Question:
Find the principal value of each of the following :
$\cos ^{-1} \frac{1}{2}+2 \sin ^{-1} \frac{1}{2}$
Solution:
Putting the values of the inverse trigonometric terms
$\frac{\pi}{3}+2 \times \frac{\pi}{6}$
$=\frac{\pi}{3}+\frac{\pi}{3}$
$=\frac{2 \pi}{3}$