Practicing Success

Target Exam

CUET

Subject

-- Mathematics - Section B1

Chapter

Inverse Trigonometric Functions

Question:

The value of $cot^{-1}\left[2cos\left(2sin^{-1}\frac{1}{2}\right)\right]$ is

Options:

$\frac{\pi}{6}$

$\frac{\pi}{4}$

$\frac{2\pi}{3}$

$\frac{\pi}{3}$

Correct Answer:

$\frac{\pi}{4}$

Explanation:

The correct answer is Option (2) → $\frac{\pi}{4}$

$\cot^{-1}\left[2\cos\left(2\sin^{-1}\frac{1}{2}\right)\right]$

$=\cot^{-1}\left(2\cos\left(2×\frac{π}{6}\right)\right)$

$=\cot^{-1}(2×\frac{1}{2})=\cot^{-1}(1)$

$=\frac{\pi}{4}$