WorksheetFunction.Asin Method (Excel)
Published: July 16, 2012
Returns the arcsine, or inverse sine, of a number. The arcsine is the angle whose sine is Arg1. The returned angle is given in radians in the range -pi/2 to pi/2.
To express the arcsine in degrees, multiply the result by 180/PI( ) or use the Degrees method.