ASIN(x)
ASIN function calculates the arc sine of @x; that is the value whose sine is @x. If @x falls outside the range -1 to 1, ASIN fails and returns the NUM! error. This function is Excel compatible.
ASIN(0.5) equals 0.523599.
ASIN(1) equals 1.570797.
SIN , COS , ASINH , DEGREES , RADIANS