Suppose $$\cos u = \frac{5}{13}$$ and $\sin u$ is negative. Here are some small variations on the previous problems:
$\sin(u) =$
$\sin\left(u-\pi\right) =$
$\cos\left(u-\pi\right) =$
$\sin\left(u-\frac{\pi}{2}\right) =$
$\cos\left(u-\frac{\pi}{2}\right) =$