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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 ENGLISH-TRIGONOMETRIC FUNCTIONS-All Questions
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  11. Range of f(theta)=cos^2theta(cos^2theta+1)+2sin^2theta is

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  13. If 0 lt theta lt pi, then minimum value of3sintheta+cosec^3 theta is

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  14. In A B C , let L ,M ,N be the feet of the altitudes. The prove that s...

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