Trigonometry Examples

$\cos (x) = \sin (x) \cot (x)$

Step 1

Start on the right side.

$\sin (x) \cot (x)$

Step 2

Write $\cot (x)$ in sines and cosines using the quotient identity.

$\sin (x) \frac{\cos (x)}{\sin (x)}$

Step 3

Cancel the common factor of $\sin (x)$ .

$\cos (x)$

Step 4

Because the two sides have been shown to be equivalent, the equation is an identity.

$\cos (x) = \sin (x) \cot (x)$ is an identity