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        <title>Question 1, Exercise 1.3</title>
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        <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>
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        <title>Question 11, Exercise 1.1</title>
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        <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>
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        <title>Question 1, Exercise 1.1</title>
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        <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>
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        <title>Question 5, Exercise 1.1</title>
        <link>https://beta.mathcity.org/fsc-part1-kpk/sol/unit01/ex1-1-p4?rev=1737476036&amp;do=diff</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>
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        <title>Question 2, Exercise 10.2</title>
        <link>https://beta.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-2-p2?rev=1737476036&amp;do=diff</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>
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        <title>Question 6, Exercise 10.2</title>
        <link>https://beta.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-2-p5?rev=1737476036&amp;do=diff</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>
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        <title>Question 2 &amp; 3, Exercise 1.1</title>
        <link>https://beta.mathcity.org/fsc-part1-kpk/sol/unit01/ex1-1-p2?rev=1737476036&amp;do=diff</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>
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        <title>Question 5, Exercise 1.3</title>
        <link>https://beta.mathcity.org/fsc-part1-kpk/sol/unit01/ex1-3-p4?rev=1737476036&amp;do=diff</link>
        <description>Question 5, Exercise 1.3

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

Question 5(i)
${{z}^{2}}+z+3=0$${{z}^{2}}+z+3=0$$a=1,\,\,\,b=1$$c=3$\begin{align}z&amp;=\dfrac{-b\pm \sqrt{{{b}^{2}}-4ac}}{2a}\\ 
z&amp;=\dfrac{-\left( 1 \right)\pm \sqrt{{{\left( 1 \right)}^{2}}-4\left( 1 \right)\left( 3 \right)}}{2\left( 1 \right)}\\
z&amp;=\dfrac{-1\pm \s…</description>
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        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Unit 1: Complex Numbers (Solutions)</title>
        <link>https://beta.mathcity.org/fsc-part1-kpk/sol/unit01?rev=1737476036&amp;do=diff</link>
        <description>Unit 1: Complex Numbers (Solutions)

This is a first unit of the book Mathematics 11 published by Khyber Pakhtunkhwa Textbook Board, Peshawar, Pakistan. On this page we have provided the solutions of the questions.

After reading this unit the students will be able to$z$$z=a+ib$$(a,b)$$a$$b$$i=\sqrt{-1}$$a$$z$$b$$z$$\bar{z} = a —ib$$z=a+ib$$|z| = \sqrt{a^2+b^2}$$z=a+ib$$&#039;+&#039;$$&#039;\times&#039;$$z$$|z|=|-z|=|\bar{z}=|-\bar{z}|$$pz^2+ qz+ r = 0$$p,q,r$$z$</description>
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        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Unit 10: Trigonometric Identities of Sum and Difference of Angles (Solutions)</title>
        <link>https://beta.mathcity.org/fsc-part1-kpk/sol/unit10?rev=1737476036&amp;do=diff</link>
        <description>Unit 10: Trigonometric Identities of Sum and Difference of Angles (Solutions)

This is a tenth unit of the book Mathematics 11 published by Khyber Pakhtunkhwa Textbook Board, Peshawar, Pakistan. On this page we have provided the solutions of the questions.$a\sin\theta + b\cos \theta$$r\sin(\theta +\psi )$$a = r\cos\psi$$b=r\sin\psi$</description>
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        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Question11 and 12, Exercise 10.1</title>
        <link>https://beta.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-1-p10?rev=1737476036&amp;do=diff</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>
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        <dc:date>2025-01-21T16:13:56+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Definitions: FSc Part1 KPK</title>
        <link>https://beta.mathcity.org/fsc-part1-kpk/definitions?rev=1737476036&amp;do=diff</link>
        <description>Definitions: FSc Part1 KPK

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

Definition of the book provide the quick overview of the book.$360^\circ$$\theta$$90^{\circ} \pm \theta, 180^{\circ} \pm \theta, 270^{\circ} \pm \theta, 360^{\circ} \pm \theta$$16^\circ 13&#039; 9&#039;&#039;$$sin(\alpha+2\pi)=sin\alpha$$sin x=\frac{2}{7}$$cos x-tan x=0$</description>
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        <dc:date>2025-01-21T16:13:56+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Important Questions</title>
        <link>https://beta.mathcity.org/fsc-part1-kpk/important-questions?rev=1737476036&amp;do=diff</link>
        <description>Important Questions

This page will be updated soon.
&lt;list-group&gt;

	*  Prove that (without calculator) $\sin 10^{\circ}\sin 30^{\circ}\sin 50^{\circ}\sin 70^{\circ}=\frac{1}{16}$ ---  BISE Gujrawala(2015)
	*  Prove that $\sin(\frac{\pi}{4}-\theta)\sin(\frac{\pi}{4}+\theta)=\frac{1}{2}\csc^2\theta$ ---  BISE Gujrawala(2017)
	*  Prove that $\sin(\theta+\frac{\pi}{6})=\cos\theta$ ---  BISE Gujrawala(2017)
	*  Using without table or calculator find $tan(1110^{\circ})$$sin(180^{\circ}+\alpha)sin(90^{…</description>
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        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Question 8, Exercise 1.1</title>
        <link>https://beta.mathcity.org/fsc-part1-kpk/sol/unit01/ex1-1-p7?rev=1737476036&amp;do=diff</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>
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        <dc:date>2025-01-21T16:13:56+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Question 9 &amp; 10, Exercise 1.1</title>
        <link>https://beta.mathcity.org/fsc-part1-kpk/sol/unit01/ex1-1-p8?rev=1737476036&amp;do=diff</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>
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        <dc:date>2025-01-21T16:13:56+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Question, Exercise 10.1</title>
        <link>https://beta.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-1-p4?rev=1737476036&amp;do=diff</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>
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        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Question 9 and 10, Exercise 10.1</title>
        <link>https://beta.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-1-p9?rev=1737476036&amp;do=diff</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>
    </item>
    <item rdf:about="https://beta.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-1-p11?rev=1737476036&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2025-01-21T16:13:56+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Question 13, Exercise 10.1</title>
        <link>https://beta.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-1-p11?rev=1737476036&amp;do=diff</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>
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    <item rdf:about="https://beta.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-3-p2?rev=1737476036&amp;do=diff">
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        <dc:date>2025-01-21T16:13:56+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Question 2, Exercise 10.3</title>
        <link>https://beta.mathcity.org/fsc-part1-kpk/sol/unit10/ex10-3-p2?rev=1737476036&amp;do=diff</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>
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