## Trigonometry 7th Edition

$cos(\theta)\tan(\theta)=\sin(\theta)$
$\tan(\theta)$ = $\frac{\sin(\theta)}{\cos(\theta)}$ This can be substituted into the equation: $cos(\theta)\tan(\theta)=\cos(\theta)\frac{\sin(\theta)}{\cos(\theta)}=\sin(\theta)$ Therefore, $cos(\theta)\tan(\theta)=\sin(\theta)$