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Ifcos5theta=acos^5theta+bcos^3theta+ccos...

If`cos5theta=acos^5theta+bcos^3theta+ccostheta` then c is equal to

A

(-5)

B

1

C

5

D

none of these

Text Solution

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The correct Answer is:
C
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PATHFINDER-TRIGONOMETRIC RATIOS AND IDENTITIES-QUESTION BANK
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  13. Let n be a fixed positive integer such that sin(pi/(2n))+cos(pi/(2n))=...

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