Answer
0
Work Step by Step
$\tan [n\cdot 180^{\circ}]=\frac{\sin[n\cdot180^{\circ}]}{\cos [n\cdot180^{\circ}]}$
$\sin [n\cdot 180^{\circ}]=0$ and
$\cos[n\cdot180^{\circ}]$ is always non-zero (equal to 1 or -1).
$\implies \tan [n\cdot180^{\circ}]=\frac{0}{\text{non-zero number}}=0$
