arc cosine

(redirected from arc cosines)
Also found in: Dictionary, Thesaurus.

arc cosine

[′ärk ′kō‚sīn]
(mathematics)
Also known as anticosine; inverse cosine.
For a number x, any angle whose cosine equals x.
For a number x, the angle between 0 radians and π radians whose cosine equals x ; it is the value at x of the inverse of the restriction of the cosine function to the interval between 0 and π.