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In any triangle A B C , prove that follo...

In any triangle `A B C` , prove that following : `(a-b)cos(C/2) = csin((A-B)/2)`

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Verified by Experts

On using the sine rule as we know,

`=frac{a}{sin A}=frac{b}{sin B}=frac{c}{sin C}=k`

`=frac{a}{sin A}=k`

So, `a={k} sin {A}`

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RD SHARMA-SINE AND COSINE FORMULAE AND THEIR APPLICATIONS-Solved Examples And Exercises
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