Chapter 3
Comprehensive Trigonometry for IIT JEE Main and Advanced Rejaul Makshud MeGraw Hill · 116 exercises
Problem 52
Solve the following equations and tick the correct one. The number of solutions of the cquation \(2\left(\sin ^{4} 2 x+\cos ^{4} 2 x\right)+3 \sin 2 x \cos 2 x=0\) is (a) 0 (b) 1 (c) 2 (d) 3
4 step solution
Problem 53
Solve the following equations and tick the correct one. \(\cos 2 x+a \sin x=2 a-7\) possesses a solution for (a) all \(a\) (b) \(a>6\) (c) \(a \leq 2\) (d) \(a \in[2,6]\)
5 step solution
Problem 54
Solve the following equations and tick the correct one.
If \(0
3 step solution
Problem 55
Solve the following equations and tick the correct one. If \(1+\sin \theta+\sin ^{2} \theta+\ldots \ldots\) to \(\infty=4+2 \sqrt{3}\), \(0<\theta<\pi, \theta \neq \frac{\pi}{2}\), then (a) \(\theta=\frac{\pi}{6}\) (b) \(\theta=\frac{\pi}{3}\) (c) \(\theta=\frac{\pi}{3}\) or \(\frac{\pi}{6}\) (d) \(\frac{\pi}{3}\) or \(\frac{2 \pi}{3}\)
3 step solution
Problem 56
Solve the following equations and tick the correct one. If \(\tan (\pi \cos \theta)=\cot (\pi \sin \theta)\), then the value of \(\cos \left(\theta-\frac{\pi}{4}\right)\) is (a) \(\frac{1}{2}\) (b) \(\frac{1}{\sqrt{2}}\) (c) \(\frac{1}{2 \sqrt{2}}\) (d) None
4 step solution
Problem 57
Solve the following equations and tick the correct one. The most general values of \(x\) for which \(\sin x+\cos x=\min _{a \in R}\left\\{1, a^{2}-4 a+6\right\\}\) are given by (a) \(2 n \pi, n \in N\) (b) \(2 n \pi+\frac{\pi}{2}, n \in N\) (c) \(n \pi+(-1)^{n} \frac{\pi}{4}-\frac{\pi}{4}, n \in N\) (d) None
4 step solution
Problem 59
Solve the following equations and tick the correct one. The number of roots of the equation \(x+2 \tan x=\frac{\pi}{2}\) in the interval \([0,2 \pi]\) is (a) 1 (b) 2 (c) 3 (d) \(\infty\)
4 step solution
Problem 60
Solve the following equations and tick the correct one. The number of solutions of the equation \(\cos (\pi \sqrt{x-4})\) \(\cos (\pi \sqrt{x})=1\) is (a) None (b) 1 (c) 2 (d) \(>2\)
3 step solution
Problem 61
Solve the following equations and tick the correct one. The number of solutions of the equation \(\sin \left(\frac{\pi x}{2 \sqrt{3}}\right)=x^{2}-2 \sqrt{3} x+4\) (a) forms an empty set (b) only one (c) is only two (d) is greater then two
4 step solution
Problem 62
Solve the following equations and tick the correct one. Number of real roots of the equation \(\sec \theta+\operatorname{cosec} \theta=\sqrt{15}\) lying between 0 and \(2 \pi\) is (a) \(\underline{8}\) (b) 4 (c) 2 (d) 0
3 step solution
Problem 63
Solve the following equations and tick the correct one. The general solution of the equation \(\sin 100 x-\cos 100 x=1\), is (a) \(2 n \pi+\frac{\pi}{3}, n \in z\) (b) \(n \pi+\frac{\pi}{2}, n \in z\) (c) \(n \pi+\frac{\pi}{4} \pi, n \in z\) (d) \(2 n \pi \frac{\pi}{3}, n \in z\)
4 step solution
Problem 65
Solve the following equations and tick the correct one. The general solution of the equation \(2^{\cos ^{2} x}+1=3.2^{-\sin ^{2} x}\) is (a) \(n \pi \cdot n \in z\) (b) \((n+1) \pi, n \in z\) (c) \((n-1) \pi, n \in z\) (d) None
3 step solution
Problem 66
Solve the following equations and tick the correct one. If \(x \in(0,1)\), the greatest root of the equation \(\sin 2 \pi x=\sqrt{2} \cos \pi x\) is (a) \(\frac{1}{4}\) (b) \(\frac{1}{2}\) (c) \(\frac{3}{4}\) (d) None
4 step solution
Problem 67
Solve the following equations and tick the correct one. The number of solutions of tan \((5 \pi \cos \alpha)\) \(=\cot (5 \pi \sin \alpha)\) for \(\alpha \in(0,2 \pi)\) is (a) 7 (b) 14 (c) 21 (d) 3
3 step solution
Problem 68
Solve the following equations and tick the correct one. The number of solution of the equation \(1+\sin x \cdot \sin ^{2}\left(\frac{x}{2}\right)=0\) in \([-\pi, \pi]\) is (a) 0 (b) \(\underline{1}\) (c) 2 (d) 3
4 step solution
Problem 70
Solve the following equations and tick the correct one. The real roots of the equation \(\cos ^{7} x+\sin ^{4} x=1\) in \((-\pi, \pi)\) are (a) \(-\frac{\pi}{2}, 0\) (b) \(-\frac{\pi}{2}, 0, \frac{\pi}{2}\) (c) \(\frac{\pi}{2}, 0\) (d) \(0, \frac{\pi}{4}, \frac{\pi}{2}\)
6 step solution