# How do you evaluate cos^-1(1/2)?

${\cos}^{- 1} \left(\frac{1}{2}\right) = \frac{\pi}{3}$
As $\cos \left(\frac{\pi}{3}\right) = \frac{1}{2}$,
${\cos}^{- 1} \left(\frac{1}{2}\right) = \frac{\pi}{3}$