Returns the inverse tangent (the arctangent) of a number.
- returns the inverse trigonometric tangent of number, in other words the angle (in radians) whose tangent is number. The angle returned is between -PI/2 and PI/2.
- To return the angle in degrees, use the DEGREES function.
- returns 0.785398163397448 (PI/4 radians).
- returns 45. The tangent of 45 degrees is 1.