Arctangent is the inverse of tangent, and itÂ refers to finding the angle whose tangent is given byÂ a number or ratio. For example, the arctangent of 1 is equal to an angle that measures 45 degrees. This is the inverse of finding the tangent of 45 degrees, which equals 1.
In trigonometry, tangent (tan) and arctangent (arctan) are functions associated with a right triangle. The tangent of an angle can be found by using the formula opposite side (O) of angle C divided by the adjacent side (A), or the ratio O/A. Therefore, tan(C) = O/A and angle C = arc tan (O/A).
An example of finding the arctan is the problem tan(C) = 3/4 or 0.75. Angle A equals the arctan(.75), and angle C equals 36.87 degrees. For inverse functions, the range is between -90 degrees and +90 degrees, while the domain is all real numbers.