Answer
$\tan(x-\pi)=\tan(x)$
Work Step by Step
$\tan(x-\pi)$
Expand using subtraction formula for tangent on page 545:
$=\frac{\tan(x)-\tan(\pi)}{1+\tan(x)\tan(\pi)}$
Evaluate $\tan(\pi)$:
$=\frac{\tan(x)-0}{1+\tan(x)*0}$
Simplify:
$=\frac{\tan(x)}{1}$
$=\tan(x)$
Therefore, $\tan(x-\pi)=\tan(x)$.
