Trigonometry Examples

$\cos (- 990)$

Step 1

Add full rotations of $360$ ° until the angle is between $0$ ° and $360$ °.

$\cos (90)$

Step 2

The exact value of $\cos (90)$ is $0$ .

$0$

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