Practicing Success
The value of $cot^{-1}\left[2cos\left(2sin^{-1}\frac{1}{2}\right)\right]$ is |
$\frac{\pi}{6}$ $\frac{\pi}{4}$ $\frac{2\pi}{3}$ $\frac{\pi}{3}$ |
$\frac{\pi}{4}$ |
The correct answer is Option (2) → $\frac{\pi}{4}$ $\cot^{-1}\left[2\cos\left(2\sin^{-1}\frac{1}{2}\right)\right]$ $=\cot^{-1}\left(2\cos\left(2×\frac{π}{6}\right)\right)$ $=\cot^{-1}(2×\frac{1}{2})=\cot^{-1}(1)$ $=\frac{\pi}{4}$ |