Reference > Functions reference > Trigonometric functions > Asin


Returns the arcsine (Asin), or inverse sine, of a number.


Asin (number)


number - any numeric expression or field containing a numeric expression in the range -1 to 1

Data type returned 


Originated in 

FileMaker Pro 9.0


The arcsine is the angle whose sine is number. The returned angle is given in radians in the range -Pi/2 to Pi/2. The input number parameter must be between -1 and 1.

To express the arcsine in degrees, multiply the result by 180/Pi or use the Degrees function.

Example 1 

Asin(-0.5) returns -0.523598776.

Asin(-0.5)*180/Pi returns -30.

Degrees(Asin(-0.5)) returns -30.

Asin(2)returns ? (not a number).

Related topics 

Functions reference (category list)

Functions reference (alphabetical list)

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