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In A B C , the three bisectors of the a...

In ` A B C ,` the three bisectors of the angle A, B and C are extended to intersect the circumcircle at D,E and F respectively. Prove that `A DcosA/2+B EcosB/2+C FcosC/2=2R(sinA+sinB+sinC)`

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CENGAGE PUBLICATION-TRIGONOMETRIC FUNCTIONS-All Questions
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