Trigonometry
Advanced

Tangent of a Sum

Angle addition formula for tangent.

Formula

tan⁡(A+B)=tan⁡A+tan⁡B1−tan⁡Atan⁡B\tan(A+B) = \frac{\tan A + \tan B}{1 - \tan A\tan B}

Variables

A,BAngles

Did You Know?

The tangent addition formula is the trick behind combining two slopes into the angle between two lines.

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