If and are acute angles such that

MATHEMATICS · Subjective · CBSE · Mathematics · Introduction to Trigonometry · Introduction to Trigonometry

Problem

6. If

\angle \mathrm{A}

and

\angle \mathrm{B}

are acute angles such that

\cos \mathrm{A}=\cos \mathrm{B}

, then show that

\angle \mathrm{A}=\angle \mathrm{B}