Question

How do you find the exact value for $\tan \left(120°\right)?$

Answer 1

Solve for the value of $\tan \left(120°\right)$:

Given: $\tan \left(120°\right)$

$\tan \left(120°\right)=\tan (180°-60°)$

using identity $\tan (180°-A)=-\tan \left(A\right)$

$$\begin{gathered} \tan (180°-60°)=-\tan \left(60°\right) \\ \tan (120°)=-\sqrt{3} \end{gathered}$$

Hence, $\tan \left(120°\right)=-\sqrt{3}$ .