfrac{3}{4}$$\tan\alpha$$\alpha$\begin{align}{{\sec}^{2}}\alpha &amp;=1+{{\tan}^{2}}\alpha\\
\Rightarrow \q…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:42 +0000</pubDate>
        </item>
        <item>
            <title>Question 6, Exercise 10.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/ex10-1-p6</link>
            <description>Question 6, Exercise 10.1

Solutions of Question 1 of Exercise 10.1 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\cos \alpha =2{{\cos }^{2}}\dfrac{\alpha }{2}-1=1-2{{\sin }^{2}}\dfrac{\alpha }{2}$\begin{align}\cos \alpha &amp;=\cos 2\dfrac{\alpha }{2}\\
&amp;={{\cos }^{2}}\dfrac{\alpha }{2}-{{\sin }^{2}}\dfrac{\alpha }{2}\\ 
&amp;={{\cos }^{2}}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:42 +0000</pubDate>
        </item>
        <item>
            <title>Question 7, Exercise 10.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/ex10-1-p7</link>
            <description>Question 7, Exercise 10.1

Solutions of Question 1 of Exercise 10.1 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\cot \left( \alpha +\beta  \right)=\dfrac{\cot \alpha \cot \beta -1}{\cot \alpha +\cot \beta }$\begin{align}L.H.S.&amp;=\cot (\alpha +\beta )\\
&amp;=\dfrac{1}{\tan (\alpha +\beta )}\\
&amp;=\dfrac{1}{\,\dfrac{\tan \alpha +\tan \beta…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:44 +0000</pubDate>
        </item>
        <item>
            <title>Question 8, Exercise 10.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/ex10-1-p8</link>
            <description>Question 8, Exercise 10.1

Solutions of Question 8 of Exercise 10.1 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\tan \left( \dfrac{\pi }{4}+\theta  \right)=\dfrac{\cos \theta +\sin \theta }{\cos \theta -\sin \theta }$\begin{align}L.H.S.&amp;=\tan \left( \dfrac{\pi }{4}+\theta  \right)\\ 
&amp;=\dfrac{\sin \left( \dfrac{\pi }{4}+\theta  \ri…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:44 +0000</pubDate>
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        <item>
            <title>Question 9 and 10, Exercise 10.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/ex10-1-p9</link>
            <description>Question 9 and 10, Exercise 10.1

Solutions of Question 9 and 10 of Exercise 10.1 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\dfrac{\sin \theta }{\sec 4\theta }+\dfrac{\cos \theta }{\cos ec4\theta }=\sin 5\theta $\begin{align}L.H.S.&amp;=\dfrac{\sin \theta }{\sec 4\theta }+\dfrac{\cos \theta }{\cos ec4\theta }\\
&amp;=\dfrac{\sin \theta }…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:47 +0000</pubDate>
        </item>
        <item>
            <title>Question11 and 12, Exercise 10.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/ex10-1-p10</link>
            <description>Question11 and 12, Exercise 10.1

Solutions of Question 11 and 12 of Exercise 10.1 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\alpha$$\beta$$\gamma$$ABC$$\cot \dfrac{\alpha }{2}+\cot \dfrac{\beta }{2}+\cot \dfrac{\gamma }{2}=\cot \dfrac{\alpha }{2}\cot \dfrac{\beta }{2}\cot \dfrac{\gamma }{2}$$\alpha$$\beta$$\gamma$\begin{align}&amp;\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:35 +0000</pubDate>
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        <item>
            <title>Question 13, Exercise 10.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/ex10-1-p11</link>
            <description>Question 13, Exercise 10.1

Solutions of Question 13 of Exercise 10.1 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$r\,\,\sin \left( \theta +\phi  \right)$$\theta$$\phi$$4\sin \theta +3\cos \theta .$$4\sin \theta +3\cos \theta$$r\sin(\theta + \varphi)$$$4\sin \theta +3\cos \theta=r\cos\varphi\sin\theta+r\sin\varphi\cos\theta --- (1)$…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:37 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 10.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/ex10-2-p1</link>
            <description>Question 1, Exercise 10.2

Solutions of Question 1 of Exercise 10.2 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan. There are four parts in Question 1.$\sin 2\theta ,\,\,\cos 2\theta$$\tan 2\theta$$\tan \theta =-\dfrac{1}{5}$$\theta$$\sin \theta =\dfrac{1}{\sqrt{26}}$$\cos \theta =\dfrac{-5}{\sqrt{26}}$\begin{align}\sin 2\theta &amp;=2\sin…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:47 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Exercise 10.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/ex10-2-p2</link>
            <description>Question 2, Exercise 10.2

Solutions of Question 2 of Exercise 10.2 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\sin \theta =\dfrac{5}{13}$$\theta $$\sin 2\theta $$\sin \theta =\dfrac{5}{13}$$$\cos \theta =\pm \sqrt{1-{{\sin }^{2}}\theta }.$$$\theta$$\cos$\begin{align}\cos\theta &amp;=-\sqrt{1-{{\sin }^{2}}\theta }\\
&amp;=-\sqrt{1-\left(\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:52 +0000</pubDate>
        </item>
        <item>
            <title>Question 3, Exercise 10.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/ex10-2-p3</link>
            <description>Question 3, Exercise 10.2

Solutions of Question 3 of Exercise 10.2 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\sin \theta =\dfrac{4}{5}$$\theta$$\sin2\theta$$\sin \theta =\dfrac{4}{5}$$\theta$$\cos \theta =-\dfrac{3}{5}$\begin{align}\sin 2\theta &amp;=2\sin \theta \cos \theta \\
&amp;=2\left( \dfrac{4}{5} \right)\left( -\dfrac{3}{5} \rig…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:52 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 and 5, Exercise 10.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/ex10-2-p4</link>
            <description>Question 4 and 5, Exercise 10.2

Solutions of Question 4 and 5 of Exercise 10.2 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\cos \theta =-\dfrac{3}{7}$$\theta $$\sin \dfrac{\theta }{2}$$\cos \theta =-\dfrac{3}{7}$$\theta$\begin{align}&amp;\pi &lt; \theta &lt; \dfrac{3\pi}{2} \\
\implies &amp;\frac{\pi}{2} &lt; \frac{\theta}{2} &lt; \dfrac{3\pi}{4}\end…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:55 +0000</pubDate>
        </item>
        <item>
            <title>Question 6, Exercise 10.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/ex10-2-p5</link>
            <description>Question 6, Exercise 10.2

Solutions of Question 6 of Exercise 10.2 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\cos {{15}^{\circ }}$${{15}^{\circ }}=\dfrac{{{30}^{\circ }}}{2}$$\dfrac{\theta }{2}=\dfrac{{{30}^{\circ }}}{2}$$\cos {{15}^{\circ }}$\begin{align}\cos {{15}^{\circ }}&amp;=\cos \dfrac{{{30}^{\circ }}}{2}=\sqrt{\dfrac{1+\cos …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:55 +0000</pubDate>
        </item>
        <item>
            <title>Question 7, Exercise 10.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/ex10-2-p6</link>
            <description>Question 7, Exercise 10.2

Solutions of Question 7 of Exercise 10.2 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.${{\cos }^{4}}\theta -{{\sin }^{4}}\theta =\dfrac{1}{\sec 2\theta }$\begin{align}L.H.S&amp;={{\cos }^{4}}\theta -{{\sin }^{4}}\theta \\ 
&amp;=\left( {{\cos }^{2}}\theta -{{\sin }^{2}}\theta  \right)\left( {{\cos }^{2}}\theta +{{\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:46:00 +0000</pubDate>
        </item>
        <item>
            <title>Question 8 and 9, Exercise 10.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/ex10-2-p7</link>
            <description>Question 8 and 9, Exercise 10.2

Solutions of Question 8 and 9 of Exercise 10.2 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.${{\cos }^{4}}\theta $\begin{align}{{\cos}^{4}}\theta &amp;={{\left( {{\cos }^{2}}\theta  \right)}^{2}}\\
&amp;={{\left( \dfrac{1+\cos 2\theta }{2} \right)}^{2}}\\ 
&amp;=\dfrac{1+2\cos 2\theta +{{\cos }^{2}}2\theta }{4}\\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:46:00 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 10.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/ex10-3-p1</link>
            <description>Question 1, Exercise 10.3

Solutions of Question 1 of Exercise 10.3 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan. There are four parts in Question 1.$2\sin 6x\sin x$$$-2\sin \alpha \sin \beta =\cos (\alpha +\beta )-\cos (\alpha -\beta ).$$$\alpha =6x$$\beta =x$\begin{align}-\,2\sin 6x\sin x&amp;=\cos (6x+x)-\cos (6x-x)\\
&amp;=\cos 7x-\cos x…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:46:02 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Exercise 10.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/ex10-3-p2</link>
            <description>Question 2, Exercise 10.3

Solutions of Question 2 of Exercise 10.3 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$$\sin {{37}^{\circ }}+\sin {{43}^{\circ }}.$$$$\sin \alpha +\sin \beta =2\sin \left( \dfrac{\alpha +\beta }{2} \right)\cos \left( \dfrac{\alpha -\beta }{2} \right).$$$\alpha ={{37}^{\circ }}$$\beta ={{43}^{\circ }}$\begin…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:46:02 +0000</pubDate>
        </item>
        <item>
            <title>Question 3, Exercise 10.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/ex10-3-p3</link>
            <description>Question 3, Exercise 10.3

Solutions of Question 3 of Exercise 10.3 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$$\dfrac{\cos {{75}^{\circ }}+\cos {{15}^{\circ }}}{\sin {{75}^{\circ }}-\sin {{15}^{\circ }}}=\sqrt{3}.$$$$\cos \alpha +\cos \beta =2\cos \left( \dfrac{\alpha +\beta }{2} \right)\cos \left( \dfrac{\alpha -\beta }{2} \righ…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:46:04 +0000</pubDate>
        </item>
        <item>
            <title>Question 5, Exercise 10.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/ex10-3-p4</link>
            <description>Question 5, Exercise 10.3

Solutions of Question 5 of Exercise 10.3 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$$\cos {{20}^{\circ }}\cos {{40}^{\circ }}\cos {{60}^{\circ }}\cos {{80}^{\circ }}=\dfrac{1}{16}.$$$2\cos \alpha \cos \beta =\cos \left( \alpha +\beta  \right)+\cos \left( \alpha -\beta  \right)$\begin{align}L.H.S.&amp;=\cos {…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:46:05 +0000</pubDate>
        </item>
        <item>
            <title>Question 5, Exercise 10.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/ex10-3-p5</link>
            <description>Question 5, Exercise 10.3

Solutions of Question 5 of Exercise 10.3 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\cos {{20}^{\circ }}\cos {{40}^{\circ }}\cos {{60}^{\circ }}\cos {{80}^{\circ }}=\dfrac{1}{16}$$2\cos \alpha \cos \beta =\cos \left( \alpha +\beta  \right)+\cos \left( \alpha -\beta  \right)$\begin{align}L.H.S.&amp;=\cos {{20…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:46:06 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Review Exercise 10</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/re-ex10-p1</link>
            <description>Question 1, Review Exercise 10

Solutions of Question 1 of Review Exercise 10 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\cos {{50}^{\circ }}5{0}&#039;\cos {{9}^{\circ }}1{0}&#039;-\sin {{50}^{\circ }}5{0}&#039;\sin {{9}^{\circ }}1{0}&#039;=$$0$$\dfrac{1}{2}$$1$$\dfrac{\sqrt{3}}{2}$$\dfrac{1}{2}$$\tan {{15}^{\circ }}=2-\sqrt{3}$${{\cot }^{2}}{{75}^{\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 16 Mar 2024 13:12:33 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 and 3, Review Exercise 10</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/re-ex10-p2</link>
            <description>Question 2 and 3, Review Exercise 10

Solutions of Question 2 and 3 of Review Exercise 10 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\dfrac{2\sin \theta \sin 2\theta }{\cos \theta +\cos 3\theta }=\tan 2\theta \tan \theta $\begin{align}L.H.S.&amp;=\dfrac{2\sin \theta \sin 2\theta }{\cos \theta +\cos 3\theta }\\
&amp;=\dfrac{2\sin \theta \s…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:46:19 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 &amp; 5, Review Exercise 10</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/re-ex10-p3</link>
            <description>Question 4 &amp; 5, Review Exercise 10

Solutions of Question 4 &amp; 5 of Review Exercise 10 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.${{\sin }^{2}}\dfrac{\theta }{2}=\dfrac{\sin \theta \tan \dfrac{\theta }{2}}{2}$\begin{align}R.H.S.&amp;=\dfrac{\sin \theta \tan \dfrac{\theta }{2}}{2}\\
&amp;=\dfrac{\sin \theta \sin \dfrac{\theta }{2}}{2\cos \d…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:46:19 +0000</pubDate>
        </item>
        <item>
            <title>Question 6 &amp; 7, Review Exercise 10</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/re-ex10-p4</link>
            <description>Question 6 &amp; 7, Review Exercise 10

Solutions of Question 6 &amp; 7 of Review Exercise 10 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\cos 4\theta =1-8{{\sin }^{2}}\theta {{\cos }^{2}}\theta $\begin{align}L.H.S&amp;=\cos 4\theta \\
&amp;=\cos 2\left( 2\theta  \right)\\
&amp;=1-2\sin^2 2\theta \\
&amp;=1-2{{\left( 2\sin\theta \cos \theta  \right)}^{2}}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:46:28 +0000</pubDate>
        </item>
        <item>
            <title>Question 8 &amp; 9, Review Exercise 10</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/re-ex10-p5</link>
            <description>Question 8 &amp; 9, Review Exercise 10

Solutions of Question 8 &amp; 9 of Review Exercise 10 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\sin \left( \dfrac{\pi }{4}-\theta  \right)\sin \left( \dfrac{\pi }{4}+\theta  \right)=\dfrac{1}{2}\cos 2\theta $$2\sin \alpha \sin \beta =\cos \left( \alpha -\beta  \right)-\cos \left( \alpha +\beta  \r…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:46:32 +0000</pubDate>
        </item>
        <item>
            <title>Exercise 1.1 (Solutions)</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-1</link>
            <description>Exercise 1.1 (Solutions)

The solutions of the Exercise 1.1 of book “Model Textbook of Mathematics for Class XI” published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan are given on this page. This exercise consists of the question related to sum, product and division of the complex numbers.${{i}^{31}}$${{\left( -i \right)}^{6}}$${{\left( -1 \right)}^{\frac{-13}{2}}}$$\dfrac{2}{(-1)^{\frac{3}{2}}}$$i^{23}+i^{58}+i^{21}$$x+iy$$(3+2i)+(2+4i)$$(4+3i)-(2+5i)$$(4+7i…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 27 Oct 2025 18:50:29 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 1.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-1-p1</link>
            <description>Question 1, Exercise 1.1

Solutions of Question 1 of Exercise 1.1 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 1(i)
${{i}^{31}}$\begin{align}{{i}^{31}}&amp;=i\cdot{{i}^{30}}\\
&amp;=i\cdot{{\left( {{i}^{2}} \right)}^{15}}\\
&amp;=i\cdot{{\left( -1 \right)}^{15}} \quad \because i^2=-1\\
&amp;=i\cdot(-1)\\
&amp;=-i.\end{align}${{\left( -i \right)}^{6}}$\begin{align}
{{\left…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Jul 2024 09:40:00 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Exercise 1.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-1-p2</link>
            <description>Question 2, Exercise 1.1

Solutions of Question 2 of Exercise 1.1 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 2(i)
$x+iy$$(3+2i)+(2+4i)$\begin{align}&amp;(3+i2)+(2+i4)\\
=&amp;(3+2)+(i2+i4)\\
=&amp;5+i6\end{align}$x+iy$$(4+3i)-(2+5i)$\begin{align}&amp;(4+3i)-(2+5i)\\
=&amp;(4-2)+(3i-5i)\\
=&amp;2-2i\end{align}$x+iy$$(4+7i)+(4-7i)$\begin{align}
&amp;(4+7i)+(4-7i)\\
=&amp;(4+4)+(7i-7i…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Jul 2024 12:10:43 +0000</pubDate>
        </item>
        <item>
            <title>Question 3, Exercise 1.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-1-p3</link>
            <description>Question 3, Exercise 1.1

Solutions of Question 3 of Exercise 1.1 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 3(i)
$\dfrac{(2+i)(3-2i)}{1+i}$\begin{align}&amp;\dfrac{(2+i)(3-2i)}{1+i}\\
=&amp;\dfrac{6-2i^2+3i-4i}{1+i}\\
=&amp;\dfrac{8-i}{1+i}\\
=&amp;\dfrac{8-i}{1+i}\times \dfrac{1-i}{1-i}\\
=&amp;\dfrac{8+i^2-8i-i}{1^2-i^2}\\
=&amp;\dfrac{7-9i}{2}\\
=&amp;\dfrac{7}{2}-\dfrac{9}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Jul 2024 12:24:16 +0000</pubDate>
        </item>
        <item>
            <title>Question 4, Exercise 1.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-1-p4</link>
            <description>Question 4, Exercise 1.1

Solutions of Question 4 of Exercise 1.1 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 4(i)
$x$$y$$(2+3i)x+(1+3i)y+2=0$\begin{align}&amp;(2+3i)x+(1+3i)y+2=0\\
\implies &amp;(2x+y+2)+(3x+3y)i=0.\end{align}\begin{align}
2x+y+2&amp;=0 \quad \cdots(1)\\
3x+3y&amp;=0\quad \cdots (2)
\end{align}\begin{align}
&amp;3x=-3y \\
x=-y \quad ... (3) \end{align}$…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Jul 2024 12:39:29 +0000</pubDate>
        </item>
        <item>
            <title>Question 5, Exercise 1.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-1-p5</link>
            <description>Question 5, Exercise 1.1

Solutions of Question 5 of Exercise 1.1 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 5
$z$$4z-3\bar{z}=\dfrac{1-18i}{2-i}$$z=x+iy$$\bar{z}=x-iy$\begin{align}&amp;4z-3\bar{z}=\dfrac{1-18i}{2-i}\\
\implies &amp;4(x+iy)-3(x-iy)=\dfrac{1-18i}{2-i}\times \dfrac{2+i}{2+i}\\
\implies &amp;4x+4iy-3x+3iy=\dfrac{(1-18i)(2+i)}{2^2-i^2} \end{align}\b…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 02 Jul 2024 16:57:50 +0000</pubDate>
        </item>
        <item>
            <title>Question 6, Exercise 1.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-1-p6</link>
            <description>Question 6, Exercise 1.1

Solutions of Question 6 of Exercise 1.1 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 6(i)
$4-3 i$$z=4-3 i$$\bar{z}=4+3i$$3 i+8$$2+\sqrt{\dfrac{-1}{5}}$\begin{align}z=&amp;2+\sqrt{\dfrac{-1}{5}}\\
=&amp;2+\sqrt{\dfrac{1}{5}}i,\end{align}$$\bar{z}=2-\sqrt{\dfrac{1}{5}}i$$$\dfrac{5 }{2}i-\dfrac{7}{8}$$z=\dfrac{5 }{2}i-\dfrac{7}{8},$$\bar…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Jul 2024 12:40:49 +0000</pubDate>
        </item>
        <item>
            <title>Question 7, Exercise 1.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-1-p7</link>
            <description>Question 7, Exercise 1.1

Solutions of Question 7 of Exercise 1.1 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 7(i)
$11+12 i$$$z=11+12i$$\begin{align}|z|&amp;= \sqrt{(11)^2+(12)^2}\\
&amp;=\sqrt{265}\end{align}$|11+12 i|=\sqrt{265}$$(2+3 i)-(2+6 i)$$z=(2+3i)−(2+6i)$\begin{align}z&amp;=2+3i−2−6i\\
&amp;=-3i \end{align}\begin{align}
|z| &amp;= \sqrt{0^2+(-3)^2} \\
&amp;= \sqrt{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 02 Jul 2024 16:57:27 +0000</pubDate>
        </item>
        <item>
            <title>Exercise 1.2 (Solutions)</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-2</link>
            <description>Exercise 1.2 (Solutions)

The solutions of the Exercise 1.2 of book “Model Textbook of Mathematics for Class XI” published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan are given on this page. This exercise consists of the question related to real and imaginary part of complex numbers, modulus and conjugate of the complex numbers.$\operatorname{Re}(i z)=-\operatorname{Im}(z)$$\operatorname{Im}(i z)=\operatorname{Re}(z)$$$\left(z_{1} z_{2}\right)\left(z_{3} z_{4…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 27 Oct 2025 18:50:09 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 1.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-2-p1</link>
            <description>Question 1, Exercise 1.2

Solutions of Question 1 of Exercise 1.2 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 1(i)
$\operatorname{Re}(i z)=-\operatorname{Im}(z)$$$z=x+iy$$\begin{align}
iz&amp;=i(x+iy)\\
&amp;=ix-y\end{align}\begin{align}Re(iz)&amp;=-y\\
\implies Re(iz)&amp;=-Im(z)\end{align}$\operatorname{Im}(i z)=\operatorname{Re}(z)$$$z=x+iy$$\begin{align}iz&amp;=i(x+i…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Jul 2024 12:44:38 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Exercise 1.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-2-p2</link>
            <description>Question 2, Exercise 1.2

Solutions of Question 2 of Exercise 1.2 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 2
$$
\left(z_{1} z_{2}\right)\left(z_{3} z_{4}\right)=\left(z_{1} z_{3}\right)\left(z_{2} z_{4}\right)=z_{3}\left(z_{1} z_{2}\right) z_{4}
$$\begin{align}
&amp;(z_1 z_2)(z_3 z_4) \\
=&amp;(z_1 z_2)z_5 \quad \text {Let }z_5=z_3 z_4 \\
=&amp;z_1 (z_2 z_5) \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Jul 2024 12:45:03 +0000</pubDate>
        </item>
        <item>
            <title>Question 3, Exercise 1.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-2-p3</link>
            <description>Question 3, Exercise 1.2

Solutions of Question 3 of Exercise 1.2 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 3(i)
$z \in \mathbb{C}$$z$$z=\bar{z}$$$z=a+ib\quad \text{where}\quad a,b\in \mathbb{R}\, ... (1)$$$z$$\overline{z}=z$$z$$z$$b=0$\begin{align}
&amp;z=a \\
\implies &amp;\bar{z}=a \end{align}$z=\bar{z}$$\overline{z}=z$$z$\begin{align}&amp; z=\bar{z}\\
\Righ…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Jul 2024 12:53:00 +0000</pubDate>
        </item>
        <item>
            <title>Question 4, Exercise 1.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-2-p4</link>
            <description>Question 4, Exercise 1.2

Solutions of Question 4 of Exercise 1.2 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 4
$z_{1}=2-3 i$$\left|z_{1} z_{2}\right|=16$$\left|z_{2}\right|$$$z_{1}=2-3i$$\begin{align}|z_1|&amp;=\sqrt{(2)^2+(-3)^2}\\
&amp;=\sqrt{13}\end{align}\begin{align}&amp;|z_{1} z_{2}|=16\\
\Rightarrow \quad &amp;|z_{1}|| z_{2}|=16\\
\Rightarrow \quad &amp; \sqrt{13…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Jul 2024 12:54:23 +0000</pubDate>
        </item>
        <item>
            <title>Question 5, Exercise 1.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-2-p5</link>
            <description>Question 5, Exercise 1.2

Solutions of Question 5 of Exercise 1.2 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 5
$z_1$$z_2$$|z_1+z_2|^2-|z_1-z_2|^2=4Re(z_1)Re(z_2)$\begin{align}z_1&amp;=x_1+iy_1 \text{ and } z_2&amp;=x_2+iy_2\end{align}\begin{align}z_1+z_2&amp;=x_1+iy_1+x_2+iy_2\\
 &amp;=x_1+x_2+i(y_1+y_2)\\
|z_1+z_2|^2&amp;=(x_1+x_2)^2+(y_1+y_2)^2\\
 &amp;=x^2_1+x^2_2+2x_1x_…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Jul 2024 12:55:01 +0000</pubDate>
        </item>
        <item>
            <title>Question 6, Exercise 1.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-2-p6</link>
            <description>Question 6, Exercise 1.2

Solutions of Question 6 of Exercise 1.2 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 6
$\lambda$$\left|\dfrac{z_{1}}{z_{2}}+\lambda\right|=\sqrt{\lambda+2}$$z_{1}=3+i$$z_{2}=1+i$\begin{align} &amp;z_{1}=3+i\text{ and } z_{2}=1+i.\end{align}\begin{align}
\dfrac{z_1}{z_2} &amp;= \dfrac{3+i}{1+i}\\
&amp;=\dfrac{(3+i)(1-i)}{(1+i)(1-i)} \\
&amp;=\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Jul 2024 13:16:48 +0000</pubDate>
        </item>
        <item>
            <title>Question 7, Exercise 1.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-2-p7</link>
            <description>Question 7, Exercise 1.2

Solutions of Question 7 of Exercise 1.2 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 7
$\sqrt{2}|z| \geq|\operatorname{Re}(z)|+|\operatorname{Im}(z)| \quad$$\left(|x|-|y|)^{2} \geq 0\right)$\begin{align}
&amp;\left(|x|-|y|)^{2} \geq 0\right) \\
\implies &amp; |x|^2+|y|^2-2|x||y| \geq 0 \\
\implies &amp; |x|^2+|y|^2 \geq 2|x||y| \\
\implie…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Jul 2024 13:32:58 +0000</pubDate>
        </item>
        <item>
            <title>Question 8, Exercise 1.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-2-p8</link>
            <description>Question 8, Exercise 1.2

Solutions of Question 8 of Exercise 1.2 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 8(i)
$|2 z-i|=4$$x$$y$$z=x+i y$$$|2z-i|=4.$$$z=x+i y$\begin{align}
&amp; |2(x+iy)-i|=4 \\
\implies &amp; |2x+i(2y-1)|=4 \\
\implies &amp; \sqrt{(2x)^2+(2y-1)^2}=4
\end{align}\begin{align}
&amp; (2x)^2+(2y-1)^2 = 16\\
\implies &amp; 4x^2+4y^2-4y+1-16=0 \\
\implies…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 10 Jul 2024 19:37:43 +0000</pubDate>
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            <title>Question 9, Exercise 1.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-2-p9</link>
            <description>Question 9, Exercise 1.2

Solutions of Question 9 of Exercise 1.2 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 9(i)
$(2+4 i)^{-1}$$z=2+4i$\begin{align}
Re(2+4i)^{-1} &amp; = Re(z^{-1}) = \dfrac{Re(z)}{|z|^2} \\
&amp; =\dfrac{2}{2^2+4^2} = \dfrac{2}{20}\\ 
&amp;= \dfrac{1}{10}.
\end{align}\begin{align}
Im(2+4i)^{-1} &amp; = Im(z^{-1}) = -\dfrac{Im(z)}{|z|^2} \\
&amp; =-\df…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Jul 2024 19:38:59 +0000</pubDate>
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        <item>
            <title>Question 10, Exercise 1.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-2-p10</link>
            <description>Question 10, Exercise 1.2

Solutions of Question 10 of Exercise 1.2 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 10(i)
$z_{1}=-3+2 i$$$\left|z_{1}\right|=\left|-z_{1}\right|=\left|\overline{z_{!}}\right|=\left|-\overline{z_{!}}\right|.$$\begin{align}
|z_1| &amp;= \sqrt{(-3)^2 + (2)^2} \\ 
&amp;= \sqrt{9 + 4} = \sqrt{13} \,\, -- (1)
\end{align}\begin{align}
-z_…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Jul 2024 17:34:55 +0000</pubDate>
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            <title>Exercise 1.3 (Solutions)</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-3</link>
            <description>Exercise 1.3 (Solutions)

The solutions of the Exercise 1.3 of book “Model Textbook of Mathematics for Class XI” published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan are given on this page. This exercise consists of the question related to sum, product and division of the complex numbers.$z^{2}+169$$2 z^{2}+18$$3 z^{2}+363$$z^{2}+\dfrac{3}{25}$$2 z^{3}+3 z^{2}-10 z-15$$z^{3}-7 z+6$$z^{3}+2 z^{2}-23 z-60$$2 z^{3}+9 z^{2}-11 z-30$$z^{2}-7 z-8$$4 z^{2}-7 z-11$$…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 27 Oct 2025 18:51:15 +0000</pubDate>
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        <item>
            <title>Question 1, Exercise 1.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-3-p1</link>
            <description>Question 1, Exercise 1.3

Solutions of Question 1 of Exercise 1.3 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 1(i)
$z^{2}+169$\begin{align} 
&amp; z^{2} + 169 \\
= &amp; z^{2} - (13i)^2 \\
= &amp;(z + 13i)(z - 13i).
\end{align}$2 z^{2}+18$\begin{align}
&amp; 2z^2 + 18 \\
= &amp;2(z^2 - (3i)^2)\\ 
= &amp;2(z + 3i)(z - 3i)
\end{align}$3 z^{2}+363$\begin{align}
&amp; 3z^2 + 363 \\ …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 14 Jul 2024 19:35:10 +0000</pubDate>
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        <item>
            <title>Question 2, Exercise 1.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-3-p2</link>
            <description>Question 2, Exercise 1.3

Solutions of Question 2 of Exercise 1.3 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 2(i)
$z^{2}-6 z+2=0$\begin{align} &amp; z^2 - 6z + 2 = 0 \\
\implies &amp; z^2 - 2(3)(z)+9-9+2=0 \\
\implies &amp; (z - 3)^2+7= 0 \\
\implies &amp;  (z - 3)^2 = 7.
\end{align}\begin{align} &amp;z - 3 = \pm \sqrt{7} \\
 \implies &amp;z = 3 \pm \sqrt{7}\end{align}$\{3 …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 14 Jul 2024 19:41:53 +0000</pubDate>
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        <item>
            <title>Question 3, Exercise 1.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-3-p3</link>
            <description>Question 3, Exercise 1.3

Solutions of Question 3 of Exercise 1.3 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 3(i)
$\dfrac{1}{3} z^{2}+2 z-16=0$\begin{align}&amp;\dfrac{1}{3}z^{2}+2 z-16=0\\
\implies &amp;z^{2} + 6z - 48 = 0 \end{align}$$ z = \dfrac{{-b \pm \sqrt{{b^2 - 4ac}}}}{2a},$$$$a = 1,\quad  b = 6,\quad \text{and}\quad  c = -48.$$\begin{align} 
z&amp; = \d…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 14 Jul 2024 19:45:23 +0000</pubDate>
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        <item>
            <title>Question 4, Exercise 1.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-3-p4</link>
            <description>Question 4, Exercise 1.3

Solutions of Question 4 of Exercise 1.3 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 4(i)
$(1-i) z+(1+i) \omega=3 ; 2 z-(2+5 i) \omega=2+3 i$\begin{align}
&amp;(1-i) z+(1+i) \omega=3 \quad \cdots(1)\\
&amp;2 z-(2+5 i) \omega=2+3i \quad\cdots(2)
\end{align}$2$\begin{align}
&amp;(2-2i)z+(2+2i) \omega=6  \quad \cdots (3)
\end{align}$(1-i)$\b…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 15 Jul 2024 12:19:22 +0000</pubDate>
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        <item>
            <title>Exercise 1.4 (Solutions)</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-4</link>
            <description>Exercise 1.4 (Solutions)

The solutions of the Exercise 1.4 of book “Model Textbook of Mathematics for Class XI” published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan are given on this page. This exercise consists of the question related to polar form of the complex numbers.$2+i 2 \sqrt{3}$$3-i \sqrt{3}$$-2-i 2$$\dfrac{i-1}{\cos \dfrac{\pi}{3}+i \sin \dfrac{\pi}{3}}$$\left(\cos \dfrac{\pi}{6}+i \sin \dfrac{\pi}{6}\right)\left(\cos \dfrac{\pi}{3}+i \sin \dfrac…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 27 Oct 2025 18:51:55 +0000</pubDate>
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        <item>
            <title>Question 1, Exercise 1.4</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-4-p1</link>
            <description>Question 1, Exercise 1.4

Solutions of Question 1 of Exercise 1.4 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 1(i)
$2+i 2 \sqrt{3}$$z=x+iy=2 + i 2 \sqrt{3}$\begin{align} 
r &amp; = \sqrt{x^2 + y^2} = \sqrt{2^2 + (2\sqrt{3})^2} \\
 &amp; = \sqrt{4 + 12} = \sqrt{16} = 4.
\end{align}\begin{align}
\alpha &amp; = \tan^{-1}\left|\frac{y}{x}\right| = \tan^{-1}\left|\fra…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 15 Jul 2024 12:24:40 +0000</pubDate>
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        <item>
            <title>Question 2, Exercise 1.4</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-4-p2</link>
            <description>Question 2, Exercise 1.4

Solutions of Question 2 of Exercise 1.4 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 2(i)
$\left(\cos \dfrac{\pi}{6}+i \sin \dfrac{\pi}{6}\right)\left(\cos \dfrac{\pi}{3}+i \sin \dfrac{\pi}{3}\right)$$z_1=\cos \dfrac{\pi}{6}+i \sin \dfrac{\pi}{6}=e^{i\frac{\pi}{6}}$$z_2=\cos \dfrac{\pi}{3}+i \sin \dfrac{\pi}{3}=e^{i\frac{\pi}{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 05 Sep 2024 12:24:09 +0000</pubDate>
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        <item>
            <title>Question 3, Exercise 1.4</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-4-p3</link>
            <description>Question 3, Exercise 1.4

Solutions of Question 3 of Exercise 1.4 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 3(i)
$\left(x_{1}+i y_{1}\right)\left(x_{2}+i y_{2}\right)\left(x_{3}+i y_{3}\right) \ldots\left(x_{n}+i y_{n}\right)=a+i b$$\left(x_{1}^{2}+y_{1}^{2}\right)\left(x_{2}^{2}+y_{2}^{2}\right)\left(x_{3}^{2}+y_{3}^{2}\right) \ldots\left(x_{n}^{2}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 17 Jul 2024 16:39:59 +0000</pubDate>
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        <item>
            <title>Question 4, Exercise 1.4</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-4-p4</link>
            <description>Question 4, Exercise 1.4

Solutions of Question 4 of Exercise 1.4 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 4
$\dfrac{1+z}{1-z}=\cos 2 \theta+i \sin 2 \theta$$z=i \tan \theta$\begin{align}&amp;\dfrac{1+z}{1-z}=\cos 2 \theta+i \sin 2 \theta\\
\implies &amp;\dfrac{1+z}{1-z}=e^{i2\theta}\\
\implies &amp;(1+z)=(1-z)e^{i2\theta}\\
\implies &amp;z+z e^{i2\theta}=e^{i2\th…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 15 Jul 2024 12:40:46 +0000</pubDate>
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        <item>
            <title>Question 5, Exercise 1.4</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-4-p5</link>
            <description>Question 5, Exercise 1.4

Solutions of Question 5 of Exercise 1.4 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 5
$\cos \alpha+\cos \beta+\cos \gamma=\sin \alpha+\sin \beta+\sin \gamma=0$$\cos 3 \alpha+\cos 3 \beta+\cos 3 \gamma=3 \cos (\alpha+\beta+\gamma)$$\sin 3 \alpha+\sin 3 \beta+\sin 3 \gamma=3 \sin (\alpha+\beta+\gamma)$\begin{align}
\cos \alpha …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 15 Jul 2024 12:41:11 +0000</pubDate>
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        <item>
            <title>Question 6(i-ix), Exercise 1.4</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-4-p6</link>
            <description>Question 6(i-ix), Exercise 1.4

Solutions of Question 6(i-ix) of Exercise 1.4 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\sqrt{2}\left(\cos 315^{\circ}+i \sin 315^{\circ}\right)$\begin{align}
&amp;\sqrt{2}\left(\cos 315^{\circ}+i \sin 315^{\circ}\right) \\
=&amp; \sqrt{2} \left(\dfrac{1}{\sqrt{2}}-\dfrac{i}{\sqrt{2}} \right) \\
=&amp; 1-i.
\end{align}$5\left(\cos 210^{\ci…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 17 Jul 2024 12:40:31 +0000</pubDate>
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        <item>
            <title>Question 6(x-xvii), Exercise 1.4</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-4-p7</link>
            <description>Question 6(x-xvii), Exercise 1.4

Solutions of Question 6(x-xvii) of Exercise 1.4 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $7 \sqrt{2}\left(\cos \dfrac{5 \pi}{4}+i \sin \dfrac{5 \pi}{4}\right)$$10 \sqrt{2}\left(\cos \dfrac{7 \pi}{4}+i \sin \dfrac{7 \pi}{4}\right)$$2\left(\cos\dfrac{5\pi}{2}+i \sin \dfrac{5\pi}{2}\right)$$\dfrac{1}{\sqrt{2}}\left(\cos \dfrac{\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 17 Jul 2024 12:40:53 +0000</pubDate>
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        <item>
            <title>Question 7, Exercise 1.4</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-4-p8</link>
            <description>Question 7, Exercise 1.4

Solutions of Question 7 of Exercise 1.4 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 7(i)
$\arg (z-1)=-\dfrac{\pi}{4}$$z=x+iy$\begin{align*}
&amp;\arg (z-1)=-\dfrac{\pi}{4} \\
\implies &amp; \arg(x+iy-1) = -\dfrac{\pi}{4} \\
\implies &amp; \arg(x-1+iy) = -\dfrac{\pi}{4} \\
\implies &amp; \tan^{-1}\left(\dfrac{y}{x-1}\right) = -\dfrac{\pi}{4} …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 17 Jul 2024 12:41:24 +0000</pubDate>
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        <item>
            <title>Question 8, Exercise 1.4</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-4-p9</link>
            <description>Question 8, Exercise 1.4

Solutions of Question 8 of Exercise 1.4 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 8(i)
$0.004 \mathrm{~mm}$$\dfrac{\pi}{4}$$$x_{\max}=0.004, \quad \theta=\dfrac{\pi}{4}.$$\begin{align}
x&amp;=x_{\max} e^{i\theta} \\
&amp;=0.004 e^{i\dfrac{\pi}{4}} \\
&amp;=\frac{4}{1000} \left(\cos\left(\dfrac{\pi}{4}\right) +i \sin\left(\dfrac{\pi}{4}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 17 Jul 2024 12:41:56 +0000</pubDate>
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        <item>
            <title>Question 10, Exercise 1.4</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/ex1-4-p11</link>
            <description>Question 10, Exercise 1.4

Solutions of Question 10 of Exercise 1.4 of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 10(i)
$Z$$E=(-50+100 i)$$I=(-6-2 i)$$E=(-50+100 i)$$I=(-6-2 i)$$$ E = I \times Z $$$$(-50+100 i)= (-6-2 i) \times Z $$\begin{align}
\implies Z &amp; = \dfrac{-50+100 i}{-6-2 i} \\
&amp; = \dfrac{(-50+100 i)(-6+2i)}{(-6-2 i)(-6+2i)}\\
&amp; = \dfrac{300-…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 17 Jul 2024 12:47:07 +0000</pubDate>
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        <item>
            <title>Question 1, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/re-ex-p1</link>
            <description>Question 1, Review Exercise

Solutions of Question 1 of Review Exercise of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\operatorname{part}(\mathrm{s})$$z$$z$$(0,0)$$(1,0)$$(0,1)$$(1,1)$$(0,0)$$z$$|z|$$1 / z$$-z$$\bar{z}$$\bar{z}$$x$$y$$x y$$y$$z_{1}=3+2 i$$z_{2}=5+6 i$$z_{1}&gt;z_{2}$$z_{1}&lt;z_{2}$$\overline{z_{1}}=\overline{z_{2}}$$\overline{z_{1}}=-\overline{z_{2}}$…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 17 Jul 2024 12:53:04 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/re-ex-p2</link>
            <description>Question 2, Review Exercise

Solutions of Question 2 of Review Exercise of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $i^{2}+i^{4}+i^{6}+\cdots+i^{100}$\begin{align*}
&amp; i^{2}+i^{4}+i^{6}+\ldots+i^{100} \\
=&amp; i^2 + (i^2)^2 + (i^2)^3 + (i^2)^4 + \ldots +(i^2)^{49} +(i^2)^{50} \\
=&amp; -1 + (-1)^2 + (-1)^3 + (-1)^4 + \ldots + (-1)^{49}+(-1)^{50} \\
=&amp; -1+1-1+1- \ldots -…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 17 Jul 2024 12:53:23 +0000</pubDate>
        </item>
        <item>
            <title>Question 3, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/re-ex-p3</link>
            <description>Question 3, Review Exercise

Solutions of Question 3 of Review Exercise of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $3 x^{2}+108$\begin{align*}
&amp; 3 x^{2}+108\\
=&amp;3 (x^{2}+36)\\
=&amp;3 (x^{2}-(6i)^2)\\
=&amp;3 (x+6i)(x-6i)
\end{align*}$4 x^{2}+40$\begin{align*}
&amp;4 x^{2}+40\\
=&amp;4 (x^{2}+10)\\
=&amp;4 (x^{2}+(\sqrt{10}i)^2)\\
=&amp;4 (x+\sqrt{10}i)(x-\sqrt{10}i)
\end{align*}</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 17 Jul 2024 12:53:46 +0000</pubDate>
        </item>
        <item>
            <title>Question 4, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/re-ex-p4</link>
            <description>Question 4, Review Exercise

Solutions of Question 4 of Review Exercise of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $z=x+i y$$\left|\dfrac{z+2 i}{z-2 i}\right|=1$$z = x + iy$\begin{align*}
&amp; \left|\dfrac{z + 2i}{z - 2i}\right| = 1\\
\implies &amp; |z + 2i| = |z - 2i|\\
\implies &amp; |x + i(y + 2)| = |x + i(y - 2)|\\
\implies &amp;  \sqrt{x^2 + (y + 2)^2} = \sqrt{x^2 + (y -…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 17 Jul 2024 12:54:02 +0000</pubDate>
        </item>
        <item>
            <title>Question 5, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/re-ex-p5</link>
            <description>Question 5, Review Exercise

Solutions of Question 5 of Review Exercise of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $z$$(z-3 i)(2+5 i)=3-4 i$$z$$(z-3 i)(2+5 i)=3-4 i$\begin{align*}
&amp;(z-3 i)(2+5 i)=3-4 i \\
\implies &amp; z-3 i=\dfrac{3-4 i}{2+5 i} \\
\implies &amp; z-3 i=\dfrac{(3-4 i)(2-5i)}{(2+5 i)(2-5i)}\\
\implies &amp; z-3 i=\dfrac{6-20-15i-8i}{4+25}\\
\implies &amp; z-3 i…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 17 Jul 2024 16:47:30 +0000</pubDate>
        </item>
        <item>
            <title>Question 6, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/re-ex-p6</link>
            <description>Question 6, Review Exercise

Solutions of Question 6 of Review Exercise of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\left[\dfrac{1}{i^{10}}+(2-i)^{2}+\sqrt{-25}\right]^{3}$\begin{align*}
&amp;\left[\dfrac{1}{i^{10}} + (2 - i)^2 + \sqrt{-25}\right]^3\\
=&amp;\left[\dfrac{1}{(i^2)^5} + ( 4 - 4i + i^2) + 5i \right]^3\\
=&amp;\left[\dfrac{1}{(-1)^5} + ( 4 - 4i -1) + 5i \right]…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 17 Jul 2024 16:56:04 +0000</pubDate>
        </item>
        <item>
            <title>Question 7, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/re-ex-p7</link>
            <description>Question 7, Review Exercise

Solutions of Question 7 of Review Exercise of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $2 z^{2}-11 z+16=0$\begin{align*}
&amp;2 z^{2}-11 z+16=0\\
\implies&amp;z^2 - \dfrac{11}{2}z + 8 = 0\\
\implies&amp; z^2 - \dfrac{11}{2}z = -8\\
\implies&amp; z^2 - 2z\dfrac{11}{4}z + \dfrac{121}{16} = -8 + \dfrac{121}{16}\\
\implies&amp;\left(z-\dfrac{11}{4}\right)^2…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 17 Jul 2024 16:59:42 +0000</pubDate>
        </item>
        <item>
            <title>Question 8, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/re-ex-p8</link>
            <description>Question 8, Review Exercise

Solutions of Question 8 of Review Exercise of Unit 01: Complex Numbers. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\sqrt{2}+i \sqrt{2}$$\theta=45^{\circ}$$$x= \sqrt{2} + i \sqrt{2}, \quad \theta=\dfrac{\pi}{4}.$$$x_{\max}$\begin{align}
&amp;x=x_{\max} e^{i\theta} \\
\implies &amp; \sqrt{2} + i \sqrt{2}=x_{\max} e^{i\dfrac{\pi}{4}} \\
\implies &amp; x_{\max} \left(\cos\dfr…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 17 Jul 2024 17:13:41 +0000</pubDate>
        </item>
        <item>
            <title>Review Exercise 1 (Solutions)</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit01/rev-ex</link>
            <description>Review Exercise 1 (Solutions)

The solutions of the Review Exercise 1 of book “Model Textbook of Mathematics for Class XI” published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan are given on this page. This exercise consists of the question related to polar form of the complex numbers. $i^{2}+i^{4}+i^{6}+\cdots+i^{100}$$\left|\dfrac{(3-2 i)(1+i)}{2-3 i}\right|$$|\overline{(3-2 i)(4-i)}|$$\left(\dfrac{3+5 i}{2-3 i}\right)^{-1}$$3 x^{2}+108$$4 x^{2}+40$$z=x+i y$…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 27 Oct 2025 18:52:39 +0000</pubDate>
        </item>
        <item>
            <title>Exercise 2.1 (Solutions)</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-1</link>
            <description>Exercise 2.1 (Solutions)

The solutions of the Exercise 2.1 of book “Model Textbook of Mathematics for Class XI” published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan are given on this page. This exercise consists of the question related to order, different type of matrices and transpose of matrix.$A=\left[\begin{array}{lll}1 &amp; 3 &amp; 0 \\ 2 &amp; 0 &amp; 1\end{array}\right]$$B=\left[\begin{array}{ll}1 &amp; 2 \\ 2 &amp; 3 \\ 3 &amp; 4\end{array}\right]$$C=\left[\begin{array}{l}1 \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 08 Feb 2026 16:35:15 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 2.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-1-p1</link>
            <description>Question 1, Exercise 2.1

Solutions of Question 1 of Exercise 2.1 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $A=\left[\begin{array}{lll}1 &amp; 3 &amp; 0 \\ 2 &amp; 0 &amp; 1\end{array}\right]$\begin{align}\text{Order of A}&amp;= 2\times 3\end{align}$B=\left[\begin{array}{ll}1 &amp; 2 \\ 2 &amp; 3 \\ 3 &amp; 4\end{array}\right]$\begin{align}\text{Order of B}&amp;= 3\times 2\end{align}$C…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 27 Jul 2024 09:35:52 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Exercise 2.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-1-p2</link>
            <description>Question 2, Exercise 2.1

Solutions of Question 2 of Exercise 2.1 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\quad A=\left[\begin{array}{lll}3 &amp; 6 &amp; 2 \\ 2 &amp; 1 &amp; 9\end{array}\right]$$B=\left[\begin{array}{ll}\frac{1}{3} &amp; 1 \\ 2 &amp; 6\end{array}\right]$$C=\left[\begin{array}{l}3 \\ 2 \\ 8\end{array}\right]$$D=\left[\begin{array}{lll}1 &amp; 6 &amp; 9 \\ 2 &amp; 0 …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 27 Jul 2024 09:36:13 +0000</pubDate>
        </item>
        <item>
            <title>Question 3, Exercise 2.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-1-p3</link>
            <description>Question 3, Exercise 2.1

Solutions of Question 3 of Exercise 2.1 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $$A=\begin{bmatrix}
3 &amp; 0 &amp; 0 \\
0 &amp; 1 &amp; 0 \\
2 &amp; 6 &amp; 0
\end{bmatrix}$$$$B=\begin{bmatrix}
-6 &amp; 0 &amp; 0 \\
0 &amp; -6 &amp; 0 \\
0 &amp; 0 &amp; -6
\end{bmatrix}$$$$C=\begin{bmatrix}
1 &amp; 0 \\
2 &amp; 0
\end{bmatrix}$$$$D=\begin{bmatrix}
1 &amp; 0 &amp; 0 \\
0 &amp; 1 &amp; 0 \\
0 &amp;…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 27 Jul 2024 09:36:33 +0000</pubDate>
        </item>
        <item>
            <title>Question 4, Exercise 2.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-1-p4</link>
            <description>Question 4, Exercise 2.1

Solutions of Question 4 of Exercise 2.1 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $$
A=\left[\begin{array}{ccc}
2 &amp; 0 \\
\sqrt{5} &amp; 6 \\
1 &amp; 9
\end{array}\right]$$$$
A^t=\begin{bmatrix}
2 &amp; \sqrt{5} &amp; 1 \\
0 &amp; 6 &amp; 9
\end{bmatrix}$$$$B=\left[\begin{array}{cccc}
1 &amp; 6 &amp; 2 &amp; 0
\end{array}\right] $$$$B^t=\left[\begin{array}{c}
1…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 27 Jul 2024 09:36:55 +0000</pubDate>
        </item>
        <item>
            <title>Exercise 2.2 (Solutions)</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-2</link>
            <description>Exercise 2.2 (Solutions)

The solutions of the Exercise 2.2 of book “Model Textbook of Mathematics for Class XI” published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan are given on this page. This exercise consists of the question related to sum, product and different operations on matrices.$A=\left[a_{i j}\right]$$2 \times 2$$a_{i j}=\dfrac{i+3 j}{2}$$a_{i j}=\dfrac{i \times l}{2}$$a_{i j}=\dfrac{i}{j}$$a_{i j}=\dfrac{2 i-3 j}{3}$$B=\left[a_{\ell}\right]$$3 \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 08 Feb 2026 16:40:19 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-2-p1</link>
            <description>Question 1, Exercise 2.2

Solutions of Question 1 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $A=\left[a_{i j}\right]$$2 \times 2$$a_{i j}=\dfrac{i+3 j}{2}$\( a_{ij} = \dfrac{i + 3j}{2} \)\( i = 1, j = 1 \)\[
a_{11} = \dfrac{1 + 3 \cdot 1}{2} = \dfrac{1 + 3}{2} = \dfrac{4}{2} = 2
\]\( i = 1, j = 2 \)\[
a_{12} = \dfrac{1 + 3 \cdot 2}{2} …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 30 Jul 2024 07:26:46 +0000</pubDate>
        </item>
        <item>
            <title>Question 3, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-2-p2</link>
            <description>Question 3, Exercise 2.2

Solutions of Question 3 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $A=\left[\begin{array}{ccc}3 &amp; -1 &amp; 2 \\ 0 &amp; 6 &amp; 1 \\ -1 &amp; 0 &amp; -3\end{array}\right]$$B=\left[\begin{array}{ccc}2 &amp; 1 &amp; 7 \\ 0 &amp; 2 &amp; -1 \\ -3 &amp; 4 &amp; 2\end{array}\right]$$C$$A+B+C=0$$$A+B+C=0,$$$$C=-A-B.$$\begin{align*}
C&amp;=-\begin{bmatrix}3 &amp; -1 &amp;…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 30 Jul 2024 07:29:12 +0000</pubDate>
        </item>
        <item>
            <title>Question 3, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-2-p3</link>
            <description>Question 3, Exercise 2.2

Solutions of Question 3 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $A=\left[\begin{array}{ccc}3 &amp; -1 &amp; 2 \\ 0 &amp; 6 &amp; 1 \\ -1 &amp; 0 &amp; -3\end{array}\right]$$B=\left[\begin{array}{ccc}2 &amp; 1 &amp; 7 \\ 0 &amp; 2 &amp; -1 \\ -3 &amp; 4 &amp; 2\end{array}\right]$$C$$A+B+C=0$$$A+B+C=0,$$$$C=-A-B.$$\begin{align*}
C&amp;=-\begin{bmatrix}3 &amp; -1 &amp;…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 30 Jul 2024 07:30:34 +0000</pubDate>
        </item>
        <item>
            <title>Question 4, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-2-p4</link>
            <description>Question 4, Exercise 2.2

Solutions of Question 4 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $A$\begin{align}\left[\begin{array}{cc} 2 &amp; 1 \\  3 &amp; 2 \end{array}\right]A\left[\begin{array}{cc} 1 &amp; 3 \\  2 &amp; 4 \end{array}\right]&amp;=\left[\begin{array}{cc} 1 &amp; 0 \\  0 &amp; 1 \end{array}\right]\end{align}$ B = \left[\begin{array}{cc} 2 &amp; 1 \\ 3…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 30 Jul 2024 07:29:39 +0000</pubDate>
        </item>
        <item>
            <title>Question 5, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-2-p5</link>
            <description>Question 5, Exercise 2.2

Solutions of Question 5 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $X=\left[\begin{array}{lll}1 &amp; 2 &amp; 2 \\ 2 &amp; 1 &amp; 2 \\ 2 &amp; 2 &amp; 1\end{array}\right]$$X^{2}-4 X-5 I=0$\begin{align}L.H.S. &amp; =X^{2}-4 X-5 I \\
&amp;=\begin{bmatrix}
1 &amp; 2 &amp; 2 \\
2 &amp; 1 &amp; 2 \\
2 &amp; 2 &amp; 1
\end{bmatrix}
\begin{bmatrix}
1 &amp; 2 &amp; 2 \\
2 &amp; 1 &amp; 2…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 19 Aug 2024 16:11:12 +0000</pubDate>
        </item>
        <item>
            <title>Question 6, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-2-p6</link>
            <description>Question 6, Exercise 2.2

Solutions of Question 6 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $A=\left[\begin{array}{cc}2 &amp; 1 \\ 3 &amp; -3\end{array}\right]$$\alpha$$\beta$$A^{2}+\alpha I=\beta A$\begin{align}
&amp; A^{2}+\alpha I=\beta A\\
\implies &amp;\begin{bmatrix}
2 &amp; 1 \\
3 &amp; -3
\end{bmatrix}
\begin{bmatrix}
2 &amp; 1 \\
3 &amp; -3
\end{bmatrix}+\a…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 19 Aug 2024 16:24:24 +0000</pubDate>
        </item>
        <item>
            <title>Question 7, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-2-p7</link>
            <description>Question 7, Exercise 2.2

Solutions of Question 7 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $A=\left[\begin{array}{ll}x &amp; 0 \\ y &amp; 1\end{array}\right]$$n, A^{n}=\left[\begin{array}{cc}x^{n} &amp; 0 \\ \dfrac{y\left(x^{n}-1\right)}{x-1} &amp; 1\end{array}\right]$$$A = \begin{bmatrix} x &amp; 0 \\ y &amp; 1 \end{bmatrix}.$$$n = 1$\begin{align}A^1 =\beg…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 19 Aug 2024 16:42:50 +0000</pubDate>
        </item>
        <item>
            <title>Question 8, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-2-p8</link>
            <description>Question 8, Exercise 2.2

Solutions of Question 8 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $A$$B$$2 \times 3$$3 \times 2$$(A B)^{t}=B^{t} A^{t}$\( A \)\( B \)\( 2 \times 3 \)\( 3 \times 2 \)\begin{align*}
	A &amp;= \begin{bmatrix}
	a_{11} &amp; a_{12} &amp; a_{13} \\
	a_{21} &amp; a_{22} &amp; a_{23}
\end{bmatrix}\\
B &amp;= \begin{bmatrix}
	b_{11} &amp; b_{12}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 19 Aug 2024 16:43:59 +0000</pubDate>
        </item>
        <item>
            <title>Question 9, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-2-p9</link>
            <description>Question 9, Exercise 2.2

Solutions of Question 9 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $A$$B$$3 \times 3$$(A+B)^{t}=A^{t}+B^{t}$\begin{align*}
A &amp;= \begin{pmatrix} 
a_{11} &amp; a_{12} &amp; a_{13} \\ 
a_{21} &amp; a_{22} &amp; a_{23} \\ 
a_{31} &amp; a_{32} &amp; a_{33} 
\end{pmatrix} \\
B &amp;= \begin{pmatrix} 
b_{11} &amp; b_{12} &amp; b_{13} \\ 
b_{21} &amp; b_{22…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 19 Aug 2024 16:44:43 +0000</pubDate>
        </item>
        <item>
            <title>Question 10, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-2-p10</link>
            <description>Question 10, Exercise 2.2

Solutions of Question 10 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $A$$B$$A B=B$$B A=A$$A^{2}+B^{2}$$$AB = B$$$$BA = A$$\begin{align*}
A^2 &amp;= AA\\
&amp; = A(BA)\\
&amp;=(AB)A\\
&amp;=BA\\
&amp;=A
\end{align*}\begin{align*}
B^2&amp;= BB \\
&amp;=B(AB)\\
&amp; = (BA)B\\
&amp;=AB\\
&amp;=B\end{align*}$$A^2 + B^2 = A + B$$$AB = B$$BA = A$$$A^2 + B…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 19 Aug 2024 16:47:00 +0000</pubDate>
        </item>
        <item>
            <title>Question 11, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-2-p11</link>
            <description>Question 11, Exercise 2.2

Solutions of Question 11 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $A=\left[a_{i j}\right]$$3 \times 3$$a_{i j}=i^{2}-j^{2}$$A$$A=\left[a_{i j}\right]$$a_{ij}=a+{ji}$$a_{ij}=-a_{ji}$$a_{i j}=i^{2}-j^{2}$\begin{align}
a_{ji} &amp; = j^2 -i^2 \\
&amp;= - (i^2 -j^2) \\
&amp;= - a_{ij}
\end{align}$a_{ij}=-a_{ji}$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 19 Aug 2024 16:55:20 +0000</pubDate>
        </item>
        <item>
            <title>Question 12, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-2-p12</link>
            <description>Question 12, Exercise 2.2

Solutions of Question 12 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $A$$\left(A^{n}\right)^{t}=\left(A^{t}\right)^{n}$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 19 Aug 2024 16:58:16 +0000</pubDate>
        </item>
        <item>
            <title>Question 13, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-2-p13</link>
            <description>Question 13, Exercise 2.2

Solutions of Question 13 of Exercise 2.2 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $X$$Y$$2 X-Y=\left[\begin{array}{ccc}1 &amp; 6 &amp; -3 \\ 2 &amp; 1 &amp; 7\end{array}\right]$$X+3 Y=\left[\begin{array}{ccc}4 &amp; 3 &amp; 2 \\ 1 &amp; -3 &amp; 0\end{array}\right]$\begin{align*}
2X - Y = \begin{pmatrix} 1 &amp; 6 &amp; -3 \\ 2 &amp; 1 &amp; 7 \end{pmatrix} \cdots (i)\\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 19 Aug 2024 16:58:35 +0000</pubDate>
        </item>
        <item>
            <title>Exercise 2.3 (Solutions)</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-3</link>
            <description>Exercise 2.3 (Solutions)

The solutions of the Exercise 2.3 of book “Model Textbook of Mathematics for Class XI” published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan are given on this page. This exercise consists of the question related to determinant and inverse of the matrix.$\left[\begin{array}{ccc}2 &amp; 3 &amp; 1 \\ 1 &amp; -1 &amp; 2 \\ 4 &amp; 1 &amp; 2\end{array}\right]$$\left[\begin{array}{ccc}\cos \theta &amp; -\sin \theta &amp; 0 \\ \sin \theta &amp; \cos \theta &amp; 0 \\ 0 &amp; 0 &amp; 1\en…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 08 Feb 2026 16:44:16 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 2.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-3-p1</link>
            <description>Question 1, Exercise 2.3

Solutions of Question 1 of Exercise 2.3 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\left[\begin{array}{ccc}2 &amp; 3 &amp; 1 \\ 1 &amp; -1 &amp; 2 \\ 4 &amp; 1 &amp; 2\end{array}\right]$\begin{align*}
A &amp;= \left[\begin{array}{ccc}2 &amp; 3 &amp; 1 \\ 1 &amp; -1 &amp; 2 \\ 4 &amp; 1 &amp; 2\end{array}\right]\\
|A|&amp;=2(-2-2)-3(2-8)+1(1+4)\\
\implies |A|&amp;=-8+18+5\\
\implies |…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 23 Aug 2024 09:03:34 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Exercise 2.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-3-p2</link>
            <description>Question 2, Exercise 2.3

Solutions of Question 2 of Exercise 2.3 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\left[\begin{array}{lll}3 &amp; 2 &amp; 3 \\ 4 &amp; 5 &amp; 1 \\ 2 &amp; 1 &amp; 0\end{array}\right]$\(R_1\)\(a_{11} = 3\)\(a_{12} = 2\)\(a_{13} = 3\)\begin{align*}
A &amp;= \left[\begin{array}{ccc} 3 &amp; 2 &amp; 3 \\ 4 &amp; 5 &amp; 1 \\ 2 &amp; 1 &amp; 0 \end{array}\right]\\
&amp; A_{11} = (-1…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 23 Aug 2024 09:04:07 +0000</pubDate>
        </item>
        <item>
            <title>Question 3, Exercise 2.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-3-p3</link>
            <description>Question 3, Exercise 2.3

Solutions of Question 3 of Exercise 2.3 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\left[\begin{array}{ccc}3 &amp; 1 &amp; 2 \\ 2 &amp; 3 &amp; 1 \\ -4 &amp; 1 &amp; -3\end{array}\right]$\begin{align*}
A &amp;= \left[\begin{array}{ccc} 3 &amp; 1 &amp; 2 \\ 2 &amp; 3 &amp; 1 \\ -4 &amp; 1 &amp; -3\end{array}\right]\end{align*}\(3 \times 3\)\begin{align*}
|A| &amp;= 3(3 \cdot (-3) …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 23 Aug 2024 09:04:42 +0000</pubDate>
        </item>
        <item>
            <title>Question 4, Exercise 2.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-3-p4</link>
            <description>Question 4, Exercise 2.3

Solutions of Question 4 of Exercise 2.3 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\lambda$$\left[\begin{array}{lll}\lambda &amp; 1 &amp; 3 \\ 2 &amp; 1 &amp; 8 \\ 0 &amp; 3 &amp; 1\end{array}\right]$\begin{align*}
A &amp;= \left[\begin{array}{ccc}
\lambda &amp; 1 &amp; 3 \\
2 &amp; 1 &amp; 8 \\
0 &amp; 3 &amp; 1
\end{array}\right]\\
|A| &amp;= \lambda \cdot (-23) - 1 \cdot 2 + 3…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 23 Aug 2024 09:05:13 +0000</pubDate>
        </item>
        <item>
            <title>Question 5, Exercise 2.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-3-p5</link>
            <description>Question 5, Exercise 2.3

Solutions of Question 5 of Exercise 2.3 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\left[\begin{array}{ccc}1 &amp; -1 &amp; 1 \\ 2 &amp; 1 &amp; -1 \\ 1 &amp; -2 &amp; -1\end{array}\right]$\begin{align*}
A &amp;= \left[\begin{array}{ccc}
1 &amp; -1 &amp; 1 \\
2 &amp; 1 &amp; -1 \\
1 &amp; -2 &amp; -1
\end{array}\right]\\
|A|&amp;=  1 [-1 - 2] + 1 [-2 + 1] + 1 [-4 - 1] \\
&amp;= 1 \cd…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 23 Aug 2024 09:05:37 +0000</pubDate>
        </item>
        <item>
            <title>Question 6, Exercise 2.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-3-p6</link>
            <description>Question 6, Exercise 2.3

Solutions of Question 6 of Exercise 2.3 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $A=\left[\begin{array}{ccc}2 &amp; 1 &amp; -3 \\ 0 &amp; 1 &amp; 0 \\ 2 &amp; 1 &amp; 6\end{array}\right]$$A^{-1}$$A A^{-1}=A^{-1} A=I_{3}$\begin{align*} A &amp;= \begin{bmatrix}
2 &amp; 1 &amp; -3 \\
0 &amp; 1 &amp; 0 \\
2 &amp; 1 &amp; 6
\end{bmatrix} \end{align*}$ A^{-1} $$ A $\begin{align*}
…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 23 Aug 2024 09:41:19 +0000</pubDate>
        </item>
        <item>
            <title>Question 7, Exercise 2.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-3-p7</link>
            <description>Question 7, Exercise 2.3

Solutions of Question 7 of Exercise 2.3 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $(A B)^{-1}=B^{-1} A^{-1}$$A=\left[\begin{array}{ll}2 &amp; 1 \\ 8 &amp; 6\end{array}\right]$$B=\left[\begin{array}{ll}3 &amp; 2 \\ 0 &amp; 2\end{array}\right]$\begin{align*}
A &amp;= \left[\begin{array}{ll}2 &amp; 1 \\ 8 &amp; 6\end{array}\right] \\	
|A|&amp; = 12 - 8 = 4\\	…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 23 Aug 2024 09:48:00 +0000</pubDate>
        </item>
        <item>
            <title>Exercise 2.4 (Solutions)</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-4</link>
            <description>Exercise 2.4 (Solutions)

The solutions of the Exercise 2.4 of book “Model Textbook of Mathematics for Class XI” published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan are given on this page. This exercise consists of the question related to the determinant and properties of the determinant.$\left|\begin{array}{lll}9 &amp; 27 &amp; 36 \\ 18 &amp; 54 &amp; 24 \\ 27 &amp; 81 &amp; 28\end{array}\right|=0$$\left|\begin{array}{lll}1 / a &amp; b c &amp; b+c \\ 1 / b &amp; a c &amp; a+c \\ 1 / c &amp; a b &amp; a+…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 08 Feb 2026 16:46:40 +0000</pubDate>
        </item>
        <item>
            <title>Exercise 2.5 (Solutions)</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-5</link>
            <description>Exercise 2.5 (Solutions)

The solutions of the Exercise 2.5 of book “Model Textbook of Mathematics for Class XI” published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan are given on this page. This exercise consists of the question related to solving system of the equation of three variables by using matrices.$\left[\begin{array}{ccc}1 &amp; 3 &amp; 5 \\ -6 &amp; 8 &amp; 3 \\ -4 &amp; 6 &amp; 5\end{array}\right]$$\left[\begin{array}{ll}2 &amp; 1 \\ 3 &amp; 2 \\ 1 &amp; 9\end{array}\right]$$\left[…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 08 Feb 2026 16:50:14 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 2.5</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-5-p1</link>
            <description>Question 1, Exercise 2.5

Solutions of Question 1 of Exercise 2.5 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\left[\begin{array}{ccc}1 &amp; 3 &amp; 5 \\ -6 &amp; 8 &amp; 3 \\ -4 &amp; 6 &amp; 5\end{array}\right]$\begin{align*}
&amp; \quad \left[\begin{array}{ccc}1 &amp; 3 &amp; 5 \\ -6 &amp; 8 &amp; 3 \\ -4 &amp; 6 &amp; 5\end{array}\right]\\
\sim &amp; \text{R}
\left[\begin{array}{ccc}
1 &amp; 3 &amp; 5 \\
0 &amp; …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 04 Sep 2024 03:01:24 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Exercise 2.5</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-5-p2</link>
            <description>Question 2, Exercise 2.5

Solutions of Question 2 of Exercise 2.5 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\left[\begin{array}{ccc}5 &amp; 9 &amp; 3 \\ 3 &amp; -5 &amp; 6 \\ 2 &amp; 10 &amp; 6\end{array}\right]$\begin{align*}&amp;\quad\left[ \begin{array}{ccc}
5 &amp; 9 &amp; 3 \\ 
3 &amp; -5 &amp; 6 \\ 
2 &amp; 10 &amp; 6 
\end{array} \right]\\
\sim &amp; \text{R}\left[ \begin{array}{ccc}
1 &amp; \frac{9}{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 04 Sep 2024 03:01:56 +0000</pubDate>
        </item>
        <item>
            <title>Question 3, Exercise 2.5</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-5-p3</link>
            <description>Question 3, Exercise 2.5

Solutions of Question 3 of Exercise 2.5 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\left[\begin{array}{ccc}0 &amp; -1 &amp; -1 \\ -1 &amp; 3 &amp; 0 \\ 1 &amp; -1 &amp; 4\end{array}\right]$$A A^{-1}=A^{-1} A=I$\begin{align*}
A&amp;=\left[ \begin{array}{ccc}
0 &amp; -1 &amp; -1  \\ 
-1 &amp; 3 &amp; 0  \\ 
1 &amp; -1 &amp; 4 
\end{array} \right]\\
|A|&amp;=0+1(-4)-1(1-3)\\
&amp;=-4+3\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 04 Sep 2024 03:02:35 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 2.6</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-6-p1</link>
            <description>Question 1, Exercise 2.6

Solutions of Question 1 of Exercise 2.6 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $ 2 x_{1}-3 x_{2}+4 x_{3}=0$$x_{1}-2 x_{2}+3 x_{3}=0$$4 x_{1}+x_{2}-6 x_{3}=0$\begin{align*}
&amp;2 x_{1}-3 x_{2}+4 x_{3}=0\cdots (i)\\
&amp;x_{1}-2 x_{2}+3 x_{3}=0\cdots (ii)\\
&amp;4 x_{1}+x_{2}-6 x_{3}=0\cdots (iii)\\
\end{align*}\begin{align*}
A &amp;= \le…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 04 Sep 2024 03:03:49 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Exercise 2.6</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-6-p2</link>
            <description>Question 2, Exercise 2.6

Solutions of Question 2 of Exercise 2.6 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\lambda$$\lambda$$2 x_{1}-\lambda x_{2}+x_{3}=0$$2 x_{1}+3 x_{2}-x_{3}=0$$3 x_{1}-2 x_{2}+4 x_{3}=0$\begin{align*}
&amp;2 x_{1}-\lambda x_{2}+x_{3}=0 \cdots(i)\\
&amp;2 x_{1}+3 x_{2}-x_{3}=0\cdots(ii)\\
&amp;3 x_{1}-2 x_{2}+4 x_{3}=0\cdots(iii)\\
\end{ali…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 04 Sep 2024 03:04:14 +0000</pubDate>
        </item>
        <item>
            <title>Question 3, Exercise 2.6</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-6-p3</link>
            <description>Question 3, Exercise 2.6

Solutions of Question 3 of Exercise 2.6 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $2 x+3 y+4 z=2$$2 x+y+z=5$$3 x-2 y+z=-3$\begin{align*}
\begin{aligned}
2x + 3y + 4z &amp;= 2 \\
2x + y + z &amp;= 5 \\
3x - 2y + z &amp;= -3
\end{aligned}\end{align*}\begin{align*}
A_{b} &amp;=\quad \left[\begin{array}{cccc}
2 &amp; 3 &amp; 4 &amp; 2 \\
2 &amp; 1 &amp; 1 &amp; 5 \\
3…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 04 Sep 2024 03:11:14 +0000</pubDate>
        </item>
        <item>
            <title>Question 4, Exercise 2.6</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-6-p4</link>
            <description>Question 4, Exercise 2.6

Solutions of Question 4 of Exercise 2.6 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $2 x_{1}-x_{2}-x_{3}=2$$3 x_{1}-4 x_{2}+3 x_{3}=7$$4 x_{1}+2 x_{2}-5 x_{3}=10$\begin{align*}
2x_1 - x_2 - x_3 &amp;= 2, \\
3x_1 - 4x_2 + 3x_3 &amp;= 7, \\
4x_1 + 2x_2 - 5x_3 &amp;= 10,
\end{align*}\begin{align*}	
A_b &amp;= \begin{bmatrix}
2 &amp; -1 &amp; -1 &amp; : &amp; 2 …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 04 Sep 2024 03:11:42 +0000</pubDate>
        </item>
        <item>
            <title>Question 5, Exercise 2.6</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-6-p5</link>
            <description>Question 5, Exercise 2.6

Solutions of Question 5 of Exercise 2.6 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $x_{1}+x_{2}+2 x_{3}=8$$-x_{1}-2 x_{2}+3 x_{3}=1$$3 x_{1}-7 x_{2}+4 x_{3}=10$$A X=B$\begin{align*}
&amp;A = \begin{bmatrix}
1 &amp; 1 &amp; 2 \\
-1 &amp; -2 &amp; 3 \\
3 &amp; -7 &amp; 4
\end{bmatrix}, \quad
X = \begin{bmatrix}
x_1 \\
x_2 \\
x_3
\end{bmatrix}, \quad
B = \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 04 Sep 2024 03:12:33 +0000</pubDate>
        </item>
        <item>
            <title>Question 6, Exercise 2.6</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-6-p6</link>
            <description>Question 6, Exercise 2.6

Solutions of Question 6 of Exercise 2.6 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $5 x+3 y+z=6$$2 x+y+3 z=19$$x+2 y+4 z=25$\begin{align*}
A &amp;= \begin{bmatrix}
5 &amp; 3 &amp; 1 \\
2 &amp; 1 &amp; 3 \\
1 &amp; 2 &amp; 4
\end{bmatrix}, \quad
X = \begin{bmatrix}
x \\
y \\
z
\end{bmatrix}, \quad
B = \begin{bmatrix}
6 \\
19 \\
25
\end{bmatrix}
\end{alig…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 04 Sep 2024 03:13:00 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 and 8, Exercise 2.6</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-6-p7</link>
            <description>Question 7 and 8, Exercise 2.6

Solutions of Question 7 and 8 of Exercise 2.6 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $A=\left[\begin{array}{ccc}3 &amp; 2 &amp; 1 \\ 4 &amp; -1 &amp; 2 \\ 7 &amp; 3 &amp; -3\end{array}\right]$$A^{-1}$$3 x+4 y+7 z=14 ; 2 x-y+3 z=4 ; \quad x+2 y-3 z=0$\begin{align*}
A &amp;= \begin{bmatrix}
3 &amp; 2 &amp; 1 \\
4 &amp; -1 &amp; 2 \\
7 &amp; 3 &amp; -3
\end{bmatrix}\\
|…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 04 Sep 2024 03:13:32 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 and 10, Exercise 2.6</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/ex2-6-p8</link>
            <description>Question 9 and 10, Exercise 2.6

Solutions of Question 9 and 10 of Exercise 2.6 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $2 x-y+3 z=\alpha ; 3 x+y-5 z=\beta ;-5 x-5 y+21 z=\gamma$$\gamma \neq 2 \alpha-3 \beta$$2$$2$$3$$3$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 04 Sep 2024 03:13:56 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/re-ex-p1</link>
            <description>Question 1, Review Exercise

Solutions of Question 1 of Review Exercise of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $A$$m \times n$$B$$n \times p$$A B$$n \times p$$m \times p$$p \times m$$n \times n$$m \times p$$A$$1 \times n$$A^{t} A$$1 \times n$$n \times 1$$1 \times 1$$n \times n$$n \times n$$a_{i j}$$A$$a_{i j}=(-1)^{i+j} A_{i j}$$a_{i j}=(-1)^{i+j}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 25 Nov 2024 17:51:01 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 and 3, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/re-ex-p2</link>
            <description>Question 2 and 3, Review Exercise

Solutions of Question 2 and 3 of Review Exercise of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $A=\left[\begin{array}{ccc}1 &amp; 2 &amp; 0 \\ -3 &amp; 4 &amp; 9 \\ 2 &amp; 1 &amp; 6\end{array}\right]$$A_{13}, A_{23}$$A_{33}$$|A|$\begin{align*}
A&amp;=\left[\begin{array}{ccc}1 &amp; 2 &amp; 0 \\ -3 &amp; 4 &amp; 9 \\ 2 &amp; 1 &amp; 6\end{array}\right]\\
A_{13} &amp;= (-1)^{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 04 Sep 2024 03:15:23 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 and 5, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/re-ex-p3</link>
            <description>Question 4 and 5, Review Exercise

Solutions of Question 4 and 5 of Review Exercise of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\left|\begin{array}{ccc}a+1 &amp; l &amp; l \\ l &amp; a+1 &amp; l \\ l &amp; l &amp; a+1\end{array}\right|=(a+1+2 l)(a+1-l)^{2}$\begin{align*}
L.H.S &amp;= \left|\begin{array}{ccc}a+1 &amp; l &amp; l \\ l &amp; a+1 &amp; l \\ l &amp; l &amp; a+1\end{array}\right|\\
&amp;=\left|\b…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 04 Sep 2024 03:15:45 +0000</pubDate>
        </item>
        <item>
            <title>Review Exercise 2 (Solutions)</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit02/rev-ex</link>
            <description>Review Exercise 2 (Solutions)

The solutions of the Review Exercise 2 of book “Model Textbook of Mathematics for Class XI” published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan are given on this page. This exercise consists of the MCQs and question all topics included in this chapter.$A$$m \times n$$B$$n \times p$$A B$$n \times p$$m \times p$$p \times m$$n \times n$$A$$1 \times n$$A^{t} A$$1 \times n$$n \times 1$$1 \times 1$$n \times n$$a_{i j}$$A$$a_{i j}=(-…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 08 Feb 2026 16:57:09 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 and 2, Exercise 4.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-1-p1</link>
            <description>Question 1 and 2, Exercise 4.1

Solutions of Question 1 and 2 of Exercise 4.1 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $n$$a_{10}$$a_{15}$$$a_{n}=3 n+1$$$$a_{n}=3 n+1$$\begin{align*}
a_1 &amp;= 3(1) + 1 = 3 + 1 = 4\\
a_2 &amp;= 3(2) + 1 = 6 + 1 = 7\\
a_3 &amp;= 3(3) + 1 = 9 + 1 = 10\\
a_4 &amp;= 3(4) + 1 = 12 + 1 = 13\\
\end{align*}\begin{align*}
a_{10} &amp;= 3(10) + 1 = 30…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 14 Sep 2024 16:29:10 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 and 4, Exercise 4.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-1-p2</link>
            <description>Question 3 and 4, Exercise 4.1

Solutions of Question 3 and 4 of Exercise 4.1 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $n$$a_{10}$$a_{n}=\frac{n}{n+1}$$$a_n = \frac{n}{n+1}.$$\begin{align*}

a_1 &amp;= \frac{1}{1+1} = \frac{1}{2}\\
a_2 &amp;= \frac{2}{2+1} = \frac{2}{3}\\
a_3 &amp;= \frac{3}{3+1} = \frac{3}{4}\\
a_4 &amp;= \frac{4}{4+1} = \frac{4}{5}\\
\end{align*}\begin…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 14 Sep 2024 16:33:03 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 and 6, Exercise 4.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-1-p3</link>
            <description>Question 5 and 6, Exercise 4.1

Solutions of Question 5 and 6 of Exercise 4.1 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $n$$a_{10}$$a_{15}$$a_{n}=n^{2}-2 n$$$a_n = n^2 - 2n.$$\begin{align*}
a_1 &amp;= (1)^2 - 2(1) = 1 - 2 = -1\\
a_2 &amp;= (2)^2 - 2(2) = 4 - 4 = 0\\
a_3 &amp;= (3)^2 - 2(3) = 9 - 6 = 3\\
a_4 &amp;= (4)^2 - 2(4) = 16 - 8 = 8\\
\end{align*}\begin{align*}
a_{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 14 Sep 2024 16:37:26 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 and 8, Exercise 4.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-1-p4</link>
            <description>Question 7 and 8, Exercise 4.1

Solutions of Question 7 and 8 of Exercise 4.1 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $n$$a_{10}$$a_{15}$$a_{n}=\left(\frac{-1}{2}\right)^{n-1}$$$a_n = \left( \frac{-1}{2} \right)^{n-1}.$$\begin{align*}a_1 &amp;= \left( \frac{-1}{2} \right)^{1-1} = \left( \frac{-1}{2} \right)^0 = 1 \\
a_2 &amp;= \left( \frac{-1}{2} \right)^{2-1} =…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 14 Sep 2024 16:39:31 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 and 10, Exercise 4.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-1-p5</link>
            <description>Question 9 and 10, Exercise 4.1

Solutions of Question 9 and 10 of Exercise 4.1 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $n$$a_{10}$$a_{15}$$a_{n}=(-1)^{n}(n+3)$$n$$a_{10}$$a_{15}$$$a_{n}=(-1)^{n+1}(3 n-5).$$$$a_n = (-1)^{n+1}(3n - 5).$$\begin{align*}
a_1 &amp;= (-1)^{1+1}(3(1) - 5) = (1)(3 - 5) = -2 \\
a_2 &amp;= (-1)^{2+1}(3(2) - 5) = (-1)(6 - 5) = -1 \\
a_3 &amp;=…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 14 Sep 2024 16:42:36 +0000</pubDate>
        </item>
        <item>
            <title>Question 11 and 12, Exercise 4.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-1-p6</link>
            <description>Question 11 and 12, Exercise 4.1

Solutions of Question 11 and 12 of Exercise 4.1 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $a_{n}=4 n-3; a_8$$$a_n = 4n - 3.$$\begin{align*}
a_8 &amp;= 4(8) - 3 \\
&amp;= 32 - 3 \\
&amp;= 29
\end{align*}$a_8 = 29$$a_{n}=5 n+11 ; a_{9}$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 14 Sep 2024 16:45:13 +0000</pubDate>
        </item>
        <item>
            <title>Question 13 and 14, Exercise 4.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-1-p7</link>
            <description>Question 13 and 14, Exercise 4.1

Solutions of Question 13 and 14 of Exercise 4.1 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $a_{n}=(3 n+4)(2 n-5) ; a_{7}$$a_{n}=(-1)^{n-1}(3.4 n-17.3) ; a_{12}$$$a_n = (-1)^{n-1}(3.4n - 17.3).$$\begin{align*}
a_{12} &amp;= (-1)^{12-1}(3.4 \cdot 12 - 17.3) \\
&amp;= (-1)^{11}(40.8 - 17.3) \\
&amp;= (-1)^{11}(23.5) \\
&amp;= -23.5
\end{align…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 14 Sep 2024 16:46:57 +0000</pubDate>
        </item>
        <item>
            <title>Question 15 and 16, Exercise 4.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-1-p8</link>
            <description>Question 15 and 16, Exercise 4.1

Solutions of Question 15 and 16 of Exercise 4.1 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $a_{n}=4 n^{2}(11 n+31) ; a_{22}$$$a_n = 4n^2(11n + 31).$$\begin{align*}
a_{22} &amp;= 4 \cdot 22^2 \cdot (11 \cdot 22 + 31) \\
&amp;= 4 \cdot 484 \cdot (242 + 31) \\
&amp;= 4 \cdot 484 \cdot 273 \\
&amp;= 4 \cdot 132132 \\
&amp;= 528528
\end{align*}$a_{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 14 Sep 2024 16:48:53 +0000</pubDate>
        </item>
        <item>
            <title>Question 17 and 18, Exercise 4.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-1-p9</link>
            <description>Question 17 and 18, Exercise 4.1

Solutions of Question 17 and 18 of Exercise 4.1 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $a_{n}=\log 10^{n} ; a_{43}$$$a_n = \log 10^n.$$\begin{align*}
a_{43} &amp;= \log 10^{43} \\
&amp;= 43 \cdot \log 10 \\
&amp;= 43 \cdot 1 \\
&amp;= 43
\end{align*}$a_{43}= 43$$a_{n}=\ln e^{n} ; a_{67}$$$a_n = \ln e^n.$$\begin{align*}
a_{67} &amp;= \ln e^…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 14 Sep 2024 17:38:01 +0000</pubDate>
        </item>
        <item>
            <title>Question 19 and 20, Exercise 4.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-1-p10</link>
            <description>Question 19 and 20, Exercise 4.1

Solutions of Question 19 and 20 of Exercise 4.1 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $a_{n}$$1,3,5,7,9, \ldots$$$1, 3, 5, 7, 9, \ldots$$$a_1=1$$d=3-1=2$$$a_n = a_1 + (n - 1) d$$\begin{align*}
\implies a_n &amp;= 1 + (n - 1) \cdot 2\\
 &amp;= 1 + 2n - 2\\
&amp;= 2n - 1 \end{align*}$a_n = 2n - 1$$a_{n}$$3,9,27,81,243, \ldots$\begin…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 14 Sep 2024 17:59:38 +0000</pubDate>
        </item>
        <item>
            <title>Question 21 and 22, Exercise 4.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-1-p11</link>
            <description>Question 21 and 22, Exercise 4.1

Solutions of Question 21 and 22 of Exercise 4.1 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $a_{n}$$\sqrt{2}, \sqrt{4}, \sqrt{6}, \sqrt{8}, \sqrt{10}, \ldots$$$\sqrt{2}, \sqrt{4}, \sqrt{6}, \sqrt{8}, \sqrt{10}, \ldots$$\begin{align*}
&amp;a_1=\sqrt{2 \cdot 1}, \\
&amp;a_2=\sqrt{4}=\sqrt{2 \cdot 2} \\
&amp;a_3=\sqrt{6}=\sqrt{2 \cdot 3}\\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 14 Sep 2024 18:01:00 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 4.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-2-p1</link>
            <description>Question 1, Exercise 4.2

Solutions of Question 1 of Exercise 4.2 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $a_{1}=4, d=3$$a_1= 4$$d=3$$$a_n = a_1 + (n - 1)d.$$\begin{align*}
a_2&amp;=4+(2-1)3=4+3=7\\
a_3 &amp;= 4+ (3-1) 3 = 4 + 6 = 10\\
a_4&amp;=4+(4-1)3=4+9=13
\end{align*}$a_1=4$$a_2=7$$a_3=10$$a_4=13$$a_1=7$$d=5$$a_1= 7$$d=5$$$a_n = a_1 + (n - 1)d.$$\begin{align*}
…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 15 Sep 2024 12:26:08 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Exercise 4.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-2-p2</link>
            <description>Question 2, Exercise 4.2

Solutions of Question 2 of Exercise 4.2 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $5,9,13, \ldots$$$5, 9, 13, \ldots $$$a_1=5$$d=9-5=4$$$a_n=a_1+(n-1)d.$$\begin{align*}
a_4 &amp;=5+(4-1)(4)=5+12=17\\
a_5 &amp;=5+(5-1)(4)=5+16=21\\
a_6 &amp;=5+(6-1)(4)=5+20=25
\end{align*}$17$$21$$25$$11,14,17, \ldots$$$11, 14, 17, \ldots$$$a_1=11$$d=14-11=3$$…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 15 Sep 2024 12:29:31 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 and 4, Exercise 4.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-2-p3</link>
            <description>Question 3 and 4, Exercise 4.2

Solutions of Question 3 and 4 of Exercise 4.2 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $0.07,0.12,0.7, \ldots$$$0.07,0.12,0.7, \ldots$$$a_1 = 0.07$$d=0.05$$a_{11}=?$\begin{align*}
a_n&amp;=a_1+(n-1)d \\
\implies a_{11}&amp;= 0.07+(11-1)(0.05)\\
&amp;=0.07+(10)(0.05)\\
&amp;=0.57
\end{align*}$a_{11}=0.57.$$a_3 = 14$$a_9 = -1$$$a_n = a_1 + (…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 20 Sep 2024 16:59:34 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 and 6, Exercise 4.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-2-p4</link>
            <description>Question 5 and 6, Exercise 4.2

Solutions of Question 5 and 6 of Exercise 4.2 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $a_{17}=-40$$a_{28}=-73$$a_{1}$$d$$$a_n=a_1+(n-1)d$$\begin{align*}
&amp; a_{17} = -40 \\
\implies &amp;a_1 + 16d = -40 \quad \cdots (1)
\end{align*}\begin{align*}
&amp;a_{28}=-73\\
\implies &amp;a_1 + 27d = -73 \quad \cdots (2)
\end{align*}\begin{align*}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 20 Sep 2024 17:08:12 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 and 8, Exercise 4.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-2-p5</link>
            <description>Question 7 and 8, Exercise 4.2

Solutions of Question 7 and 8 of Exercise 4.2 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $-6,-2,2, \ldots$$70$$-6,-2,2, \ldots$$a_1=-6$$d=-2+6=4$$a_n=70$$n=?$$$a_n=a_1+(n-1)d.$$\begin{align*}
&amp;70=-6+(n-1)4\\
\implies &amp;70=-6+4n-4\\
\implies &amp;70=4n-10\\
\implies &amp;4n=80\\
\implies &amp; n=20
\end{align*}$a_{20}=70$$\dfrac{5}{2}, \df…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 20 Sep 2024 17:20:28 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 and 10, Exercise 4.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-2-p6</link>
            <description>Question 9 and 10, Exercise 4.2

Solutions of Question 9 and 10 of Exercise 4.2 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\dfrac{1}{a}, b, \dfrac{1}{c}$$\dfrac{a-c}{2 a c}$$\dfrac{1}{a}, b, \dfrac{1}{c}$\begin{align*}
d&amp;=b-\frac{1}{a}\cdots (i)\\
\end{align*}\begin{align*}
d&amp;=\frac{1}{c}-b \cdots (ii)
\end{align*}\begin{align*}
b-\frac{1}{a}&amp;=\frac{1}{c}-…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 20 Sep 2024 17:28:31 +0000</pubDate>
        </item>
        <item>
            <title>Question 11 and 12, Exercise 4.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-2-p7</link>
            <description>Question 11 and 12, Exercise 4.2

Solutions of Question 11 and 12 of Exercise 4.2 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $1000$$3000$$2$$5000$$3$$20$$$1000, 3000, 5000, \dots, \text{ upto 20 terms}.$$$a_1 = 1000$$d=3000-1000=2000$$S_20=?$$$S_n =\frac{n}{2}[2a_1+(n-1)d],$$\begin{align*}
S_{20} &amp;= \frac{20}{2}[2(1000)+(20-1)2000]\\
&amp;= 10 [2000+(19)2000] \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 20 Sep 2024 17:46:01 +0000</pubDate>
        </item>
        <item>
            <title>Question 13, Exercise 4.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-2-p8</link>
            <description>Question 13, Exercise 4.2

Solutions of Question 13 of Exercise 4.2 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $7$$17$$a=7$$b=17$\begin{align*}
\text{A.M.} &amp;= \frac{a + b}{2}\\
&amp;= \frac{7 + 17}{2} \\
&amp;= \frac{24}{2} = 12.
\end{align*}$12$$3+3 \sqrt{2}$$7-3 \sqrt{2}$$a=3+3\sqrt{2}$$b=7-3\sqrt{2}$\begin{align*}
\text{A.M.} &amp;= \frac{a + b}{2}\\
&amp;= \frac{(3 + 3…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 20 Sep 2024 18:05:05 +0000</pubDate>
        </item>
        <item>
            <title>Question 14 and 15, Exercise 4.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-2-p9</link>
            <description>Question 14 and 15, Exercise 4.2

Solutions of Question 14 and 15 of Exercise 4.2 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $b$$10$$b$$20$$a= b$$b=20$\begin{align*}
&amp;\text{A.M.} = \frac{a + b}{2} \\
\implies &amp; 10 = \frac{b + 20}{2} \\
\implies &amp; 20 = b + 20 \\
\implies &amp; b = 20 - 20 \\
\implies &amp; b = 0
\end{align*}$b = 0$$b$$25$$b$$20$$b$$10$$b$$-10$$x$$y$…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 20 Sep 2024 18:31:40 +0000</pubDate>
        </item>
        <item>
            <title>Question 16 and 17, Exercise 4.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-2-p10</link>
            <description>Question 16 and 17, Exercise 4.2

Solutions of Question 16 and 17 of Exercise 4.2 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $5$$17$$A_1$$A_2$$5$$17$$5$$A_1$$A_2$$17$$a_1=5$$a_4=17$$$a_n=a_1+(n-1)d.$$\begin{align*}
&amp;a_4 = a_1 + 3d \\
\implies &amp; 17=5+3d\\
\implies &amp; 3d=12\\
\implies &amp; \boxed{d=4}.\end{align*}\begin{align*}
A_1 &amp;= a_2= a_1+d \\
&amp;=5+4=9 \end{a…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 20 Sep 2024 18:45:04 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 and 2, Exercise 4.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-3-p1</link>
            <description>Question 1 and 2, Exercise 4.3

Solutions of Question 1 and 2 of Exercise 4.3 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $4+7+10+13+16+19+22+25$$4+7+10+13+16+19+22+25$$a_1=4$$d=7-4=3$$n=8$\begin{align}
S_n&amp;=\frac{n}{2}[2a_1+(n-1)d]\\
\implies S_8&amp;=\frac{8}{2}[2(4)+(8-1)(3)]\\
&amp;=4[8+7\times 3] = 116
\end{align}$a_{1}=2$$a_{n}=200$$n=100$$a_{1}=2$$a_{n}=200$$…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 14 Sep 2024 16:15:56 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 and 4, Exercise 4.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-3-p2</link>
            <description>Question 3 and 4, Exercise 4.3

Solutions of Question 3 and 4 of Exercise 4.3 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $a_{1}=5$$a_{n}=100$$n=200$$a_{1}=5$$a_{n}=100$$n=200$$a_{1}=5$$a_{n}=100$$n=200$$S_n$\begin{align}
S_n&amp;=\frac{n}{2}[a_1+a_n] \\
\implies S_{200}&amp;=\frac{200}{2}[5+100]\\
&amp;=10500.
\end{align}$S_{200}=10500$$a_{1}=4$$n=15$$d=3$$a_{1}=4$$n=1…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 14 Sep 2024 16:17:02 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 and 6, Exercise 4.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-3-p3</link>
            <description>Question 5 and 6, Exercise 4.3

Solutions of Question 5 and 6 of Exercise 4.3 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $a_{1}=50$$n=20$$d=-4$$a_{1}=50$$n=20$$d=-4$$a_{1}=50$$n=20$$d=-4$$S_n$\begin{align}
S_n&amp;=\frac{n}{2}[2a_1+(n-1)d] \\
\implies S_{20}&amp;=\frac{20}{2}[2(50)+(20-1)(-4)]\\
&amp;=10\times [100-76]\\
&amp;=240.
\end{align}$S_{20}=240$$-3+(-7)+(-11)+\cd…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 14 Sep 2024 16:17:27 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 and 8, Exercise 4.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-3-p4</link>
            <description>Question 7 and 8, Exercise 4.3

Solutions of Question 7 and 8 of Exercise 4.3 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $9+11+13+15+\cdots$$n=12$$a_1=9$$d=11-9=2$$n=12$$S_n$\begin{align}
S_n&amp;=\frac{n}{2}[2a_1+(n-1)d] \\
\implies S_{12}&amp;=\frac{12}{2}[2(9)+(12-1)(2)]\\
&amp;=6\times [18+22]\\
&amp;=240.
\end{align}$S_{12}=240$$2$$100$$2$$100$$$2+4+6+...+100 (50 \tex…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 14 Sep 2024 16:17:56 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 and 10, Exercise 4.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-3-p5</link>
            <description>Question 9 and 10, Exercise 4.3

Solutions of Question 9 and 10 of Exercise 4.3 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $1$$99$$1$$99$$$1+3+5+...+99 (50 \text{ terms}).$$$a_{1}=1$$n=50$$d=3-1=2$$S_n$\begin{align}
S_n&amp;=\frac{n}{2}[2a_1+(n-1)d] \\
\implies S_{50}&amp;=\frac{50}{2}[2(1)+(50-1)(2)]\\
&amp;=25\times [2+98]\\
&amp;=2500.
\end{align}$1$$99$$2500$$14$$523$$…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 14 Sep 2024 16:19:25 +0000</pubDate>
        </item>
        <item>
            <title>Question 11 and 12, Exercise 4.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-3-p6</link>
            <description>Question 11 and 12, Exercise 4.3

Solutions of Question 11 and 12 of Exercise 4.3 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $S_{\boldsymbol{n}}$$a_{1}=3$$a_{n}=-38$$n=8$$a_{1}=3$$a_{n}=-38$$n=8$\begin{align}
S_n&amp;=\frac{n}{2}[a_1+a_n] \\
\implies S_{8}&amp;=\frac{8}{2}[3-38]\\
&amp;=4\times[-35] \\
&amp;=-140.
\end{align}$S_{8}=-140$$S_n$$a_{1}=85$$n=21$$a_{n}=25$$a_{1…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 14 Sep 2024 16:19:47 +0000</pubDate>
        </item>
        <item>
            <title>Question 13 and 14, Exercise 4.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-3-p7</link>
            <description>Question 13 and 14, Exercise 4.3

Solutions of Question 13 and 14 of Exercise 4.3 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $S_s$$a_{1}=34$$n=9$$a_{n}=2$$a_{1}=34$$n=9$$a_{n}=2$\begin{align}
S_n&amp;=\frac{n}{2}[a_1+a_n] \\
\implies S_{9}&amp;=\frac{9}{2}[34+2]\\
&amp;=162.
\end{align}$S_{9}=162$$S_n$$a_{1}=5$$d=\frac{1}{2}$$n=13$$a_{1}=5$$d=\frac{1}{2}$$n=13$\begin{a…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 14 Sep 2024 16:23:14 +0000</pubDate>
        </item>
        <item>
            <title>Question 15 and 16, Exercise 4.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-3-p8</link>
            <description>Question 15 and 16, Exercise 4.3

Solutions of Question 15 and 16 of Exercise 4.3 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $S_n$$a_{1}=91$$d=-4$$a_{n}=15$$a_{1}=91$$d=-4$$a_{n}=15$$n=?$\begin{align} 
&amp; a_n=a_1+(n-1)d \\
\implies &amp; 15=91+(n-1)(-4) \\
\implies &amp; 15=91-4n+4 \\
\implies &amp; 4n=95-15 \\
\implies &amp;  4n = 80\\ \implies &amp; n = 20.
\end{align}\begin{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 14 Sep 2024 16:23:39 +0000</pubDate>
        </item>
        <item>
            <title>Question 17, 18 and 19, Exercise 4.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-3-p9</link>
            <description>Question 17, 18 and 19, Exercise 4.3

Solutions of Question 17, 18 and 19 of Exercise 4.3 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $6+12+18+\ldots+96$$$6+12+18+\ldots+96.$$$a_{1}=6$$d=12-6=6$$a_{n}=96$$n=?$\begin{align} 
&amp; a_n=a_1+(n-1)d \\
\implies &amp; 96=6+(n-1)(6) \\
\implies &amp; 96=6+6n-6 \\
\implies &amp; 6n=96 \\
\implies &amp;  n = 24.
\end{align}\begin{align}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 14 Sep 2024 16:23:56 +0000</pubDate>
        </item>
        <item>
            <title>Question 20, 21 and 22, Exercise 4.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-3-p10</link>
            <description>Question 20, 21 and 22, Exercise 4.3

Solutions of Question 20, 21 and 22 of Exercise 4.3 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $a_{1}=7$$a_{n}=139$$S_{n}=876$$a_{1}=7$$a_{n}=139$$S_{n}=876$$n$$d$\begin{align}
&amp;S_n=\frac{n}{2}[a_1+a_n]\\
\implies &amp; 876=\frac{n}{2}[7+139]\\
\implies &amp; 1752=146n\\
\implies &amp; n=\frac{1752}{146}=12.
\end{align}\begin{align…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 14 Sep 2024 16:24:21 +0000</pubDate>
        </item>
        <item>
            <title>Question 23 and 24, Exercise 4.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-3-p11</link>
            <description>Question 23 and 24, Exercise 4.3

Solutions of Question 23 and 24 of Exercise 4.3 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $$ 14+16+18+...+a_{25}.$$$a_1=14$$d=16-14=2$$n=25$$a_25$$S_25$\begin{align}
a_n&amp;=a_1+(n-1)d\\
\implies a_{25}&amp;= 14+(25-1)(2)\\
&amp;=62.
\end{align}\begin{align}
S_n&amp;=\frac{n}{2}[a_1+a_n]\\
\implies S_{25}&amp; =\frac{25}{2}[14+62]\\
&amp; =25 \t…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 14 Sep 2024 16:24:52 +0000</pubDate>
        </item>
        <item>
            <title>Question 25 and 26, Exercise 4.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-3-p12</link>
            <description>Question 25 and 26, Exercise 4.3

Solutions of Question 25 and 26 of Exercise 4.3 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $$ 6000+70,000+...+a_{20}.$$$a_1=6,000$$d=70,000-6,000=64,000$$n=20$$S_n$\begin{align}
S_n&amp;=\frac{n}{2}[2a_1+(n-1)d]\\
\implies S_{20}&amp; =\frac{20}{2}[2(6,000)+(20-1)(64,000)]\\
&amp; =10 \times [12,000+1,216,000]\\
&amp; =12,280,000.
\end{ali…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 14 Sep 2024 16:25:19 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 and 2, Exercise 4.4</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-4-p1</link>
            <description>Question 1 and 2, Exercise 4.4

Solutions of Question 1 and 2 of Exercise 4.4 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $5,20,100,500, \ldots$$5, 20, 100, 500, \ldots $\begin{align*}
\frac{20}{5} = 4\neq \frac{100}{20} = 5.\end{align*}$5, 20, 100, 500, \ldots $\begin{align*}
r_1&amp; =\frac{20}{5} = 4\\
r_2&amp;=\frac{100}{20} = 5\\
r_3&amp;=\frac{500}{100} = 5.
\end{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 22 Sep 2024 18:26:03 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 and 4, Exercise 4.4</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-4-p2</link>
            <description>Question 3 and 4, Exercise 4.4

Solutions of Question 3 and 4 of Exercise 4.4 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\frac{3}{2}, \frac{9}{4}, \frac{27}{8}, \frac{81}{16}, \ldots$\(\frac{3}{2}, \frac{9}{4}, \frac{27}{8}, \frac{81}{16}, \ldots\)\begin{align*}
r_1&amp;=\frac{9/4}{3/2} = \frac{9}{4} \times \frac{2}{3} = \frac{3}{2} \\
r_2&amp;=\frac{27/8}{9/4} = …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 22 Sep 2024 18:26:06 +0000</pubDate>
        </item>
        <item>
            <title>Question 5, 6 and 7, Exercise 4.4</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-4-p3</link>
            <description>Question 5, 6 and 7, Exercise 4.4

Solutions of Question 5, 6 and 7 of Exercise 4.4 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $a_{1}=3, r=-2$$a_{1}=3$$r=-2$$$a_{n}=a_{1} r^{n-1}.$$\begin{align*}
&amp; a_{2}=a_{1} r=(3)(-2)= -6 \\
&amp; a_{3}=a_{1} r^{2}=(3)(-2)^{2}=3 (4)= 12 \\
&amp; a_{4}=a_{1} r^{3}=(3)(-2)^{3}=3  (-8) = -24
\end{align*}$a_1=3$$a_2=-6$$a_3=12$$a_4=-…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 22 Sep 2024 18:26:06 +0000</pubDate>
        </item>
        <item>
            <title>Question 8 and 9, Exercise 4.4</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-4-p4</link>
            <description>Question 8 and 9, Exercise 4.4

Solutions of Question 8 and 9 of Exercise 4.4 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $$90,30,10 \ldots$$$a_1=90$$r=\dfrac{30}{90}=\dfrac{1}{3}$$$a_{n}=a_{1} r^{n-1}.$$\begin{align*}
&amp; a_{4}=a_{1} r^3=(90)\left(\dfrac{1}{3} \right)^3=90 \times\dfrac{1}{27}=\dfrac{10}{3}\\
&amp; a_{5}=a_{1} r^3=(90)\left(\dfrac{1}{4} \right)^4=…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 22 Sep 2024 18:26:06 +0000</pubDate>
        </item>
        <item>
            <title>Question 10 and 11, Exercise 4.4</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-4-p5</link>
            <description>Question 10 and 11, Exercise 4.4

Solutions of Question 10 and 11 of Exercise 4.4 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $$20,30,45 \ldots$$\(a_1=20\)\(r=\frac{30}{20}=\frac{3}{2}\)$$a_{n}=a_{1} r^{n-1}.$$\begin{align*}
&amp; a_{4}=a_{1} r^3=(20)\left(\frac{3}{2}\right)^3=20 \times \frac{27}{8} = \frac{540}{8} = 67.5 \\ 
&amp; a_{5}=a_{1} r^4=(20)\left(\frac{3}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 22 Sep 2024 18:26:07 +0000</pubDate>
        </item>
        <item>
            <title>Question 12 and 13, Exercise 4.4</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-4-p6</link>
            <description>Question 12 and 13, Exercise 4.4

Solutions of Question 12 and 13 of Exercise 4.4 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $$\frac{1}{27}, \frac{1}{9}, \frac{1}{3}, \ldots$$\(a_1=\frac{1}{27}\)\(r=\frac{\frac{1}{9}}{\frac{1}{27}}=3\)$a_{n}=a_{1} r^{n-1}.$\begin{align*}
&amp; a_{4}=a_{1} r^3=\left(\frac{1}{27}\right)(3)^3=\frac{1}{27} \times 27 = 1 \\ 
&amp; a_{5}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 22 Sep 2024 18:26:07 +0000</pubDate>
        </item>
        <item>
            <title>Question 14 and 15, Exercise 4.4</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-4-p7</link>
            <description>Question 14 and 15, Exercise 4.4

Solutions of Question 14 and 15 of Exercise 4.4 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $a_{1}=4, n=3, r=5$$a_{1}=4, n=3, r=5$$$a_{n}=a_{1} r^{n-1}.$$\begin{align*}
a_3&amp;= 4\times 5^2 \\
&amp;=4\times 25 = 100. 
\end{align*}$a_3=100$$a_{1}=2, n=5, r=2$$a_{1}=2$$n=5$$r=2$$a_{n}=a_{1} r^{n-1}.$\begin{align*}
a_5 &amp;= 2 \times 2^{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 22 Sep 2024 18:26:08 +0000</pubDate>
        </item>
        <item>
            <title>Question 16 and 17, Exercise 4.4</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-4-p8</link>
            <description>Question 16 and 17, Exercise 4.4

Solutions of Question 16 and 17 of Exercise 4.4 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $a_{1}=7, n=4, r=2$$a_{1}=7$$n=4$$r=2$$a_{n}=a_{1} r^{n-1}.$\begin{align*}
a_4 &amp;= 7 \times 2^{4-1} \\ 
&amp;= 7 \times 2^3 \\ 
&amp;= 7 \times 8 = 56.
\end{align*}$a_4=56$$a_{1}=243, n=5, r=-\frac{1}{3}$$a_{1}=243$$n=5$$r=-\frac{1}{3}$$a_{n}=…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 22 Sep 2024 18:26:08 +0000</pubDate>
        </item>
        <item>
            <title>Question 18 and 19, Exercise 4.4</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-4-p9</link>
            <description>Question 18 and 19, Exercise 4.4

Solutions of Question 18 and 19 of Exercise 4.4 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $a_{1}=32, n=6, r=-\frac{1}{2}$$a_{1}=32$$n=6$$r=-\frac{1}{2}$$a_{n}=a_{1} r^{n-1}.$\begin{align*}
a_6 &amp;= 32 \times \left(-\frac{1}{2}\right)^{6-1} \\ 
&amp;= 32 \times \left(-\frac{1}{2}\right)^{5} \\ 
&amp;= 32 \times \left(-\frac{1}{32}\ri…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 22 Sep 2024 18:26:09 +0000</pubDate>
        </item>
        <item>
            <title>Question 20 and 21, Exercise 4.4</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-4-p10</link>
            <description>Question 20 and 21, Exercise 4.4

Solutions of Question 20 and 21 of Exercise 4.4 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $$3 , \_\_\_ , \_\_\_ , \_\_\_ , 48$$$a_1=3$$a_5=48$$r$$$
a_n=ar^{n-1}.
$$\begin{align*}
&amp;a_5=a_1 r^4 \\
\implies &amp; 48=3r^4 \\
\implies &amp; r^4 = 16 \\
\implies &amp; r^4 = 2^4 \\
\implies &amp; r = 2.
\end{align*}\begin{align*}
&amp; a_2=a_1 r= (3…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 22 Sep 2024 18:26:02 +0000</pubDate>
        </item>
        <item>
            <title>Question 22 and 23, Exercise 4.4</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-4-p11</link>
            <description>Question 22 and 23, Exercise 4.4

Solutions of Question 22 and 23 of Exercise 4.4 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $$8 , \_\_\_, \_\_\_, \_\_\_, \_\_\_, \dfrac{1}{4}$$$a_1=8$$a_6=\frac{1}{4}$$r$$n$$a_n = a_1 r^{n-1}.$\begin{align*}
a_6 &amp;= a_1 r^5 \\
\implies \frac{1}{4} &amp;= 8 \cdot r^5 \\
\implies r^5 &amp;= \frac{1}{4 \cdot 8} \\
\implies r^5 &amp;= \frac…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 22 Sep 2024 18:26:03 +0000</pubDate>
        </item>
        <item>
            <title>Question 24 and 25, Exercise 4.4</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-4-p12</link>
            <description>Question 24 and 25, Exercise 4.4

Solutions of Question 24 and 25 of Exercise 4.4 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $$5 , \_\_\_, \_\_\_, \_\_\_, 80$$$a_1=5$$a_5=80$$r$$n$$$a_n = a_1 r^{n-1}.$$\begin{align*}
a_5 &amp;= a_1 r^4 \\
\implies 80 &amp;= 5 \cdot r^4 \\
\implies r^4 &amp;= \frac{80}{5} \\
\implies r^4 &amp;= 16 \\
\implies r &amp;= 2.
\end{align*}\begin{alig…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 22 Sep 2024 18:26:04 +0000</pubDate>
        </item>
        <item>
            <title>Question 26 and 27, Exercise 4.4</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-4-p13</link>
            <description>Question 26 and 27, Exercise 4.4

Solutions of Question 26 and 27 of Exercise 4.4 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $16\,\, ft$$6$$16\,\,ft$$a_1$$a_2$$a_3,...$$$a_1 = 16\times \dfrac{1}{4} = 4\,\, ft.$$$r=\dfrac{1}{4}$$a_6$$$a_{n}=a_{1} r^{n-1}.$$\begin{align*}
a_{6}&amp;=a_{1} r^5 \\
&amp;=(4)\left(\dfrac{1}{4} \right)^5 \\
&amp; = \dfrac{1}{256}
\end{align*}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 22 Sep 2024 18:26:04 +0000</pubDate>
        </item>
        <item>
            <title>Question 28 and 29, Exercise 4.4</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-4-p14</link>
            <description>Question 28 and 29, Exercise 4.4

Solutions of Question 28 and 29 of Exercise 4.4 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $=a_1= 1$$= a_2 = 2$$= a_3 = 2(2)=4$$= a_7$$$
1+2+4+...+a_7
$$$a_1=1$$r=2$$n=7$$$
S_n=\frac{a_1\left(1-r^n \right)}{1-r}, \quad r\neq 1.
$$\begin{align*}
S_6&amp;=\frac{(1)\left(1-2^7 \right)}{1-2} \\
&amp;=\frac{1-128}{-2}\\
&amp;=127
\end{align…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 22 Sep 2024 18:26:05 +0000</pubDate>
        </item>
        <item>
            <title>Question 30, Exercise 4.4</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-4-p15</link>
            <description>Question 30, Exercise 4.4

Solutions of Question 30 of Exercise 4.4 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $=a_1= 1$$=a_2= 3$$=a_3=3\times 3 = 9$$=a_4=3\times 9 = 27$$=a_5=3\times 27 = 81$$81$$a_1=1$$r=3$$a_5=?$$$a_n=a_1 r^{n-1}.$$\begin{align*}
a_5&amp;=a_1 r^4 \\
&amp;=(1)(3)^4 = 81
\end{align*}$$S_n=a_1+a_2+a_3+a_4+a_5.$$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 22 Sep 2024 18:26:05 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 and 2, Exercise 4.5</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-5-p1</link>
            <description>Question 1 and 2, Exercise 4.5

Solutions of Question 1 and 2 of Exercise 4.5 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $16+16+16+\ldots$$a_1=16$$r=\dfrac{16}{16}=1$$r\neq 1$\begin{align*}
&amp;16+16+16+\ldots \text{ to 11 terms}\\
=&amp;11(16) \\
=&amp; 176
\end{align*}$75+15+3+...$$75+15+3+...$$a_1= 75$$r = \frac{15}{75} = \frac{1}{5}$$n = 10$$n$$$ S_n = \frac{a_1 \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 22 Sep 2024 18:34:37 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 and 4, Exercise 4.5</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-5-p2</link>
            <description>Question 3 and 4, Exercise 4.5

Solutions of Question 3 and 4 of Exercise 4.5 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $a_{1}=5$$r=3$$n=12$$a_{1}=5$$r=3$$n=12$$n$\[
S_n = \frac{a_1 \left(1 - r^n\right)}{1 - r}, \quad r\neq 1.
\]\begin{align*}
S_{12} &amp;= \frac{5\left(1 - 3^{12}\right)}{1 - 3} \\
&amp;= \frac{5\left(1 - 531441\right)}{-2} \\
&amp;= \frac{5(-531440)}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 22 Sep 2024 18:26:10 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 and 6, Exercise 4.5</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-5-p3</link>
            <description>Question 5 and 6, Exercise 4.5

Solutions of Question 5 and 6 of Exercise 4.5 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $a_{1}=7, r=2, n=14$$a_1 = 7$$r = 2$$n = 14$$n$$$S_n = \frac{a_1 \left(1 - r^n\right)}{1 - r}, \quad r \neq 1.$$\begin{align*}
S_{14} &amp;= \frac{7 \left(1 - 2^{14}\right)}{1 - 2} \\
&amp;= \frac{7 \left(1 - 16384\right)}{-1} \\
&amp;= \frac{7 \time…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 22 Sep 2024 18:26:10 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 and 8, Exercise 4.5</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-5-p4</link>
            <description>Question 7 and 8, Exercise 4.5

Solutions of Question 7 and 8 of Exercise 4.5 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $a_{1}=16, r=-\frac{1}{2}, n=10$$a_1 = 16$$r = -\frac{1}{2}$$n = 10$$n$$$S_n = \frac{a_1 \left(1 - r^n\right)}{1 - r}, \quad r \neq 1.$$\begin{align*}
S_{10} &amp;= \frac{16 \left(1 - \left(-\frac{1}{2}\right)^{10}\right)}{1 - \left(-\frac{1}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 22 Sep 2024 18:26:11 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 and 10, Exercise 4.5</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-5-p5</link>
            <description>Question 9 and 10, Exercise 4.5

Solutions of Question 9 and 10 of Exercise 4.5 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $a_{1}=343, a_{4}=-1, r=-\frac{1}{7}$$a_{1}=343$$a_{4}=-1$$r=-\frac{1}{7}$$S_n$$$ S_n =\frac{a_1-a_n r}{1-r}, \quad r\neq 1.$$\begin{align*}
S_4 &amp; =\frac{343-(-1)\left(-\frac{1}{7}\right)}{1+\frac{1}{7}} \\
&amp;=\frac{\frac{2400}{7}}{\frac…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 22 Sep 2024 18:26:11 +0000</pubDate>
        </item>
        <item>
            <title>Question 11, 12 and 13, Exercise 4.5</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-5-p6</link>
            <description>Question 11, 12 and 13, Exercise 4.5

Solutions of Question 11, 12 and 13 of Exercise 4.5 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $a_{1}$$S_{n}=244, r=-3, n=5$$S_{n}=244$$r=-3$$n=5$$$ S_n =\frac{a_1(1-r^n)}{1-r}, \quad r\neq 1.$$\begin{align*}
&amp; 244=\frac{a_1(1-(-3)^5)}{1-(-3)} \\
\implies &amp; 244=\frac{a_1(1+243)}{4} \\
\implies &amp; 976=244a_1\\
\implies &amp; …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 22 Sep 2024 18:26:12 +0000</pubDate>
        </item>
        <item>
            <title>Question 14, Exercise 4.5</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-5-p7</link>
            <description>Question 14, Exercise 4.5

Solutions of Question 14 of Exercise 4.5 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $0.444...$$$0.444... = 0.4+0.04+0.004+...$$$a_1=0.4$$r=\frac{0.04}{0.4}=0.1$$|r|=0.1 &lt; 1$\begin{align*}
S-\infty &amp; = \frac{a_1}{1-r} \\
&amp; = \frac{0.4}{1.0.1} = \frac{0.4}{0.9} \\
&amp; = \frac{4}{9}.
\end{align*}$S_{\infty} =\dfrac{4}{9}$$9.99999 ...$$…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 22 Sep 2024 18:26:12 +0000</pubDate>
        </item>
        <item>
            <title>Question 15, Exercise 4.5</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-5-p8</link>
            <description>Question 15, Exercise 4.5

Solutions of Question 15 of Exercise 4.5 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $30 ft$$\frac{2}{5}$$= 30 ft$$= 30 \times \frac{2}{5} = 12 ft$$= 12 \times \frac{2}{5} = \frac{24}{5} ft$$= \frac{24}{5} \times \frac{2}{5} = \frac{48}{25} ft$$D$$$D=30+2\left(12+\frac{24}{5}+\frac{24}{5}+... \right)$$$$
12+\frac{24}{5}+\frac{24}{5…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 22 Sep 2024 18:26:13 +0000</pubDate>
        </item>
        <item>
            <title>Question 16, Exercise 4.5</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-5-p9</link>
            <description>Question 16, Exercise 4.5

Solutions of Question 16 of Exercise 4.5 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $80 ft$$90\%$$a_1$$a_1 r$$a_1 r^2$$=a_1= 80 ft$$r=90% = \frac{90}{100} =0.9$$A$\begin{align}
A &amp;= a_1+a_1r+a_1r^2+... \\
&amp; = \frac{a_1}{1-r} \\
&amp; = \frac{80}{1-0.9}\\
&amp;= 800
\end{align}$800 ft$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 22 Sep 2024 18:42:06 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 and 2, Exercise 4.6</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-6-p1</link>
            <description>Question 1 and 2, Exercise 4.6

Solutions of Question 1 and 2 of Exercise 4.6 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\frac{1}{9}, \frac{1}{12}, \frac{1}{15}, \cdots \quad 7$$$\frac{1}{9}, \frac{1}{12}, \frac{1}{15}, \cdots \text{ is in H.P.}$$$$9, 12, 15, ... \text{ is in A.P.}$$$a_1=9$$d=12-9=3$$a_7=?$$$
a_n=a_1+(n-1)d.
$$\begin{align*}
a_7&amp;=9+(6)(3) …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 24 Sep 2024 18:04:32 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 &amp; 4, Exercise 4.6</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-6-p2</link>
            <description>Question 3 &amp; 4, Exercise 4.6

Solutions of Question 3 &amp; 4 of Exercise 4.6 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\frac{1}{18}, \frac{1}{13}, \frac{1}{8}, \ldots \quad 20$\begin{align*}
&amp;\frac{1}{18}, \frac{1}{13}, \frac{1}{8}, \ldots \quad \text{ is in H.P.} \\
&amp;18, 13, 8, \ldots \quad \text{ is in A.P.}
\end{align*}$a_1 = 18$$d = 13 - 18 = -5$$a_{20}.…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 24 Sep 2024 18:04:55 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 &amp; 6, Exercise 4.6</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-6-p3</link>
            <description>Question 5 &amp; 6, Exercise 4.6

Solutions of Question 5 &amp; 6 of Exercise 4.6 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\dfrac{1}{27}, \dfrac{1}{20}, \dfrac{1}{13}, \ldots \quad$\begin{align*}
&amp;\frac{1}{27}, \frac{1}{20}, \frac{1}{13}, \ldots \quad \text{ is in H.P.} \\
&amp;27, 20, 13, \ldots \quad \text{ is in A.P.}
\end{align*}$a_1 = 27$$d = 20 - 27 = -7$$a_n=…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 24 Sep 2024 18:08:03 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 &amp; 8, Exercise 4.6</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-6-p4</link>
            <description>Question 7 &amp; 8, Exercise 4.6

Solutions of Question 7 &amp; 8 of Exercise 4.6 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\frac{1}{4}, \frac{1}{7}, \frac{1}{10}, \frac{1}{13}, \ldots$$ \frac{1}{4}, \frac{1}{7}, \frac{1}{10}, \frac{1}{13}, \ldots $$ a_1 = \frac{1}{4} $$d = \frac{1}{7} - \frac{1}{4} = -\frac{3}{28},$$ n = 14$$$a_n = a_1 + (n-1)d.$$\begin{align*}
…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 24 Sep 2024 18:07:44 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 &amp; 10, Exercise 4.6</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-6-p5</link>
            <description>Question 9 &amp; 10, Exercise 4.6

Solutions of Question 9 &amp; 10 of Exercise 4.6 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\frac{1}{7}, \frac{1}{6},-1,-\frac{1}{3}, \ldots$$$\frac{1}{7}, \frac{1}{6}, -1, -\frac{1}{3}, \ldots \text{ is in H.P.}$$$$7, 6, -1, -3, \ldots \text{ is in A.P.}$$$a_1 = 7$$d = 6 - 7 = -1$$a_8=?$$$
a_n = a_1 + (n-1)d.
$$\begin{align*}
a_…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 24 Sep 2024 18:08:26 +0000</pubDate>
        </item>
        <item>
            <title>Question 11, Exercise 4.6</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-6-p6</link>
            <description>Question 11, Exercise 4.6

Solutions of Question 11 of Exercise 4.6 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\dfrac{2}{3}$$\dfrac{4}{7}$$a=\dfrac{2}{3}$$b=\dfrac{4}{7}$\begin{align*}
\text{H.M.}&amp;=\frac{2ab}{a+b} \\
&amp;=\frac{2\times\frac{2}{3}\times\frac{4}{7}}{\frac{2}{3}+\frac{4}{7}} \\
&amp;=\frac{16/21}{26/21} \\
&amp;=\frac{8}{13} \\
\end{align*}$\dfrac{8}{13…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 24 Sep 2024 18:09:11 +0000</pubDate>
        </item>
        <item>
            <title>Question 12, Exercise 4.6</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-6-p7</link>
            <description>Question 12, Exercise 4.6

Solutions of Question 12 of Exercise 4.6 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\dfrac{1}{3}$$\dfrac{1}{11}$$H_1, H_2, H_3, H_4$$H.Ms$$\dfrac{1}{3}$$\dfrac{1}{11}$$$\dfrac{1}{3},H_1, H_2, H_3, H_4, \dfrac{1}{11} \text{ are in H.P.}$$$$\quad 3,\dfrac{1}{H_1},\dfrac{1}{H_2}, \dfrac{1}{H_3}, \dfrac{1}{H_4},11 \text{ are in A.P.}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 24 Sep 2024 18:09:33 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 and 2, Exercise 4.7</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-7-p1</link>
            <description>Question 1 and 2, Exercise 4.7

Solutions of Question 1 and 2 of Exercise 4.7 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\sum_{k=1}^{5} \frac{1}{2 k}$\begin{align*}
\sum_{k=1}^{5} \frac{1}{2k} &amp;= \frac{1}{2(1)} + \frac{1}{2(2)} + \frac{1}{2(3)} + \frac{1}{2(4)} + \frac{1}{2(5)}\\
&amp;= \frac{1}{2} + \frac{1}{4} + \frac{1}{6} + \frac{1}{8} + \frac{1}{10}\\
&amp;= …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 04 Oct 2024 19:06:32 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 and 4, Exercise 4.7</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-7-p2</link>
            <description>Question 3 and 4, Exercise 4.7

Solutions of Question 3 and 4 of Exercise 4.7 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\sum_{k=0}^{5} 2^{k}$\begin{align*}
\sum_{k=0}^{5} 2^{k} &amp;= 2^0 + 2^1 + 2^2 + 2^3 + 2^4 + 2^5 \\
&amp;= 1 + 2 + 4 + 8 + 16 + 32 \\
&amp;= 63
\end{align*}$\sum_{k=0}^{9} \pi k$\begin{align*}
\sum_{k=0}^{9} \pi k &amp;= \pi(0) + \pi(1) + \pi(2) + \pi(…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 04 Oct 2024 19:06:38 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 and 6, Exercise 4.7</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-7-p3</link>
            <description>Question 5 and 6, Exercise 4.7

Solutions of Question 5 and 6 of Exercise 4.7 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\sum_{k=1}^{8} \frac{k}{k+1}$\begin{align*}
\sum_{k=1}^{8} \frac{k}{k+1} &amp;= \frac{1}{2} + \frac{2}{3} + \frac{3}{4} + \frac{4}{5} + \frac{5}{6}\\
&amp;+ \frac{6}{7} + \frac{7}{8} + \frac{8}{9} \\
&amp;= 0.5 + 0.6667 + 0.75 + 0.8 + 0.8333\\
&amp;+ 0.…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 04 Oct 2024 19:06:39 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 and 8, Exercise 4.7</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-7-p4</link>
            <description>Question 7 and 8, Exercise 4.7

Solutions of Question 7 and 8 of Exercise 4.7 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\sum_{k=0}^{5}\left(k^{2}-2 k+3\right)$\begin{align*}
\sum_{k=0}^{5} (k^{2} - 2k + 3) &amp;= (0^{2} - 2(0) + 3) + (1^{2} - 2(1) + 3) + (2^{2} - 2 (2) + 3) \\
&amp;+ (3^{2} - 2 (3) + 3) + (4^{2} - 2 (4) + 3) + (5^{2} - 2 (5) + 3) \\
&amp;= (0 - 0 + 3…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 04 Oct 2024 19:06:39 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 and 10, Exercise 4.7</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-7-p5</link>
            <description>Question 9 and 10, Exercise 4.7

Solutions of Question 9 and 10 of Exercise 4.7 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\frac{1}{2}+\frac{2}{3}+\frac{3}{4}+\frac{4}{5}+\frac{5}{6}+\dots$$$
\frac{1}{2} + \frac{2}{3} + \frac{3}{4} + \frac{4}{5} + \frac{5}{6} +... = \sum_{k=1}^{\infty}\frac{k}{k+1}
$$$3+6+9+12+15$$$3+6+9+12+15=\sum_{k=1}^{5}3k$$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 04 Oct 2024 19:06:40 +0000</pubDate>
        </item>
        <item>
            <title>Question 11, 12 and 13, Exercise 4.7</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-7-p6</link>
            <description>Question 11, 12 and 13, Exercise 4.7

Solutions of Question 11, 12 and 13 of Exercise 4.7 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $-2+4-8+16-32+64$$$
-2 + 4 - 8 + 16 - 32 + 64 = \sum_{k=1}^{6} (-1)^k 2^k
$$$\frac{1}{1 \cdot 2}+\frac{1}{2 \cdot 3}+\frac{1}{3 \cdot 4}+\frac{1}{4 \cdot 5}+$$$
\frac{1}{1 \cdot 2} + \frac{1}{2 \cdot 3} + \frac{1}{3 \cdot 4} +…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 04 Oct 2024 19:06:40 +0000</pubDate>
        </item>
        <item>
            <title>Question 14, 15 and 16, Exercise 4.7</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-7-p7</link>
            <description>Question 14, 15 and 16, Exercise 4.7

Solutions of Question 14, 15 and 16 of Exercise 4.7 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $n$$n$$n+1$$T_n$$n$$$
T_{n} = n+1.
$$\begin{align*}\sum_{n=1}^{\infty} T_{n} &amp;= \sum_{n=1}^{\infty} (n+1)\\
&amp; = \sum_{n=1}^{\infty} n + \sum_{n=1}^{\infty} 1 \\
&amp; = \frac{n(n+1)}{2} + n \\
&amp; = \frac{n(n+1)}{2} + \frac{2n}{2} \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 04 Oct 2024 19:06:41 +0000</pubDate>
        </item>
        <item>
            <title>Question 17 and 18, Exercise 4.7</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-7-p8</link>
            <description>Question 17 and 18, Exercise 4.7

Solutions of Question 17 and 18 of Exercise 4.7 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $n$$2^{2}+5^{2}+8^{2}+\ldots$$2+5+8+\ldots$$a_k=2+(k-1)(3)=2+3k-3=3k-1$$T_k$$k$\begin{align*}T_k&amp;=(3k-1)^2 \\
&amp;=9k^2-6k+1. \end{align*}\begin{align*}\sum_{k=1}^{n} T_{k} &amp;= \sum_{k=1}^{n} (9k^{2} - 6k + 1)\\
&amp; = 9\sum_{k=1}^{n} k^{2} …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 04 Oct 2024 19:06:41 +0000</pubDate>
        </item>
        <item>
            <title>Question 19 and 20, Exercise 4.7</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-7-p9</link>
            <description>Question 19 and 20, Exercise 4.7

Solutions of Question 19 and 20 of Exercise 4.7 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $n$$1^{3}+3^{3}+5^{3}+$$1+3+5+\ldots$$a_k=1+(k-1)(2)=1+2k-2=2k-1$$T_k$$k$\begin{align*}T_k&amp;=(2k-1)^3 \\
&amp;=(2k)^3+3(2k)^2(-1)+3(2k)(-1)^2+(-1)^3 \\
&amp;=8k^3-12k^2+6k+1
\end{align*}\begin{align*}\sum_{k=1}^{n} T_{k} &amp;= \sum_{k=1}^{n} (8k^…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 04 Oct 2024 19:06:43 +0000</pubDate>
        </item>
        <item>
            <title>Question 19 and 20, Exercise 4.7</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-7-p10</link>
            <description>Question 19 and 20, Exercise 4.7

Solutions of Question 19 and 20 of Exercise 4.7 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $n$$1^{3}+3^{3}+5^{3}+$$1+3+5+\ldots$$a_k=1+(k-1)(2)=1+2k-2=2k-1$$T_k$$k$\begin{align*}T_k&amp;=(2k-1) \\
&amp;=9k^2-6k+1. \end{align*}\begin{align*}\sum_{k=1}^{n} T_{k} &amp;= \sum_{k=1}^{n} (2k - 1)\\
&amp; = 2 \sum_{k=1}^{n} k - \sum_{k=1}^{n} 1 \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 04 Oct 2024 19:06:32 +0000</pubDate>
        </item>
        <item>
            <title>Question 21 and 22, Exercise 4.7</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-7-p11</link>
            <description>Question 21 and 22, Exercise 4.7

Solutions of Question 21 and 22 of Exercise 4.7 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $n$$1 \times 4+2 \times 7+3 \times 10+\cdots$$4+7+10+\ldots$$a_k=4+(k-1)(3)=4+3k-3=3k+1$$1+2+3+...$$k$$k(3k+1)$$T_k$$k$\begin{align*}T_k&amp;=k(3k+1) \\
&amp;=3k^2+k. \end{align*}\begin{align*}\sum_{k=1}^{n} T_{k} &amp;= \sum_{k=1}^{n} (3k^2 +k)\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 04 Oct 2024 19:06:33 +0000</pubDate>
        </item>
        <item>
            <title>Question 23 and 24, Exercise 4.7</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-7-p12</link>
            <description>Question 23 and 24, Exercise 4.7

Solutions of Question 23 and 24 of Exercise 4.7 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $n$$$1+2 \times 2+3 \times 2^{2}+4 \times 2^{3}+\ldots.$$$$1+2 \times 2+3 \times 2^{2}+4 \times 2^{3}+\ldots$$$$
1\times 1+2 \times 2+3 \times 2^{2}+4 \times 2^{3}+\ldots
$$$1,2,3,4,\ldots$$a=1$$d=1$$1, 2, 2^2, 2^3, \ldots$$r=\frac{2}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 04 Oct 2024 19:06:34 +0000</pubDate>
        </item>
        <item>
            <title>Question 25 and 26, Exercise 4.7</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-7-p13</link>
            <description>Question 25 and 26, Exercise 4.7

Solutions of Question 25 and 26 of Exercise 4.7 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $n$$1+\frac{4}{7}+\frac{7}{7^{2}}+\frac{10}{7^{3}}+\ldots$\[
1 + \frac{4}{7} + \frac{7}{7^2} + \frac{10}{7^3} + \ldots
\]\(1, 4, 7, 10, \ldots\)\(a = 1\)\(d = 3\)\(1, \frac{1}{7}, \frac{1}{7^2}, \frac{1}{7^3}, \ldots\)\(1\)\(r = \frac…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 04 Oct 2024 19:06:36 +0000</pubDate>
        </item>
        <item>
            <title>Question 27 and 28, Exercise 4.7</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-7-p14</link>
            <description>Question 27 and 28, Exercise 4.7

Solutions of Question 27 and 28 of Exercise 4.7 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $$5+\frac{7}{3}+\frac{9}{9}+\frac{11}{27}+\ldots$$$$5+\frac{7}{3}+\frac{9}{9}+\frac{11}{27}+\ldots$$$$
5\times 1+7\times\frac{1}{3}+9\times\frac{1}{9}+11\times\frac{1}{27}+\ldots
$$$5,7,9,11,4,\ldots$$a=5$$d=7-5=2$$1, \dfrac{1}{3}, \d…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 04 Oct 2024 19:06:36 +0000</pubDate>
        </item>
        <item>
            <title>Question 29 and 30, Exercise 4.7</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-7-p15</link>
            <description>Question 29 and 30, Exercise 4.7

Solutions of Question 29 and 30 of Exercise 4.7 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $$1+4 x+7 x^{2}+10 x^{3}+\ldots$$\[
1 + 4x + 7x^2 + 10x^3 + \ldots
\]\[
1 \times 1 + 4 \times x + 7 \times x^2 + 10 \times x^3 + \ldots
\]\(1, 4, 7, 10, \ldots\)\(a = 1\)\(d = 4 - 1 = 3\)\(1, x, x^2, x^3, \ldots\)\(1\)\(r = x\)\[
S_{\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 04 Oct 2024 19:06:37 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 and 2, Exercise 4.8</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-8-p1</link>
            <description>Question 1 and 2, Exercise 4.8

Solutions of Question 1 and 2 of Exercise 4.8 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $3+7+13+21+\ldots$$n$$$ S_{n}=3+7+13+21+31+\ldots +T_{n} $$$$ S_{n}=3+7+13+21+\ldots +T_{n-1}+T_{n}.$$\begin{align*}
S_{n}-S_{n}&amp; =3+7+13+21+31+\ldots +T_{n}  \\
&amp; -\left(3+7+13+21+\ldots +T_{n-1}+T_{n}\right)
\end{align*}\begin{align*}
\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 06 Oct 2024 17:46:32 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 and 4, Exercise 4.8</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-8-p2</link>
            <description>Question 3 and 4, Exercise 4.8

Solutions of Question 3 and 4 of Exercise 4.8 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $1+4+13+40+121+ \ldots$$n$$$ S_{n}=1+4+13+40+121+\ldots +T_{n} $$$$ S_{n}=1+4+13+40+\ldots +T_{n-1}+T_{n}. $$\begin{align*}
	S_{n}-S_{n}&amp; =1+4+13+40+121+\ldots +T_{n}  \\
	&amp; -\left(1+4+13+40+\ldots +T_{n-1}+T_{n}\right)
\end{align*}\begin…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 06 Oct 2024 17:46:48 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 and 6, Exercise 4.8</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-8-p3</link>
            <description>Question 5 and 6, Exercise 4.8

Solutions of Question 5 and 6 of Exercise 4.8 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $3+4+6+10+18+34+66+\dots$$n$$$ S_{n}=3+4+6+10+18+\ldots +T_{n} $$$$ S_{n}=3+4+6+10+\ldots +T_{n-1}+T_{n}. $$\begin{align*}
S_{n}-S_{n}&amp; =3+4+6+10+18+\ldots +T_{n}  \\
&amp; -\left(3+4+6+10+\ldots +T_{n-1}+T_{n}\right)
\end{align*}\begin{align…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 06 Oct 2024 17:47:09 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 and 8, Exercise 4.8</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-8-p4</link>
            <description>Question 7 and 8, Exercise 4.8

Solutions of Question 7 and 8 of Exercise 4.8 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $n$$$\frac{1}{1 \times 4}+\frac{1}{4 \times 7}+\frac{1}{7 \times 10}+\ldots$$$$\frac{1}{1 \times 4}+\frac{1}{4 \times 7}+\frac{1}{7 \times 10}+\dots$$$T_k$\begin{align*}
T_k &amp;=\frac{1}{(3k-2)(3k+1)}.
\end{align*}\begin{align*}
\frac{1}{(3…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 06 Oct 2024 17:47:35 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 and 10, Exercise 4.8</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-8-p5</link>
            <description>Question 9 and 10, Exercise 4.8

Solutions of Question 9 and 10 of Exercise 4.8 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $$\frac{1}{1 \cdot 3}+\frac{1}{2 \cdot 5}+\frac{1}{3 \cdot 7}+\ldots \ldots \text{ up to } \infty$$$\sum_{k=3}^{n} \dfrac{1}{(k+1)(k+2)}$\begin{align*}
T_k &amp;= \frac{1}{(k+1)(k+2)}.
\end{align*}\begin{align*}
\frac{1}{(k+1)(k+2)} = \frac…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 06 Oct 2024 17:48:05 +0000</pubDate>
        </item>
        <item>
            <title>Question 11 and 12, Exercise 4.8</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-8-p6</link>
            <description>Question 11 and 12, Exercise 4.8

Solutions of Question 11 and 12 of Exercise 4.8 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\sum_{k=1}^{n} \frac{1}{k(k+2)}$$T_k$$k$\begin{align*}
T_k &amp;= \frac{1}{k(k+2)}.
\end{align*}\begin{align*}
\frac{1}{k(k+2)} = \frac{A}{k} + \frac{B}{k+2} \ldots (1)
\end{align*}$k(k+2)$\begin{align*}
	1 = A(k+2) + Bk \ldots (2)
\end{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 06 Oct 2024 17:48:33 +0000</pubDate>
        </item>
        <item>
            <title>Question 13, 14 and 15, Exercise 4.8</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit04/ex4-8-p7</link>
            <description>Question 13, 14 and 15, Exercise 4.8

Solutions of Question 13, 14 and 15 of Exercise 4.8 of Unit 04: Sequence and Series. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\frac{1}{5 \cdot 11}+\frac{1}{7 \cdot 13}+\frac{1}{9 \cdot 15}+\ldots \ldots$$n$$T_k$$k$\begin{align*}
T_k &amp;= \frac{1}{(2k+3)(2k+9)}.
\end{align*}\begin{align*}
\frac{1}{(2k+3)(2k+9)} = \frac{A}{2k+3} + \frac{B}{2k+9} \ldots …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 06 Oct 2024 17:49:14 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 5.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit05/ex5-1-p1</link>
            <description>Question 1, Exercise 5.1

Solutions of Question 1 of Exercise 5.1 of Unit 05: Polynomials. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 1(i)
$2 x^{3}+3 x^{2}-4 x+1$$x+2$$p(x)=2 x^{3}+3 x^{2}-4 x+1$$x-c=x+2 \implies c=-2$\begin{align*}
\text{Remainder} &amp; = p(c) = p(-2) \\
&amp; = 2(-2)^{3}+3 (-2)^{2}-4 (-2)+1 \\
&amp; = -16+12+8+1 \\
&amp;= 5.
\end{align*}$x^{4}+2 x^{3}-x^{2}+2 x+3$$x-2$\( p(x…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 10 Oct 2024 09:44:24 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 and 3, Exercise 5.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit05/ex5-1-p2</link>
            <description>Question 2 and 3, Exercise 5.1

Solutions of Question 2 and 3 of Exercise 5.1 of Unit 05: Polynomials. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $x-3$$x^{3}-2 x^{2}-5 x+6$$p(x)=x^{3}-2 x^{2}-5 x+6$$x-c=x-3$$\implies c=3$$x-3$$p(x)$$p(3)=0$\begin{align*}
p(3)&amp;=3^3-2(3)^2-5(3)+6 \\
&amp; = 27-18-15+6 \\
&amp; = 0.
\end{align*}$x-3$$p(x)$$x-3$$x^{3}-2 x^{2}-5 x+1$$p(x)=x^{3}-2 x^{2}-5 x+1$$x-c=x-3$$…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 10 Oct 2024 09:44:46 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 and 5, Exercise 5.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit05/ex5-1-p3</link>
            <description>Question 4 and 5, Exercise 5.1

Solutions of Question 4 and 5 of Exercise 5.1 of Unit 05: Polynomials. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $4 y^{3}-4 y^{2}+10+2 y$$4 y^{2}-8 y+10$$q$$x^{3}+q x^{2}-7 x+6$$(x+1)$$p(x)=x^{3}+q x^{2}-7 x+6$$x-c=x+1$$\implies c=-1$$x+1$$p(x)$$p(-1)=0$\begin{align*}
&amp;(-1)^3+q(-1)^2-7(-1)+6=0 \\
-&amp;1+q+7+6=0\\
&amp;q+12=0\\
&amp;q=-12
\end{align*}</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 10 Oct 2024 09:45:10 +0000</pubDate>
        </item>
        <item>
            <title>Question 6 and 7, Exercise 5.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit05/ex5-1-p4</link>
            <description>Question 6 and 7, Exercise 5.1

Solutions of Question 6 and 7 of Exercise 5.1 of Unit 05: Polynomials. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $m$$2 x^{3}+3 x^{2}-3 x-m$$x-2$$p(x)=2 x^{3}+3 x^{2}-3 x-m$$x-c=x-2$$\implies c=2$\begin{align*}
\text{Remainder} &amp; = p(c) = p(2) \\
&amp; = 2(2)^{3} + 3(2)^{2} - 3(2) - m \\
&amp; = 2(8) + 3(4) - 3(2) - m \\
&amp; = 16 + 12 - 6 - m \\
&amp; = 22 - m.
\end{align…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 10 Oct 2024 09:45:38 +0000</pubDate>
        </item>
        <item>
            <title>Question 8 and 9, Exercise 5.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit05/ex5-1-p5</link>
            <description>Question 8 and 9, Exercise 5.1

Solutions of Question 8 and 9 of Exercise 5.1 of Unit 05: Polynomials. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $2 x^{3}+3 x^{2}-11 x-6$$p(x)=2x^3+3x^2-11x-6$\begin{align}
p(2) &amp;= 2(2)^3+3(2)^2-11(2)-6 \\
&amp;=16+12-22-6 = 0 \end{align}$p(x)$\begin{align}
\begin{array}{r|rrrr}
2 &amp; 2 &amp; 3 &amp; -11 &amp; -6 \\
&amp; \downarrow  &amp;  4 &amp; 14 &amp; 6 \\
\hline
&amp; 2 &amp; 7 &amp; 3 &amp;  0 \\
\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 10 Oct 2024 09:45:57 +0000</pubDate>
        </item>
        <item>
            <title>Question 10, Exercise 5.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit05/ex5-1-p6</link>
            <description>Question 10, Exercise 5.1

Solutions of Question 10 of Exercise 5.1 of Unit 05: Polynomials. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 10
$\left(x^{3}+11 x^{2}+34 x+24\right)$$(x+1)$$p(x)=x^{3}+11 x^{2}+34 x+24$\begin{align}
\begin{array}{r|rrrr}
-1 &amp; 1 &amp; 11 &amp; 34 &amp; 24 \\
&amp; \downarrow  &amp;  -1 &amp; -10 &amp; -24 \\
\hline
&amp; 1 &amp; 10 &amp; 24 &amp;  0 \\
\end{array}\end{align}$$ p(x) = (x+1)(x^2+10…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 10 Oct 2024 09:46:15 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 and 2, Exercise 5.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit05/ex5-2-p1</link>
            <description>Question 1 and 2, Exercise 5.2

Solutions of Question 1 and 2 of Exercise 5.2 of Unit 05: Polynomials. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $y^{3}-7 y-6$$f(y)=y^{3}-7 y-6$\begin{align*}
f(-1)&amp;=(-1)^{3}-7 (-1)-6 \\
&amp;= -1+7-6 =0.
\end{align*}$y+1$$f(y)$\begin{align}
\begin{array}{r|rrrr}
-1 &amp; 1 &amp; 0 &amp; -7 &amp; -6 \\
&amp; \downarrow  &amp;  -1 &amp; 1 &amp; 6 \\
\hline
&amp; 1 &amp; -1 &amp; -6 &amp;  0 \\
\end{array}\end…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 13 Oct 2024 17:52:33 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 and 4, Exercise 5.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit05/ex5-2-p2</link>
            <description>Question 3 and 4, Exercise 5.2

Solutions of Question 3 and 4 of Exercise 5.2 of Unit 05: Polynomials. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $2 x^{3}+5 x^{2}-9 x-18$\( f(x) = 2x^{3} + 5x^{2} - 9x - 18 \)\begin{align*}
f(-2) &amp;= 2(-2)^{3} + 5(-2)^{2} - 9(-2) - 18 \\
&amp;= 2(-8) + 5(4) + 18 - 18 \\
&amp;= -16 + 20 + 18 - 18 = 0.
\end{align*}\( x + 2 \)\( f(x) \)\[
\begin{array}{r|rrrr}
-2 &amp; 2 &amp;…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 13 Oct 2024 17:52:34 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 and 6, Exercise 5.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit05/ex5-2-p3</link>
            <description>;

Question 5 and 6, Exercise 5.2

Solutions of Question 5 and 6 of Exercise 5.2 of Unit 05: Polynomials. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $t^{3}+t^{2}+3 t-5$\( f(t) = t^{3} + t^{2} + 3t - 5 \)\begin{align*}
f(1) &amp;= (1)^{3} + (1)^{2} + 3(1) - 5 \\
&amp;= 1 + 1 + 3 - 5 \\
&amp;= 0.
\end{align*}\( t - 1 \)\( f(t) \)\begin{align}
\begin{array}{r|rrrr}
1 &amp; 1 &amp; 1 &amp; 3 &amp; -5 \\
&amp;   &amp; 1 &amp; 2 &amp; 5 \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 13 Oct 2024 17:52:35 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 and 8, Exercise 5.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit05/ex5-2-p4</link>
            <description>Question 7 and 8, Exercise 5.2

Solutions of Question 7 and 8 of Exercise 5.2 of Unit 05: Polynomials. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $2 x^{3}-15 x^{2}+27 x-10$$\dfrac{1}{2}$\( f(x) \)\( x - \frac{1}{2} \)\begin{align}
\begin{array}{r|rrrr}
\frac{1}{2} &amp; 2 &amp; -15 &amp; 27 &amp; -10 \\
&amp;   &amp; 1   &amp; -7 &amp; 10 \\
\hline
&amp; 2 &amp; -14 &amp; 20 &amp; 0 \\
\end{array}
\end{align}\begin{align*}
f(x) &amp;= \left…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 13 Oct 2024 17:52:35 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 5.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit05/ex5-3-p1</link>
            <description>Question 1, Exercise 5.3

Solutions of Question 1 of Exercise 5.3 of Unit 05: Polynomials. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 1
$x$$x+3$$x+3+7=x+10$$120 cm^3$\begin{align*}
&amp; x(x+3)(x+10)=120 \\
\implies  &amp; x(x^2+3x+10x+30)-120=0\\
\implies &amp; x^3+13x^2+30x-120=0.
\end{align*}$$p(x)=x^3+13x^2+30x-120$$\begin{align*}
p(2)&amp;=2^3+13(2)^2+30(2)-120 \\
&amp;=8+52+60-120 =0
\end{ali…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 13 Oct 2024 17:52:36 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Exercise 5.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit05/ex5-3-p2</link>
            <description>Question 2, Exercise 5.3

Solutions of Question 2 of Exercise 5.3 of Unit 05: Polynomials. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 2
$t(x)=x^{3}-12 x^{2}+48 x+74$$x$$$t(x)=x^{3}-12 x^{2}+48 x+74.$$$t=12$\begin{align*}
t(12)&amp;=(12)^3-12(12)^2+48(12)+74 \\
&amp;=650.
\end{align*}</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 13 Oct 2024 17:52:37 +0000</pubDate>
        </item>
        <item>
            <title>Question 3, Exercise 5.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit05/ex5-3-p3</link>
            <description>Question 3, Exercise 5.3

Solutions of Question 3 of Exercise 5.3 of Unit 05: Polynomials. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 3
$x$$2x$$2x+2$\begin{align*}
&amp; x(2x)(2x+2) = 144 \\
\implies &amp; 4x^2(x+1)=144 \\
\implies &amp; x^2(x+1)=36 \\
\implies &amp; x^3+x^2-36=0
\end{align*}$$p(x)=x^3+x^2-36.$$\begin{align*}
p(3)&amp;=3^3+3^2-36 \\
&amp;=27+9-36 = 0
\end{align*}$x=3$$p(x)$$2(3)$$2(3)+…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 13 Oct 2024 17:52:37 +0000</pubDate>
        </item>
        <item>
            <title>Question 4, Exercise 5.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit05/ex5-3-p4</link>
            <description>Question 4, Exercise 5.3

Solutions of Question 4 of Exercise 5.3 of Unit 05: Polynomials. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 4
$x$$2x+3$$x-2$\begin{align*}
&amp; x(2x+3)(x-2) = 2475 \\
\implies &amp; x(2x^2+3x-4x-6)=2475 \\
\implies &amp; x(2x^2-x-6)-2475=0 \\
\implies &amp; 2x^3-x^2-6x-2475=0
\end{align*}$$p(x)=2x^3-x^2-6x-2475.$$\begin{align*}
p(11)&amp;=2(11)^3-11^2-6(11)-2475 \\
&amp;=2662…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 13 Oct 2024 17:52:37 +0000</pubDate>
        </item>
        <item>
            <title>Question 5, Exercise 5.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit05/ex5-3-p5</link>
            <description>Question 5, Exercise 5.3

Solutions of Question 5 of Exercise 5.3 of Unit 05: Polynomials. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 5
$6 x^{2}+38 x+56$$2 x+8$$ACED$$ABFG$$ACED$$6 x^{2}+38 x+56$$2 x+8$\begin{align*}
&amp; 6 x^{2}+38 x+56 \\
= &amp; 2(3x^2+19x+28) \\
= &amp; 2(3x^2+12x+7x+28) \\
= &amp; 2(3x(x+4)+7(x+4)) \\
=&amp; 2(x+4)(3x+7) \\
=&amp; (2x+8)(3x+7)
\end{align*}\begin{align*}
&amp; Length …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 13 Oct 2024 17:52:38 +0000</pubDate>
        </item>
        <item>
            <title>Question 6, Exercise 5.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit05/ex5-3-p6</link>
            <description>Question 6, Exercise 5.3

Solutions of Question 6 of Exercise 5.3 of Unit 05: Polynomials. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 6
$y^3-2y^2-y+2$$y-2$$=p(y)=y^3-2y^2-y+2$$y-2$$y-2$$p(y)$$2$$p(y)$\[
\begin{array}{r|rrrr}
2 &amp; 1 &amp; -2 &amp; -1 &amp; 2 \\
&amp; \downarrow   &amp; 2 &amp; 0 &amp; -2 \\
\hline
&amp; 1  &amp; 0  &amp; -1 &amp; 0 \\
\end{array}
\]\begin{align*}
p(y) &amp; = (y-2)(y^2-1) \\
&amp; = (y-2)(y+1)(y-1)…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 13 Oct 2024 17:52:38 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit05/ex5-4-p2</link>
            <description>Question 2, Review Exercise

Solutions of Question 2 of Review Exercise of Unit 05: Polynomials. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Go to</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 13 Oct 2024 17:52:38 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit05/re-ex-p1</link>
            <description>Question 1, Review Exercise

Solutions of Question 1 of Review Exercise of Unit 05: Polynomials. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 1
$-2-x+x^{2}$$(x-2)(x-1)$$(x+1)(x+2)$$(x+2)(x-1)$$(x+1)(x-2)$$(x+1)(x-2)$$9 y^{2}+9 y-10$$3 y-2$$ 0$$1$$2$$3$$ 0$$\frac{x^{2}-x-9}{x-3}=x+2+\frac{?}{x-3}$$-27$$-3$$\frac{3}{x-3}+x+2$$ 3$$-3$$3 x^{3}-2 x^{2}+5$$x+1$$x+1$$x^{3}+5 x^{2}-4 x+k$…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 13 Oct 2024 17:52:39 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 &amp; 3, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit05/re-ex-p2</link>
            <description>Question 2 &amp; 3, Review Exercise

Solutions of Question 2 &amp; 3 of Review Exercise of Unit 05: Polynomials. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\left(64 y^{3}-8\right) \div(4 y-2) \quad$\begin{align*}
\frac{(64 y^{3}-8)}{(4 y-2)}&amp;= \frac{(4y - 2)(16y^{2} + 8y + 4)}{4y - 2}\\
&amp; = 16y^{2} + 8y + 4 .\end{align*}$\left(125 y^{3}-8\right) \div(5 y-2)$\begin{align*}
\frac{(125 y^{3}-8)}{(5 …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 13 Oct 2024 17:52:39 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 &amp; 5, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit05/re-ex-p3</link>
            <description>Question 4 &amp; 5, Review Exercise

Solutions of Question 4 &amp; 5 of Review Exercise of Unit 05: Polynomials. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $3 y-2$$6 y^{3}-y^{2}-5 y+2$\begin{align*}3y-2&amp;=0\\
3y&amp;=2\\
y&amp;=\frac{2}{3}\end{align*}\begin{align*}
f(y) &amp;= 6y^{3} - y^{2} - 5y + 2\\
f\left(\frac{2}{3}\right) &amp;= 6\left(\frac{2}{3}\right)^{3} - \left(\frac{2}{3}\right)^{2} - 5\left(\frac{2}{3…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 13 Oct 2024 17:52:40 +0000</pubDate>
        </item>
        <item>
            <title>Question 6 &amp; 7, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit05/re-ex-p4</link>
            <description>Question 6 &amp; 7, Review Exercise

Solutions of Question 6 &amp; 7 of Review Exercise of Unit 05: Polynomials. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $k$$\left(x^{2}+8 x+k\right)$$(x-4)$\( p(x) = x^{2} + 8x + k \)\( p(x) \)\( (x - 4) \)\( p(4) \)\( p(4) = 0 \)\begin{align*}
p(4) &amp;= (4)^2 + 8(4) + k \\
&amp;= 16 + 32 + k \\
&amp;= 48 + k.
\end{align*}\[
48 + k = 0.
\]\[
k = -48.
\]$3 x^{2}-x+32-\frac…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 13 Oct 2024 17:52:40 +0000</pubDate>
        </item>
        <item>
            <title>Question 8, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit05/re-ex-p5</link>
            <description>Question 8, Review Exercise

Solutions of Question 8 of Review Exercise of Unit 05: Polynomials. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 8
$y^{3}+6 y^{2}-y-30$$(y-2)$$(y+3)$$p(y)=y^{3}+6 y^{2}-y-30$$(y-2)$$(y+3)$$p(y)$$2$$-3$$p(y)$\[
\begin{array}{r|rrrr}
2 &amp; 1 &amp; 6 &amp; -1 &amp; -30 \\
 &amp; \downarrow   &amp; 2  &amp; 16 &amp; 30  \\
\hline
-3 &amp; 1  &amp; 8  &amp; 15 &amp; 0 \\
 &amp; \downarrow   &amp; -3  &amp; -15 &amp;  …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 13 Oct 2024 17:52:41 +0000</pubDate>
        </item>
        <item>
            <title>Question 6, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit05/re-ex-p6</link>
            <description>Question 6, Review Exercise

Solutions of Question 6 of Review Exercise of Unit 05: Polynomials. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 6
$k$$\left(x^{2}+8 x+k\right)$$(x-4)$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 13 Oct 2024 17:52:42 +0000</pubDate>
        </item>
        <item>
            <title>Question 7, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit05/re-ex-p7</link>
            <description>Question 7, Review Exercise

Solutions of Question 7 of Review Exercise of Unit 05: Polynomials. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 7
$3 x^{2}-x+32-\frac{121}{x+4}$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 13 Oct 2024 17:52:42 +0000</pubDate>
        </item>
        <item>
            <title>Question 8, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit05/re-ex-p8</link>
            <description>Question 8, Review Exercise

Solutions of Question 8 of Review Exercise of Unit 05: Polynomials. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. 

Question 8
$y^{3}+6 y^{2}-y-30$$(y-2)$$(y+3)$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 13 Oct 2024 17:52:43 +0000</pubDate>
        </item>
        <item>
            <title>Exercise 6.1 (Solutions)</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-1</link>
            <description>Exercise 6.1 (Solutions)

The solutions of the Exercise 6.1 of book “Model Textbook of Mathematics for Class XI” published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan are given on this page. This exercise consists of the question related to factorial function.$n!$$$
n!=\left\{\begin{array}{l}
n(n-1)(n-2)\cdot \ldots \cdot 3 \cdot 2 \cdot 1 \text{ if } n\geq 1,\\
1 \text{ if } n=0.
\end{array} \right.
$$$10!$$\dfrac{12!}{7! 3! 2!}$$\dfrac{4!-2!}{3!+5!}$$\dfrac…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 08:59:40 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 6.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-1-p1</link>
            <description>Question 1, Exercise 6.1

Solutions of Question 1 of Exercise 6.1 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $10!$\begin{align*} 
10! &amp;= 10 \times 9 \times 8 \times 7 \times 6 \times 5 \times 4 \\
&amp;= 3628800
\end{align*}$\dfrac{12!}{7! 3! 2!}$\begin{align*}
\dfrac{12!}{7! \, 3! \, 2!} &amp;= \dfrac{12 \times 11 \times 10 \times 9 \times 8 \times 7!}{7! …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 08:59:29 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Exercise 6.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-1-p2</link>
            <description>Question 2, Exercise 6.1

Solutions of Question 2 of Exercise 6.1 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\quad 14\cdot 13\cdot 12\cdot 11$\begin{align*}
&amp;14\cdot 13\cdot 12\cdot 11\\
= &amp; \dfrac{14\cdot 13\cdot 12\cdot 11\cdot 10!}{10!} \\
= &amp; \dfrac{14!}{10!} 
\end{align*}$\quad 1\cdot 3\cdot 5 \cdot 7 \cdot 9$$$1 \times 3\times 5\times 7 \time…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 08:59:29 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 and 4, Exercise 6.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-1-p3</link>
            <description>Question 3 and 4, Exercise 6.1

Solutions of Question 3 and 4 of Exercise 6.1 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\quad \dfrac{1}{5!}+\dfrac{3}{6!}+\dfrac{1}{7!}=\dfrac{4}{315}$\begin{align*}
LHS = &amp; \dfrac{1}{5!}+\dfrac{3}{6!}+\dfrac{1}{7!} \\
= &amp; \dfrac{1}{5!}+\dfrac{3}{6\cdot 5!}+\dfrac{1}{7\cdot 6\cdot 5!}\\
= &amp; \dfrac{1}{5!}\left(1+\dfr…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 08:59:31 +0000</pubDate>
        </item>
        <item>
            <title>Question 5, Exercise 6.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-1-p4</link>
            <description>Question 5, Exercise 6.1

Solutions of Question 5 of Exercise 6.1 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $n$$\quad \dfrac{n}{(n-4)!}=\dfrac{3.3!}{(n-3)!}$\begin{align*}
\dfrac{n}{(n-4)!}&amp;=\dfrac{3.3!}{(n-3)!}\\
\dfrac{n}{(n-4)!}&amp;=\dfrac{3.3!}{(n-3)(n-4)!}\\
n&amp;=\dfrac{3\times 6}{n-3}\\
n(n-3)&amp;=18\\
n^2-3n&amp;=18\\
n^2-2n-18&amp;=0\\
n^2+3n-6n-18&amp;=0\\
n(…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 08:59:34 +0000</pubDate>
        </item>
        <item>
            <title>Question 6(i-v), Exercise 6.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-1-p5</link>
            <description>Question 6(i-v), Exercise 6.1

Solutions of Question 6(i-v) of Exercise 6.1 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $n\in N$$\quad (2n)!=2^n(n!)[1\cdot3\cdot5 \cdots (2n-1)]$\begin{align*}
(2n)!&amp;= (2n)(2n-1)(2n-2)(2n-3)\cdots (2n-n)(2n-(n+1))\cdots4.3.2.1\\
&amp;= (2n)(2n-1)(2n-2)(2n-3)\cdots (n)(n-1)\cdots4.3.2.1\\
&amp;= (2n)(2n-1)(2n-2)(2n-3)\cdots (n…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 08:59:32 +0000</pubDate>
        </item>
        <item>
            <title>Question 6(vi-ix), Exercise 6.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-1-p6</link>
            <description>Question 6(vi-ix), Exercise 6.1

Solutions of Question 6(vi-ix) of Exercise 6.1 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $n\in N$$\quad 33!$$2^{15}$$$33!=33.32.31\cdots4.3.2.1$$$2,4,8,16,32$$2^1,2^2,2^3,2^4,2^5$\begin{align*}33!&amp;=2^5.2^4.2^3.2^2.2(33\times31\times\cdots6\times5\times3\times1)\\
&amp;=2^{15}(33\times31\times\cdots\times3\times1)\end{al…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 08:59:34 +0000</pubDate>
        </item>
        <item>
            <title>Question 7(i-vi), Exercise 6.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-1-p7</link>
            <description>Question 7(i-vi), Exercise 6.1

Solutions of Question 7(i-vi) of Exercise 6.1 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $n$$\quad \dfrac{n!}{(n-2)!}=930,\quad n \geq 2$\begin{align*}
\dfrac{n!}{(n-2)!}&amp;=930\\
\dfrac{n(n-1)(n-2)!}{(n-2)!}&amp;=930\\
n(n-1)&amp;=930\\
n^2-n-930&amp;=0
\end{align*}\begin{align*}
n&amp;=\dfrac{1\pm \sqrt{1+4(930)}}{2}\\
&amp;=\dfrac{1\pm …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 08:59:37 +0000</pubDate>
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        <item>
            <title>Question 7(vii-xi), Exercise 6.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-1-p8</link>
            <description>Question 7(vii-xi), Exercise 6.1

Solutions of Question 7(vii-xi) of Exercise 6.1 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $n$$\quad n!=990 \cdot (n-3)!$\begin{align*}
n!&amp;=990  (n-3)!\\
n(n-1)(n-1)(n-3)!&amp;=990  (n-3)!\\
n(n-1)(n-1)&amp;=990 \\
n^3-3n^2+2n-990 &amp;=0\\
\end{align*}\[\begin{array}{c|cccc}
 &amp; 1 &amp; -3 &amp; 2 &amp; -990 \\  
11 &amp; 0  &amp; 11 &amp; 88 &amp; 990 \\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 08:59:36 +0000</pubDate>
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        <item>
            <title>Exercise 6.2 (Solutions)</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-2</link>
            <description>Exercise 6.2 (Solutions)

The solutions of the Exercise 6.1 of book “Model Textbook of Mathematics for Class XI” published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan are given on this page. This exercise consists of the question related to factorial function.$n!$$$
n!=\left\{\begin{array}{l}
n(n-1)(n-2)\cdot \ldots \cdot 3 \cdot 2 \cdot 1 \text{ if } n\geq 1,\\
1 \text{ if } n=0.
\end{array} \right.
$$$n \in \mathbb{N}$${ }^n P_r=\frac{n!}{(n-r)!}$$\quad{ }^…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 08:59:59 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 6.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-2-p1</link>
            <description>Question 1, Exercise 6.2

Solutions of Question 1 of Exercise 6.2 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $n \in N$$\quad^nP_r=\dfrac{n!}{(n-r)!}$$n$$r$$\dot{n}$$2^{\text {nd }}$$(n-1)$$3^{\text {rd }}$$(n-2)$$r^{\text {th }}$$(n-(r-1)$$$
{ }^{n} P_{r}=n(n-1)(n-2) \ldots(n-(r-1))
$$$(n-r)(n-r-1) \ldots 3,2.1$${ }^{n} P_{r}=\frac{n(n-1)(n-2)\ldots…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 08:59:40 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Exercise 6.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-2-p2</link>
            <description>Question 2, Exercise 6.2

Solutions of Question 2 of Exercise 6.2 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $n$$\quad ^nP_4=20\, ^nP_2$\begin{align*}
\dfrac{m}{(n-4)!}&amp;=20 \cdot \dfrac{m}{(n-2)!}\\
\dfrac{1}{(n-4)!}&amp;=\dfrac{20}{(n-2)(n-3)(n-4)!}\\
(n-2)(n-3)&amp;=20\\
n^{2}-5 n+6&amp;=20\\
n^{2}-5 n-14&amp;=0\\
n^{2}+2 n-7 n-14&amp;=0\\
n(n+2)-7(n+2)&amp;=0\\
(n+2)(n-…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 08:59:49 +0000</pubDate>
        </item>
        <item>
            <title>Question 3, Exercise 6.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-2-p3</link>
            <description>Question 3, Exercise 6.2

Solutions of Question 3 of Exercise 6.2 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $r$$^6P_{r-1}=^5P_4$\begin{align*}{ }^{6} P_{r-1}&amp;={ }^{5} P_{4}\\
\dfrac{6!}{(6-(r-1))!}&amp;=\dfrac{5!}{(5-4)!}\\
\dfrac{6!}{(7-r)!}&amp;=\dfrac{5!}{1!} \\
\frac{6 \times 5!}{(7-r)!}=\dfrac{5!}{1}
6&amp;=(7-r)!\\
3!&amp;=(7-r)!\\
3&amp;=7-r \\
r&amp;=7-3\\
r&amp;=4\en…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 08:59:50 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 and 5, Exercise 6.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-2-p4</link>
            <description>Question 4 and 5, Exercise 6.2

Solutions of Question 4 and 5 of Exercise 6.2 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $3$$1,2,3,4,5,6,$$3$$6$$\mathrm{I}:$$2$$$\underline{ },\underline{ },\underline{2}$$$={ }^{5} P_{2}=20$$4$$$\underline{ },\underline{ },\underline{4}$$$={ }^{5} P_{2}=20$$6$$$\underline{ },\underline{ },\underline{6}$$$={ }^{5} P_…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 08:59:51 +0000</pubDate>
        </item>
        <item>
            <title>Question 6 and 7, Exercise 6.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-2-p5</link>
            <description>Question 6 and 7, Exercise 6.2

Solutions of Question 6 and 7 of Exercise 6.2 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $4$$$1,2,3,4,5,6$$6$$6$$6$$6$$$\text{Total possibilities }6 \times 6 \times 6 \times 6=6^4=1296$$$1,1,2,2,3,3,4$$=7$$2^{\text {nd }}$$6^{\text {th }}$$1^{\text {st }}, 3^{\text {rd }}, 5^{\text {th }}$$7^{\text {th }}$$2,2,4$$1,1,…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 08:59:54 +0000</pubDate>
        </item>
        <item>
            <title>Question 8 and 9, Exercise 6.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-2-p6</link>
            <description>Question 8 and 9, Exercise 6.2

Solutions of Question 8 and 9 of Exercise 6.2 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $4$$5$$5$$4$$41$$=41 \times 41=576$$2$$3$$4$$$\text{Total flags} =9$$$$\text{Repetition of blue }=2$$$$\text{Repetition of yellow}=3$$$$\text{Repetition of green}=4$$\begin{align*}\text{Total signals }&amp;=\dfrac{9!}{2!3!4!}\\
&amp;=\dfr…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 08:59:54 +0000</pubDate>
        </item>
        <item>
            <title>Question 10 and 11, Exercise 6.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-2-p7</link>
            <description>Question 10 and 11, Exercise 6.2

Solutions of Question 10 and 11 of Exercise 6.2 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $=6$$={ }^{6}{ }^{1} P_{5}=6$$720$$F$$F$$5$$5!=120$$=9$$S=2$$T=2$$A=2$\begin{align*}\text{possible permutation}&amp;=\dfrac{9!}{2!2!2!}\\
&amp;=\dfrac{362880}{8}\\
&amp;=45360\end{align*}</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 08:59:56 +0000</pubDate>
        </item>
        <item>
            <title>Question 12 and 13, Exercise 6.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-2-p8</link>
            <description>Question 12 and 13, Exercise 6.2

Solutions of Question 12 and 13 of Exercise 6.2 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $=5$$5$$=5!=120$$O$$E$$21=2$$3$$3!= 6$$O$$E$$=6 \times 2=12$$0$$E$$=120-12=108$$=7$$7$$=71=5040$$3$$A, I$$E$$3$$4$$$5!=120$$$3$$=6$$$6 \times 120=\mathbf{7 2 0}$$$5040$$720$$3$$5040-720=4320$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 08:59:55 +0000</pubDate>
        </item>
        <item>
            <title>Question 14 and 15, Exercise 6.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-2-p9</link>
            <description>Question 14 and 15, Exercise 6.2

Solutions of Question 14 and 15 of Exercise 6.2 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $3$$=7$$=3$$={ }^{7} P_{3}=\dfrac{7!}{4!}=210$$5$$3$$2$$3$$=31=6$$=(5!\times 3!\times 2!) \times 31=8640$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 08:59:57 +0000</pubDate>
        </item>
        <item>
            <title>Question 16 and 17, Exercise 6.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-2-p10</link>
            <description>Question 16 and 17, Exercise 6.2

Solutions of Question 16 and 17 of Exercise 6.2 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $1,2,3,4,5,6$$1, 3$$5$$=3 \times{ }^{5} P_{5}=360$$4$$1,2,3,4$$5$$1$$={ }^{4} P_{3}=24$$3$$24$$5$$24$$24+24+24=72$$4$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 08:59:43 +0000</pubDate>
        </item>
        <item>
            <title>Question 18 and 19, Exercise 6.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-2-p11</link>
            <description>Question 18 and 19, Exercise 6.2

Solutions of Question 18 and 19 of Exercise 6.2 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $10,000$$0,2,3,5,6$$4$$10000$$3$$5$$0$$3={ }^{3} P=6$$0$$5=3 p_{6}=6$$10000$$5$$=6+6=12$$3$$4$$5$$={ }^{4} P_{3}=2$$4$$5$$4$$5={ }^{4} P_{3}=24$$3$$3$$3$$5=$${ }^{4} P_{2}=12$$3$$5$$3$$5=$${ }^{4} P_{2}=12$$2$$3$$2$$5={ }^{4} …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 08:59:48 +0000</pubDate>
        </item>
        <item>
            <title>Question 20 and 21, Exercise 6.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-2-p12</link>
            <description>Question 20 and 21, Exercise 6.2

Solutions of Question 20 and 21 of Exercise 6.2 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $6$$6$$5!$$6$$6!$$=5! \times 6!=86400$$= n = 4$$= {}^4P_4 = 24.$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 08:59:45 +0000</pubDate>
        </item>
        <item>
            <title>Question 22 and 23, Exercise 6.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-2-p13</link>
            <description>Question 22 and 23, Exercise 6.2

Solutions of Question 22 and 23 of Exercise 6.2 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $(3\quad 4\quad 6\quad 1\quad 5\quad2)$$1$$2$$L=1, A=2, H=3, O=4, R=5, E=6$$(3,4,6,1,5,2)=$$(4\quad 6\quad 3\quad 2\quad 1\quad5)$$(4,6,3,2,1,5)$$4^{\text {th }}$$2^{\text {nd }}$$6^{\text {th }}$$3^{\text {rd }}$$3^{\text {rd…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 08:59:46 +0000</pubDate>
        </item>
        <item>
            <title>Exercise 6.3 (Solutions)</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-3</link>
            <description>Exercise 6.3 (Solutions)

The solutions of the Exercise 6.3 of book “Model Textbook of Mathematics for Class XI” published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan are given on this page. This exercise consists of the question related to factorial function.$n \in \mathbb{N}$${ }^{n} C_{r}=\frac{n!}{r!(n-r)!}$$n,{ }^{n-1} C_{r-1}=(n-r+1){ }^{n} C_{r-1}$$r^{n} C_{r}=(n-r+1)^{n} C_{r-1}$${ }^{n-1} C_{r-1}+{ }^{n-1} C_{r}={ }^{n} C_{r}$${ }^{n} C_{r}+{ }^{n} C…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 09:00:35 +0000</pubDate>
        </item>
        <item>
            <title>Question 1(i-v), Exercise 6.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-3-p1</link>
            <description>Question 1(i-v), Exercise 6.3

Solutions of Question 1(i-v) of Exercise 6.3 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $n\in N$$\quad^nC_r=\dfrac{n!}{r!(n-r)!}$$n$$r$$0&lt;r&lt;n$$X$$r$$r$$r$$$
\begin{array}{ll} 
&amp; r!X={ }^{n} P_{r} \\
\Rightarrow &amp; r!X=\frac{n!}{(n-r)!} \\
\Rightarrow &amp; X=\frac{n!}{r!(n-r)!}={ }^{n}{C}_{r}
\end{array}
$$$n\in N$$n\cdot^{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 09:00:24 +0000</pubDate>
        </item>
        <item>
            <title>Question 1(vi-x), Exercise 6.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-3-p2</link>
            <description>Question 1(vi-x), Exercise 6.3

Solutions of Question 1(vi-x) of Exercise 6.3 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $n\in N$$\quad^{2n}C_n=\dfrac{2^n[1.3.5.\cdots(2n-1)]}{n!}$\begin{align*}L.H.S &amp;=\quad^{2n}C_n \\
&amp;=\dfrac{(2 n)!}{n!(2 n-n)!}\\
&amp;=\dfrac{(2 n)(2 n-1)(2 n-2)(2 n-n)(2 n-(n+1)) ..2 .1}{n!\cdot n!}\\
&amp;=\dfrac{(2 n)(2 n-1)(2 n-2) ..(…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 09:00:26 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Exercise 6.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-3-p3</link>
            <description>Question 2, Exercise 6.3

Solutions of Question 2 of Exercise 6.3 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $n$$\,\, ^nC_5=\,\, ^nC_8$\begin{align*}\dfrac{n!}{5!(n-5)!}=\dfrac{n!}{8!(n-8)!}&amp;\\
\dfrac{1}{8!(n-5)(n-6)(n-7)(n-8)!}&amp;\\
=\dfrac{1}{8 \times 7 \times 6 \times 8!(n-8)!}&amp;\\
336=(n-5)(n-6)(n-7)&amp;\\
(n-5)\left(n^{2}-13 n+42\right)&amp;=336\\
n^{3}-…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 09:00:26 +0000</pubDate>
        </item>
        <item>
            <title>Question 3, Exercise 6.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-3-p4</link>
            <description>Question 3, Exercise 6.3

Solutions of Question 3 of Exercise 6.3 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $r$$\quad^{15}C_{3r}= ^{15}C_{3+r}$$${ }^{n} C_{r}={ }^{n} C_{n-r}$$\begin{align*}n=15\quad&amp;\text{put} \quad r=3 r\\
n-3 r&amp;=r+3\\
15-3 r&amp;=r+3 \\
15-3 &amp; =3 r+r \\
12 &amp; =4 r\\
r&amp;=3\end{align*}$r$$\quad^{8}C_{r}-\,^7C_3= ^{7}C_{2}$\begin{align*}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 09:00:27 +0000</pubDate>
        </item>
        <item>
            <title>Question 4, Exercise 6.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-3-p5</link>
            <description>Question 4, Exercise 6.3

Solutions of Question 4 of Exercise 6.3 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $n$$r$$\,\,^nC_{r-1}:\,^nC_{r}:\,^nC_{r+1}=6:14:21$\begin{align*}\dfrac{n!}{(r-1)!(n-(r-1))!}&amp;: \dfrac{n!}{r!(n-r)!}\\
: \dfrac{n!}{(r+1)!(n-(r+1))!} &amp;= 6:14:21\\
\dfrac{1}{(r-1)!(n-r+1)!}: \dfrac{1}{r!(n-r)!}&amp;\\
: \dfrac{1}{(r+1)!(n-r-1)!}&amp;=…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 09:00:27 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 and 6, Exercise 6.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-3-p6</link>
            <description>Question 5 and 6, Exercise 6.3

Solutions of Question 5 and 6 of Exercise 6.3 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $11$$16$$11$$16$${ }^{16} C_{11}$$4368$$11$$11$$16$$10$$15$$$
{ }^{15} C_{10}=3003
$$$5$$3$$3$$1$${ }^{5} C_{1}$$2$${ }^{3} C_{2}$$={ }^{5} C_{1} \times{ }^{3} C_{2}=5 \times 3=15$$2$$={ }^{5} C_{2} \times{ }^{3} C_{1}=10 \times 3…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 09:00:29 +0000</pubDate>
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        <item>
            <title>Question 7 and 8, Exercise 6.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-3-p7</link>
            <description>Question 7 and 8, Exercise 6.3

Solutions of Question 7 and 8 of Exercise 6.3 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $5$$6$$4$$2$$2$$3$$={ }^{4} C_{2} \times{ }^{6} C_{3}=6 \times 20=120$$5$$6$$4$$2$$2$$2$$2,3$$2$$120$$3$$2$$={ }^{4} C_{3} \cdot{ }^{6} C_{2}=4 \times 15=60$$4$$={ }^{4} C_{4} \times{ }^{6} C_{1}=1 \times 6=6$$=120+60+6=186$$5$$6$…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 09:00:29 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 and 10, Exercise 6.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-3-p8</link>
            <description>Question 9 and 10, Exercise 6.3

Solutions of Question 9 and 10 of Exercise 6.3 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $n$$n$$n$$n$$C_{2}$$n$$n$$={ }^{n} C_{2}-n$$=\frac{n!}{2!(n-2)!}-n$$10$$10$$3$$7$$10$${ }^{10} C_{7}$$7$$3$$7={ }^{10} C_{7}=120$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 09:00:33 +0000</pubDate>
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        <item>
            <title>Question 11 and 12, Exercise 6.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-3-p9</link>
            <description>Question 11 and 12, Exercise 6.3

Solutions of Question 11 and 12 of Exercise 6.3 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $n$$35$$n$\begin{align*}{ }^{n} C_{2}-n&amp;=35\\
\text{or} \quad \dfrac{n!}{2!(n-2)!}-n&amp;=35\\
\dfrac{n(n-1)(n-2)!}{2(n-2)!}-n&amp;=35\\
\dfrac{n(n-1)-2 n}{2}&amp;=35\\
n^{2}-n-2 n&amp;=70\\
n^{2}-3 n-70&amp;=0\\
n^{2}+7 n-10 n-70 &amp; =0 \\
n(n+7)-…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 09:00:31 +0000</pubDate>
        </item>
        <item>
            <title>Question 13 and 14, Exercise 6.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/ex6-3-p10</link>
            <description>Question 13 and 14, Exercise 6.3

Solutions of Question 13 and 14 of Exercise 6.3 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $6$$1$$1$$2$$6$$1$$6={ }^{6} C_{1}=6$$2$$6={ }^{6} C_{2}=15$$3$$6={ }^{6} C_{3}=20$$4$$6={ }^{6} C_{4}=15$$5$$6={ }^{6} C_{5}=6$$6$$6={ }^{6} C_{6}=1$$$\text{Total}\quad =6+15+20+15+6+1=63$$$A$$B$$C$$8$$5$$A$$3$$B$$C$$5$$8$$A$…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 09:00:22 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Review Exercise 6</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/re-ex6-p1</link>
            <description>Question 1, Review Exercise 6

Solutions of Question 1 of Review Exercise 6 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $3\,\,^nP_3=^nP_4$$n$$5$$6$$7$$8$$6$$ 480$$600$$720$$840$$720$$r$$r!$$(r+1)!$$r!+1$$ 2r!$$r!$$6$$\dfrac{5}{2}\,\,6!$$6!$$\dfrac{1}{2}\,\,6!$$\dfrac{3}{2}\,\,6!$$\dfrac{5}{2}\,\,6!$$A=\{1,2,3,4,...,20\}. $$3$$5$$7$$8$$8$$A=\{1,3,5,7,…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 09:00:36 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 and 3, Review Exercise 6</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/re-ex6-p2</link>
            <description>Question 2 and 3, Review Exercise 6

Solutions of Question 2 and 3 of Review Exercise 6 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $4$$26$$$^{26}P_4=358800$$$3$$0$$3$$100&#039;s$$9$$3$$$=10\times 10\times10=1000$$$0$$10$$3-$$0$$$=10\times 10=100$$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 09:00:43 +0000</pubDate>
        </item>
        <item>
            <title>Question 4, 5 and 6, Review Exercise 6</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/re-ex6-p3</link>
            <description>Question 4, 5 and 6, Review Exercise 6

Solutions of Question 4, 5 and 6 of Review Exercise 6 of Unit 06: Permutation and Combination. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $0,2,3,4,5,7$$6$$$=6!=720$$$0$$5$$$5!=120$$$6-$$$=720-120=600$$$7$$$(7-1)!=720$$$2$$$\dfrac{720}{2}=360$$$11!$$10!$$$=11!-10!=36288000$$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 09:00:38 +0000</pubDate>
        </item>
        <item>
            <title>Review Exercise (Solutions)</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit06/rev-ex</link>
            <description>Review Exercise (Solutions)

The solutions of the Review Exercise of book “Model Textbook of Mathematics for Class XI” published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan are given on this page. 

Question 1.$4$$3$$0$$6$$0,2,3,4,5,7$$7$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Mar 2025 09:00:41 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 8.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-1-p1</link>
            <description>Question 1, Exercise 8.1

Solutions of Question 1 of Exercise 8.1 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\cos (\alpha \pm \beta), \sin (\alpha \pm \beta)$$\tan (\alpha \pm \beta)$$\alpha=180^{\circ}, \beta=60^{\circ}$$\alpha=180^{\circ}$$\beta=60^{\circ}$\begin{align*}
 \cos (\alpha + \beta) &amp; = \cos \alpha \cos \beta - \sin \alpha \sin \beta \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 20 Oct 2024 17:53:30 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Exercise 8.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-1-p2</link>
            <description>Question 2, Exercise 8.1

Solutions of Question 2 of Exercise 8.1 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\cos 15^{\circ}$$\cos \left(45^{\circ}-30^{\circ}\right)$\begin{align*}
\cos 15^{\circ} &amp; = \cos \left(45^{\circ}-30^{\circ}\right)\\
&amp;= \cos 45 \cos 30 + \sin 45 \sin 30 \\
&amp;= \dfrac{1}{\sqrt{2}}\cdot \dfrac{\sqrt{3}}{2} + \dfrac{1}{\sqrt{2…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 20 Oct 2024 17:53:35 +0000</pubDate>
        </item>
        <item>
            <title>Question 3, Exercise 8.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-1-p3</link>
            <description>Question 3, Exercise 8.1

Solutions of Question 3 of Exercise 8.1 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\cos 120^{\circ}$$\cos \left(180^{\circ}-60^{\circ}\right)$$\cos \left(90^{\circ}+30^{\circ}\right)$\begin{align*}
\cos 120^{\circ} &amp; = \cos \left(180^{\circ}-60^{\circ}\right) \\
&amp;= - \cos 60 ^{\circ}\\
&amp;= -\dfrac{1}{2}.
\end{align*}\begin{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 20 Oct 2024 17:53:37 +0000</pubDate>
        </item>
        <item>
            <title>Question 4, Exercise 8.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-1-p4</link>
            <description>Question 4, Exercise 8.1

Solutions of Question 4 of Exercise 8.1 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\cos 6 \theta \cos 3 \theta-\sin 6 \theta \sin 3 \theta$\begin{align*}
&amp; \cos 6 \theta \cos 3 \theta-\sin 6 \theta \sin 3 \theta \\
&amp; = \cos (6\theta +3\theta) \\
&amp; = \cos 9\theta .
\end{align*}$\cos 7 \theta \cos 2 \theta+\sin 7 \theta \sin…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 20 Oct 2024 17:53:38 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 and 6, Exercise 8.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-1-p5</link>
            <description>Question 5 and 6, Exercise 8.1

Solutions of Question 5 and 6 of Exercise 8.1 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\sin \alpha=\dfrac{4}{5}, \tan \beta=-\dfrac{5}{12}$$\cos (\alpha+\beta)$$\cos (\alpha-\beta)$$\sin \alpha=\dfrac{4}{5}$$\alpha$$\tan \beta=-\dfrac{5}{12}$$\beta$$$\cos \alpha=\pm \sqrt{1-\sin^2\alpha}.$$$\alpha$$\cos$\begin{alig…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 20 Oct 2024 17:53:39 +0000</pubDate>
        </item>
        <item>
            <title>Question 7, Exercise 8.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-1-p6</link>
            <description>Question 7, Exercise 8.1

Solutions of Question 7 of Exercise 8.1 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\alpha$$\beta$$\sin \alpha=\dfrac{12}{13}$$\tan \beta=\dfrac{4}{3}$$\sin(\alpha+\beta)$$\cos(\alpha+\beta)$$\tan(\alpha+\beta)$$\sin \alpha=\dfrac{12}{13}$$\alpha$$\tan \beta=\dfrac{4}{3}$$\beta$$$\cos \alpha=\pm \sqrt{1-\sin^2\alpha}.$$\(\a…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 20 Oct 2024 17:53:39 +0000</pubDate>
        </item>
        <item>
            <title>Question 8, Exercise 8.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-1-p7</link>
            <description>Question 8, Exercise 8.1

Solutions of Question 8 of Exercise 8.1 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\sin \alpha=\dfrac{3}{5}$$0&lt;\alpha&lt;\dfrac{\pi}{2}$$\cos \beta=\dfrac{12}{13}$$\dfrac{3 \pi}{2}&lt;\beta&lt;2 \pi$$\csc (\alpha+\beta)$$\sec (\alpha+\beta)$$\cot (\alpha+\beta)$$\sin \alpha=\dfrac{3}{5}$$0&lt;\alpha&lt;\dfrac{\pi}{2}$$\alpha$\begin{align…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 20 Oct 2024 17:53:41 +0000</pubDate>
        </item>
        <item>
            <title>Question 9, Exercise 8.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-1-p8</link>
            <description>Question 9, Exercise 8.1

Solutions of Question 9 of Exercise 8.1 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\alpha$$\beta$$\sin \alpha=\dfrac{1}{\sqrt{2}}$$\cos \beta=-\dfrac{3}{5}$$\sin (\alpha \pm \beta)$$\sin \alpha=\dfrac{1}{\sqrt{2}}$$\alpha$$\cos \beta=-\dfrac{3}{5}$$\beta$$$\cos \alpha=\pm \sqrt{1-\sin^2\alpha}.$$$\alpha$$\cos$\begin{align*…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 20 Oct 2024 17:53:41 +0000</pubDate>
        </item>
        <item>
            <title>Question 10, Exercise 8.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-1-p9</link>
            <description>Question 10, Exercise 8.1

Solutions of Question 10 of Exercise 8.1 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\sin \left(\dfrac{\pi}{2}-\alpha\right)=\cos \alpha$\begin{align*}
L.H.S &amp; = \sin \left(\frac{\pi}{2}-\alpha\right) \\
&amp; =\sin\frac{\pi}{2} \cos \alpha - \cos \frac{\pi}{2} \sin\alpha \\
&amp; = 1\times \cos \alpha - 0 \times \sin\alpha \\
&amp; =…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 20 Oct 2024 17:53:42 +0000</pubDate>
        </item>
        <item>
            <title>Question 11, Exercise 8.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-1-p10</link>
            <description>Question 11, Exercise 8.1

Solutions of Question 11 of Exercise 8.1 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\dfrac{\sin \left(180^{\circ}+\lambda\right) \cos \left(270^{\circ}+\lambda\right)}{\sin \left(180^{\circ}-\lambda\right) \cos \left(270^{\circ}-\lambda\right)}=1$\begin{align*}
L.H.S &amp; = \dfrac{\sin \left(180^{\circ}+\lambda\right) \cos \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 20 Oct 2024 17:53:31 +0000</pubDate>
        </item>
        <item>
            <title>Question 12, Exercise 8.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-1-p11</link>
            <description>Question 12, Exercise 8.1

Solutions of Question 12 of Exercise 8.1 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\alpha+\beta+\gamma=180^{\circ}$$\tan \alpha+\tan \beta+\tan \gamma=\tan \alpha \tan \beta \tan \gamma$$$\alpha+\beta+\gamma=180^{\circ}$$\begin{align*}
&amp; \alpha+\beta=180^{\circ}-\gamma \\
\implies &amp; \tan(\alpha+\beta) = \tan(180^{\circ}-…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 20 Oct 2024 17:53:31 +0000</pubDate>
        </item>
        <item>
            <title>Question 13, Exercise 8.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-1-p12</link>
            <description>Question 13, Exercise 8.1

Solutions of Question 13 of Exercise 8.1 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $r \sin (\theta+\phi)$$12 \sin \theta-5 \cos \theta$$12=r\cos \varphi $$-5=r\sin \varphi$\begin{align*}
&amp; (12)^2+(-5)^2=r^2 \cos^2\varphi+r^2 \sin^2 \varphi \\
\implies &amp; 144+25={{r}^{2}}\left( {{\cos }^{2}}\varphi +{{\sin }^{2}}\varphi  \r…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 20 Oct 2024 17:53:32 +0000</pubDate>
        </item>
        <item>
            <title>Question 14, Exercise 8.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-1-p13</link>
            <description>Question 14, Exercise 8.1

Solutions of Question 14 of Exercise 8.1 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\theta$$\sin \theta$$\cos \theta$$\alpha$\begin{align*}
&amp;\tan\alpha = \frac{\overline{BC}}{\overline{AB}} \\
\implies &amp;\tan\alpha = \frac{3}{3} = 1 \\
\implies &amp;\alpha = \tan^{-1}(1) = 45^\circ
\end{align*}$45^\circ$$\theta$\begin{align*}
…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 20 Oct 2024 17:54:47 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, 2 and 3 Exercise 8.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-2-p1</link>
            <description>Question 1, 2 and 3 Exercise 8.2

Solutions of Question 1, 2 and 3 of Exercise 8.2 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $P(-3,4)$$\theta$$\theta$$\cos 2 \theta$$\sin 2 \theta$$2 \theta$$x=-3$$y=4$\begin{align*}
r&amp;= \sqrt{(-3)^2+4^2} \\
&amp;=\sqrt{25} = 5.
\end{align*}$$\sin\theta = \frac{4}{5} \text{ and } \cos\theta = -\frac{3}{5}.$$\begin{align…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 26 Oct 2024 18:54:35 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 Exercise 8.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-2-p2</link>
            <description>Question 4 Exercise 8.2

Solutions of Question 4 of Exercise 8.2 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\sin 2 \theta$$\cos 2 \theta$$\tan 2 \theta$$\sin \frac{\theta}{2}$$\cos \frac{\theta}{2}$$\tan \frac{\theta}{2}$$\cos \theta=\frac{3}{5}$$0&lt;\theta&lt;\frac{\pi}{2}$$\cos\theta=\dfrac{3}{5}$$0&lt;\theta&lt;\dfrac{\pi}{2}$$\theta$$$\sin\theta = \pm \sq…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 26 Oct 2024 18:54:40 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 Exercise 8.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-2-p3</link>
            <description>Question 5 Exercise 8.2

Solutions of Question 5 of Exercise 8.2 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\sin \theta$$\cos \theta$$\tan \theta$$\sin 2 \theta=\frac{24}{25}, 2 \theta$$\sin 2\theta=\dfrac{24}{25}$$2\theta$$$\cos 2\theta = \pm \sqrt{1-\sin^2 2\theta}$$$2\theta$$\cos 2\theta$\begin{align*}\cos 2\theta &amp; = - \sqrt{1-\sin^2 2\theta}\\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 26 Oct 2024 18:54:42 +0000</pubDate>
        </item>
        <item>
            <title>Question 6 Exercise 8.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-2-p4</link>
            <description>Question 6 Exercise 8.2

Solutions of Question 6 of Exercise 8.2 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\sin 15^{\circ} \cos 15^{\circ}$$$\sin 2 \theta = 2\sin\theta \cos\theta$$$$\sin\theta \cos\theta = \frac{1}{2}\sin 2\theta$$$\theta = 15^{\circ}$\begin{align*}
\sin 15^{\circ} \cos 15^{\circ} &amp; = \frac{1}{2}\sin 2(15^{\circ}) \\
&amp; \frac{1}{2…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 26 Oct 2024 18:54:45 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 Exercise 8.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-2-p5</link>
            <description>Question 7 Exercise 8.2

Solutions of Question 7 of Exercise 8.2 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $$\sin ^{2} \alpha \cos ^{2} \alpha$$\begin{align*}
\sin ^{2} \alpha \cos ^{2} \alpha &amp;= \left(\frac{1-\cos 2\alpha}{2} \right)\left(\frac{1+\cos 2\alpha}{2} \right)\\
&amp;= \frac{1}{4}(1-\cos^2 2\alpha) \\
&amp;=\frac{1}{4}\left(1-\frac{1+\cos 4\alp…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 26 Oct 2024 18:54:47 +0000</pubDate>
        </item>
        <item>
            <title>Question 8(i, ii &amp; iii) Exercise 8.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-2-p6</link>
            <description>Question 8(i, ii &amp; iii) Exercise 8.2

Solutions of Question 8(i, ii &amp; iii) of Exercise 8.2 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $(\sin \theta+\cos \theta)^{2}=1+\sin 2 \theta$\begin{align*}
LHS &amp; = (\sin \theta+\cos \theta)^{2} \\
&amp;=\sin^2\theta + \cos^2\theta +2\sin \theta \cos\theta\\
&amp;= 1+2\sin \theta \cos\theta \quad (\because \sin^2\theta…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 26 Oct 2024 18:54:48 +0000</pubDate>
        </item>
        <item>
            <title>Question 8(iv, v &amp; vi) Exercise 8.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-2-p7</link>
            <description>Question 8(iv, v &amp; vi) Exercise 8.2

Solutions of Question 8(iv, v &amp; vi) of Exercise 8.2 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\csc 2 \alpha=\dfrac{\tan \alpha+\cot \alpha}{2}$\begin{align*}
RHS &amp; = \dfrac{\tan \alpha+\cot \alpha}{2} \\
&amp; = \dfrac{1}{2}\left(\frac{\sin\alpha}{\cos\alpha}+\frac{\cos\alpha}{\sin\alpha} \right)\\
\end{align*}$8 \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 26 Oct 2024 18:54:50 +0000</pubDate>
        </item>
        <item>
            <title>Question 8(vii, viii &amp; ix) Exercise 8.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-2-p8</link>
            <description>Question 8(vii, viii &amp; ix) Exercise 8.2

Solutions of Question 8(vii, viii &amp; ix) of Exercise 8.2 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\sin 2 \theta=2 \cot \theta \sin ^{2} \theta$\begin{align*}
RHS &amp;= 2 \cot \theta \sin ^{2} \theta\\
&amp;= 2 \frac{\cos \theta }{\sin \theta} \sin ^{2} \theta\\
&amp;= 2 \cos \theta \sin\theta\\
&amp;=  \sin2 \theta\\
&amp;=LH…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 26 Oct 2024 18:54:53 +0000</pubDate>
        </item>
        <item>
            <title>Question 8(x, xi &amp; xii) Exercise 8.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-2-p9</link>
            <description>Question 8(x, xi &amp; xii) Exercise 8.2

Solutions of Question 8(x, xi &amp; xii) of Exercise 8.2 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\sec 2 x=\dfrac{\cos x}{\cos x+\sin x}+\dfrac{\sin x}{\cos x-\sin x}$\begin{align*}
RHS &amp;= \dfrac{\cos x}{\cos x+\sin x}+\dfrac{\sin x}{\cos x-\sin x}\\
&amp;=\dfrac{\cos x(\cos x-\sin x)+\sin x(\cos x+\sin x)}{(\cos x+\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 26 Oct 2024 18:54:54 +0000</pubDate>
        </item>
        <item>
            <title>Question 8(xiii, xiv &amp; xv)  Exercise 8.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-2-p10</link>
            <description>Question 8(xiii, xiv &amp; xv)  Exercise 8.2

Solutions of Question 8(xiii, xiv &amp; xv) of Exercise 8.2 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\csc 2 \alpha-\cot 2 \alpha=\tan \alpha$\begin{align*}
LHS &amp;= \csc 2 \alpha-\cot 2 \alpha\\
&amp;=\frac{1}{\sin 2 \alpha}- \frac{\cos2 \alpha}{\sin 2\alpha }\\
&amp;=\frac{1-\cos2 \alpha}{\sin2 \alpha}\\
&amp;= \frac{2\si…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 26 Oct 2024 18:56:27 +0000</pubDate>
        </item>
        <item>
            <title>Question 8(xvi, xvii &amp; xviii)  Exercise 8.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-2-p11</link>
            <description>Question 8(xvi, xvii &amp; xviii)  Exercise 8.2

Solutions of Question 8(xvi, xvii &amp; xviii) of Exercise 8.2 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\dfrac{1-\cos ^{2} \beta}{2-2 \cos \beta}=\cos ^{2} \dfrac{\beta}{2}$\begin{align*}
LHS &amp;= \dfrac{1-\cos ^{2} \beta}{2-2 \cos \beta}\\
&amp;= \dfrac{\sin ^{2} \beta}{2-2 \cos \beta}\\
&amp;=\dfrac{4\sin ^{2} \fr…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 26 Oct 2024 18:56:02 +0000</pubDate>
        </item>
        <item>
            <title>Question 8(xix, xx, xxi &amp; xxii)  Exercise 8.2</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-2-p12</link>
            <description>Question 8(xix, xx, xxi &amp; xxii)  Exercise 8.2

Solutions of Question 8(xix, xx, xxi &amp; xxii) of Exercise 8.2 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $$\frac{\sin 2 \alpha}{\sin \alpha}-\frac{\cos 2 \alpha}{\cos \alpha}=\sec \alpha$$\begin{align*}
LHS &amp;= \dfrac{\sin 2 \alpha}{\sin \alpha}-\frac{\cos 2 \alpha}{\cos \alpha}\\
&amp;= \dfrac{\sin 2 \alpha …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 26 Oct 2024 18:54:46 +0000</pubDate>
        </item>
        <item>
            <title>Question 1(i, ii, iii &amp; iv)  Exercise 8.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-3-p1</link>
            <description>Question 1(i, ii, iii &amp; iv)  Exercise 8.3

Solutions of Question 1(i, ii, iii &amp; iv) of Exercise 8.3 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $$4 \sin 16x \cos 10x $$\begin{align*}
&amp;4 \sin 16x \cos 10x \\
&amp; = 2 (2\sin 16x \cos 10x) \\
&amp;= 2[\sin(16x+10x)+\sin(16x-10x)]\\
&amp;= 2[\sin (26x)+\sin(6x)]
\end{align*}$10 \cos 10y \cos 6y$\begin{align*}
&amp;10 \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 28 Oct 2024 17:14:30 +0000</pubDate>
        </item>
        <item>
            <title>Question 1(v, vi, vii &amp; viii) Exercise 8.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-3-p2</link>
            <description>Question 1(v, vi, vii &amp; viii) Exercise 8.3

Solutions of Question 1(v, vi, vii &amp; viii) of Exercise 8.3 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $ \sin(-u) \sin 5u$\begin{align*}
&amp;\sin(-u) \sin 5u \\
=&amp; -\sin u \sin 5u \\
=&amp; -\frac{1}{2}[\cos(u - 5u) - \cos(u + 5u)] \\
= &amp;-\frac{1}{2}[\cos(-4u) - \cos(6u)] \\
=&amp; \frac{1}{2}[\cos(6u) - \cos(4u) ]
\e…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 28 Oct 2024 17:14:29 +0000</pubDate>
        </item>
        <item>
            <title>Question 1(ix, x &amp; xi) Exercise 8.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-3-p3</link>
            <description>Question 1(ix, x &amp; xi) Exercise 8.3

Solutions of Question 1(ix, x &amp; xi) of Exercise 8.3 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $2 \sin 75{\circ} \sin 15{\circ}$\begin{align*}
&amp;\quad2 \sin 75^{\circ} \sin 15^{\circ} \\
&amp;= \cos(75^{\circ} - 15^{\circ}) - \cos(75^{\circ} + 15^{\circ}) \\
&amp;= \cos 60^{\circ} - \cos 90^{\circ} \\
\end{align*}$4 \sin …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 28 Oct 2024 17:14:30 +0000</pubDate>
        </item>
        <item>
            <title>Question 2(i, ii, iii, iv and v) Exercise 8.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-3-p4</link>
            <description>Question 2(i, ii, iii, iv and v) Exercise 8.3

Solutions of Question 2(i, ii, iii, iv and v) of Exercise 8.3 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\sin 70^{\circ} + \sin 30^{\circ}$\begin{align*}
 &amp; \quad \sin 70^{\circ} + \sin 30^{\circ} \\
&amp; = 2 \sin \left(\frac{70+30}{2} \right) \cos \left(\frac{70-30}{2} \right) \\
&amp; = 2 \sin \left(\frac{1…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 28 Oct 2024 17:14:31 +0000</pubDate>
        </item>
        <item>
            <title>Question 3(i, ii, iii, iv &amp; v) Exercise 8.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-3-p5</link>
            <description>Question 3(i, ii, iii, iv &amp; v) Exercise 8.3

Solutions of Question 3(i, ii, iii, iv &amp; v) of Exercise 8.3 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\dfrac{\cos (\alpha + \beta)}{\cos(\alpha - \beta)}=\dfrac{1- \tan \alpha \tan \beta}{1+ \tan \alpha \tan \beta}$\begin{align*}
RHS &amp; = \dfrac{1- \tan \alpha \tan \beta}{1+ \tan \alpha \tan \beta} \\
&amp; …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 28 Oct 2024 17:14:31 +0000</pubDate>
        </item>
        <item>
            <title>Question 3(vi, vii, viii, ix &amp; x) Exercise 8.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-3-p6</link>
            <description>Question 3(vi, vii, viii, ix &amp; x) Exercise 8.3

Solutions of Question 3(vi, vii, viii, ix &amp; x) of Exercise 8.3 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $2\tan y \cos 3y= \sec y(\sin 4y-\sin 2y)$\begin{align*}
LHS &amp; = 2\tan y \cos 3y \\
&amp; = 2 \cdot \frac{\sin y}{\cos y} \cos 3y \\
&amp; = \sec y (2 \cos 3y \sin y) \\
&amp; = \sec y \left(\sin (3y+y)-\sin (…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 28 Oct 2024 17:14:32 +0000</pubDate>
        </item>
        <item>
            <title>Question 3(xi, xii &amp; xiii) Exercise 8.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-3-p7</link>
            <description>Question 3(xi, xii &amp; xiii) Exercise 8.3

Solutions of Question 3(xi, xii &amp; xiii) of Exercise 8.3 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $2\cos2u \cos u-\sin 2u \sin u=2\cos^3 u$\begin{align*}
LHS &amp; = 2\cos 2u \cos u - \sin 2u \sin u \\
&amp; = 2\left(\cos^2 u - \sin^2 u\right) \cos u - 2\sin u \cos u \sin u \\
&amp; = 2\cos^3 u - 2\sin^2 u \cos u \\
&amp; =…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 28 Oct 2024 17:14:32 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 Exercise 8.3</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/ex8-3-p8</link>
            <description>Question 4 Exercise 8.3

Solutions of Question 4 of Exercise 8.3 of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\cos 80^{\circ} \cos 60^{\circ} \cos 40^{\circ} \cos 20^{\circ}=\dfrac{1}{16}$\begin{align*}
LHS &amp;= \cos 80^\circ \cos 60^\circ \cos 40^\circ \cos 20^\circ \\
&amp;= \cos 80^\circ \left(\frac{1}{2}\right) \cos 40^\circ \cos 20^\circ \\
&amp;= \frac{1…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 28 Oct 2024 17:14:33 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/re-ex-p1</link>
            <description>Question 1, Review Exercise

Solutions of Question 1 of Review Exercise of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\sin \left(45^{\circ}-30^{\circ}\right)=\ldots$$\frac{\sqrt{6}-\sqrt{2}}{4}$$\frac{\sqrt{6}+\sqrt{2}}{4}$$\frac{\sqrt{6}-\sqrt{2}}{2}$$\frac{\sqrt{3}-\sqrt{2}}{2}$$\frac{\sqrt{6}-\sqrt{2}}{4}$$\tan \left(\frac{\pi}{6}+\frac{\pi}{4}\rig…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 09 Nov 2024 17:48:41 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/re-ex-p2</link>
            <description>Question 2, Review Exercise

Solutions of Question 2 of Review Exercise of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\sin \theta=\dfrac{3}{5}, \sin \phi=\dfrac{5}{13}$$\theta$$\phi$$\sin (\theta-\phi)$$\sin \theta=\dfrac{3}{5}$$\sin \phi=\dfrac{5}{13}$$\theta$$\phi$\begin{align*}
\cos^2 \theta &amp;= 1-\sin^2\theta\\
&amp;= 1-\left(\frac{3}{5}\right)^2\\
&amp; =…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 09 Nov 2024 18:31:57 +0000</pubDate>
        </item>
        <item>
            <title>Question 3, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/re-ex-p3</link>
            <description>Question 3, Review Exercise

Solutions of Question 3 of Review Exercise of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\frac{1}{\sqrt{2}}(\sin \beta+\cos \beta)$\begin{align*}
&amp;\frac{1}{\sqrt{2}}(\sin \beta+\cos \beta)\\
=&amp; \sin \frac{\pi}{4}\sin \beta+\cos \frac{\pi}{4}\cos \beta\\
=&amp; \cos(\beta -\frac{\pi}{4})
\end{align*}$\frac{1}{\sqrt{2}} \sin 75^…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 09 Nov 2024 18:32:33 +0000</pubDate>
        </item>
        <item>
            <title>Question 4, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/re-ex-p4</link>
            <description>Question 4, Review Exercise

Solutions of Question 4 of Review Exercise of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\dfrac{1+\tan 15^{\circ}}{1-\tan 15^{\circ}}$\begin{align*}
&amp;\frac{1+\tan 15^{\circ}}{1-\tan 15^{\circ}}\\
=&amp;\frac{1+\tan 15^{\circ}}{1-1 \cdot \tan 15^{\circ}}\\
=&amp;\frac{\tan 45^{\circ} + \tan 15^{\circ}}{1 - \tan 45^{\circ} \tan 15^{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 09 Nov 2024 18:33:14 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 and 6, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/re-ex-p5</link>
            <description>Question 5 and 6, Review Exercise

Solutions of Question 5 and 6 of Review Exercise of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\tan \theta$$\tan \left(\theta-45^{\circ}\right)=\frac{1}{3}$\begin{align*}
&amp; \frac{\tan \theta - \tan 45^{\circ}}{1 + \tan \theta \cdot \tan 45^{\circ}} =\frac{1}{3}\\
\implies &amp; \frac{\tan \theta - 1}{1 + \tan \theta}= \f…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 09 Nov 2024 18:44:48 +0000</pubDate>
        </item>
        <item>
            <title>Question 7, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/re-ex-p6</link>
            <description>Question 7, Review Exercise

Solutions of Question 7 of Review Exercise of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\dfrac{4 \sin ^{2} \theta \cos \theta}{\cos 3 \theta+\cos \theta}=\tan 2 \theta \tan \theta$\begin{align*}
LHS&amp;=\frac{4 \sin^2 \theta \cos \theta}{\cos 3 \theta + \cos \theta}\\
&amp;=\frac{4 \sin \theta\sin \theta \cos \theta}{4\cos^ 3 \t…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 09 Nov 2024 18:47:22 +0000</pubDate>
        </item>
        <item>
            <title>Question 8, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/re-ex-p7</link>
            <description>Question 8, Review Exercise

Solutions of Question 8 of Review Exercise of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $$\sqrt{\frac{\cos \left(90^{\circ}+x\right) \sec (-x) \tan \left(180^{\circ}-x\right)}{\sec \left(360^{\circ}-x\right) \sin \left(180^{\circ}+x\right) \cot \left(90^{\circ}-x\right)}}=i .$$\begin{align*}
LHS&amp;= \sqrt{\frac{\cos \left(90…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 09 Nov 2024 18:47:40 +0000</pubDate>
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        <item>
            <title>Question 9, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/re-ex-p8</link>
            <description>Question 9, Review Exercise

Solutions of Question 9 of Review Exercise of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $$\sqrt{\frac{\left(1-\tan ^{2} x \cos (-x) \cos \left(360^{\circ}-x\right)\right) \tan 45^{\circ}}{\left\{\sin 90^{\circ}-\sin \left(180^{\circ}+x\right)\right\}\left\{\sin 90^{\circ}-\cos \left(90^{\circ}-x\right)\right\}}}$$\begin{al…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 09 Nov 2024 18:49:13 +0000</pubDate>
        </item>
        <item>
            <title>Question 10, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit08/re-ex-p9</link>
            <description>Question 10, Review Exercise

Solutions of Question 10 of Review Exercise of Unit 08: Fundamental of Trigonometry. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\sin (16 x)=16 \sin (x) \cos (x) \cos (2 x) \cos (4 x) \cos (8 x)$\begin{align*}
RHS&amp;=16 \sin (x) \cos (x) \cos (2 x) \cos (4 x) \cos (8 x) \\
&amp;= 8(2 \sin (x) \cos (x) )\cos (2 x) \cos (4 x) \cos (8 x) \\
&amp;=  8 \sin2 (x) \cos (2 x) \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 09 Nov 2024 18:51:06 +0000</pubDate>
        </item>
        <item>
            <title>Question 1, Exercise 9.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit09/ex9-1-p1</link>
            <description>Question 1, Exercise 9.1

Solutions of Question 1 of Exercise 9.1 of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $y=2-2 \operatorname{Cos} \theta$\begin{align*} -1 \leq \operatorname{Cos} \theta \leq 1 \end{align*}$-2$\begin{align*} &amp; 2 \geq -2 \operatorname{Cos} \theta \geq -2 \end{align*}$2$\begin{align*}
 &amp; 4 \geq 2-2 \operatorname{Cos} \theta \geq 0 \\
…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 27 Nov 2024 15:59:09 +0000</pubDate>
        </item>
        <item>
            <title>Question 2, Exercise 9.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit09/ex9-1-p2</link>
            <description>Question 2, Exercise 9.1

Solutions of Question 2 of Exercise 9.1 of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $y=\dfrac{1}{4+3 \operatorname{Sin} \theta}$\begin{align*} -1 \leq \operatorname{Sin} \theta \leq 1 \end{align*}$3$\begin{align*}  -3 \leq 3 \operatorname{Sin} \theta \leq 3 \end{align*}$4$\begin{align*}
 &amp; 1 \leq 4+3 \operatorname{Sin} \theta \l…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 27 Nov 2024 15:59:10 +0000</pubDate>
        </item>
        <item>
            <title>Question 3, Exercise 9.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit09/ex9-1-p3</link>
            <description>Question 3, Exercise 9.1

Solutions of Question 3 of Exercise 9.1 of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $y=7 \cos 4x$\begin{align*} 
&amp; -1\leq \cos 4x \leq 1 \,\, \forall \,\, x\in \mathbb{R} \\
\implies &amp; -7\leq 7 \cos 4x \leq 7 \\
\end{align*}$= ]-\infty, \infty[ = \mathbb{R}$$=[-7,7]$$y=\cos \frac{x}{3}$\begin{align*} 
&amp; -1\leq \cos \frac{x}{3} \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 27 Nov 2024 15:59:11 +0000</pubDate>
        </item>
        <item>
            <title>Question 4(i-iv), Exercise 9.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit09/ex9-1-p4</link>
            <description>Question 4(i-iv), Exercise 9.1

Solutions of Question 4(i-iv) of Exercise 9.1 of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $y=\sin x+x \cdot \cos x$$f(x)=\sin x+x \cdot \cos x$\begin{align*} f(-x)  = \sin (-x) + (-x)\cdot \cos (-x) \end{align*}$\sin(-x)=-\sin x$$\cos (-x) = \cos x$\begin{align*}
f(x) &amp; = -\sin x - x \cdot \cos x \\
&amp; = -(\sin x + x \cdot …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 27 Nov 2024 15:59:11 +0000</pubDate>
        </item>
        <item>
            <title>Question 4(v-viii), Exercise 9.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit09/ex9-1-p5</link>
            <description>Question 4(v-viii), Exercise 9.1

Solutions of Question 4(v-viii) of Exercise 9.1 of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $y=\dfrac{\sin ^{2} x}{x+\tan x}$\[y = \frac{\sin^2 x}{x + \tan x}\]\begin{align*}
y(-x) &amp;= \frac{\big(-\sin x\big)^2}{-x - \tan x} \\
&amp;= \frac{\sin^2 x}{-x - \tan x}\\
&amp; = \frac{\sin^2 x}{-(x + \tan x)}\\
&amp; = -\frac{\sin^2 x}{x +…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 27 Nov 2024 15:59:12 +0000</pubDate>
        </item>
        <item>
            <title>Question 5(i-v), Exercise 9.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit09/ex9-1-p6</link>
            <description>Question 5(i-v), Exercise 9.1

Solutions of Question 5(i-v) of Exercise 9.1 of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $y=2 \operatorname{Sin} x$$y=2 \operatorname{Cos} 3 x$$y=2 \operatorname{Tan} 2 x$$\mathrm{y}=\operatorname{Cos} \frac{\mathrm{x}}{2}$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 27 Nov 2024 15:59:13 +0000</pubDate>
        </item>
        <item>
            <title>Question 5(vi-x), Exercise 9.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit09/ex9-1-p7</link>
            <description>Question 5(vi-x), Exercise 9.1

Solutions of Question 5(vi-x) of Exercise 9.1 of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $y=2 \operatorname{Sin} 3 x$$y=3 \operatorname{Cos} x$$y=\operatorname{Cos}^{2} x$$y=\operatorname{Sin}^{2} x$$y=\operatorname{Tan}^{2} x$$y=\operatorname{Sin} \frac{x}{2}$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 27 Nov 2024 15:59:14 +0000</pubDate>
        </item>
        <item>
            <title>Question 6, Exercise 9.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit09/ex9-1-p8</link>
            <description>Question 6, Exercise 9.1

Solutions of Question 6 of Exercise 9.1 of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $y=6 \sec(2 x-3)$$\sec$$2\pi$\begin{align*}
6 \sec(2 x-3) &amp; = 6 \sec(2 x-3+2\pi) \\
&amp; = 6 \sec(2(x+\pi)-3)
\end{align*}$6 \sec(2 x-3)$$\pi$$y=\cos (5 x+4)$$\cos$$2\pi$\begin{align*}
\cos (5 x+4) &amp; = 6 \cos(5x+4+2\pi) \\
&amp; = \cos\left(5\left(x+\fr…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 27 Nov 2024 15:59:15 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 &amp; 8, Exercise 9.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit09/ex9-1-p9</link>
            <description>Question 7 &amp; 8, Exercise 9.1

Solutions of Question 7 &amp; 8 of Exercise 9.1 of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $y=\operatorname{Sin} x$$y=\operatorname{Sin} 2 x$$[0,2 \pi]$$y=\operatorname{Cos} x$$y=\operatorname{Cos} 2 x$$[0,2 \pi]$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 27 Nov 2024 15:59:15 +0000</pubDate>
        </item>
        <item>
            <title>Question 9, Exercise 9.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit09/ex9-1-p10</link>
            <description>Question 9, Exercise 9.1

Solutions of Question 9 of Exercise 9.1 of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\sin x=\cos x$$\cos x=x$$\sin x=x$$\tan x=x$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 27 Nov 2024 15:59:09 +0000</pubDate>
        </item>
        <item>
            <title>Question 10, Exercise 9.1</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit09/ex9-1-p11</link>
            <description>Question 10, Exercise 9.1

Solutions of Question 10 of Exercise 9.1 of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $ V(t)=a \operatorname{Sin}(k(t-d))+c$$56 \mathrm{~Hz} A C$$k$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 27 Nov 2024 15:59:10 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 and 3,Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit09/re-ex-1-p2</link>
            <description>Question 2 and 3,Review Exercise

Solutions of Question 2 and 3 of Review Exercise of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 27 Nov 2024 15:59:17 +0000</pubDate>
        </item>
        <item>
            <title>Question 4, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit09/re-ex-1-p3</link>
            <description>Question 4, Review Exercise

Solutions of Question 4 of Review Exercise of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 27 Nov 2024 15:59:18 +0000</pubDate>
        </item>
        <item>
            <title>Question 1,Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit09/re-ex-p1</link>
            <description>Question 1,Review Exercise

Solutions of Question 1 of Review Exercise of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\cos \theta=\frac{\sqrt{3}}{2}$$\sin \theta=$$\frac{1}{2}$$-\frac{1}{2}$$\sqrt{3}$$-\frac{2}{\sqrt{3}}$$-\frac{1}{2}$$\tan (-15 \pi)=$$ 0$$-1$$1$$0$$2 \sin \theta+\frac{1}{2}cosec \theta \theta $$\theta=45^{\circ}$$\frac{1}{\sqrt{2}}$$\frac…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 27 Nov 2024 15:59:18 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 and 3, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit09/re-ex-p2</link>
            <description>Question 2 and 3, Review Exercise

Solutions of Question 2 and 3 of Review Exercise of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\cos \theta -\sin \theta=\sqrt{2}\sin \theta,$$\cos \theta+ \sin \theta=\sqrt{2} \cos \theta$$$\cos \theta -\sin \theta=\sqrt{2}\sin \theta$$\begin{align*}
&amp; \cos \theta=\sqrt{2}\sin \theta + \sin \theta \\
\implies &amp; \cos \the…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 27 Nov 2024 16:04:15 +0000</pubDate>
        </item>
        <item>
            <title>Question 4, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit09/re-ex-p3</link>
            <description>Question 4, Review Exercise

Solutions of Question 4 of Review Exercise of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 27 Nov 2024 15:59:20 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 and 6, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit09/re-ex-p4</link>
            <description>Question 5 and 6, Review Exercise

Solutions of Question 5 and 6 of Review Exercise of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 27 Nov 2024 15:59:22 +0000</pubDate>
        </item>
        <item>
            <title>Question 7, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit09/re-ex-p5</link>
            <description>Question 7, Review Exercise

Solutions of Question 7 of Review Exercise of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 27 Nov 2024 15:59:22 +0000</pubDate>
        </item>
        <item>
            <title>Question 8, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit09/re-ex-p6</link>
            <description>Question 8, Review Exercise

Solutions of Question 8 of Review Exercise of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 27 Nov 2024 15:59:23 +0000</pubDate>
        </item>
        <item>
            <title>Question 9, Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit09/re-ex-p7</link>
            <description>Question 9, Review Exercise

Solutions of Question 9 of Review Exercise of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 27 Nov 2024 15:59:23 +0000</pubDate>
        </item>
        <item>
            <title>Question 10(i-v), Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit09/re-ex-p8</link>
            <description>Question 10(i-v), Review Exercise

Solutions of Question 10(i-v) of Review Exercise of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 27 Nov 2024 15:59:24 +0000</pubDate>
        </item>
        <item>
            <title>Question 10(vi-x), Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit09/re-ex-p9</link>
            <description>Question 10(vi-x), Review Exercise

Solutions of Question 10(vi-x) of Review Exercise of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 27 Nov 2024 15:59:24 +0000</pubDate>
        </item>
        <item>
            <title>Question 10(xi-xv), Review Exercise</title>
            <link>https://www.mathcity.org/math-11-nbf/sol/unit09/re-ex-p10</link>
            <description>Question 10(xi-xv), Review Exercise

Solutions of Question 10(xi-xv) of Review Exercise of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 27 Nov 2024 15:59:19 +0000</pubDate>
        </item>
        <item>
            <title>FSc/ICS Part 2 (Mathematics): PTB</title>
            <link>https://www.mathcity.org/fsc-part2-ptb</link>
            <description>FSc/ICS Part 2 (Mathematics): PTB

[Calculus and Analytic Geometry, MATHEMATICS 12]
Calculus and Analytic Geometry, MATHEMATICS 12 (Mathematics FSc/ICS Part 2 or HSSC-II), Punjab Textbook Board (PTB) Lahore, Pakistan. There are total seven (7) units in this book.
One this page we have posted Notes (Solutions), MCQs, short question, sample papers and old papers related to this subject. This book has wide scope and it is part of syllabus of Mathematics in FSc/ICS from all board (Board of Intermedi…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 22 Sep 2024 08:59:48 +0000</pubDate>
        </item>
        <item>
            <title>Report Abuse</title>
            <link>https://www.mathcity.org/report_abuse</link>
            <description>Report Abuse


All the resources published/posted on MathCity.org are sent by different people to help the other people for the promotion of mathematics. These are open educational resources (OER).

OER are teaching, learning, and research resources that reside in the public domain or have been released under an intellectual property license that permits their free use or re-purposing by others. Open educational resources include full courses, course materials, modules, textbooks, streaming vide…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:39:42 +0000</pubDate>
        </item>
        <item>
            <title>Short Term Preparation FSc/ICS 1</title>
            <link>https://www.mathcity.org/fsc-part1-ptb/short-term-preparation-salman-sherazi</link>
            <description>Short Term Preparation FSc/ICS 1

fsc fsc_part1 m_salman_sherazi important_questions_fsc_1

[Short Term Preparation by M Salman Sherazi]
This document contains all the important MCQs, Short Questions and Long Questions of Mathematics HSSC-I (FSc/ICS Part 1) from the Textbook of Algebra and Trigonometry for Class XI. It has been done to help the students and teachers at no cost by $\sqrt{2}$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 02 May 2024 17:12:17 +0000</pubDate>
        </item>
        <item>
            <title>Definitions: FSc Part 2 (Mathematics): PTB</title>
            <link>https://www.mathcity.org/fsc-part2-ptb/definitions</link>
            <description>Definitions: FSc Part 2 (Mathematics): PTB

On this page, all the definitions of “Calculus and Analytic Geometry, MATHEMATICS 12” (Mathematics FSc Part 2 or HSSC-II), Punjab Textbook Board (PTB) Lahore, Pakistan are given. We are very thankful to $A=x^2$$f:X\to Y$$X$$f:X\to Y$$y$$Y$$y=ax+b$$x$$y$$f(x)=2x-6$$p(x) = {a_n}{x^n} + {a_{n - 1}}{x^{n - 1}} + {a_{n - 2}}{x^{n - 2}} + ... + {a_1}x + {a_0}$${a_0},\,{a_1},\,{a_2},...,{a_n}$$f(x)=ax+b$$X$$I:X\to X$$X$$Y$$C:X \rightarrow Y$$C(x)=a$$x \in X$$…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 20 Oct 2024 18:16:52 +0000</pubDate>
        </item>
        <item>
            <title>Definitions: Mathematics 12: PTB by Muzzammil Subhan</title>
            <link>https://www.mathcity.org/fsc-part2-ptb/definitions-muzzammil-subhan</link>
            <description>Definitions: Mathematics 12: PTB by Muzzammil Subhan

Definitions from Calculus and Analytic Geometry, MATHEMATICS 12, published by Punjab Textbook Board (PTB) Lahore, Pakistan. We are very thankful to Muzzammil Subhan for his valuable contribution. Download or view PDF for all definitions. Samples is given below$P(x)=a_0 x^0+a_1 x^1+a_2 x^2+\ldots . .+a_{n-1} x^{n-1}+a_n x^n$$n \in W$$a_0, a_1, a_2, \ldots, a_n \in R$$f(x)=a x+b$$a, b \in R$$a \neq 0$$f(x)=x$$f(x)=c$$c \in R$$\frac{P(x)}{Q(x)}$…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 20 Oct 2024 18:16:28 +0000</pubDate>
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        <item>
            <title>Important Questions: HSSC-II</title>
            <link>https://www.mathcity.org/fsc-part2-ptb/important-questions</link>
            <description>Important Questions: HSSC-II

These questions are taken from old papers for the book Calculus and Analytic Geometry, MATHEMATICS 12 (Mathematics FSc Part 2 or HSSC-II), Punjab Textbook Board (PTB) Lahore, Pakistan.

	*  Unit 01: Functions and Limits

	*  Unit 02: Differentiation

	*  Unit 03: Integration

	*  Unit 04: Introduction to Analytic Geometry

	*  Unit 05: Linear Inequalities and Linear Programming

	*</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 18 Apr 2024 08:02:52 +0000</pubDate>
        </item>
        <item>
            <title>Subjective Mathematics 12th by Muhammad Shahbaz</title>
            <link>https://www.mathcity.org/fsc-part2-ptb/subjective-mathematics-m-shahbaz</link>
            <description>Subjective Mathematics 12th by Muhammad Shahbaz

[Subjective Mathematics 12th by Muhammad Shahbaz]
These handwritten notes are sent by Muhammad Shahbaz. We are very thankful to him for sending these notes. These notes are based on the book “Calculus and Analytic Geometry, MATHEMATICS 12 (Mathematics FSc/ICS Part 2 or HSSC-II), Punjab Textbook Board (PTB) Lahore, Pakistan.&#039;&#039; There are total seven (7) units in this book.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 23 Sep 2025 19:59:04 +0000</pubDate>
        </item>
        <item>
            <title>Solutions: Math 9th PCTB</title>
            <link>https://www.mathcity.org/math-9th-pctb/sol</link>
            <description>Solutions: Math 9th PCTB

[Solutions of Mathematics 9th PCTB]
Notes (Solutions) of Mathematics 9 (Mathematics for Matric), Punjab Curriculum and Textbook Board (PCTB) Lahore.
Our aim here is to provides clear and step-by-step solutions for mathematical concepts, including real numbers, logarithms, algebra, trigonometry, and probability. we will try our best to complete the solutions as soon as possible for teachers and students. To download a book, please</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 04 May 2026 16:21:21 +0000</pubDate>
        </item>
        <item>
            <title>FSC/ICS Part 1 Math Solution (11th Class) – Punjab Board Solved Exercises</title>
            <link>https://www.mathcity.org/math-11-pectaa/sol</link>
            <description>FSC/ICS Part 1 Math Solution (11th Class) – Punjab Board Solved Exercises

[FSC ICS Part 1 Math Solution (11th Class) – Punjab Board Solved Exercises]
FSC or ICS Part 1 Math Solution (11th Class), Punjab Board Solved Exercises. Mathematics 11 (FSc or ICS Part 1, HSSC-I) is published by Punjab Education, Curriculum, Training and Assessment Authority (PECTAA) Lahore - Pakistan formally know as Punjab Textbook Board (PTB)</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 24 May 2026 10:06:29 +0000</pubDate>
        </item>
        <item>
            <title>General Mathematics 9</title>
            <link>https://www.mathcity.org/matric/9th_general</link>
            <description>General Mathematics 9

[General Mathematics 9th Class]
There are ten chapters in General Mathematics 9 for Punjab Textbook Board, Lahore. Solutions of all the chapters are given below. One can download the PDF file of the notes. Please remember that, to view these notes one must have PDF reader installed in their system. We will try our best to add online view of the notes very soon.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 15 Dec 2025 16:49:07 +0000</pubDate>
        </item>
        <item>
            <title>Mechanics I (Statics) by Dr Babar Ahmad</title>
            <link>https://www.mathcity.org/notes/mechanics-i-statics-dr-babar-ahmad</link>
            <description>Mechanics I (Statics) by Dr Babar Ahmad

[Mechanics I (Statics) by Dr Babar Ahmad]

We are very thankful to Dr Babar Ahmad for sharing his book on MathCity.org. This book is very helpful for undergraduate students of Science and Engineering Programs. 

This book is shared by the permission of the author and he keeps the copyright of the book.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 24 Jul 2023 12:49:29 +0000</pubDate>
        </item>
        <item>
            <title>Mechanics III (Analytic Dynamics II) by Dr Babar Ahmad</title>
            <link>https://www.mathcity.org/notes/mechanics-iii-analytic-dynamics-ii-dr-babar-ahmad</link>
            <description>Mechanics III (Analytic Dynamics II) by Dr Babar Ahmad

[Mechanics III (Analytic Dynamics II) by Dr Babar Ahmad]

We are very thankful to Dr Babar Ahmad for sharing his book on MathCity.org. This book is very helpful for undergraduate students of Science and Engineering Programs. 

This book is shared by the permission of the author and he keeps the copyright of the book.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 10 May 2025 17:33:01 +0000</pubDate>
        </item>
        <item>
            <title>Multivariable Calculus by M Usman Hamid and M Zeeshan Ahmad</title>
            <link>https://www.mathcity.org/notes/multivariable-calculus-m-usman-hamid-and-m-zeeshan-ahmad</link>
            <description>Multivariable Calculus by M Usman Hamid and M Zeeshan Ahmad

[Multivariable Calculus by M Usman Hamid and M Zeeshan Ahmad]
Multivariable calculus is a fundamental subject that extends the concepts of single-variable calculus to higher-dimensional spaces. It provides a powerful framework for analyzing and modeling complex phenomena in fields such as physics,
engineering, economics, and computer science. This textbook is designed to provide a comprehensive introduction to multivariable calculus, c…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 15 Jun 2025 16:25:59 +0000</pubDate>
        </item>
        <item>
            <title>M for Mathodology</title>
            <link>https://www.mathcity.org/people/mformathodology</link>
            <description>M for Mathodology

[M for Mathodology]

We are very thankful to M for Mathodology for providing us notes.

I’m Rabbia Abid – a pure math enthusiast on a mission to transform the way we experience mathematics! Currently pursuing a bachelor’s degree in Mathematics, I’m captivated by the elegance and challenge of pure mathematics. My academic journey is punctuated by exciting math olympiads and a never-ending curiosity for proofs, theorems, and abstract reasoning.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 20 Jun 2025 11:23:21 +0000</pubDate>
        </item>
        <item>
            <title>Unit 1: Complex Numbers (Solutions)</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit01</link>
            <description>Unit 1: Complex Numbers (Solutions)

This is a first unit of the book Mathematics 11 published by Khyber Pakhtunkhwa Textbook Board, Peshawar, Pakistan. On this page we have provided the solutions of the questions.

After reading this unit the students will be able to$z$$z=a+ib$$(a,b)$$a$$b$$i=\sqrt{-1}$$a$$z$$b$$z$$\bar{z} = a —ib$$z=a+ib$$|z| = \sqrt{a^2+b^2}$$z=a+ib$$&#039;+&#039;$$&#039;\times&#039;$$z$$|z|=|-z|=|\bar{z}=|-\bar{z}|$$pz^2+ qz+ r = 0$$p,q,r$$z$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 25 Sep 2023 12:08:05 +0000</pubDate>
        </item>
        <item>
            <title>Unit 10: Trigonometric Identities of Sum and Difference of Angles (Solutions)</title>
            <link>https://www.mathcity.org/fsc-part1-kpk/sol/unit10</link>
            <description>Unit 10: Trigonometric Identities of Sum and Difference of Angles (Solutions)

This is a tenth unit of the book Mathematics 11 published by Khyber Pakhtunkhwa Textbook Board, Peshawar, Pakistan. On this page we have provided the solutions of the questions.$a\sin\theta + b\cos \theta$$r\sin(\theta +\psi )$$a = r\cos\psi$$b=r\sin\psi$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 09 Sep 2023 07:00:54 +0000</pubDate>
        </item>
        <item>
            <title>Fill in the blanks by Rauf &amp; Nabeel</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_mcqs/fill_in_the_blanks_by_rauf_nabeel</link>
            <description>Fill in the blanks by Rauf &amp; Nabeel

	*  Fill in the blanks, provided by Adil Rauf &amp; Muhammad Nabil (F.Sc. Part I, Session: 2003-05, FAZMIC Sargodha)
	*  Text Book of Algebra and Trigonometry Class XI (Punjab Textbook Board, Lahore)
 Chapter 02   Download PDF (93KB)</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:46:06 +0000</pubDate>
        </item>
        <item>
            <title>MCQs by Nauman Idrees</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_mcqs/mcqs_by_nauman_idrees</link>
            <description>MCQs by Nauman Idrees

	*  Text Book of Algebra and Trigonometry, Class XI (Punjab Textbook Board, Lahore).

Chapter 01

View Online  | Download PDF (52KB)  | Ch 01: Key

Chapter 02

View Online  | Download PDF (68KB)  | Ch 02: Key

Chapter 03

View Online  | Download PDF (41KB)  | Ch 03: Key

Chapter 04

View Online  | Download PDF (43KB)  | Ch 04: Key

Chapter 05

View Online  | Download PDF (39KB)  |</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:46:06 +0000</pubDate>
        </item>
        <item>
            <title>MCQs-Short Questions by Mr Parvez Khan</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_mcqs/mcqs-short_questions_by_mr._parvez_khan</link>
            <description>MCQs-Short Questions by Mr Parvez Khan

	*  MCQs and Short Question written by Mr. Parvez Khan, composed by Mr. Momin Ali from Text Book of Algebra and Trigonometry Class XI (Punjab Textbook Board, Lahore)
	*  Key to the MCQs is given at page 57.

Erratum
$180^{\circ}$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:46:05 +0000</pubDate>
        </item>
        <item>
            <title>Short Questions by Mr. Akhtar Abbas</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_mcqs/short_questions_by_mr._akhtar_abbas</link>
            <description>Short Questions by Mr. Akhtar Abbas

	*  We are very thankful to Mr. Akhtar Abbas for sharing these short questions.
	*  These short questions are selected from previous 5 years papers of different boards. Solve these at your own to perform well in annual exams.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:46:09 +0000</pubDate>
        </item>
        <item>
            <title>Chapter 01: Number System</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_solutions/ch01</link>
            <description>Chapter 01: Number System

[Chapter 01: Number System]
Notes (Solutions) of Chapter 01: Number System, Textbook of Algebra and Trigonometry Class XI (Mathematics FSc Part 1 or HSSC-I), Punjab Text Book Board, Lahore.

Contents &amp; summary

	*  Rational numbers and irrational numbers$\mathbb{C}$$(x+iy)^n$$\left(\frac{x_1+iy_1}{x_2+iy_2}\right)^n, x_2+iy_2\neq 0$$\sqrt{-1}=i$$\sqrt{-1}$$i$$-i$$i$$-i$$-1$$i^2=-1$$\sqrt{-1}=i$$\sqrt{-1}$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 03 Jun 2023 16:30:31 +0000</pubDate>
        </item>
        <item>
            <title>Chapter 04: Quadratic Equations</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_solutions/ch04</link>
            <description>Chapter 04: Quadratic Equations

[Chapter 04: Quadratic Equations]
Notes (Solutions) of Chapter 04: Quadratic Equations, Text Book of Algebra and Trigonometry Class XI (Mathematics FSc Part 1 or HSSC-I), Punjab Textbook Board, Lahore.

Contents &amp; summary

	*  Introduction
		*  Solutions of Quadratic Equations</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 04 Jun 2023 16:13:15 +0000</pubDate>
        </item>
        <item>
            <title>MCQs by Muhammad Imran Qureshi</title>
            <link>https://www.mathcity.org/fsc/fsc_part_2_mcqs/mcqs_by_muhammad_imran_qureshi</link>
            <description>MCQs by Muhammad Imran Qureshi

	*  Calculus and Analytic Geometry, MATHEMATICS 12 (Punjab Textbook Board, Lahore)
 Unit 01  View Online   Download PDF (78KB)  Unit 01: Key  Unit 02 View Online   Download PDF (71KB)  Unit 02: Key  Unit 03  View Online   Download PDF (67KB)  Unit 03: Key  Unit 04  View Online   Download PDF (50KB)  Unit 04: Key  Unit 05  View Online   Download PDF (49KB)  Unit 05: Key  Unit 06  View Online   Download PDF (58KB)</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:46:42 +0000</pubDate>
        </item>
        <item>
            <title>MCQs by Nauman Idrees</title>
            <link>https://www.mathcity.org/fsc/fsc_part_2_mcqs/mcqs_by_nauman_idrees</link>
            <description>MCQs by Nauman Idrees

	*  Calculus and Analytic Geometry, MATHEMATICS 12 (Punjab Textbook Board, Lahore)
 ARW Unit 01  View Online   Download PDF (48KB)   Unit 01: Key   ARW Unit 02  View Online   Download PDF (62KB)  Unit 02: Key   ARW Unit 03  View Online   Download PDF (72KB)  Unit 03: Key   ARW Unit 04  View Online   Download PDF (48KB)  Unit 04: Key   ARW Unit 05  View Online   Download PDF (52KB)  Unit 05: Key   ARW</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:46:43 +0000</pubDate>
        </item>
        <item>
            <title>MCQs-Short Questions by Mr. Parvez Khan</title>
            <link>https://www.mathcity.org/fsc/fsc_part_2_mcqs/mcqs-short_questions_by_mr._parvez_khan</link>
            <description>MCQs-Short Questions by Mr. Parvez Khan

	*  MCQs and Short Question by Mr. Parvez Khan composed by Momin Ali: Calculus and Analytic Geometry, MATHEMATICS 12 (Punjab Textbook Board, Lahore). Answers are given at page 32.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:46:42 +0000</pubDate>
        </item>
        <item>
            <title>Short Questions by Mr. Akhtar Abbas</title>
            <link>https://www.mathcity.org/fsc/fsc_part_2_mcqs/short_questions_by_mr._akhtar_abbas</link>
            <description>Short Questions by Mr. Akhtar Abbas

	*  We are very thankful to Mr. Akhtar Abbas for sharing these short questions.
	*  These short questions are selected from previous 5 years papers of different boards. Solve these at your own to perform well in annual exams.$\sqrt{x^2-4}$$f(x)=\frac{2x}{x-2}$$x=2$$x^{100}$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:46:47 +0000</pubDate>
        </item>
        <item>
            <title>Unit 01: Complex Numbers (Solutions)</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01</link>
            <description>Unit 01: Complex Numbers (Solutions)

This is a first unit of the book Mathematics 11 published by Khyber Pakhtunkhwa Textbook Board, Peshawar, Pakistan. On this page we have provided the solutions of the questions.

After reading this unit the students will be able to$z$$z=a+ib$$(a,b)$$a$$b$$i=\sqrt{-1}$$a$$z$$b$$z$$\bar{z} = a —ib$$z=a+ib$$|z| = \sqrt{a^2+b^2}$$z=a+ib$$&#039;+&#039;$$&#039;\times&#039;$$z$$|z|=|-z|=|\bar{z}=|-\bar{z}|$$pz^2+ qz+ r = 0$$p,q,r$$z$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:28:42 +0000</pubDate>
        </item>
        <item>
            <title>Unit 02: Matrices and Determinants (Solutions)</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02</link>
            <description>Unit 02: Matrices and Determinants (Solutions)

This is a second unit of the book Mathematics 11 published by Khyber Pakhtunkhwa Textbook Board, Peshawar, Pakistan. On this page we have provided the solutions of the questions.

After reading this unit the students will be able to$z$$z=a+ib$$(a,b)$$a$$b$$i=\sqrt{-1}$$a$$z$$b$$z$$\bar{z} = a —ib$$z=a+ib$$|z| = \sqrt{a^2+b^2}$$z=a+ib$$&#039;+&#039;$$&#039;\times&#039;$$z$$|z|=|-z|=|\bar{z}=|-\bar{z}|$$pz^2+ qz+ r = 0$$p,q,r$$z$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:44:47 +0000</pubDate>
        </item>
        <item>
            <title>Unit 03: Vectors (Solutions)</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03</link>
            <description>Unit 03: Vectors (Solutions)

This is a third unit of the book Mathematics 11 published by Khyber Pakhtunkhwa Textbook Board, Peshawar, Pakistan. On this page we have provided the solutions of the questions.

After reading this unit the students will be able to$i$$j$$i$$j$$k$$O$$-A$$A$$i.i=j.j=k.k=1$$i.j=j.k=k.i=0$$i\times i =j\times j =k\times k=0$$i\times j = k$$j\times k =k\times j = i$$A \times B$$A$$B$$i.j\times k =j.k\times i=k.i\times j=1$$i.k\times j = J.i\times k=k.j\times i=-1$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:11:32 +0000</pubDate>
        </item>
        <item>
            <title>Unit 04: Sequence and Series (Solutions)</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04</link>
            <description>Unit 04: Sequence and Series (Solutions)

This is a forth unit of the book Mathematics 11 published by Khyber Pakhtunkhwa Textbook Board, Peshawar, Pakistan. On this page we have provided the solutions of the questions.

After reading this unit the students will be able to$n$$n$$n$$n$$n$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:30:16 +0000</pubDate>
        </item>
        <item>
            <title>Unit 05: Miscellaneous Series (Solutions)</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05</link>
            <description>Unit 05: Miscellaneous Series (Solutions)

This is a fifth unit of the book Mathematics 11 published by Khyber Pakhtunkhwa Textbook Board, Peshawar, Pakistan. On this page we have provided the solutions of the questions.

After reading this unit the students will be able to$n$$n$$n$$n$$n$$\dfrac{1}{a(a+d)}+\dfrac{1}{(a+d)(a+2 d)}+ \cdots $</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:34:56 +0000</pubDate>
        </item>
        <item>
            <title>Unit 06: Permutation, Combination and Probability (Solutions)</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06</link>
            <description>Unit 06: Permutation, Combination and Probability (Solutions)

This is a sixth unit of the book Mathematics 11 published by Khyber Pakhtunkhwa Textbook Board, Peshawar, Pakistan. On this page we have provided the solutions of the questions.

After reading this unit the students will be able to$n$$n!$$n$$r$$^nP_r$$n$$r$$n$$r$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:34:51 +0000</pubDate>
        </item>
        <item>
            <title>Unit 07: Mathmatical Induction and Binomial Theorem (Solutions)</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07</link>
            <description>Unit 07: Mathmatical Induction and Binomial Theorem (Solutions)

This is a seventh unit of the book Mathematics 11 published by Khyber Pakhtunkhwa Textbook Board, Peshawar, Pakistan. On this page we have provided the solutions of the questions.

After reading this unit the students will be able to$(x+y)^n$$n$$(x+y)^n$$(x+ y)^n.$$(1 +x)^n$$n$$n.$$(l +x)^n$$x$$|x| &lt; 1$$n$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:34:59 +0000</pubDate>
        </item>
        <item>
            <title>Unit 10: Trigonometric Identities of Sum and Difference of Angles (Solutions)</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10</link>
            <description>Unit 10: Trigonometric Identities of Sum and Difference of Angles (Solutions)

This is a tenth unit of the book Mathematics 11 published by Khyber Pakhtunkhwa Textbook Board, Peshawar, Pakistan. On this page we have provided the solutions of the questions.$a\sin\theta + b\cos \theta$$r\sin(\theta +\psi )$$a = r\cos\psi$$b=r\sin\psi$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:44:48 +0000</pubDate>
        </item>
        <item>
            <title>Open MCQs of Mathematics 11</title>
            <link>https://www.mathcity.org/math-11-pectaa/mcqs/open-mcqs-mathematics-11</link>
            <description>Open MCQs of Mathematics 11


[Open MCQs of Mathematics 11]
This is an initial release of the MCQs. The beautiful thing for these notes is that you can edit this booklet. Our aim is to make a database for the high quality MCQs available for all. Please remember these MCQs are related to the book</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 26 Feb 2026 17:44:37 +0000</pubDate>
        </item>
        <item>
            <title>Ch 01: Key</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_mcqs/mcqs_by_nauman_idrees/ch_01_key</link>
            <description>Ch 01: Key

This page include the key to MCQs by Nauman Idrees of Chapter 01.
 1- A  2- A   3- A  4- B   5- C   6- D  6- A   7- D  8- A  9- D  10- C  11- B  12- B  13- C  14- A  15- B  16- A  17- A  18- A  19- A  20- B  21- C   22- D  23- B  24- C  25- A  26- B  27- C  28- B</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:56:40 +0000</pubDate>
        </item>
        <item>
            <title>View</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_mcqs/short_questions_by_mr._akhtar_abbas/view</link>
            <description>View

	*  We are very thankful to Mr. Akhtar Abbas for sharing these short questions. These short questions are selected from previous five years papers of different boards. Solve these at your own to perform well in annual examination. Recommended book for these short questions is “Text Book of Algebra and Trigonometry Class XI (Punjab Textbook Board, Lahore)”. But any student Mathematics can get benefit from it.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:57:20 +0000</pubDate>
        </item>
        <item>
            <title>Ch 01: Number System: Mathematics FSc Part 1</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_solutions/ch01/view</link>
            <description>Ch 01: Number System: Mathematics FSc Part 1

Notes (Solutions) of Chapter 01: Number System, Text Book of Algebra and Trigonometry Class XI (Mathematics FSc Part 1 or HSSC-I), Punjab Textbook Board (PTB), Lahore. There are three exercises in this chapter. Please see the main page of this chapter for MCQs and important question at</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:57:21 +0000</pubDate>
        </item>
        <item>
            <title>Ch 02: Sets, Functions and Groups: Mathematics FSc Part 1</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_solutions/ch02/view</link>
            <description>Ch 02: Sets, Functions and Groups: Mathematics FSc Part 1

Notes (Solutions) of Chapter 02: Sets, Functions and Groups, Text Book of Algebra and Trigonometry Class XI (Mathematics FSc Part 1 or HSSC-I), Punjab Textbook Board (PTB), Lahore. There are eight exercises in this chapter. Please see the main page of this chapter for MCQs and important question at</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:57:28 +0000</pubDate>
        </item>
        <item>
            <title>View Online (Notes of Chapter 04)</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_solutions/ch04/view</link>
            <description>View Online (Notes of Chapter 04)

Notes (Solutions) of Chapter 04: Quadratic Equations, Text Book of Algebra and Trigonometry Class XI (Mathematics FSc Part 1 or HSSC-I), Punjab Textbook Board, Lahore. 

These notes are provided by M. Shahid Nadeem, Lecturer in Mathematics, Punjab College Wah Cantt. One can also download PDF of the notes from this page.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:57:41 +0000</pubDate>
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        <item>
            <title>Ch 05: Partial Fractions: Mathematics FSc Part 1</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_solutions/ch05/view</link>
            <description>Ch 05: Partial Fractions: Mathematics FSc Part 1

Notes (Solutions) of Chapter 05: Partial Fractions, Text Book of Algebra and Trigonometry Class XI (Mathematics FSc Part 1 or HSSC-I), Punjab Textbook Board (PTB), Lahore. There are four exercises in this chapter. Please see the main page of this chapter for MCQs and important question at</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:57:45 +0000</pubDate>
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        <item>
            <title>Ch 06: Sequences and Series: Mathematics FSc Part 1</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_solutions/ch06/view</link>
            <description>Ch 06: Sequences and Series: Mathematics FSc Part 1

Notes (Solutions) of Chapter 06: Sequences and Series, Text Book of Algebra and Trigonometry Class XI (Mathematics FSc Part 1 or HSSC-I), Punjab Textbook Board (PTB), Lahore. There are eleven exercises in this chapter. Please see the main page of this chapter for MCQs and important question at</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:57:49 +0000</pubDate>
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        <item>
            <title>Ch 07: Permutation, Combination and Probability: Mathematics FSc Part 1</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_solutions/ch07/view</link>
            <description>Ch 07: Permutation, Combination and Probability: Mathematics FSc Part 1

Notes (Solutions) of Chapter 07: Permutation, Combination and Probability, Text Book of Algebra and Trigonometry Class XI (Mathematics FSc Part 1 or HSSC-I), Punjab Textbook Board (PTB), Lahore. There are eight exercises in this chapter. Please see the main page of this chapter for MCQs and important question at</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 26 Mar 2022 16:27:34 +0000</pubDate>
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            <title>Ch 08: Mathematical Induction and Binomial Theorem: Mathematics FSc Part 1</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_solutions/ch08/view</link>
            <description>Ch 08: Mathematical Induction and Binomial Theorem: Mathematics FSc Part 1

Notes (Solutions) of Chapter 08: Mathematical Induction and Binomial Theorem, Text Book of Algebra and Trigonometry Class XI (Mathematics FSc Part 1 or HSSC-I), Punjab Textbook Board (PTB), Lahore. There are three exercises in this chapter. Please see the main page of this chapter for MCQs and important question at</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:58:09 +0000</pubDate>
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        <item>
            <title>Ch 09: Fundamentals of Trigonometry: Mathematics FSc Part 1</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_solutions/ch09/view</link>
            <description>Ch 09: Fundamentals of Trigonometry: Mathematics FSc Part 1

Notes (Solutions) of Chapter 09: Fundamentals of Trigonometry, Text Book of Algebra and Trigonometry Class XI (Mathematics FSc Part 1 or HSSC-I), Punjab Textbook Board (PTB), Lahore. There are four exercises in this chapter. Please see the main page of this chapter for MCQs and important question at</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:58:21 +0000</pubDate>
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        <item>
            <title>Ch 10: Trigonometric Identities: Mathematics FSc Part 1</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_solutions/ch10/view</link>
            <description>Ch 10: Trigonometric Identities: Mathematics FSc Part 1

Notes (Solutions) of Chapter 10: Trigonometric Identities, Text Book of Algebra and Trigonometry Class XI (Mathematics FSc Part 1 or HSSC-I), Punjab Textbook Board (PTB), Lahore. There are four exercises in this chapter. Please see the main page of this chapter for MCQs and important question at</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:58:44 +0000</pubDate>
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        <item>
            <title>Ch 12: Application of Trigonometry: Mathematics FSc Part 1</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_solutions/ch12/view</link>
            <description>Ch 12: Application of Trigonometry: Mathematics FSc Part 1

Notes (Solutions) of Chapter 12: Application of Trigonometry, Text Book of Algebra and Trigonometry Class XI (Mathematics FSc Part 1 or HSSC-I), Punjab Textbook Board (PTB), Lahore. There are four exercises in this chapter. Please see the main page of this chapter for MCQs and important question at</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:58:56 +0000</pubDate>
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        <item>
            <title>Ch 13: Inverse Trigonometric Functions: Mathematics FSc Part 1</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_solutions/ch13/view</link>
            <description>Ch 13: Inverse Trigonometric Functions: Mathematics FSc Part 1

Notes (Solutions) of Chapter 10: Inverse Trigonometric Functions, Text Book of Algebra and Trigonometry Class XI (Mathematics FSc Part 1 or HSSC-I), Punjab Textbook Board (PTB), Lahore. There are two exercises in this chapter. Please see the main page of this chapter for MCQs and important question at</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:59:03 +0000</pubDate>
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        <item>
            <title>Ch 14: Solutions of Trigonometric Equation</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_solutions/ch14/view</link>
            <description>Ch 14: Solutions of Trigonometric Equation

Notes (Solutions) of Chapter 14: Solutions of Trigonometric Equation, Text Book of Algebra and Trigonometry Class XI (Mathematics FSc Part 1 or HSSC-I), Punjab Textbook Board (PTB), Lahore. There are four exercises in this chapter. Please see the main page of this chapter for MCQs and important question at</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:59:08 +0000</pubDate>
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