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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 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 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>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>Exercise 6.2</title>
            <link>https://www.mathcity.org/matric/9th_science/ex-6-2</link>
            <description>Exercise 6.2

On the following page we have given the solution of Exercise 6.2 of Mathematics 9 (Science) published by Caravan Book House, Lahore.

We have created this page and it will be updated to add new solutions occasionally. Please stay in touch with this page.$\frac{x^2-x-6}{x^2-9}+\frac{x^2+2x-24}{x^2-x-12}$\begin{align} \frac{x^2-x-6}{x^2-9}&amp;+\frac{x^2+2x-24}{x^2-x-12}\\
&amp;=\frac{x^2-3x+2x-6}{(x)^2-(3)^2}+\frac{x^2+6x-4x-24}{x^2-4x+3x-12}\\&amp;= \frac{x(x-3)+2(x-3)}{(x-3)(x+3)}+\frac{x(x+6…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:48:08 +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>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 2.6</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>Exercise 4.1</title>
            <link>https://www.mathcity.org/matric/9th_science/ex-4-1</link>
            <description>Exercise 4.1

On the following page we have given the solution of Exercise 4.1 of Mathematics 9 (Science) published by Caravan Book House, Lahore.

We have created this page and it will be updated to add new solutions occasionally. Please stay in touch with this page.$3x^2+\frac{1}{x}-5$$3x^3-4x^2-x\sqrt{x}+3$$x^2-3x+\sqrt{2}$$\frac{3x}{2x-1}+8$$3x^2+\frac{1}{x}-5$$No (Reason:\frac{1}{x})$$3x^3-4x^2-x\sqrt{x}+3$$No (Reasons  \sqrt{x})$$x^2-3x+\sqrt{2}$$Yes$$\frac{3x}{2x-1}+8$$No (Reason:\frac{1}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:48:06 +0000</pubDate>
        </item>
        <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>
        </item>
        <item>
            <title>Exercise 6.1</title>
            <link>https://www.mathcity.org/matric/9th_science/ex-6-1</link>
            <description>Exercise 6.1

On the following page we have given the solution of Exercise 6.1 of Mathematics 9 (Science) published by Caravan Book House, Lahore.

We have created this page and it will be updated to add new solutions occasionally. Please stay in touch with this page.$39x^7y^3z$$91x^5y^6 z^7$$102xy^2z$$85x^2yz$$187xyz^2$$39x^7y^3z=13\times 3\times x^7 y^3 z$$91x^5y^6 z^7=13\times 7\times x^5 y^6 z^7$$13 x^5y^3z$$102xy^2z=2\times 3\times 17 xy^2z$$85x^2yz=3\times 17 x^2 y z$$187xyz^2 = 11\times 1…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:48:08 +0000</pubDate>
        </item>
        <item>
            <title>Exercise 6.3</title>
            <link>https://www.mathcity.org/matric/9th_science/ex-6-3</link>
            <description>Exercise 6.3

On the following page we have given the solution of Exercise 6.3 of Mathematics 9 (Science) published by Caravan Book House, Lahore.

We have created this page and it will be updated to add new solutions occasionally. Please stay in touch with this page.$4x^2-12xy +9y^2$$x^2-1+\frac{1}{4x^2}, (x\neq 0)$$\frac{1}{16}x^2-\frac{1}{12}xy+ \frac{1}{36}y^2$$4(a+b)^2-12(a^2-b^2)+9(a-b)^2$$\frac{4x^6-12x^3y^3+9y^6}{9x^4-24x^2y^2+16y^4},(x \neq 0)$$\left( x+\frac{1}{x}\right)^2-4\left( x-\f…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:48:09 +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>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 1.3</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>
        </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>Operation Research: Handwritten Notes</title>
            <link>https://www.mathcity.org/notes/operation-research-handwritten-notes</link>
            <description>Operation Research: Handwritten Notes

[Operation Research: Handwritten Notes]
Operation research (OR) is a scientific field that enhances organisational decision-making and problem-solving via the application of mathematical and analytical techniques. The management and administration of many processes, including military, governmental, economic, and industrial ones, include the use of scientific principles. OR is carried out by a group of professionals from various linked fields, depending on …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 05 Aug 2023 16:53:29 +0000</pubDate>
        </item>
        <item>
            <title>Unit 06: Conic Section: Mathematics FSc part 2</title>
            <link>https://www.mathcity.org/fsc/fsc_part_2_solutions/ch06/view</link>
            <description>Unit 06: Conic Section: Mathematics FSc part 2

Notes (Solutions) of Unit 06: Conic Section, Calculus and Analytic Geometry, MATHEMATICS 12 (Mathematics FSc Part 2 or HSSC-II), Punjab Text Book Board Lahore. There are nine exercises in this chapter. Please see the main page of this chapter for MCQs and important question</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 17:00:23 +0000</pubDate>
        </item>
        <item>
            <title>View Online (Solutions of Unit 06)</title>
            <link>https://www.mathcity.org/fsc/fsc_part_2_solutions/ch06/viewer</link>
            <description>View Online (Solutions of Unit 06)

Notes (Solutions) of Unit 06: Conic Section, Calculus and Analytic Geometry, MATHEMATICS 12 (Mathematics FSc Part 2 or HSSC-II), Punjab Text Book Board Lahore. From this page, you can also download PDF of the notes.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 17:00:22 +0000</pubDate>
        </item>
        <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>
        </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 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>B-Course of Mathematics (Paper A &amp; B)</title>
            <link>https://www.mathcity.org/bsc/paper_pattern/sargodha_university/b-course_of_mathematics</link>
            <description>B-Course of Mathematics (Paper A &amp; B)

This subject is consists of two papers of 100 marks each. One is called “Paper A” and other is called “Paper B”. This page is updated on February 15, 2015. This syllabus is for 1st Annual 2015 and onward organized by University of Sargodha, Sargodha.$(\lambda ,\mu )$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:55:55 +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>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 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 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>
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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>
        </item>
        <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>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>
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        <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>
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        <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>
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        <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>
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        <item>
            <title>Fundamental of Complex Analysis (Solutions of Some Exercises)</title>
            <link>https://www.mathcity.org/notes/fundamental-of-complex-analysis-prof-m-saleem</link>
            <description>Fundamental of Complex Analysis (Solutions of Some Exercises)

[Fundamental of Complex Analysis, Solutions of Some Exercises]

Complex analysis is the study of functions that exist in the complex plane, that is, functions with complex arguments and complex outputs. With roots in the 18th century and the years just before, it is one of the classical branches of mathematics. In the 20th century, significant figures in mathematics who are connected to complex numbers include Euler, Gauss, Riemann, …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 15 Apr 2023 18:26:12 +0000</pubDate>
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        <item>
            <title>Review exercise</title>
            <link>https://www.mathcity.org/matric/9th_science/review_exercise</link>
            <description>Review exercise

On the following page we have given the solution of Review exercise of Mathematics 9 (Science) published by Caravan Book House, Lahore.

We have created this page and it will be updated to add new solutions occasionally. Please stay in touch with this page.$x-2$$x^2+x-6$$x^2+x-6$$x+3$$x-2$$x+2$$c$$a^3+b^3$$a^2-ab+b^2$$a+b$$a^2-ab+b^2$$(a-b)^2$$a^2+b^2$$c$$x^2-5x+6$$x^2-x-6$$x-3$$x+2$$x^2-4$$x-2$$a$$a^2-b^2$$a^3-b^3$$a-b$$a+b$$a^2+ab+b^2$$a^2-ab+b^2$$a$$x^2+3x+2$$x^2+4x+3$$x^2+5x…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:48:10 +0000</pubDate>
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        <item>
            <title>General Mathematics (Paper A &amp; B)</title>
            <link>https://www.mathcity.org/bsc/paper_pattern/sargodha_university/general_mathematics</link>
            <description>General Mathematics (Paper A &amp; B)

This subject is consists of two papers of 100 marks each. One is called “Paper A” and other is called “Paper B”. This syllabus is for 1st Annual 2015 and onward organized by University of Sargodha (UoS), Sargodha.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:55:55 +0000</pubDate>
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        <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 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>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>
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        <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>
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        <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>
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        <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>
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        <item>
            <title>Exercise 2.6 (Solutions)</title>
            <link>https://www.mathcity.org/matric/9th_science/unit_02/exercise_2.6</link>
            <description>Exercise 2.6 (Solutions)

Question 1

Identify the following statements as true or false.
(i) $\sqrt{-3}\cdot\sqrt{-3} = 3$

(ii) $i^{73}=-i$

(iii) $i^{10} = -1$

(iv) Complex conjugate of  $(-6i + i^2) is (-1 + 6i)$

(v) Difference of complex numbers $z = a + ib$ and its conjugate is a real number.

(vi) If $(a-1)-(b+3)i = 5+8i$, then a = 6 &amp; b = -11

(vii) Product of complex number and its conjugate is always a non-negative real number.$a+ib$$(2+3i)+(7-2i)$$2(5+4i)+3(7-4i)$$-(-3+5i)-3(4+9i)$$…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 17:00:37 +0000</pubDate>
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        <item>
            <title>Fundamental of Complex Analysis: Viewer</title>
            <link>https://www.mathcity.org/msc/notes/fundamental_of_complex_analysis/viewer</link>
            <description>Fundamental of Complex Analysis: Viewer

Solutions of some exercises from Fundamental of Complex Analysis written by Dr. M. Iqbal and published by Ilmi Kitab Khana, Lahore- PAKISTAN. These are handwritten notes by Prof.(Rtd) Muhammad Saleem.

You can also download PDF of solutions from this page.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 17:00:41 +0000</pubDate>
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        <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>Chapter 02: Viewer</title>
            <link>https://www.mathcity.org/bsc/notes_of_calculus_with_analytic_geometry/ch02_derivatives/viewer</link>
            <description>Chapter 02: Viewer

Notes of Chapter 02: The Derivatives of Calculus with Analytic Geometry written by Dr. S. M. Yusuf and Prof. Muhammad Amin, published by Ilmi Kitab Khana, Lahore - PAKISTAN. You can also download a PDF file of respective exercise from this page.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:51:47 +0000</pubDate>
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        <item>
            <title>Chapter 04: Viewer</title>
            <link>https://www.mathcity.org/bsc/notes_of_calculus_with_analytic_geometry/ch04_techniques_of_integration_farooq/viewer</link>
            <description>Chapter 04: Viewer

These notes are written by Prof. Muhammad Farooq. We are very thankful to him for providing these notes.



List of all exercises of chapter 04

	*  Solution of Exercise 4.1 

	*  Solution of Exercise 4.2

	*  Solution of Exercise 4.3

	*  Solution of Exercise 4.4

	*  Solution of Exercise 4.5

	*  Solution of Exercise 4.6</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:52:02 +0000</pubDate>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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 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>
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        <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 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 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 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 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 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 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>
        </item>
        <item>
            <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>
        </item>
        <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>
        </item>
        <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>
        </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 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>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 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 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 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 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 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 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>
        </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 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 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 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>
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            <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <item>
            <title>Operation Research by Sir Haidar Ali</title>
            <link>https://www.mathcity.org/notes/operation-research-haidar-ali</link>
            <description>Operation Research by Sir Haidar Ali

[Notes of Operation Research by Sir Haidar Ali]
These notes are provided and composed by Mr. Muzammil Tanveer. We are really very thankful to him for providing these notes and appreciates his effort to publish these notes on MathCity.org. These are based on lectures delivered by Sir Haidar Ali at GC University Faisalabad.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 21 Mar 2025 17:42:28 +0000</pubDate>
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            <title>Unit 05: Linear Inequalities and Linear Programming</title>
            <link>https://www.mathcity.org/fsc-part2-ptb/important-questions/unit-05-linear-inequalities-and-linear-programming</link>
            <description>Unit 05: Linear Inequalities and Linear Programming

Here is the list of important questions.

	*  Graph the solution region of $2x+y \geq 2$ ---  BSIC Gujranwala (2016)
	*  Graph the feasible region subject to the following constraint: ---  BSIC Gujranwala (2016)$2x-3y \leq 6$$2x+3y \leq 12$$x \geq 0$$y \geq 0$$2x+y\geq 2$$x+2y\leq10$$x\geq0,y\geq0$$2x+3y\leq 12$$z=x+3y$$2x+5y\leq30$$5x+4y\leq20$$x\geq0$$y\geq0$$x+2y\leq 14$$3x+4y\leq 36$$2x+y\leq 10$$x\geq0, y\geq0$$f(x)=2x+5y$$-x\leq8$$-y\leq…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:47:57 +0000</pubDate>
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        <item>
            <title>Viewer: Ch 01 Complex Numbers</title>
            <link>https://www.mathcity.org/bsc/notes_of_mathematical_method/ch01_complex_numbers/viewer</link>
            <description>Viewer: Ch 01 Complex Numbers

Notes of Chapter 01: Complex Numbers of Mathematical Method written by S.M. Yusuf, A. Majeed and M. Amin, published by Ilmi Kitab Khana, Lahore - PAKISTAN. PDF file of respective exercise can be downloaded from this page.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 09 Mar 2022 19:08:50 +0000</pubDate>
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        <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>
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        <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>
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        <item>
            <title>Unit 07: Vectors: Mathematics FSc part 2</title>
            <link>https://www.mathcity.org/fsc/fsc_part_2_solutions/ch07/view</link>
            <description>Unit 07: Vectors: Mathematics FSc part 2

Notes (Solutions) of Unit 07: Vectors, Calculus and Analytic Geometry, MATHEMATICS 12 (Mathematics FSc Part 2 or HSSC-II), Punjab Text Book Board Lahore. There are three exercises in this chapter. Please see the main page of this chapter for MCQs and important question</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 17:00:25 +0000</pubDate>
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        <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>
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        <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>
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        <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>
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            <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>
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        <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>
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        <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>
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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 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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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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>
        </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>
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        <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>
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        <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 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>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 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 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 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 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>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>Special Functions by Dr. Muhey-U-Din</title>
            <link>https://www.mathcity.org/notes/special-functions-muzammil-tanveer</link>
            <description>Special Functions by Dr. Muhey-U-Din

These notes are provided and composed by Mr. Muzammil Tanveer. We are really very thankful to him for providing these notes and appreciates his effort to publish these notes on MathCity.org. Thease notes are based on the lectures by Dr. Muhey-U-Din.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 23 Jul 2023 16:48:30 +0000</pubDate>
        </item>
        <item>
            <title>PPSC Paper 2011 (Lecturer in Mathematics)</title>
            <link>https://www.mathcity.org/ppsc/ppsc-maths-2011</link>
            <description>PPSC Paper 2011 (Lecturer in Mathematics)

[PPSC Paper 2011 (Lecturer in Mathematics)]

On this page, we have given question from old (past) paper of Lecturer in Mathematics conducted in year 2011. This is a MCQs paper and answers are given at the end of the paper. At the end of the PDF is also given to download. This paper is provided by Ms. $R$$x\in R$$x^2=x$$x^2=-x$$x^2=0$$x^2=1$$6$$8$$10$$4$$G$$H$$H$$G$$2$$4$$nZ$$Z$$n$$G$$24$$a$$a^{10}$$2$$12$$10$$V$$n$$V$$n+1$$n$$n-1$$v_1,v_2,v_3,....,v_r$$…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 03 Feb 2022 11:54:32 +0000</pubDate>
        </item>
        <item>
            <title>PPSC Paper 2021 (Lecturer in Mathematics)</title>
            <link>https://www.mathcity.org/ppsc/ppsc-maths-2021</link>
            <description>PPSC Paper 2021 (Lecturer in Mathematics)

[PPSC Paper 2011 (Lecturer in Mathematics)]

On this page, we have given question from old (past) paper of Lecturer in Mathematics conducted in year 2021. This is a MCQs paper and answers are given at the end of the paper. At the end of the PDF is also given to download. This paper is provided by Ms. \(2018\)$4$\(6\)$8$$10$\(X\)\(Y\)\(X\times Y\)\(\parallel (x,y) \parallel=\parallel x\parallel+\parallel y\parallel, \,\forall \, (x,y)\in X \times Y\)\(f(…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 23 Aug 2022 17:04:49 +0000</pubDate>
        </item>
        <item>
            <title>Chapter 01: Real Numbers, Limits and Continuity</title>
            <link>https://www.mathcity.org/bsc/notes_of_calculus_with_analytic_geometry/ch01_real_numbers_limits_and_continuity</link>
            <description>Chapter 01: Real Numbers, Limits and Continuity

[Chapter 01 of Calculus with Analytic Geometry]
Notes of the book Calculus with Analytic Geometry written by Dr. S. M. Yusuf and Prof. Muhammad Amin, published by Ilmi Kitab Khana, Lahore - PAKISTAN. 

The notes of this chapter is written by Prof. $\mathbb{R}$$\mathbb{R}$$\mathbb{R}$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:45:28 +0000</pubDate>
        </item>
        <item>
            <title>Chapter 12: Application of Trigonometry</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_solutions/ch12</link>
            <description>Chapter 12: Application of Trigonometry

[Chapter 12: Application of Trigonometry]
Notes (Solutions) of Chapter 12: Application of Trigonometry, Text Book of Algebra and Trigonometry Class XI (Mathematics FSc Part 1 or HSSC-I), Punjab Text Book Board, Lahore.

Contents &amp; summary

	*  Introduction</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:46:34 +0000</pubDate>
        </item>
        <item>
            <title>A-Course of Mathematics (Paper A &amp; B)</title>
            <link>https://www.mathcity.org/bsc/paper_pattern/sargodha_university/a-course_of_mathematics</link>
            <description>A-Course of Mathematics (Paper A &amp; B)
This subject is consists of two papers of 100 marks each. One is called “Paper A” and other is called “Paper B”. This page is updated on February 15, 2015. This syllabus is for 1st Annual 2015 and onward organized by University of Sargodha, Sargodha.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:55:54 +0000</pubDate>
        </item>
        <item>
            <title>Applied Mathematics (Paper A &amp; B)</title>
            <link>https://www.mathcity.org/bsc/paper_pattern/sargodha_university/applied_mathematics</link>
            <description>Applied Mathematics (Paper A &amp; B)

This paper consista of two papers of 100 marks each. One paper is called “Paper A” and other is called “Paper B”.

Paper A

	*  NOTE: attempt two questions from each section.

SECTION-I (4/12: 17,17,17,17)

$(\lambda ,\mu )$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:55:46 +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 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>
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        <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 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 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 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>
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        <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 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 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 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, 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 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 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 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 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 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 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 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 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 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 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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            <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>
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            <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>
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            <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>
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            <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>
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            <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>
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            <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>
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            <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>
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            <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>
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            <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>
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            <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>
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            <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>
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            <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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            <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>
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            <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>
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            <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>
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            <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>
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            <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>
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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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            <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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            <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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            <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>
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        <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>
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            <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>
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            <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>
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            <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 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>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 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 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 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 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 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 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 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 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 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 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, 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 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 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 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>Exercise 2.5 (Solutions)</title>
            <link>https://www.mathcity.org/matric/9th_science/unit_02/exercise_2.5</link>
            <description>Exercise 2.5 (Solutions)

Question 1

	*  Evaluate

           (i) $i^7$			                                  (ii) $i^{50}$
           (iii) $i^{12}$                                                 (iv) $\left(-i\right)^8$
           (v) $\left(-i\right)^5$	                                  (vi)  $i^{27}$

Solution

$$\begin{array}{cl}
i^7 &amp;= {i^6}\cdot i\\
   &amp;= (i^2)^3\cdot i\\
   &amp;= {-1}^3 \cdot i\\
   &amp;= -i
\end{array}$$$$\begin{array}{cl}
i^{50} &amp;= (i^2 )^{25}\\
       &amp;= {-1}^{25}\\
       …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 17:00:37 +0000</pubDate>
        </item>
        <item>
            <title>MTH211: Discrete Mathematics (Fall 2020)</title>
            <link>https://www.mathcity.org/atiq/fa20-mth211</link>
            <description>MTH211: Discrete Mathematics (Fall 2020)



Course Objectives:

Discrete Mathematics is branch of Mathematics which deals with discrete structures
like logic. sequences, graphs, relations in contrast to Calculus. where we enjoy the
continuity of functions and the set of real numbers. This course is introduction to
discrete structures which are not the part of main stream courses.
Discrete Mathematics has applications in Computer Science. Economics and Decision
Making etc. This course will help t…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:40:14 +0000</pubDate>
        </item>
        <item>
            <title>MTH211: Discrete Mathematics (Spring 2020)</title>
            <link>https://www.mathcity.org/atiq/sp20-mth211</link>
            <description>MTH211: Discrete Mathematics (Spring 2020)



Course Objectives:

Discrete Mathematics is branch of Mathematics which deals with discrete structures
like logic. sequences, graphs, relations in contrast to Calculus. where we enjoy the
continuity of functions and the set of real numbers. This course is introduction to
discrete structures which are not the part of main stream courses.
Discrete Mathematics has applications in Computer Science. Economics and Decision
Making etc. This course will help…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:40:40 +0000</pubDate>
        </item>
        <item>
            <title>MTH211: Discrete Mathematics (Fall 2020)</title>
            <link>https://www.mathcity.org/atiq/sp21-mth211</link>
            <description>MTH211: Discrete Mathematics (Fall 2020)



Course Objectives:

Discrete Mathematics is branch of Mathematics which deals with discrete structures
like logic. sequences, graphs, relations in contrast to Calculus. where we enjoy the
continuity of functions and the set of real numbers. This course is introduction to
discrete structures which are not the part of main stream courses.
Discrete Mathematics has applications in Computer Science. Economics and Decision
Making etc. This course will help t…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 10 Jun 2021 09:02:12 +0000</pubDate>
        </item>
        <item>
            <title>MTH211: Discrete Mathematics (Spring 2022)</title>
            <link>https://www.mathcity.org/atiq/sp22-mth211</link>
            <description>MTH211: Discrete Mathematics (Spring 2022)



Course Objectives:

Discrete Mathematics is branch of Mathematics which deals with discrete structures
like logic. sequences, graphs, relations in contrast to Calculus. where we enjoy the
continuity of functions and the set of real numbers. This course is introduction to
discrete structures which are not the part of main stream courses.
Discrete Mathematics has applications in Computer Science. Economics and Decision
Making etc. This course will help…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 12 Sep 2022 04:56:59 +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>PPSC Paper 2015 (Lecturer in Mathematics)</title>
            <link>https://www.mathcity.org/ppsc/ppsc-maths-2015</link>
            <description>PPSC Paper 2015 (Lecturer in Mathematics)

[PPSC Paper 2011 (Lecturer in Mathematics)]

On this page, we have given question from old (past) paper of Lecturer in Mathematics conducted in year 2011. This is a MCQs paper and answers are given at the end of the paper. At the end of the PDF is also given to download. This paper is provided by Kaushef Salamat. We are very thankful to her for providing this paper.\(\displaystyle \int_{-4}^{0}\frac{tdt}{\sqrt{16-t62}}\)$0$$-4$$4$\(A\cos wt+B\sin wt\)$\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 18 Jan 2022 10:20:00 +0000</pubDate>
        </item>
        <item>
            <title>MCQs: Ch 04 Quadratic Equations</title>
            <link>https://www.mathcity.org/fsc-part1-ptb/mcq-bank/ch04</link>
            <description>MCQs: Ch 04 Quadratic Equations

High quality MCQs of Chapter 01 Number System of Text Book of Algebra and Trigonometry Class XI (Mathematics FSc Part 1 or HSSC-I), Punjab Text Book Board, Lahore. The answers are given at the end of the page.

MCQs

$ax^2+bx+c=0$$ax^2+bx+c=0$$b \neq 0$$c \neq 0$$a \neq 0$$x$$ax^2+bx+c$$ax^2+bx+c=0$$\{a,b\}$$ax^2+bx+c=0$$a\neq 0$$x= \frac{b \pm \sqrt{b^2-4ac}}{a}$$x= \frac{-b \pm \sqrt{b^2+4ac}}{2a}$$x= \frac{-b \pm \sqrt{4ac-b^2}}{2a}$$x= \frac{-b \pm \sqrt{b^2-…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:47:50 +0000</pubDate>
        </item>
        <item>
            <title>Chapter 01: Viewer</title>
            <link>https://www.mathcity.org/bsc/notes_of_calculus_with_analytic_geometry/ch01_real_numbers_limits_and_continuity/viewer</link>
            <description>Chapter 01: Viewer

Notes of “Chapter 01: Real numbers, limits and continuity” of Calculus with Analytic Geometry written by Dr. S. M. Yusuf and Prof. Muhammad Amin, published by Ilmi Kitab Khana, Lahore - PAKISTAN. You can also download a PDF file of respective exercise from this page.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:51:44 +0000</pubDate>
        </item>
        <item>
            <title>Syllabus &amp; Paper Pattern for General Mathematics (Split Program)</title>
            <link>https://www.mathcity.org/bsc/paper_pattern/punjab_university/b.sc._paper_pattern_for_general_mathematics_split_program</link>
            <description>Syllabus &amp; Paper Pattern for General Mathematics (Split Program)

There was one examination after two years for BA/BSc Program from University of Punjab (PU), Lahore but from this year (2016), PU has made changes in its examination policies for the said program. The BA/BSc Program has been split into two parts. Syllabus is break into two part year wise. After the each year of the program candidate has to appeared in examination instead of appearing after two year. In this regards syllabus of Gen…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:55:21 +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 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 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 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 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 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, 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 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 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 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 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>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 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 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 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 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 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 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 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 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 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 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 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 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 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 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>
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        <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 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>
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        <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 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 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 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 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 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 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 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 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, 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 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 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 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 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>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 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>
        </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 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 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 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 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 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 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 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 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>
        </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>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 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 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 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 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 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 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 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 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>Exercise 11.1 (Solutions)</title>
            <link>https://www.mathcity.org/matric/9th_science/unit11/11-1</link>
            <description>Exercise 11.1 (Solutions)

On this page solutions of Exercise of Unit 11: Parallelograms and Triangles of Mathematics 9 written by Dr. Karamat H. Dar and Prof. Irfan-ul-Haq has been given. There are two questions in this exercise and solution of both the questions are given below.$ABCD$$m\angle B=130^\circ$$m\angle B=m\angle D$$m\angle B=m\angle D=130^\circ$\begin{align}
&amp; m\angle A +\,\,m\angle B=180^\circ \\ 
&amp; m\angle A+\,{{130}^{\circ }}={{180}^{\circ }}\\
&amp; m\angle A={{180}^{\circ }}-{{130}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 20 Mar 2023 17:51:29 +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/ICS Part 2 Solutions</title>
            <link>https://www.mathcity.org/fsc/fsc_part_2_solutions</link>
            <description>FSc/ICS Part 2 Solutions

[Calculus and Analytic Geometry, MATHEMATICS 12]
Notes (Solutions) of Calculus and Analytic Geometry, MATHEMATICS 12 (Mathematics FSc/ICS Part 2 or HSSC-II), Punjab Text Book Board Lahore.
 There are seven units in this book and we have work hard to make easy and suitable solutions for students and teachers so that it help them learn things quickly and easily. Please click on a desire unit to view the solution of any particular exercise. This work is licensed under a Cr…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 21 Mar 2025 18:12:01 +0000</pubDate>
        </item>
        <item>
            <title>Complex Analysis by M Usman Hamid</title>
            <link>https://www.mathcity.org/notes/complex-analysis-m-usman-hamid</link>
            <description>Complex Analysis by M Usman Hamid

[Complex Analysis by M Usman Hamid]
We are really very thankful to Muhammad Usman Hamid for providing these notes and appreciates his effort to publish these notes on MathCity.org

It covers the one part of the syllabus of Complex Analysis paper of MSc Mathematics. See the contents of the notes given below to see the topics covered by these notes.$$
x^2+4=0, x^2+x+1=0 \text{ and } x^2-2x+3=0
$$$i=\sqrt{-1}$$i^2=-1$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 08 Feb 2025 08:11:42 +0000</pubDate>
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        <item>
            <title>Elementary Linear Algebra by Muhammad Usman Hamid</title>
            <link>https://www.mathcity.org/notes/elementary-linear-algebra-m-usman-hamid</link>
            <description>Elementary Linear Algebra by Muhammad Usman Hamid

[Elementary Linear Algebra by Muhammad Usman Hamid]

Linear Algebra is the study of vectors and linear transformations. The main objective of this course is to help students learn in rigorous manner, the tools and methods essential for studying the solution spaces of problems in mathematics, engineering, the natural sciences and social sciences and develop mathematical skills needed to apply these to the problems arising within their field of st…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 10 Dec 2023 14:05:12 +0000</pubDate>
        </item>
        <item>
            <title>Mathematical Method by Muhammad Usman Hamid</title>
            <link>https://www.mathcity.org/notes/mathematical-method-usman-hamid</link>
            <description>Mathematical Method by Muhammad Usman Hamid

[Mathematical Method by Muhammad Usman Hamid]

These notes are send by Muhammad Usman Hamid. We acknowledged his efforts to published these notes on MathCity.org.

The main objective of this course is to provide the students with a range of mathematical methods that are essential to the solution of advanced problems encountered in the fields of applied physics and engineering. In addition this course is intended to prepare the students with mathematic…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 17 Apr 2023 08:43:53 +0000</pubDate>
        </item>
        <item>
            <title>Notes for Numerical Methods by M Usman Hamid</title>
            <link>https://www.mathcity.org/notes/note-for-numerical-methods-m-usman-hamid</link>
            <description>Notes for Numerical Methods by M Usman Hamid

[Notes for Numerical Methods by M Usman Hamid]
These notes are initially provided by Mr. Anwar Khan. Later the updated version is send by Muhammad Tahir. We are really very thankful to Mr. Anwar Khan and Muhammad Tahir for providing these notes and appreciates their effort to publish these notes on MathCity.org$\left(\frac{1}{3}\right)$$\left(\frac{3}{8}\right)$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 05 Aug 2023 17:59:07 +0000</pubDate>
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        <item>
            <title>Partial Differential Equations (PDE) by Muzammil Tanveer</title>
            <link>https://www.mathcity.org/notes/partial-differential-equations-muzammil-tanveer</link>
            <description>Partial Differential Equations (PDE) by Muzammil Tanveer

[Partial Differential Equations]
These notes are provided and composed by Mr. Muzammil Tanveer. We are really very thankful to him for providing these notes and appreciates his effort to publish these notes on MathCity.org 

Name: Partial Differential Equations or PDEs</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 09 Mar 2025 09:29:35 +0000</pubDate>
        </item>
        <item>
            <title>Vector &amp; Tensor Analysis by Prof Fazal Abbas</title>
            <link>https://www.mathcity.org/notes/vector-and-tensor-analysis-by-prof-fazal-abbas</link>
            <description>Vector &amp; Tensor Analysis by Prof Fazal Abbas

[Vector &amp; Tensor Analysis by Prof Fazal Abbas]

Solution of Chapter 6: Curvilinear Coordinates of the book Vector &amp; Tensor Analysis by Prof. Dr. Nawazish Ali Shah written by Prof. Fazal Abbas Sajid. Here solutions of chapter 6 are provided by the author of the book, for the solutions of all the chapters of the book, please buy the solution manual from the market.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 24 Aug 2022 07:12:53 +0000</pubDate>
        </item>
        <item>
            <title>Chapter 03: Viewer</title>
            <link>https://www.mathcity.org/bsc/notes_of_mathematical_method/ch03_matrices/viewer</link>
            <description>Chapter 03: Viewer

Notes of Chapter 03: Matrices of Mathematical Method written by S.M. Yusuf, A. Majeed and M. Amin, published by Ilmi Kitab Khana, Lahore - PAKISTAN. PDF file of respective exercise can be downloaded from this page.



Here is the list of all available exercise of Chapter 03</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:53:09 +0000</pubDate>
        </item>
        <item>
            <title>Chapter 08: Rectilinear Motion</title>
            <link>https://www.mathcity.org/bsc/notes_of_mechanics/introduction_to_mechanics/ch08-rectilinear-motion</link>
            <description>Chapter 08: Rectilinear Motion

Notes of Chapter 08: Rectilinear Motion: Introduction to Mechanics by Q. K. Ghori published by West Pak Publishing Company (Pvt) Ltd. Thanks to Mr. Tahir Aziz and Atiq ur Rehman for sending these notes.

	*  Motion with constant acceleration</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:55:09 +0000</pubDate>
        </item>
        <item>
            <title>Pure Mathematics (Paper A &amp; B)</title>
            <link>https://www.mathcity.org/bsc/paper_pattern/sargodha_university/pure_mathematics</link>
            <description>Pure Mathematics (Paper A &amp; B)

This paper consist of two papers of 100 marks each. One paper is called “Paper A” and the other is called “Paper B”.

Paper A

	*  NOTE: attempt two questions from each section.

SECTION-I (4/12: 17,17,17,17)</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:55:59 +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 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 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>
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        <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, 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 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 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 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 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>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 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 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 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 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 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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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 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 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>
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        <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>
        </item>
        <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>
        </item>
        <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>
        </item>
        <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 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>
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        <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>
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        <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 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>
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        <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>
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        <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>
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        <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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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>
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        <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>
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        <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>
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        <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>
        </item>
        <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 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 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>
        </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 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 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 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 1.4</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>
        </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>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>
        </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 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 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 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>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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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>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>
        </item>
        <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 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>
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        <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 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 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 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 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 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>Exercise 2.2 (Solutions)</title>
            <link>https://www.mathcity.org/matric/9th_science/unit_02/exercise_2.2</link>
            <description>Exercise 2.2 (Solutions)

Question 1

Identify the property used in the following,

	*  (i) $a + b = b + a$ ... .....
	*  (ii) $(ab)c = a(bc)$ ... ... ...
	*  (iii) $7 \times 1 = 7$ ... ... ...
	*  (iv) $x &gt; y$ or $x = y$ or $x&lt; y$ ... ... ...	
	*  (v) $ab = ba$ ... ... ...
	*  (vi) $a + c = b + c \Rightarrow a = b$ ... ... ...
	*  (vii) $5 + (-5) = 0$ ... ... ...
	*  (viii) $7 \times \frac{1}{7} = 1$$a &gt; b \Rightarrow ac &gt; bc? (c &gt;0)$$a + b = b + a$$(ab)c = a(bc)$$7 \times 1 = 7$$x &gt; y$$x = y$$…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 17:00:36 +0000</pubDate>
        </item>
        <item>
            <title>Exercise 2.3 (Solutions)</title>
            <link>https://www.mathcity.org/matric/9th_science/unit_02/exercise_2.3</link>
            <description>Exercise 2.3 (Solutions)

Question 1

Write each radical expression in exponential notation and each exponential expression in radical notation, Do not simplify.


	* (i) $\sqrt[3]{-64}$	                            *(ii) $2^{35}$
           
				*  (iii) $-7^\frac{1}{3}$                           * (iv) $y^\frac{-2}{3}$$\sqrt[3]{-64} = -64^\frac{1}{3}$$2^\frac{3}{5} = \sqrt[5]{2}^{3}$$-7^\frac{1}{3} = -\sqrt[3]{7}$$y^\frac{-2}{3} = \sqrt[3]{y}^{-2}$$ 5^\frac{1}{5} = \sqrt{5}$$2^\frac{2}{3} = \sq…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 17:00:36 +0000</pubDate>
        </item>
        <item>
            <title>Exercise 2.4 (Solutions)</title>
            <link>https://www.mathcity.org/matric/9th_science/unit_02/exercise_2.4</link>
            <description>Exercise 2.4 (Solutions)

Question 1

Use law of exponent to simplify.

	*  (i) $\frac{(243)^{\frac{-2}{3}}(32)^{\frac{-1}{5}}}{\sqrt(196)^{-1}}$	    
	*  (ii) $\left(2x^5y^{-4}\right)\left(-8x^{-3}y^2\right)$	           
	*  (iii) $\left(\frac{x^{-2}y^{-1}z^{-4}}{x^4y^{-3}z^0}\right)^{-3}$
	*  (iv) $\frac{\left(81\right)^n.3^5-\left(3\right)^{4n-1}\left(243\right)}{\left(9^2n\right)\left(3^3\right)}$

Solution


(i) 
$$\begin{array}{cl}
\begin{array}{cl}
\frac{(243)^{\frac{-2}{3}}(32)^{\frac{-1…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 17:00:37 +0000</pubDate>
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        <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>Khuram Ali Khan</title>
            <link>https://www.mathcity.org/khuram</link>
            <description>Khuram Ali Khan



Khuram Ali Khan, PhD

Associate Professor

Department of Mathematics

University of Sargodha

Sargodha - PAKISTAN.

Email: &lt;khuram@MathCity.org&gt;



Field of Research: Difference and functional equations, Real functions, Mathematical inequalities involving convex functions, Time Scales Calculus, Soft Sets</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 13 Jun 2025 12:03:59 +0000</pubDate>
        </item>
        <item>
            <title>MathCraft</title>
            <link>https://www.mathcity.org/mathcraft</link>
            <description>MathCraft


Introducing “MathCraft”: Your Solution for Document Transformation!
[MathCraft]

We are thrilled to unveil our latest service, MathCraft, tailored exclusively for the mathematics community. With MathCraft, you can easily get code from PDFs and pictures into LaTeX or Word files without spending too much money. Whether you&#039;re a student, researcher, or teacher, MathCraft can help you create your math documents in the format you want.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 14 Apr 2024 10:56:57 +0000</pubDate>
        </item>
        <item>
            <title>Notes of Vector Analysis</title>
            <link>https://www.mathcity.org/bsc/notes_of_vector_analysis</link>
            <description>Notes of Vector Analysis

[Vector Ananlysis]
Notes of the vector analysis are given on this page. These notes are helpful for BSc or equivalent classes. These notes are written by Amir Taimur Mohmand of University of Peshawar.
The books of these notes is not known. If you know about the book, please inform us.$f$$P$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:40:54 +0000</pubDate>
        </item>
        <item>
            <title>FSc Part 1 Model Papers</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_model_papers</link>
            <description>FSc Part 1 Model Papers

Federal Board of Intermediate &amp; Secondary Education, Islamabad
 ARW Model Paper 2008   View Online  Download PDF (69KB)   ARW Official Model Paper (with solution)   View Online Download PDF (154KB)   ARW Model Paper 1 (Old)   View Online Download PDF (103KB)   ARW Model Paper 2 (Old)   View Online Download PDF (96KB)</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:42:38 +0000</pubDate>
        </item>
        <item>
            <title>Solution &amp; Area of Oblique Triangle</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_solution_area_of_oblique_triangle</link>
            <description>Solution &amp; Area of Oblique Triangle

Here is the list of all the formulas used in Chapter 12 of FSc Part 1. If there is difficulty to remember these formulas then take a print of this page and see formula from this page while solving the question. After a while you will learn all formulas by heart. To download the PDF of this page see below.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:42:41 +0000</pubDate>
        </item>
        <item>
            <title>FSc Part 2 Model Papers</title>
            <link>https://www.mathcity.org/fsc/fsc_part_2_model_papers</link>
            <description>FSc Part 2 Model Papers

Federal Board of Intermediate &amp; Secondary Education, Islamabad
 ARW 1st Model Paper 2009   View Online  Download PDF (84KB)   ARW Official Model Paper (with solution)   Download PDF (233KB)  
Board of Intermediate &amp; Secondary Education.

All the boards in Punjab expect Federal Board have the same paper pattern.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:42:48 +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>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>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>Mathematical Method by Sir Muhammad Awais Aun</title>
            <link>https://www.mathcity.org/notes/mathematical-method-muzammil-tanveer</link>
            <description>Mathematical Method by Sir Muhammad Awais Aun

[Mathematical Method by Muzammil Tanveer]

Mathematical methods are the approaches employed by mathematicians to address issues in mathematics and science. Algebra, functions, relations and associated graphs, calculus, and statistics are examples of mathematical techniques. Through their usage in resolving practical issues, they are applied to modelling.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 17 Apr 2023 09:02:35 +0000</pubDate>
        </item>
        <item>
            <title>Multivariable Calculus by Sheikh Muhammad Saleem Shahzad</title>
            <link>https://www.mathcity.org/notes/multivariable-calculus-sheikh-muhammad-saleem-shahzad</link>
            <description>Multivariable Calculus by Sheikh Muhammad Saleem Shahzad

[Multivariable Calculus by Sheikh Muhammad Saleem Shahzad]

	*  Have you ever wondered how we can understand the speed of a moving object at any instant of time?
	*  Did you know that Calculus can help us predict future trends by analyzing patterns in data?</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 17 Dec 2023 17:13:50 +0000</pubDate>
        </item>
        <item>
            <title>Numerical Analysis by M Usman Hamid</title>
            <link>https://www.mathcity.org/notes/numerical-analysis-by-m-usman-hamid</link>
            <description>Numerical Analysis by M Usman Hamid

These notes are initially provided by Mr. Anwar Khan. Later the updated version is send by Muhammad Tahir. We are really very thankful to Mr. Anwar Khan and Muhammad Tahir for providing these notes and appreciates their effort to publish these notes on MathCity.org</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 05 Aug 2023 17:01:51 +0000</pubDate>
        </item>
        <item>
            <title>Numerical Analysis II</title>
            <link>https://www.mathcity.org/notes/numerical-analysis-ii</link>
            <description>Numerical Analysis II

[Numerical Analysis by Muzammil Tanveer]
These notes are provided and composed by Mr. Muzammil Tanveer. We are really very thankful to him for providing these notes and appreciates his effort to publish these notes on MathCity.org.
 Name    Numerical Analysis II    Compiled by  Muzammil Tanveer</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 05 Aug 2023 17:56:32 +0000</pubDate>
        </item>
        <item>
            <title>Ordinary Differential Equations (ODE) by Hammad Safi</title>
            <link>https://www.mathcity.org/notes/ordinary-differential-equations-hamad-safi</link>
            <description>Ordinary Differential Equations (ODE) by Hammad Safi

[Ordinary Differential Equations by Hammad Safi]
An equation containing the derivatives of one or more dependent variables with respect to one or more independent variables is said to be a differential equation or a differential equation is an equation which contains one or more terms and derivatives of one or more dependent variables with respect to other variables (independent variables) or an equation that contains derivatives of dependent…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 09 Mar 2025 09:26:46 +0000</pubDate>
        </item>
        <item>
            <title>Kaushef Salamat</title>
            <link>https://www.mathcity.org/people/kaushef</link>
            <description>Kaushef Salamat
[Kaushef Salamat]
[Solved Paper by Kaushef Salamat]

We are very thankful to Ms. Kaushef Salamat for providing us notes.

The author has done MPhil in Mathematics from Lahore Garrison University with Gold Medal. She is a lecturer in Queen Mary College Lahore. She also works as an online tutor for O Level and A Level Students.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 20 Jan 2023 17:40:22 +0000</pubDate>
        </item>
        <item>
            <title>Quotes for the March</title>
            <link>https://www.mathcity.org/quote-of-the-day/mar</link>
            <description>Quotes for the March
 
 “نئی ریاضی” کی اہمیت بنیادی طور پر اس حقیقت میں پنہاں ہے کہ اس نے ہمیں ڈسک اور دائرے کے درمیان فرق سکھایا ہے۔ [اسحاق ٹودھنٹر (1820-1884)]</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 28 Apr 2023 18:08:23 +0000</pubDate>
        </item>
        <item>
            <title>Quotes for the May</title>
            <link>https://www.mathcity.org/quote-of-the-day/may</link>
            <description>Quotes for the May
 
مختصراً، پوری دنیا خلا اور وقت میں اشیا کی ریاضیاتی طور پر ظاہر کی جانے والی حرکات کا مجموعہ ہے، اور پوری کائنات ایک عظیم، ہم آہنگ اور ریاضیاتی طور پر تیار کی گئی مشین ہے۔۔۔</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 28 Apr 2023 18:45:11 +0000</pubDate>
        </item>
        <item>
            <title>Chapter 02: Groups</title>
            <link>https://www.mathcity.org/bsc/notes_of_mathematical_method/ch02_groups</link>
            <description>Chapter 02: Groups

[Chapter 02: Groups]
Notes of the book Mathematical Method written by S.M. Yusuf, A. Majeed and M. Amin, published by Ilmi Kitab Khana, Lahore - PAKISTAN.

Contents and summary

	*  Definition (axioms of group)
	*  Definition ( commutative group )
	*</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Mon, 11 Dec 2023 13:00:23 +0000</pubDate>
        </item>
        <item>
            <title>Chapter 11: The Laplace Transform</title>
            <link>https://www.mathcity.org/bsc/notes_of_mathematical_method/ch11_the_laplace_transform</link>
            <description>Chapter 11: The Laplace Transform

Notes of the book Mathematical Method written by S.M. Yusuf, A. Majeed and M. Amin. This book is published by Ilmi Kitab Khana, Lahore - PAKISTAN. Solutions of Chapter 11: The Laplace Transform are given here in pdf form.  $f$$[0,\infty)$$f$$\mathcal{L}(f)$$F$$
provided the above improper integral converges. We have $</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 29 May 2022 17:43:26 +0000</pubDate>
        </item>
        <item>
            <title>Unit 03: Integration</title>
            <link>https://www.mathcity.org/fsc-part2-ptb/important-questions/unit-03-integration</link>
            <description>Unit 03: Integration

Here is the list of important questions.

	*  Evaluate $\int \frac{1}{\sqrt{x}(\sqrt{x}+1)}dx$  ---  BSIC Gujranwala (2016)
	*  Find $\int \frac{1}{1+ cosx}dx$  ---  BSIC Gujranwala (2016)
	*  Evaluate $\int \frac{1}{x \ln x}dx$  ---  BSIC Gujranwala (2016)
	*  Find $\int x \ln x dx$  ---  BSIC Gujranwala (2016)
	*  Evaluate $\int e^{2x}(-sinx+2cosx)dx$  ---  BSIC Gujranwala (2016)$\int^2_1(x^2+1)dx$$\int^{\frac{\pi}{4}}_0 \sec x(\sec x+\tan x)dx$$\sin y cosec x \frac{dy}{d…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:47:55 +0000</pubDate>
        </item>
        <item>
            <title>Chapter 02: Sets, Functions and Groups</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_solutions/ch02</link>
            <description>Chapter 02: Sets, Functions and Groups

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 Text Book Board, Lahore.

[Chapter 02: Sets, Functions and Groups]

Contents &amp; summary

	*  Introduction$p\leftrightarrow q$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 05 Apr 2023 12:54:57 +0000</pubDate>
        </item>
        <item>
            <title>Chapter 03: Matrices and Determinants</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_solutions/ch03</link>
            <description>Chapter 03: Matrices and Determinants

[Chapter 03: Matrices and Determinants]

Notes (Solutions) of Chapter 03: Matrices and Determinants, Text Book of Algebra and Trigonometry Class XI (Mathematics FSc Part 1 or HSSC-I), Punjab Text Book Board, Lahore.

Contents &amp; summary

	*  Introduction$2\times2$$2\times2$$2\times2$$n\geq 3$$n\geq 3$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:46:27 +0000</pubDate>
        </item>
        <item>
            <title>Chapter 06: Sequences and Series</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_solutions/ch06</link>
            <description>Chapter 06: Sequences and Series

[Chapter 06: Sequences and Series]
Notes (Solutions) of Chapter 06: Sequences and Series, Text Book of Algebra and Trigonometry Class XI (Mathematics FSc Part 1 or HSSC-I), Punjab Text Book Board, Lahore.

Contents &amp; summary

	*  Introduction
	*  Types of Sequences$l,m,n$$p$$q$$r$$$l(q-r)+m(r-p)+n(p-q)=0$$$a_1$$d$$$\begin{align}l=a_1+(p-1)d,\\ m=a_1+(q-1)d,\\ n=a_1+(r-1)d.\end{align}$$
Now $$\begin{align}L.H.S &amp;=  l(q-r)+m(r-p)+n(p-q)\\
&amp;= lq-lr+mr-mp+np-nq\\
&amp;=…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:46:29 +0000</pubDate>
        </item>
        <item>
            <title>Chapter 14: Solutions of Trigonometric Equation</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_solutions/ch14</link>
            <description>Chapter 14: Solutions of Trigonometric Equation

[Chapter 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 Text Book Board, Lahore.

Contents &amp; summary
${\sin ^{ - 1}}A + {\sin ^{ - 1}}B = {\sin ^{ - 1}}\left( {A\sqrt {1 - {B^2}}  + B\sqrt {1 - {A^2}} } \right)$${\sin ^{ - 1}}A - {\sin ^{ - 1}}B = {\sin ^{ - 1}}\left( {A\sqrt {1 - {B^2}}  - B\sqr…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:46:37 +0000</pubDate>
        </item>
        <item>
            <title>MCQs with key</title>
            <link>https://www.mathcity.org/fsc/fsc_part_2_mcqs/mcqs_with_key</link>
            <description>MCQs with key

[MCQs Choice]
In this one PDF, MCQs of all chapters of FSc Part2 are given. There are seven chapters. Keys of MCQs is starting from page 51.

SAMPLE MCQs

	*  A function $I(x)=x$ is called
		*  (A) A linear function
		*  (B) An identity function
		*  (C) A quadratic function$\frac{d}{dx} \tan 3x =$$3\sec^2 3x$$\frac{1}{3}\sec^2 3x$$\cot 3x$$\sec^2 x$$y=f(x)$$y$$dy=f&#039;(x)$$dy=f&#039;(x) dx$$dy=f(x)$$\frac{dy}{dx}$$x&lt;0$$y&lt;0$$P(x,y)$$ax+by&lt;c$$1$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:46:44 +0000</pubDate>
        </item>
        <item>
            <title>Unit 01: Functions and Limits</title>
            <link>https://www.mathcity.org/fsc/fsc_part_2_solutions/ch01</link>
            <description>Unit 01: Functions and Limits

[Unit 01: Functions and Limits]
Notes (Solutions) of Unit 01: Functions and Limits, Calculus and Analytic Geometry, MATHEMATICS 12 (Mathematics FSc Part 2 or HSSC-II), Punjab Text Book Board Lahore. There are five exercises in this chapter. You can view online or download PDF. To view PDF, you must have PDF Reader installed on your system and it can be downloaded from $\lim_{x\to a}\frac{x^n-a^n}{x-a} = na^{n-1}$$\lim_{x\to0}\frac{\sqrt{x+a} - \sqrt{a}}{x} = \frac{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 03 Jun 2023 16:30:56 +0000</pubDate>
        </item>
        <item>
            <title>Unit 03: Integration</title>
            <link>https://www.mathcity.org/fsc/fsc_part_2_solutions/ch03</link>
            <description>Unit 03: Integration

[Unit 03: Integration]
Notes (Solutions) of Unit 03: Integration, Calculus and Analytic Geometry, MATHEMATICS 12 (Mathematics FSc Part 2 or HSSC-II), Punjab Text Book Board Lahore. You can view online or download PDF. To view PDF, you must have PDF Reader installed on your system and it can be downloaded from Software section.$dy$$\delta{y}$$[f(x)]^n f&#039;(x)$$[f(x)]^{-1}f&#039;(x)$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 03 Jun 2023 17:25:33 +0000</pubDate>
        </item>
        <item>
            <title>Unit 05: Linear Inequalities and Linear Programming</title>
            <link>https://www.mathcity.org/fsc/fsc_part_2_solutions/ch05</link>
            <description>Unit 05: Linear Inequalities and Linear Programming

[Unit 05: Linear Inequalities and Linear Programming]
Notes (Solutions) of Unit 05: Linear Inequalities and Linear Programming, Calculus and Analytic Geometry, MATHEMATICS 12 (Mathematics FSc Part 2 or HSSC-II), Punjab Text Book Board Lahore. You can view online or download PDF. To view PDF, you must have PDF Reader installed on your system and it can be downloaded from Software section.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:47:08 +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>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 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>View Online (Solutions of Chapter 14)</title>
            <link>https://www.mathcity.org/fsc/fsc_part_1_solutions/ch14/viewer</link>
            <description>View Online (Solutions of Chapter 14)

Notes (Solutions) of Chapter 14: Solutions of Trigonometric Equation of Text Book of Algebra and Trigonometry Class XI (Mathematics FSc Part 1 or HSSC-I), Punjab Text Book Board, Lahore. In this chapter there is only one exercise.</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 16:59:08 +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 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 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 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 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 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 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 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 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 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 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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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            <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>
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        <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>
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            <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>
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            <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>
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            <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>
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            <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>
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            <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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 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 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 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 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 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 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 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 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 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 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>
        </item>
        <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>
        </item>
        <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>
        </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 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 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 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 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 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>
        </item>
        <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>
        </item>
        <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>
        </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 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>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 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 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 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>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 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 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 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 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, 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 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>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>
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            <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>
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            <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>
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            <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>
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            <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>
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        <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>
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        <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>
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        <item>
            <title>Exercise 2.1 (Solutions)</title>
            <link>https://www.mathcity.org/matric/9th_science/unit_02/exercise_2.1</link>
            <description>Exercise 2.1 (Solutions)

Question 1

Identify which of the following are rational and irrational numbers:

(i) $\sqrt{3}$	(ii) $\frac{1}{6}$	(iii) $\pi$	(iv) $\frac{15}{2}$	(v) $7.25$	(vi)$\sqrt{29}$

Solution


	*  Rational: $\frac{1}{6}$, $\frac{15}{2}$, $7.25$
	*  Irrational: $\sqrt{3}$, $\pi$, $\sqrt{29}$

Question 2

Convert the following fraction into decimal fraction.$\frac{17}{25}$$\frac{19}{4}$$\frac{57}{8}$$\frac{205}{18}$$\frac{5}{8}$$\frac{25}{38}$$\frac{2}{3}$$\pi$$\frac{1}{9}$$\fr…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 17:00:36 +0000</pubDate>
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            <title>Preparation Guide</title>
            <link>https://www.mathcity.org/msc/syllabus/uos/preparation_guide</link>
            <description>Preparation Guide

This guide is made by Mr. Anwar Khan, PhD. We are very thankful to him for sharing. This guide is helpful to prepare papers for MSc Mathematics (annual system) from University of Sargodha. 

Part 1

1. REAL ANAYSIS

	*  Real Analysis (Notes by Syed Gul Shah)
	*  Chapter # 08 sequences and series of Mathematical Method by SM Yousaf (solutions are available $z= f(x,y)$</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 07 Feb 2021 17:00:44 +0000</pubDate>
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