Geometry & Trigonometry
Advanced

Tangent Half-Angle

Expresses the tangent of a half angle.

Formula

tan⁡θ2=1−cos⁡θsin⁡θ\tan\frac{\theta}{2} = \frac{1-\cos\theta}{\sin\theta}

Variables

\thetaAngle

Example

Used in integration substitutions

Did You Know?

The tangent half-angle substitution can turn any trigonometric integral into an ordinary algebraic one.

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