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The Math.cos()
function returns the cosine of a number.
Syntax
Math.cos(x)
Parameters
x
- A number given in unit of radians.
Return value
The cosine of the given number.
Description
The Math.cos()
method returns a numeric value between -1 and 1, which represents the cosine of the angle.
Because cos()
is a static method of Math
, you always use it as Math.cos()
, rather than as a method of a Math
object you created (Math
is not a constructor).
Examples
Using Math.cos()
Math.cos(0); // 1 Math.cos(1); // 0.5403023058681398 Math.cos(Math.PI); // -1 Math.cos(2 * Math.PI); // 1
Specifications
Specification | Status | Comment |
---|---|---|
ECMAScript 1st Edition (ECMA-262) | Standard | Initial definition. Implemented in JavaScript 1.0. |
ECMAScript 5.1 (ECMA-262) The definition of 'Math.cos' in that specification. |
Standard | |
ECMAScript 2015 (6th Edition, ECMA-262) The definition of 'Math.cos' in that specification. |
Standard | |
ECMAScript 2017 Draft (ECMA-262) The definition of 'Math.cos' in that specification. |
Draft |
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
---|---|---|---|---|---|
Basic support | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) |
Feature | Android | Chrome for Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|
Basic support | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) |