Find the exact values of sin(120°) and cos(120°).

The angle 120° lies in Quadrant II.

First, find its reference angle:
180° - 120° = 60°

So the reference angle is 60°.

The standard values for 60° are:
sin(60°) = √3/2
cos(60°) = 1/2

In Quadrant II, sine is positive and cosine is negative.

Therefore:
sin(120°) = √3/2
cos(120°) = -1/2

These are the exact values.