Trigonometry Examples

$- \cos (2 π)$

Step 1

Subtract full rotations of $2 π$ until the angle is greater than or equal to $0$ and less than $2 π$ .

$- \cos (0)$

Step 2

The exact value of $\cos (0)$ is $1$ .

$- 1 \cdot 1$

Step 3

Multiply $- 1$ by $1$ .

$- 1$