Get Arcsine Method
The Get Arcsine method returns an approximate arcsine of the value that the number argument contains expressed in radians in the range of negative pi/2 through pi/2. If any of the following situations are true, then this method returns NaN:
It cannot convert the value to a number.
The value is greater than 1 or less than negative 1.
This method uses the same argument as the Get Absolute Value method. For more information, see Get Absolute Value Method.
Format
Math.asin(number)