# Arccosine

## Definition Of Arccosine

Arccosine is the inverse function of cosine. It is also written as arccos or cos-1.
If y = cos x, then x = arccos y.

### Examples of Arccosine

or
This means that the angle 300 has cosine equal to .

A. 0.3
B. 0.2
C. 0.5
D. 0.6