Arccosine
Definition of Arccosine
- Arccosine is the inverse function of cosine. It is also written as arccos or

If y = cos x, then x = arccos y.
Examples of Arccosine

or
This means that the angle 30° has cosine equal to
.
Solved Example on Arccosine
Choices:
A. 0.3
B. 0.2
C. 0.5
D. 0.6
Correct Answer: D
Solution:
Step 1: Recall that cos(arccos x) = x, for
.

Related Terms for Arccosine
Additional Links for Arccosine