I need help with this question:
Find the exact value of tan(v+3pi)
tan v = -3 in the interval (pi/2, pi)
edit: removed first part since you no longer ask for it (mine was dodgy anyway), and fixed typos.
Hint: Tan is a periodic function (its value repeats every $\displaystyle \pi$).
if you need a bit more, try calculating
$\displaystyle tan(1)$
$\displaystyle tan(1 + \pi)$
$\displaystyle tan(1 + 2\pi)$
...