ASIN

float asin(float argument)

Returns the arcsine of the argument. The argument must be in the range [-1, 1].

The arcsine is the angle such that sin(angle) = argument. It's expressed in radians. Range: [-PI / 2, PI / 2].

To convert the result to degrees, multiply by 180 / PI or use the degrees conversion function.

Example

=asin(-0.5)

returns 0.523598775598299 = PI / 6 radians. You can verify that

=sin(PI / 6)

is -0.5. To express the arccosine in degrees, you can use

=degrees(asin(-0.5))

to get the answer -30 degrees.