Question

Evaluate
${\cos }^{-1}\frac{1}{2}+2{\sin }^{-1}\frac{1}{2}$

Answer 1

$\begin{array}{c}{\cos }^{-1}\frac{1}{2}=\frac{\pi }{3}\\ {\sin }^{-1}\frac{1}{2}=\frac{\pi }{6}\\ {\cos }^{-1}\frac{1}{2}+2{\sin }^{-1}\frac{1}{2}\\ \frac{\pi }{3}+\frac{2\pi }{6}\\ =\frac{2\pi }{3}\end{array}$