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In triangle ABC, s= (a+b+c)/2, then (b c...

In `triangle ABC`, `s= (a+b+c)/2`, then `(b cos^2 frac (C)(2)+ c cos^2 frac (B)(2))` equals:

A

s

B

2s

C

3s

D

4s.

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In any triangle ABC, prove that : (b-c)/a= (sin frac (B-C)(2))/(cos frac (A)(2)) .

In any triangle ABC, prove that : sin frac (B-C)(2) = (b-c)/(a) cos frac (A)(2) .

In any triangle ABC, prove that : sin frac (A-B)(2)= (a-b)/c cos frac (C)(2) .

In any triangle ABC, prove that : (a-b)/c= (sin frac (A-B)(2))/(cos frac (C)(2)) .

In any triangle ABC, prove that : cos frac (B-C)(2)= 2 sin frac (A)(2) , when b+c=2a .

In any triangle ABC, prove that : a cos frac (B-C)(2)= (b +c) sin frac (A)(2)= (b+c)cos frac (B+C)(2) .

For any triangle ABC, prove that : (a+b)/c= (cos frac (A-B)(2))/(sin frac (C)(2)) .

In any triangle ABC, prove that : a (cos B + cos C) = 2 (b +c) sin^2 frac (A)(2) .

In any triangle ABC, prove that : cos frac (A)(2) +cos frac (B)(2)+cos frac (C)(2)= 4 cos frac (pi-A)(4) cos frac (pi-B)(4) cos frac (pi-C)(4) .

In any triangle ABC, prove that : a (cos C - cos B) = 2 (b-c) cos^2 frac (A)(2) .

MODERN PUBLICATION-TRIGNOMETRY-EXERCISE
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