Make Math Work
ArcCosine
Usage:ArcTan Tangent
 ATan Tangent
 ArcTangent Tangent

The ArcTan command returns the angle in radians of the entered Tangent. This is the inverse function of Tangent.

Examples:
ArcTan .707 returns 0.615408517629256.
ArcTan (tan(.707)) returns .707.


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