A Cotangent Symmetry

★ 8/10trigonometry Substitution Trigonometric Identities Triangle Geometry

Problem

The angles of $\triangle ABC$ satisfy

\sin A\cot B + \sin B\cot A = 2\sin\frac{C}{2}.

Prove that $A = B$ .

Answer

Solution

Difficulty	8/10
Topics	trigonometry, Substitution, Trigonometric Identities, Triangle Geometry

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