Merging man & maths https://www.mathcity.org/ Wed, 03 Jun 2026 20:20:58 +0000 FeedCreator 1.8 https://www.mathcity.org/_media/logo.svg https://www.mathcity.org/ https://www.mathcity.org/math-11-nbf/sol/unit09/ex9-1-p1 Question 1, Exercise 9.1 Solutions of Question 1 of Exercise 9.1 of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $y=2-2 \operatorname{Cos} \theta$\begin{align*} -1 \leq \operatorname{Cos} \theta \leq 1 \end{align*}$-2$\begin{align*} & 2 \geq -2 \operatorname{Cos} \theta \geq -2 \end{align*}$2$\begin{align*} & 4 \geq 2-2 \operatorname{Cos} \theta \geq 0 \\ … anonymous@undisclosed.example.com (Anonymous) Wed, 27 Nov 2024 15:59:09 +0000 https://www.mathcity.org/math-11-nbf/sol/unit09/ex9-1-p2 Question 2, Exercise 9.1 Solutions of Question 2 of Exercise 9.1 of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $y=\dfrac{1}{4+3 \operatorname{Sin} \theta}$\begin{align*} -1 \leq \operatorname{Sin} \theta \leq 1 \end{align*}$3$\begin{align*} -3 \leq 3 \operatorname{Sin} \theta \leq 3 \end{align*}$4$\begin{align*} & 1 \leq 4+3 \operatorname{Sin} \theta \l… anonymous@undisclosed.example.com (Anonymous) Wed, 27 Nov 2024 15:59:10 +0000 https://www.mathcity.org/math-11-nbf/sol/unit09/ex9-1-p3 Question 3, Exercise 9.1 Solutions of Question 3 of Exercise 9.1 of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $y=7 \cos 4x$\begin{align*} & -1\leq \cos 4x \leq 1 \,\, \forall \,\, x\in \mathbb{R} \\ \implies & -7\leq 7 \cos 4x \leq 7 \\ \end{align*}$= ]-\infty, \infty[ = \mathbb{R}$$=[-7,7]$$y=\cos \frac{x}{3}$\begin{align*} & -1\leq \cos \frac{x}{3} \… anonymous@undisclosed.example.com (Anonymous) Wed, 27 Nov 2024 15:59:11 +0000 https://www.mathcity.org/math-11-nbf/sol/unit09/ex9-1-p4 Question 4(i-iv), Exercise 9.1 Solutions of Question 4(i-iv) of Exercise 9.1 of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $y=\sin x+x \cdot \cos x$$f(x)=\sin x+x \cdot \cos x$\begin{align*} f(-x) = \sin (-x) + (-x)\cdot \cos (-x) \end{align*}$\sin(-x)=-\sin x$$\cos (-x) = \cos x$\begin{align*} f(x) & = -\sin x - x \cdot \cos x \\ & = -(\sin x + x \cdot … anonymous@undisclosed.example.com (Anonymous) Wed, 27 Nov 2024 15:59:11 +0000 https://www.mathcity.org/math-11-nbf/sol/unit09/ex9-1-p5 Question 4(v-viii), Exercise 9.1 Solutions of Question 4(v-viii) of Exercise 9.1 of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $y=\dfrac{\sin ^{2} x}{x+\tan x}$\[y = \frac{\sin^2 x}{x + \tan x}\]\begin{align*} y(-x) &= \frac{\big(-\sin x\big)^2}{-x - \tan x} \\ &= \frac{\sin^2 x}{-x - \tan x}\\ & = \frac{\sin^2 x}{-(x + \tan x)}\\ & = -\frac{\sin^2 x}{x +… anonymous@undisclosed.example.com (Anonymous) Wed, 27 Nov 2024 15:59:12 +0000 https://www.mathcity.org/math-11-nbf/sol/unit09/ex9-1-p6 Question 5(i-v), Exercise 9.1 Solutions of Question 5(i-v) of Exercise 9.1 of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $y=2 \operatorname{Sin} x$$y=2 \operatorname{Cos} 3 x$$y=2 \operatorname{Tan} 2 x$$\mathrm{y}=\operatorname{Cos} \frac{\mathrm{x}}{2}$ anonymous@undisclosed.example.com (Anonymous) Wed, 27 Nov 2024 15:59:13 +0000 https://www.mathcity.org/math-11-nbf/sol/unit09/ex9-1-p7 Question 5(vi-x), Exercise 9.1 Solutions of Question 5(vi-x) of Exercise 9.1 of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $y=2 \operatorname{Sin} 3 x$$y=3 \operatorname{Cos} x$$y=\operatorname{Cos}^{2} x$$y=\operatorname{Sin}^{2} x$$y=\operatorname{Tan}^{2} x$$y=\operatorname{Sin} \frac{x}{2}$ anonymous@undisclosed.example.com (Anonymous) Wed, 27 Nov 2024 15:59:14 +0000 https://www.mathcity.org/math-11-nbf/sol/unit09/ex9-1-p8 Question 6, Exercise 9.1 Solutions of Question 6 of Exercise 9.1 of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $y=6 \sec(2 x-3)$$\sec$$2\pi$\begin{align*} 6 \sec(2 x-3) & = 6 \sec(2 x-3+2\pi) \\ & = 6 \sec(2(x+\pi)-3) \end{align*}$6 \sec(2 x-3)$$\pi$$y=\cos (5 x+4)$$\cos$$2\pi$\begin{align*} \cos (5 x+4) & = 6 \cos(5x+4+2\pi) \\ & = \cos\left(5\left(x+\fr… anonymous@undisclosed.example.com (Anonymous) Wed, 27 Nov 2024 15:59:15 +0000 https://www.mathcity.org/math-11-nbf/sol/unit09/ex9-1-p9 Question 7 & 8, Exercise 9.1 Solutions of Question 7 & 8 of Exercise 9.1 of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $y=\operatorname{Sin} x$$y=\operatorname{Sin} 2 x$$[0,2 \pi]$$y=\operatorname{Cos} x$$y=\operatorname{Cos} 2 x$$[0,2 \pi]$ anonymous@undisclosed.example.com (Anonymous) Wed, 27 Nov 2024 15:59:15 +0000 https://www.mathcity.org/math-11-nbf/sol/unit09/ex9-1-p10 Question 9, Exercise 9.1 Solutions of Question 9 of Exercise 9.1 of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\sin x=\cos x$$\cos x=x$$\sin x=x$$\tan x=x$ anonymous@undisclosed.example.com (Anonymous) Wed, 27 Nov 2024 15:59:09 +0000 https://www.mathcity.org/math-11-nbf/sol/unit09/ex9-1-p11 Question 10, Exercise 9.1 Solutions of Question 10 of Exercise 9.1 of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $ V(t)=a \operatorname{Sin}(k(t-d))+c$$56 \mathrm{~Hz} A C$$k$ anonymous@undisclosed.example.com (Anonymous) Wed, 27 Nov 2024 15:59:10 +0000 https://www.mathcity.org/math-11-nbf/sol/unit09/re-ex-1-p2 Question 2 and 3,Review Exercise Solutions of Question 2 and 3 of Review Exercise of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. anonymous@undisclosed.example.com (Anonymous) Wed, 27 Nov 2024 15:59:17 +0000 https://www.mathcity.org/math-11-nbf/sol/unit09/re-ex-1-p3 Question 4, Review Exercise Solutions of Question 4 of Review Exercise of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. anonymous@undisclosed.example.com (Anonymous) Wed, 27 Nov 2024 15:59:18 +0000 https://www.mathcity.org/math-11-nbf/sol/unit09/re-ex-p1 Question 1,Review Exercise Solutions of Question 1 of Review Exercise of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\cos \theta=\frac{\sqrt{3}}{2}$$\sin \theta=$$\frac{1}{2}$$-\frac{1}{2}$$\sqrt{3}$$-\frac{2}{\sqrt{3}}$$-\frac{1}{2}$$\tan (-15 \pi)=$$ 0$$-1$$1$$0$$2 \sin \theta+\frac{1}{2}cosec \theta \theta $$\theta=45^{\circ}$$\frac{1}{\sqrt{2}}$$\frac… anonymous@undisclosed.example.com (Anonymous) Wed, 27 Nov 2024 15:59:18 +0000 https://www.mathcity.org/math-11-nbf/sol/unit09/re-ex-p2 Question 2 and 3, Review Exercise Solutions of Question 2 and 3 of Review Exercise of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\cos \theta -\sin \theta=\sqrt{2}\sin \theta,$$\cos \theta+ \sin \theta=\sqrt{2} \cos \theta$$$\cos \theta -\sin \theta=\sqrt{2}\sin \theta$$\begin{align*} & \cos \theta=\sqrt{2}\sin \theta + \sin \theta \\ \implies & \cos \the… anonymous@undisclosed.example.com (Anonymous) Wed, 27 Nov 2024 16:04:15 +0000 https://www.mathcity.org/math-11-nbf/sol/unit09/re-ex-p3 Question 4, Review Exercise Solutions of Question 4 of Review Exercise of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. anonymous@undisclosed.example.com (Anonymous) Wed, 27 Nov 2024 15:59:20 +0000 https://www.mathcity.org/math-11-nbf/sol/unit09/re-ex-p4 Question 5 and 6, Review Exercise Solutions of Question 5 and 6 of Review Exercise of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. anonymous@undisclosed.example.com (Anonymous) Wed, 27 Nov 2024 15:59:22 +0000 https://www.mathcity.org/math-11-nbf/sol/unit09/re-ex-p5 Question 7, Review Exercise Solutions of Question 7 of Review Exercise of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. anonymous@undisclosed.example.com (Anonymous) Wed, 27 Nov 2024 15:59:22 +0000 https://www.mathcity.org/math-11-nbf/sol/unit09/re-ex-p6 Question 8, Review Exercise Solutions of Question 8 of Review Exercise of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. anonymous@undisclosed.example.com (Anonymous) Wed, 27 Nov 2024 15:59:23 +0000 https://www.mathcity.org/math-11-nbf/sol/unit09/re-ex-p7 Question 9, Review Exercise Solutions of Question 9 of Review Exercise of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. anonymous@undisclosed.example.com (Anonymous) Wed, 27 Nov 2024 15:59:23 +0000 https://www.mathcity.org/math-11-nbf/sol/unit09/re-ex-p8 Question 10(i-v), Review Exercise Solutions of Question 10(i-v) of Review Exercise of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. anonymous@undisclosed.example.com (Anonymous) Wed, 27 Nov 2024 15:59:24 +0000 https://www.mathcity.org/math-11-nbf/sol/unit09/re-ex-p9 Question 10(vi-x), Review Exercise Solutions of Question 10(vi-x) of Review Exercise of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. anonymous@undisclosed.example.com (Anonymous) Wed, 27 Nov 2024 15:59:24 +0000 https://www.mathcity.org/math-11-nbf/sol/unit09/re-ex-p10 Question 10(xi-xv), Review Exercise Solutions of Question 10(xi-xv) of Review Exercise of Unit 09: Trigonometric Functions. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. anonymous@undisclosed.example.com (Anonymous) Wed, 27 Nov 2024 15:59:19 +0000