Answer
a. $\sin A$.
b. $\cos A$.
c. $\tan A$.
Work Step by Step
a.
$=\cos A\cdot \tan A$
Use $\tan A=\frac{\sin A}{\cos A}$.
$=\cos A\cdot \frac{\sin A}{\cos A}$
Cancel common terms.
$=\sin A$.
b.
$=\sin A\div \tan A$
Use $\tan A=\frac{\sin A}{\cos A}$.
$=\sin A\div \frac{\sin A}{\cos A}$
$=\sin A\times \frac{\cos A}{\sin A}$
Cancel common terms.
$=\cos A$.
c.
$=\sin A\div \cos A$
Write as a fraction.
$=\frac{\sin A}{ \cos A}$
Use $\frac{\sin A}{\cos A}=\tan A$.
$=\tan A$.
