Trigonometry Examples

$\sin (- x) = - \sin (x)$

Step 1

Start on the left side.

$\sin (- x)$

Step 2

Since $\sin (- x)$ is an odd function, rewrite $\sin (- x)$ as $- \sin (x)$ .

$- \sin (x)$

Step 3

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

$\sin (- x) = - \sin (x)$ is an identity