Answer
$-\frac{1}{2}$, $-1$
Work Step by Step
I know that $\sin$ is an odd function, which means $f(-\theta)=-f(\theta).$ Therefore $\sin{-\frac{\pi}{6}}=-\sin{\frac{\pi}{6}}$.
$\sin{-\frac{\pi}{6}}=-\sin{\frac{\pi}{6}}=-\sin{30^\circ}=-\frac{1}{2}$, $\cos{\pi}=\cos{180^\circ}=-1$
