Returns the arcsine, or inverse sine, of a number. The arcsine is the angle whose sine is number. The returned angle is given in radians in the range pi/2 to pi/2.
Syntax
ASIN(number)
Number is the sine of the angle you want and must be from 1 to 1.
Remark
To express the arcsine in degrees, multiply the result by 180/PI( ) or use the DEGREES function.
Example
The example may be easier to understand if you copy it to a blank worksheet.
How to copy an example
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Selecting an example from Help
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A 
B 
Formula 
Description (Result) 
=ASIN(0.5) 
Arcsine of 0.5 in radians, pi/6 (0.5236) 
=ASIN(0.5)*180/PI() 
Arcsine of 0.5 in degrees (30) 
=DEGREES(ASIN(0.5)) 
Arcsine of 0.5 in degrees (30) 
