The ATAN function returns the arctangent, or inverse tangent, of a number. The returned angle is given in radians in the range -pi/2 to pi/2.
Formula:
=ATAN(number)
Explanations:
Number is required, the tangent of the angle you want.
Cautions:
– The result is the angle in radians, use 180/PI() or use the DEGREES function to convert into degrees.