Answer
$-\frac{\pi}{3}$
Work Step by Step
Let $\tan^{-1}(-\sqrt {3})=y$
Then,
$\tan y= -\sqrt {3}= -\tan\frac{\pi}{3}=\tan(-\frac{\pi}{3})$.
This implies $y= -\frac{\pi}{3}$
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.