Prove the following results relating to the tangent of a double angle.

MATHEMATICS · Multi-part · CBSE · Mathematics · Trigonometric Functions · Trigonometric Functions

Problem

Prove the following results relating to the tangent of a double angle. (i) Starting with sin⁡2θ\sin 2\theta and cos⁡2θ\cos 2\theta, obtain an expression for tan⁡2θ\tan 2\theta in terms of tan⁡θ\tan\theta. (ii) Using the result of part (i), verify that tan⁡2θ (1−tan⁡2θ)=2tan⁡θ\tan 2\theta\,(1-\tan^{2}\theta)=2\tan\theta whenever the functions are defined.

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