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In triangle ABC , prove that tan (B-C)/2...

In triangle ABC , prove that `tan (B-C)/2 =[( b-c) /(b+c )] cot A/2` , ` tan (C-A)/2 = [(c-a)/(c+a)]cot B/2 `,` tan (A-B)/2 = [(a-b)/(a+b)]cot c/2`

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To prove the identities given in the question, we will follow a systematic approach. Let's start with the first identity. ### Step 1: Prove \( \tan \frac{B-C}{2} = \frac{b-c}{b+c} \cot \frac{A}{2} \) 1. **Using the Sine Rule**: According to the sine rule, we have: \[ \frac{a}{\sin A} = \frac{b}{\sin B} = \frac{c}{\sin C} = k \] ...
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