Given that $\cos \theta = \frac{1}{4}$ and $\sin \theta

Question

Given that $\cos \theta = \frac{1}{4}$ and $\sin \theta < 0$, express $\tan (-\theta)$ in the simplest fractions.

Accepted Answer

$\sqrt{15}$

Trigonometry - Exact Trigonometric Values and the Unit Circle