Standard principal values of inverse tangent for JEE

Formula

\[\tan^{-1}0=0,\ \tan^{-1}\left(\dfrac{1}{\sqrt3}\right)=\dfrac{\pi}{6},\ \tan^{-1}1=\dfrac{\pi}{4},\ \tan^{-1}(\sqrt3)=\dfrac{\pi}{3}\]

Conditions: Using principal values.

Quick evaluation, inverse tangent sum problems.