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        <item>
            <title>Question 7, Exercise 10.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/ex10-2-p6</link>
            <description>Question 7, Exercise 10.2

Solutions of Question 7 of Exercise 10.2 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.${{\cos }^{4}}\theta -{{\sin }^{4}}\theta =\dfrac{1}{\sec 2\theta }$\begin{align}L.H.S&amp;={{\cos }^{4}}\theta -{{\sin }^{4}}\theta \\ 
&amp;=\left( {{\cos }^{2}}\theta -{{\sin }^{2}}\theta  \right)\left( {{\cos }^{2}}\theta +{{\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:46:00 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 Exercise 6.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-4-p7</link>
            <description>Question 7 Exercise 6.4

Solutions of Question 7 of Exercise 6.4 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.\begin{align}S&amp;=\{(i, j) ; i, j=1,2,3,4,5,6\}\\
&amp;=\left[\begin{array}{llllll}
(1,1) &amp; (1,2) &amp; (1,3) &amp; (1,4) &amp; (1,5) &amp; (1,6) \\
(2,1) &amp; (2,2) &amp; (2,3) &amp; (2,4) &amp; (2,5) &amp; (2,6) \\
(3,1) &amp; (3,2) &amp; (3,3) &amp; (3,4) &amp; (3,5) &amp; (3,6) \\
(4,1) &amp; (4,2) &amp; (…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:53 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 and 2 Exercise 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 7, Exercise 1.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit01/ex1-2-p6</link>
            <description>Question 7, Exercise 1.2

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

Question 7(i)
$\dfrac{2+3i}{5-2i}$\begin{align}&amp;\dfrac{2+3i}{5-2i} \\
=&amp;\dfrac{2+3i}{5-2i}\times \dfrac{5+2i}{5+2i} \quad \text{by rationalizing} \\
=&amp;\dfrac{10-6+15i+4i}{25+4}\\
=&amp;\dfrac{4+19i}{29}\\
=&amp;\dfrac{4}{29}+\dfrac{19}{29}i \end{align}$=\dfrac{4}{29}$$=\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:00 +0000</pubDate>
        </item>
        <item>
            <title>Question 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>
        </item>
        <item>
            <title>Question 1 Exercise 4.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-5-p1</link>
            <description>Question 1 Exercise 4.5

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

Question 1(i)
$3+6+12+\ldots+3.2^9$$a_1=3, \quad r=\dfrac{6}{3}=2$$a_n=3.2^9$$n$$$a_n=a_1 r^{n-1}$$\begin{align}3.2^9&amp;=3(2)^{n-1} \text { or }(2)^{n-1}=\dfrac{3.2^9}{3} \\
\Rightarrow(2)^{n-1}&amp;=2^9 \\
\Rightarrow n-1&amp;=9 \text { or } n=10  \\
\text {. Now }\qua…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:30:06 +0000</pubDate>
        </item>
        <item>
            <title>Question 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>
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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>
        </item>
        <item>
            <title>Question 6, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-2-p6</link>
            <description>Question 6, Exercise 2.2

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

Questiopn 6(i)
$\left| \begin{matrix}a-b &amp; b-c &amp; c-a  \\b-c &amp; c-a &amp; a-b  \\c-a &amp; a-b &amp; b-c  \end{matrix} \right|=0$\begin{align} L.H.S&amp;=\left| \begin{matrix}
a-b &amp; b-c &amp; c-a  \\
b-c &amp; c-a &amp; a-b  \\
c-a &amp; a-b &amp; b-c  \\
\end{matrix} \right| \\ 
&amp;=\left| \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:25 +0000</pubDate>
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        <item>
            <title>Question 3 and 4 Exercise 4.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-1-p2</link>
            <description>Question 3 and 4 Exercise 4.1

Solutions of Question 3 and 4 of Exercise 4.1 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\dfrac{1}{2}, \dfrac{2}{3} \dfrac{3}{4}, \dfrac{4}{5}, \ldots$$$\dfrac{1}{1+1}, \dfrac{2}{2+1}, \dfrac{3}{3+1}, \dfrac{4}{4+1},...$$$\dfrac{n}{n+1}$$2,-4,6,-8,10, \ldots$\begin{align}
&amp;(-1)^2 \cdot 2 \cdot 1, (-1)^3 \cdot 2 \cdot 2, (-1)^4 \cdot 2 \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 18:19:22 +0000</pubDate>
        </item>
        <item>
            <title>Question 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>
        </item>
        <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>
        </item>
        <item>
            <title>Question 1 Exercise 6.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-4-p1</link>
            <description>Question 1 Exercise 6.4

Solutions of Question 1 of Exercise 6.4 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$S=\{1,2,3,4,5,6\}$$5$$5$\begin{align}A&amp;=\{5\}\\
P(A)&amp;=\dfrac{n(A)}{n(S)}\\
&amp;=\dfrac{1}{6} \end{align}$S=\{1,2,3,4,5,6\}$$1$$1$\begin{align}B&amp;=\{\}\\
&amp;=\phi \text{then}\\
P(B)&amp;=\dfrac{n(B)}{n(S)}\\
&amp;=\dfrac{0}{6}\\
&amp;=0\end{align}$S=\{1,2,3,4,…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:49 +0000</pubDate>
        </item>
        <item>
            <title>Question 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>
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        <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>
        </item>
        <item>
            <title>Question 1 Exercise 5.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/ex5-4-p1</link>
            <description>Question 1 Exercise 5.3

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

Question 1(i)
$\dfrac{1}{1.2}+\dfrac{1}{2.3}+\dfrac{1}{3.4}+\ldots$$n$$$T_n=\dfrac{1}{n(n+1)}$$$T_n$$$\dfrac{1}{n(n+1)}=\dfrac{A}{n}+\dfrac{B}{(n+1)}$$$n(n+1)$$$1=A(n+1)+B n=(A+B) n+A$$$n$$$A+B=0 \text{and} A=1$$$A=1$\begin{align}1+B&amp;=0\\
B&amp;=-1\end{align}\beg…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:20 +0000</pubDate>
        </item>
        <item>
            <title>Question 8 Review Exercise</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/re-ex5-p6</link>
            <description>Question 8 Review Exercise

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

Question 8(i)
$n$$n^{t h}$$n^3+3^n.$$n^h$$$a_n=n^3+3^n$$\begin{align}\sum_{r=1}^n a_r&amp;=\sum_{r=1}^n r^3+\sum_{r=1}^n 3^r \\
&amp; =[\dfrac{n(n+1)}{2}]^2+\dfrac{3(3^n-1)}{3-1} \\
&amp; =\dfrac{n^2(n+1)^2}{4}+\dfrac{3}{2}(3^n-1) \end{align}$n$$$S_n=\dfrac{n^2(n+1…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:25 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 &amp; 4 Exercise 6.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-1-p2</link>
            <description>Question 3 &amp; 4 Exercise 6.1

Solutions of Question 3 &amp; 4 of Exercise 6.1 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\dfrac{1}{6 !}+\dfrac{2}{7 !}+\dfrac{3}{8 !}=\dfrac{75}{8 !}$\begin{align}\dfrac{1}{6 !}+\dfrac{2}{7 !}+\dfrac{3}{8 !}&amp;=\dfrac{1}{6 !}+\dfrac{2}{7.6 !}+\dfrac{3}{8.7 .6 !} \\
&amp; =\dfrac{56+16+3}{8 !}\\
&amp;=\dfrac{75}{8 !}\end{align}$\df…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:30 +0000</pubDate>
        </item>
        <item>
            <title>Question 12 Exercise 6.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-2-p8</link>
            <description>Question 12 Exercise 6.2

Solutions of Question 12 of Exercise 6.2 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$8.$$n=8$$\mathrm{O}$$m_1=3$\begin{align}
 \left(\begin{array}{c}
n \\
m 1
\end{array}\right)&amp;=\left(\begin{array}{l}
8 \\
3
\end{array}\right) \\
&amp; =\dfrac{8 !}{3 !}\\
&amp;=\dfrac{8 \cdot 7 \cdot 6 \cdot 5 \cdot 4 \cdot 3 !}{3 !}\\
&amp;=6,720 \e…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:41 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 Exercise 6.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-3-p7</link>
            <description>Question 9 Exercise 6.3

Solutions of Question 9 of Exercise 6.3 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$8$$6$$7$$7$$6.$$=7+6=13$${ }^7 C_4$${ }^6 C_4$\begin{align}{ }^7 C_4 \cdot{ }^6 C_4&amp;=\dfrac{7 !}{(7-4) ! 4 !} \cdot \dfrac{6 !}{(6-4)}\\\
&amp;= 525\end{align}$8$$6$$7$$7$$6$$=7+6=13$$3,4,5,6$$6$\begin{align}{ }^7 C_2 \cdot{ }^6 C_6&amp;=\dfrac{7 !}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:48 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 Exercise 6.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-4-p3</link>
            <description>Question 3 Exercise 6.4

Solutions of Question 3 of Exercise 6.4 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$8$$8$$2^8$$$n(S)=256$$$$\dfrac{1}{256}$$$8$$$A=\{8\}$$$${ }^8 C_8=\dfrac{8 !}{(8-8) ! 8 !}=1$$$8$$$P(A)=\dfrac{1}{256}$$$7$$8$$2^8$$$n(S)=256$$$$\dfrac{1}{256}$$$7$$$B=\{7\}$$$7$$8$$$n(B)={ }^8 C_7=\dfrac{8 !}{(8-7) ! 7 !}=8$$$7$$8$$$P(B)=\d…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:51 +0000</pubDate>
        </item>
        <item>
            <title>Question 6 Exercise 6.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-4-p6</link>
            <description>Question 6 Exercise 6.4

Solutions of Question 6 of Exercise 6.4 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$52$$$=52$$$=4$$$=\dfrac{4}{52}=\dfrac{1}{13}$$$52$$=52$$13$$13$$$\dfrac{13}{52}+ \dfrac{13}{52}=\dfrac{1}{4}+\dfrac{1}{4}=\dfrac{2}{4}=\dfrac{1}{2}$$$52$$=52$$13.$$$=\dfrac{13}{52}=\dfrac{1}{4}$$$52$$=52$$12.$$$=\dfrac{12}{52}=\dfrac{3}{13}$…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:53 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 Exercise 6.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-5-p6</link>
            <description>Question 9 Exercise 6.5

Solutions of Question 9 of Exercise 6.5 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$2$$\dfrac{1}{7}$$\dfrac{1}{5}$\begin{align}
P(\text { Ajmal scicction })&amp;=\dfrac{1}{7} \\
\Rightarrow P(\text { Ajmal not selected })&amp;=\dfrac{6}{7} \\
P(\text { Bushra selection })&amp;=\dfrac{1}{5} \\
\Rightarrow P(\text { Bushra not selected }…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:57 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 &amp; 8 Review Exercise 6</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/re-ex6-p5</link>
            <description>Question 7 &amp; 8 Review Exercise 6

Solutions of Question 7 &amp; 8 of Review Exercise 6 of Unit 06: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$P(A)=0.8, P(B)=0.5$$P(B / A)=0.4$$P(A \cap B)$\begin{align}
P(B \mid A)&amp;=\dfrac{P(A \cap B)}{P(A)} \\
\Rightarrow P(A \cap B)&amp;=P(B \mid A) \cdot P(A)\\
&amp;=0.4 \times 0.8=0.32\end{align}$P(A)=0.8, P(B)=0.5$$P(B / A)=0.4$$P(A …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:01 +0000</pubDate>
        </item>
        <item>
            <title>Question 7 Exercise 7.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-2-p7</link>
            <description>Question 7 Exercise 7.2

Solutions of Question 7 of Exercise 7.2 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$(2+\sqrt{3})^5+(2-\sqrt{3})^5$\begin{align}(2+\sqrt{3})^5+(2 \cdot \sqrt{3})^5&amp; =[(2)^5+{ }^5 C_1 \cdot 2^4 \cdot \sqrt{3}+{ }^5 C_2 \cdot 2^3 \cdot(\sqrt{3})^2 \\
&amp; +^5 C_3 \cdot 2^2 \cdot(\sqrt{3})^4+{ }^5 C_4 \cdot 2 \cdot(\sqrt{3})^4 \\
…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:27 +0000</pubDate>
        </item>
        <item>
            <title>Question 3, Exercise 10.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/ex10-1-p3</link>
            <description>Question 3, Exercise 10.1

Solutions of Question 3 of Exercise 10.1 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\sin u=\dfrac{3}{5}$$\sin v=\dfrac{4}{5}$$u$$v$$0$$\dfrac{\pi }{2}$$\cos \left( u+v \right)$$\sin u=\dfrac{3}{5},$$0\le u\le \dfrac{\pi }{2}.$$\sin v=\dfrac{4}{5},$$0\le v\le \dfrac{\pi }{2}.$$\cos u=\pm \sqrt{1-{{\sin }^…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:40 +0000</pubDate>
        </item>
        <item>
            <title>Question 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>
        </item>
        <item>
            <title>Question 8 and 9, Exercise 10.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/ex10-2-p7</link>
            <description>Question 8 and 9, Exercise 10.2

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

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

Solutions of Question 2 of Exercise 10.3 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$$\sin {{37}^{\circ }}+\sin {{43}^{\circ }}.$$$$\sin \alpha +\sin \beta =2\sin \left( \dfrac{\alpha +\beta }{2} \right)\cos \left( \dfrac{\alpha -\beta }{2} \right).$$$\alpha ={{37}^{\circ }}$$\beta ={{43}^{\circ }}$\begin…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:46:02 +0000</pubDate>
        </item>
        <item>
            <title>Question 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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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            <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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            <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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>
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        <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 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>
        </item>
        <item>
            <title>Question 9, Exercise 2.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-1-p8</link>
            <description>Question 9, Exercise 2.1

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

Question 9(i)
$A=\begin{bmatrix}2 &amp; -1 &amp; 3  \\1 &amp; \quad 0 &amp; 1 \end{bmatrix},$$B=\begin{bmatrix}1 &amp; 2  \\2 &amp; 2  \\ 3 &amp; 0 \end{bmatrix}$$( AB )^t=B^tA^t$$$A=\left[  \begin{matrix}
   2 &amp; -1 &amp; 3  \\
   1 &amp; \quad 0 &amp; 1  \\
\end{matrix}  \right],$$$$B=\left[…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:17 +0000</pubDate>
        </item>
        <item>
            <title>Question 12, Exercise 2.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-1-p11</link>
            <description>Question 12, Exercise 2.1

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

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

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

Question 13(i)
$A$$3$$A+A^t$$$A=\left[ \begin{matrix}
   a_{11} &amp; a_{12} &amp; a_{13}  \\
   a_{21} &amp; a_{22} &amp; a_{23}  \\
   a_{31} &amp; a_{32} &amp; a_{33}  \\
\end{matrix} \right]$$$$A^t=\left[ \begin{matrix}
   a_{11} &amp; a_{21} &amp; a_{31}  \\
   a_{12} &amp; a_{22} …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:12 +0000</pubDate>
        </item>
        <item>
            <title>Question 7, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-2-p7</link>
            <description>Question 7, Exercise 2.2

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

Question 7(i)
$\left| \begin{matrix}3860 &amp; 3861  \\3862 &amp; 3863 \end{matrix} \right|$$$\left| \begin{matrix}
   3860 &amp; 3861  \\
   3862 &amp; 3863  \\
\end{matrix} \right|=14911180-14911182$$$$=-2$$$\left| \begin{matrix}81 &amp; 82 &amp; 83  \\84 &amp; 85 &amp; 86  \\87 &amp; 8…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:26 +0000</pubDate>
        </item>
        <item>
            <title>Question 14 &amp; 15, Exercise 2.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-2-p12</link>
            <description>Question 14 &amp; 15, Exercise 2.2

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

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

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

Question 18(i)
$A$$B$$( A^{-1})^{-1}=A$$A$$2\times 2$$$A=\left[ \begin{matrix}
   a_{11} &amp; a_{12}  \\
   a_{21} &amp; a_{22}  \\
\end{matrix} \right]$$$$|A|=a_{11}a_{22}-a_{12}a_{21}$$$$AdjA=\left[ \begin{matrix}
   a_{22} &amp; -a_{12}  \\
   -a_{21} &amp; a_{11…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:21 +0000</pubDate>
        </item>
        <item>
            <title>Question 3, Exercise 2.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit02/ex2-3-p3</link>
            <description>Question 3, Exercise 2.3

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

Question 3(i)
$$\left[ \begin{matrix}
   1 &amp; 0 &amp; -2  \\
   2 &amp; 2 &amp; 1  \\
   -1 &amp; 2 &amp; 3  \\
\end{matrix} \right]$$\begin{align}&amp;\begin{bmatrix}
1 &amp; 0 &amp; -2  \\
2 &amp; 2 &amp; 1  \\
-1 &amp; 2 &amp; 3 \end{bmatrix}\\
\underset{\sim}{R}&amp; \begin{bmatrix}
1 &amp; 0 &amp; -2  \\
0 &amp;…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:30 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 &amp; 4, Exercise 3.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-2-p3</link>
            <description>Question 3 &amp; 4, Exercise 3.2

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

Question 3

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

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

Question 5

Find the length of the vector $\overrightarrow{AB}$$\vec{A}(-3,5)$$\vec{B}(7,9)$$\overrightarrow{AB}$$\vec{A}$$\vec{B}$$$\overrightarrow{OA}=-3\hat{i}+5\hat{j},$$$$\overrightarrow{OB}=7\hat{i}+9\hat{j}.$$\begin{align}\overrightarrow{AB}&amp;=\overrightarr…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:31 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 &amp; 10, Exercise 3.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-2-p7</link>
            <description>Question 9 &amp; 10, Exercise 3.2

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

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

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

Question 11(i)

Find the position vectors of the point of division of the line segments joining point $C$$5\hat{j}$$D$$4\hat{i}+\hat{j}$$2:5$$C$$\overrightarrow{OC}=5\hat{j}$$D$$\overrightarrow{OD}=4\hat{i}+\hat{j}$$H$$\overline{CD}$$2:5$$H$\begin{align}\overrightarrow…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:35 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 and 5 Exercise 3.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-3-p3</link>
            <description>Question 4 and 5 Exercise 3.3

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

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

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

Question 6(i)

Let $\vec{a}=\hat{i}+3 \hat{j}-4 \hat{k}$ and $\vec{b}=2 \hat{i}-3 \hat{j}-5 \hat{k}$$m$$\vec{a}+m \vec{b}$$\vec{a}$\begin{align}
\vec{a}+m \vec{b}&amp; =\hat{i}+3 \hat{j}-4 \hat{k}+m(2 \hat{i}-3 \hat{j}+5 \hat{k}) \\
&amp; =(1+2 m) \hat{i}+(3-3 m) \hat{j}+(5 m-4) …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:38 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 &amp; 10, Exercise 3.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-3-p6</link>
            <description>Question 9 &amp; 10, Exercise 3.3

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

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

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

Question 11 (i)

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

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

Question 12
$\overrightarrow{B A} \cdot \overrightarrow{A C}=0$$|\vec{a}|=\vec{b}|=| \vec{c} \mid=$$\vec{b}=-\vec{c}$$\triangle A B O$\begin{align}\overrightarrow{O B}+\overrightarrow{A B}&amp;=\overrightarrow{O A}\\
\Rightarrow \overrightarrow{B A}&amp;=\overrightar…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:41 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 Exercise 3.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-4-p2</link>
            <description>Question 2 Exercise 3.4

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

Question 2(i)

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

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

Question 3(i)

Find a unit vector that is orthogonal to
the given vector $\vec{a}=\hat{i}- 2 \hat{j}+3 \hat{k}, \quad \vec{b}=2 \hat{i}+\hat{j}-\hat{k}$$\hat{n}$$\vec{a}$$\vec{b}$\begin{align}\hat{n}&amp;=\dfrac{\vec{a} \times \vec{b}}{\mid \vec{a} \times \vec{b}} \\
\text { …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:43 +0000</pubDate>
        </item>
        <item>
            <title>Question 5 Exercise 3.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-4-p5</link>
            <description>Question 5 Exercise 3.4

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

Question 5(i)

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

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

Question 6(i)

A force $\vec{F}=3 \hat{i}-2 \hat{j}+5 \hat{k}$$(1,-2,2)$$\vec{r}$$P(1,-2.2)$$O(0,0,0)$\begin{align}\vec{r}&amp;=\overrightarrow{O P}\\
&amp;=(1,-2,2)-(0,0,0) \\
\Rightarrow \vec{r}&amp;=(1,-2,2).\\
\text { Hence } \vec{M}-\vec{r} \times \vec{F}&amp;=\left|\begin{array}{cc…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:46 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 Exercise 3.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-4-p8</link>
            <description>Question 9 Exercise 3.4

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

Question 9(i)

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

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

Question 1

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

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

Question 3

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

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

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

Solutions of Question 5(iii) &amp; 5(iv) of Exercise 3.5 of Unit 03: Vectors. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\vec{a}=a_1 \hat{i}+a_2 \hat{j}+a_3 \hat{k}\quad$$\quad\vec{b}=b_1 \hat{i}+b_2 \hat{j}+b_3 \hat{k}\quad$$(\vec{a}. \vec{b})^2,\quad|a|^2,\quad|b|^2$\begin{align}\vec{a} \cdot \vec{b}&amp;=(a_1 \hat{i}+a_2 \hat{j} + a_3 \hat{k}) \cdot(b_1 \hat{i}+b_2 \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:50 +0000</pubDate>
        </item>
        <item>
            <title>Question 8 Exercise 3.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/ex3-5-p7</link>
            <description>Question 8 Exercise 3.5

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

Question 8(i)

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

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

Question 9 (i)

Write the value of $(\hat{i} \times \hat{j}). \hat{k}+\hat{i}. \hat{j}$\begin{align}
(\hat{i} \times \hat{j}) \cdot \hat{k}&amp;=\left|\begin{array}{ccc}
1 &amp; 0 &amp; 0 \\
0 &amp; 1 &amp; 0 \\
0 &amp; 0 &amp; 1
\end{array}\right|&amp;=1 ....(1)\\
\text { and } \hat{i} \cdot \hat{j}&amp;=0…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:53 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 &amp; 3 Review Exercise 3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit03/review-ex3-p2</link>
            <description>Question 2 &amp; 3 Review Exercise 3

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

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

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

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

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

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

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

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

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

Question 10(i)
$A B C$$|\vec{a}|^2=|\vec{b}|^2+|\vec{c}|^2 -2|\vec{b}|| \vec{c}| \cos A$$A B C$$\vec{a}, \vec{b}$$\vec{c}$\begin{align}
\vec{b}&amp;=\vec{a}+\vec{c} \\
\Rightarrow \vec{a}&amp;=\vec{b}-\vec{c} \\
\Rightarrow \vec{a} \cdot \vec{a}&amp;=(\vec{b}-\vec{c}) \cd…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Wed, 03 Jan 2024 18:10:58 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 and 2 Exercise 4.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-2-p1</link>
            <description>Question 1 and 2 Exercise 4.2

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

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

Solutions of Question 5 and 6 of Exercise 4.2 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$$\log a, \log (a b), \log \left(a b^2\right), \log \left(a b^3\right), \ldots$$$n$$\log$$a$$b$$b$$$a_n=\log (a b^{n-1}).$$\begin{align}a_n&amp;=\log(a b^{n-1}). \end{align}\begin{align}
d&amp;=a_{n+1}-a_n \\
&amp;=\log (a b^n)-\log (a b^{n-1}) \\
&amp;=\log \left(\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 10 Feb 2024 16:55:28 +0000</pubDate>
        </item>
        <item>
            <title>Question 14 Exercise 4.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-2-p10</link>
            <description>Question 14 Exercise 4.2

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

Question 14(i)
$A_1, A_2, A_3$$6, A_1, A_2, A_3, 41$$$a_1=6 \text{ and } a_6=41.$$\begin{align}&amp; a_5=11\\
\Rightarrow &amp;a_1+4 d=41 \\
\Rightarrow &amp;6+4 d=41 \\
\Rightarrow &amp;d=\dfrac{41-6}{4}\\
&amp;=\dfrac{35}{4}.\end{align}\begin{align} A_1&amp;=a+d=6+\dfrac{35}{4} \…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 11 Feb 2024 10:45:10 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 Exercise 4.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-3-p1</link>
            <description>Question 1 Exercise 4.3

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

Question 1(i)
$9,7,5,3, \ldots$$a_1$$d$\begin{align}&amp;a_1=9 \\ 
&amp;d=7-9=-2 \\
&amp;n=20.
\end{align}\begin{align}&amp;a_n=a_1+(n-1)d \\
\implies &amp;a_20=9+(20-1)(-2)=-29.
\end{align}$S_n$$n$\begin{align}
S_n&amp;=\dfrac{n}{2}[a_1+a_n], \\
\implies S_{20}&amp;=\dfrac{20}{2}[9-29] …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 11 Feb 2024 11:01:45 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 &amp; 4 Exercise 4.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-3-p3</link>
            <description>Question 3 &amp; 4 Exercise 4.3

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

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

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

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

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

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

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

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

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

Solutions of Question 13 &amp; 14 of Exercise 4.3 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.\begin{align}\text{Total number of rows}&amp; n=40,\\
\text{Seats in a first row} a_1&amp;=20\\
\text{Seat in a second row} a_2&amp;=23\\
\text{Seats in third row} a_3&amp;=26\end{align}$20,23,26, \ldots$$S_{40}$$$S_n=\dfrac{n}{2} [{2} a_1+(n-1) d] \text {.}$$\begin…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:29:58 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 &amp; 3 Exercise 4.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-4-p2</link>
            <description>Question 2 &amp; 3 Exercise 4.4

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

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

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

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

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

Question 6
$a_{10}=l, a_{13}=m$$a_{16}=n;\quad$$\ln =m^2$$a_n=a_1 r^{n-1}$\begin{align}a_{10}&amp;=a_1 r^9=l \\
a_{13}&amp;=a_1 r^{12}=m\\
\text{and} \quad a_{16}&amp;=a_1 e^{\mathbf{A 5}}=n\end{align}\begin{align}a_{10} \cdot a_{16}&amp;=\ln =(a_1 r^9)(a_1 r^{15})\\
…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:30:01 +0000</pubDate>
        </item>
        <item>
            <title>Question 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>
        </item>
        <item>
            <title>Question 7 &amp; 8 Exercise 4.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-5-p6</link>
            <description>Question 7 &amp; 8 Exercise 4.5

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

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

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

Question 9
$9$$n$$r$$a_1$$$S_n=\dfrac{a_1[r^n-1]}{r-1}$$$$S_6=\dfrac{a_1(r^5-1)}{r-1}$$$$S_3=\dfrac{a_1(r^3-1)}{r-1} \text {. }$$$3$$9$$6$\begin{align} \dfrac{a_1(r^6-1)}{r-1}&amp;=9 \dfrac{a_1(r^3-1)}{r-1} \\
\Rightarrow r^6-1-9(r^3-1) \\
\Rightarrow r^…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:30:12 +0000</pubDate>
        </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>
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        <item>
            <title>Question 15 &amp; 16 Exercise 4.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-5-p10</link>
            <description>Question 15 &amp; 16 Exercise 4.5

Solutions of Question 15 &amp; 16 of Exercise 4.5 of Unit 04: Sequence and Series. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$2$$4$$15^{\text {th }}$$a_1=R s .1$$a_2=R s .2$$a_3=R s .4$$1,2,4,8, \ldots$$a_1=1 . \quad r=2 . \quad n=15$$a_n=a_1 r^{n-1}$$15^{1 / 2}$$$a_{15}=a_1 r^{14} $$$$a_{15}=1 .(2)^{1 4}=R s .16384 $$$$S_{30}=\dfrac{a_1(r^{30}-1)}{r-1} $$$r-2$$a_1=1$\begi…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:30:06 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 &amp; 3 Exercise 5.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/ex5-1-p2</link>
            <description>Question 2 &amp; 3 Exercise 5.1

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

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

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

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

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

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

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

Question 9(i)
$n$$n$$n$\begin{align}
&amp; T_n=n^2(2 n+3)=2 n^3+3 n^2 \\
&amp; \Rightarrow T_j=2 j^3+3 j^2\end{align}\begin{align}
&amp; \sum_{j=1}^n T_j=2 \sum_{j=1}^n j^3+3 \sum_{j=1}^n j^2 \\
&amp; =2(\dfrac{n(n+1)}{2})^2+3 \dfrac{n(n+1)(2 n+1)}{6} \\
&amp; =\dfrac{n(n+1)}{2}…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:13 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 &amp; 3 Exercise 5.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/ex5-2-p2</link>
            <description>Question 2 &amp; 3 Exercise 5.2

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

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

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

Question 4
$5+\dfrac{7}{3}+\dfrac{9}{3^2}+\dfrac{11}{3^3}+\ldots$\begin{align}
&amp; S_{\infty}=5+\dfrac{7}{3}+\dfrac{9}{3^2}+\dfrac{11}{3^3}+\ldots.(i) \\
&amp; \dfrac{1}{3} S_{\infty}=\dfrac{5}{3}+\dfrac{7}{3^2}+\dfrac{9}{3^2}+\dfrac{11}{3^3}+\ldots.(ii)
\e…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:15 +0000</pubDate>
        </item>
        <item>
            <title>Question 2 &amp; 3 Exercise 5.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/ex5-4-p2</link>
            <description>Question 2 &amp; 3 Exercise 5.4

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

Question 2
$\sum_{k=1}^n \dfrac{1}{9 k^2+3 k-2}$\begin{align}\text { Let } S_n&amp;=\sum_{k=1}^n \dfrac{1}{9 k^2+3 k-2} \\
S_n&amp;=\sum_{k=1}^n \dfrac{1}{9 k^2+6 k-3 k-2} \\
&amp; =\sum_{k=1}^n \dfrac{1}{3 k(3 k+2)-1(3 k+2)} \\
S_n&amp;=\sum_{k=1}^n \dfrac{1}{(3 k-1…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:21 +0000</pubDate>
        </item>
        <item>
            <title>Question 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>
        </item>
        <item>
            <title>Question 7 and 8 Exercise 7.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-3-p6</link>
            <description>Question 7 and 8 Exercise 7.3

Solutions of Question 7 and 8 of Exercise 7.3 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$x^4$$(1-x)^{\frac{1}{4}}+(1-x)^{\frac{1}{4}}=a-b x^2$$a$$b$$$
\begin{aligned}
&amp; (1+x)^{\frac{1}{4}}+(1-x)^{\frac{1}{4}} \\
&amp; =\left[1+\frac{x}{4}+\frac{\frac{1}{4}\left(\frac{1}{4}-1\right)}{2 !} x^2+\right. \\
&amp; \left.\frac{\fra…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:35 +0000</pubDate>
        </item>
        <item>
            <title>Question 10 Exercise 7.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit07/ex7-3-p8</link>
            <description>Question 10 Exercise 7.3

Solutions of Question 10 of Exercise 7.3 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$1-\frac{1}{2^2}+\frac{1.3}{2 !} \cdot \frac{1}{2^4}+\ldots$$(1+x)^n$$$
\begin{aligned}
&amp; 1+n x+\frac{n(n-1)}{2 !} x^2 \\
&amp; +\frac{n(n-1(n-2))}{3 !} x^3+\ldots
\end{aligned}
$$$n x=-\frac{1}{4}$$\frac{n(n-1)}{2 !} x^2=\frac{1.3}{2 !} \cdot …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:36:37 +0000</pubDate>
        </item>
        <item>
            <title>Question 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>
        </item>
        <item>
            <title>Question 6, Exercise 10.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit10/ex10-1-p6</link>
            <description>Question 6, Exercise 10.1

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

Solutions of Question 1 of Exercise 10.1 of Unit 10: Trigonometric Identities of Sum and Difference of Angles. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.$\cot \left( \alpha +\beta  \right)=\dfrac{\cot \alpha \cot \beta -1}{\cot \alpha +\cot \beta }$\begin{align}L.H.S.&amp;=\cot (\alpha +\beta )\\
&amp;=\dfrac{1}{\tan (\alpha +\beta )}\\
&amp;=\dfrac{1}{\,\dfrac{\tan \alpha +\tan \beta…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Tue, 05 Dec 2023 02:45:44 +0000</pubDate>
        </item>
        <item>
            <title>Question 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-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>
        </item>
        <item>
            <title>Question 7 Exercise 4.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-2-p4</link>
            <description>Question 7 Exercise 4.2

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

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

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

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

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

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

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

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

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

Question 11
$a_1$$$a_1=1000.$$$= d=100$$a_n=5400$$n$\begin{align}
&amp;a_n=a_1+(n-1)d \\
 \implies &amp;5400=1000+(n-1)100\\
 \implies &amp;5400=900+100n \\
 \implies &amp;100n=5400-900\\
 \implies &amp;100n=4500\\
 \implies &amp;n=45.\end{align}</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sat, 10 Feb 2024 18:43:43 +0000</pubDate>
        </item>
        <item>
            <title>Question 15 Exercise 4.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-2-p11</link>
            <description>Question 15 Exercise 4.2

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

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

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

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

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

Question 17
$n$$7: 13$$n$$A_1, A_2, A_3, \ldots, A_n$$n$$5, A_1, A_2, A_3, \ldots, A_n, 32$$$a_1=5 \text{ and } a_{n+2}=32.$$$a_n=a_1+(n-1) d$$n$$n+2$\begin{align}a_{n+2}&amp;=a_1+(n+2-1) d \\
	&amp; =a_1+(n+1) d \\
	\implies 32&amp;=5+(n+1)d \\
	\implies (n+1)d&amp;=32-5\\…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Sun, 11 Feb 2024 10:39:35 +0000</pubDate>
        </item>
        <item>
            <title>Question 10 Exercise 4.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-4-p7</link>
            <description>Question 10 Exercise 4.4

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

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

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

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

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

Question 12
$n, . \dfrac{a^{n+1}+b^{n+1}}{a^n+b^n}$$a$$b$$a$$b$$\dfrac{a^{n+1}+b^{n-1}}{a^n+b^n}$$a$$b$\begin{align}\dfrac{a^{n+1}+b^{n+1}}{a^n+b^n}&amp;=\sqrt{a b}\quad \because G \cdot M=\sqrt{a b} \\
\Rightarrow \dfrac{a^{n+1}+b^{n+1}}{a^n+b^n}&amp;=a^{\dfrac{1}{…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:30:05 +0000</pubDate>
        </item>
        <item>
            <title>Question 3 Exercise 4.5</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit04/ex4-5-p3</link>
            <description>Question 3 Exercise 4.5

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

Question 3
$a_2=2$$a_3=1$$a_1$$r$$$a_n=a_1 r^{n-1}$$$$a_2=a_1 r=2....(i)$$$$a_3=a_1 r^2=1...(ii)$$\begin{align}\dfrac{a_1 r^2}{a_1 r}&amp;=\dfrac{1}{2}\\
\Rightarrow r&amp;=\dfrac{1}{2} \text {, }\end{align}\begin{align}\dfrac{a_1}{2}&amp;=2\\
\Rightarrow a_1&amp;=4 \text {. …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Fri, 05 Jan 2024 17:30:08 +0000</pubDate>
        </item>
        <item>
            <title>Question 6 Exercise 5.1</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/ex5-1-p4</link>
            <description>Question 6 Exercise 5.1

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

Question 6
$1.2 \cdot 3+2 \cdot 3.4+3.4 .5+\ldots$$n$$1+2+3+\ldots, \quad 2+3+4+5+\ldots$$3+4+5+6+7+\ldots$$n^{t h}$$j, j+1$$j+2$$n^{t h}$\begin{align}
&amp; T_j=j(j+1)(j+2)-j(j^2+3 j+2) \\
&amp; =j^3+3 j^2+2 j\end{align}\begin{align}
&amp; \sum_{j=1}^n T_j=\sum_{j=1}^n …</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:12 +0000</pubDate>
        </item>
        <item>
            <title>Question 1 Exercise 5.3</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/ex5-3-p1</link>
            <description>Question 1 Exercise 5.3

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

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

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

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

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

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

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

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

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

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

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

Question 6
$n$$n$$28+32+52+152+652+\ldots$\begin{align}
&amp; a_2-a_1=32-28=4 \\
&amp; a_3-a_2=52-32=20 \\
&amp; a_4-a_3=152-52=100 \\
&amp; \ldots \quad \cdots \quad \cdots \\
&amp; \cdots \quad \cdots \quad \cdots \\
&amp; a_n-a_{n-1}=(\mathrm{n}-1) \text { term ofthe sequence } 4…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:20 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 Exercise 5.4</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/ex5-4-p3</link>
            <description>Question 4 Exercise 5.4

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

Question 4
$\sum_{k=1}^n \dfrac{1}{k^2+7 k+12}$\begin{align}S_n &amp;=\sum_{k=1}^n \dfrac{1}{k^2+7 k+12} \\
&amp; =\sum_{k=1}^n \dfrac{1}{(k+3)(k+4)}\end{align}$n^{\text {th }}$$$u_n=\dfrac{1}{(n+3)(n+4)}$$$$\dfrac{1}{(n+3)(n+4)}=\dfrac{A}{n+3}+\dfrac{B}{n+4}$$$A$$B$…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:21 +0000</pubDate>
        </item>
        <item>
            <title>Question 4 Review Exercise</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/re-ex5-p3</link>
            <description>Question 4 Review Exercise

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

Question 4
$\dfrac{1}{1.4 .7}+\dfrac{1}{4.7 .10}+\dfrac{1}{7.10 .13}+\ldots$$1,4,7, \ldots$$$a_n=\dfrac{1}{(3 n-2)(3 n+1)(3 n+4)}$$\begin{align}
\dfrac{1}{(3 n-2)(3 n+1)(3 n+4)}&amp;=\dfrac{A}{3 n-2}+\dfrac{B}{3 n+1}+\dfrac{C}{3 n+4}\end{align}$(3 n-2)(3 n+…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:24 +0000</pubDate>
        </item>
        <item>
            <title>Question 10 Review Exercise</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit05/re-ex5-p8</link>
            <description>Question 10 Review Exercise

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

Question 10
$n^{\text {th }}$$n$$1+(1+\dfrac{1}{2})+(1+\dfrac{1}{2}+\dfrac{1}{4})+(1+\dfrac{1}{2}+\dfrac{1}{4}+\dfrac{1}{8})+\ldots$\begin{align}
a_n&amp;=1+\dfrac{1}{2}+\dfrac{1}{4}+\dfrac{1}{8}+\cdots+\dfrac{1}{2^{n-1}} \\
a_n&amp;=\dfrac{1[1-(\dfrac{1}{2})…</description>
            <author>anonymous@undisclosed.example.com (Anonymous)</author>
            <pubDate>Thu, 01 Feb 2024 02:35:26 +0000</pubDate>
        </item>
        <item>
            <title>Question 9 Exercise 6.2</title>
            <link>https://www.mathcity.org/math-11-kpk/sol/unit06/ex6-2-p5</link>
            <description>Question 9 Exercise 6.2

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