mathjs/docs/reference/functions/acos.md

Function acos

Calculate the inverse cosine of a value.

For matrices, the function is evaluated element wise.

Syntax

math.acos(x)

Parameters

Parameter	Type	Description
x	Number | BigNumber Boolean | Complex | Array | Matrix | null	Function input

Returns

Type	Description
Number | BigNumber | Complex | Array | Matrix	The arc cosine of x

Examples

math.acos(0.5);           // returns Number 1.0471975511965979
math.acos(math.cos(1.5)); // returns Number 1.5

math.acos(2);             // returns Complex 0 + 1.3169578969248166 i

See also

cos, atan, asin