ACOT function
ACOT returns the inverse cotangent of a number. The angle is measured in radians.
Syntax
ACOT(number)
number is the cotangent of the angle that you want. It must be a real number.
Note: The angle returned is between 0 and pi. To return the angle in degrees, use the DEGREES
function.
=ACOT(1) returns 0.785398163.