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        <dc:date>2025-01-21T16:13:59+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Question 9 Exercise 7.2</title>
        <link>https://beta.mathcity.org/math-11-kpk/sol/unit07/ex7-2-p9?rev=1737476039&amp;do=diff</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>
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        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Question 10 Exercise 7.3</title>
        <link>https://beta.mathcity.org/math-11-kpk/sol/unit07/ex7-3-p8?rev=1737476039&amp;do=diff</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>
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        <dc:date>2025-01-21T16:13:58+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Question 12 Exercise 7.1</title>
        <link>https://beta.mathcity.org/math-11-kpk/sol/unit07/ex7-1-p12?rev=1737476038&amp;do=diff</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>
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        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Question 1 Exercise 7.3</title>
        <link>https://beta.mathcity.org/math-11-kpk/sol/unit07/ex7-3-p1?rev=1737476039&amp;do=diff</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>
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        <dc:date>2025-01-21T16:13:59+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Question 2 Review Exercise 7</title>
        <link>https://beta.mathcity.org/math-11-kpk/sol/unit07/re-ex7-p2?rev=1737476039&amp;do=diff</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>
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        <dc:date>2025-01-21T16:13:59+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Question 12 Exercise 7.3</title>
        <link>https://beta.mathcity.org/math-11-kpk/sol/unit07/ex7-3-p10?rev=1737476039&amp;do=diff</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>
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        <dc:date>2025-01-21T16:13:58+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Question 8 Exercise 7.1</title>
        <link>https://beta.mathcity.org/math-11-kpk/sol/unit07/ex7-1-p8?rev=1737476038&amp;do=diff</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>
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        <dc:date>2025-01-21T16:13:58+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Question 11 Exercise 7.1</title>
        <link>https://beta.mathcity.org/math-11-kpk/sol/unit07/ex7-1-p11?rev=1737476038&amp;do=diff</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>
    </item>
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        <dc:date>2025-01-21T16:13:58+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Question 13 Exercise 7.1</title>
        <link>https://beta.mathcity.org/math-11-kpk/sol/unit07/ex7-1-p13?rev=1737476038&amp;do=diff</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>
    </item>
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        <dc:date>2025-01-21T16:13:59+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Question 11 Exercise 7.3</title>
        <link>https://beta.mathcity.org/math-11-kpk/sol/unit07/ex7-3-p9?rev=1737476039&amp;do=diff</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>
    </item>
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        <dc:date>2025-01-21T16:13:59+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Question 13 Exercise 7.3</title>
        <link>https://beta.mathcity.org/math-11-kpk/sol/unit07/ex7-3-p11?rev=1737476039&amp;do=diff</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>
    </item>
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        <dc:format>text/html</dc:format>
        <dc:date>2025-01-21T16:13:59+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Question 1 Review Exercise 7</title>
        <link>https://beta.mathcity.org/math-11-kpk/sol/unit07/re-ex7-p1?rev=1737476039&amp;do=diff</link>
        <description>Question 1 Review Exercise 7

Solutions of Question 1 of Review Exercise 7 of Unit 07: Permutation, Combination and Probablity. This is unit of A Textbook of Mathematics for Grade XI is published by Khyber Pakhtunkhwa Textbook Board (KPTB or KPTBB) Peshawar, Pakistan.
Chose the correct option.
&lt;panel&gt;$O, P, Q, R, S, T, U$$2520$$9040$$5140$$4880$$\{1,2,3,4,5,6,7\}$$14$$42$$28$$21$$\{1,2,3,4,6,7,8\}$$3$$7$$120$$180$$144$$96$$\dfrac{(n+2) !(n-2) !}{(n+1) !(n-1) !}$$(n-3)$$(\dot{n}-1)$$\dfrac{n+1}{n…</description>
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