Precalculus Examples

$\sin (- 30 °)$

Find the value using the definition of sine.

$\sin (- 30 °) = \frac{opposite}{hypotenuse}$

Substitute the values into the definition.

$\sin (- 30 °) = \frac{- \frac{1}{2}}{1}$

Divide $- \frac{1}{2}$ by $1$ .

$- \frac{1}{2}$

$[\begin{array}{c} x^{2} & \frac{1}{2} \\ \sqrt{π} & \int x d x \end{array}]$