JavaScript Math.acos()

let x = Math.acos(-1);

let x = Math.acos(0);

let x = Math.acos(1);

Description

The Math.acos() method returns the arccosine (in radians) of a number.

The Math.acos() method returns a value value between 0 and PI.

The Math.acos() method expects a parameter in the range -1 to 1.

Math.acos(-1) returns PI.

Math.acos(0) returns PI/2.

Math.acos(1) returns 0.

Math.acos( x)

Parameter	Description
x	Required. A number.

Type	Description
Number	0 to PI. `NaN` if the parameter is outside the range of -1 to 1 or not numeric.

Math.acos() is an ECMAScript1 (ES1) feature.

ES1 (JavaScript 1997) is fully supported in all browsers:


Chrome	Edge	Firefox	Safari	Opera	IE
Yes	Yes	Yes	Yes	Yes	Yes