ASIN function
ASIN returns the inverse trigonometric sine of a number.
Syntax
ASIN (number)
This function returns the inverse trigonometric sine of number, which is the angle (in radians) whose sine is number. The angle returned is between -PI/2 and +PI/2.
Example
=ASIN(0) returns 0.
=ASIN(1) returns 1.5707963267949 (PI/2 radians)..
=DEGREES(ASIN(0.5)) returns 30. The sine of 30 degrees is 0.5.