# What is the exact value of cos -330?

Jul 5, 2015

Find cos (-330)

#### Explanation:

On the trig unit circle:

cos (-330) = cos (30 - 360) = cos 30

Trig table gives -> $\cos 30 = \frac{\sqrt{3}}{2}$

$\cos \left(- 330\right) = \frac{\sqrt{3}}{2}$