The Math.asin()
function returns the arcsine (in radians) of a number, that is
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Syntax
Math.asin(x)
Parameters
- x
- A number.
Return value
The arcsine (in radians) of the given number if it's between -1 and 1; otherwise, NaN
.
Description
The Math.asin()
method returns a numeric value between and radians for x between -1 and 1. If the value of x is outside this range, it returns NaN
.
Because asin()
is a static method of Math
, you always use it as Math.asin()
, rather than as a method of a Math
object you created (Math
is not a constructor).
Examples
Using Math.asin()
Math.asin(-2); // NaN Math.asin(-1); // -1.5707963267948966 (-pi/2) Math.asin(0); // 0 Math.asin(0.5); // 0.5235987755982989 Math.asin(1); // 1.5707963267948966 (pi/2) Math.asin(2); // NaN
For values less than -1 or greater than 1, Math.asin()
returns NaN
.
Specifications
Specification |
---|
ECMAScript (ECMA-262) The definition of 'Math.asin' in that specification. |
Browser compatibility
Desktop | Mobile | Server | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
asin | Chrome Full support 1 | Edge Full support 12 | Firefox Full support 1 | IE Full support 3 | Opera Full support 3 | Safari Full support 1 | WebView Android Full support 1 | Chrome Android Full support 18 | Firefox Android Full support 4 | Opera Android Full support 10.1 | Safari iOS Full support 1 | Samsung Internet Android Full support 1.0 | nodejs Full support 0.1.100 |
Legend
- Full support
- Full support