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JavaScript asin() Method

❮ JavaScript Math Object

Example

Return the arcsine of a number:

Math.asin(0.5);
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Definition and Usage

The asin() method returns the arcsine of a number as a value between -PI/2 and PI/2 radians.

Note: If the parameter x is outside the range -1 to 1, the browser will return NaN.

Tip: 1 will return the value of PI/2. -1 will return the value of -PI/2.


Browser Support

Method
asin() Yes Yes Yes Yes Yes

Syntax

Math.asin(x)

Parameter Values

Parameter Description
x Required. A number

Technical Details

Return Value: A Number, from -PI/2 to PI/2, or NaN if the value is outside the range of -1 to 1
JavaScript Version: ECMAScript 1

❮ JavaScript Math Object