Trigonometry Examples

$- \frac{π}{2}$

Step 1

Take the cosine of $- \frac{π}{2}$ .

$\cos (- \frac{π}{2})$

Step 2

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

$\cos (\frac{3 π}{2})$

Step 3

Apply the reference angle by finding the angle with equivalent trig values in the first quadrant.

$\cos (\frac{π}{2})$

Step 4

The exact value of $\cos (\frac{π}{2})$ is $0$ .

$0$