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Question
Answer the following questions in one word or one sentence or as per exact requirement of the question.
If in a ∆ABC, \[\frac{\cos A}{a} = \frac{\cos B}{b} = \frac{\cos C}{c}\] then find the measures of angles A, B, C.
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Solution
In ∆ABC,
\[ \Rightarrow \frac{\cos A}{k\sin A} = \frac{\cos B}{k\sin B} = \frac{\cos C}{k\sin C} \left( \text{ Using sine rule } \right)\]
\[ \Rightarrow \cot A = \cot B = \cot C\]
\[ \Rightarrow A = B = C\]
∴ A = B = C = 60º
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