Question:
Find the value of $2 \sec ^{-1} 2+\sin ^{-1}\left(\frac{1}{2}\right)$
Solution:
$2 \sec ^{-1} 2+\sin ^{-1}\left(\frac{1}{2}\right)=2 \sec ^{-1}\left(\sec \frac{\pi}{3}\right)+\sin ^{-1}\left(\sin \frac{\pi}{6}\right)$
$=2 \times \frac{\pi}{3}+\frac{\pi}{6}$
$=\frac{5 \pi}{6}$