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If cos 5 theta = a cos^(5)theta + b cos^...

If `cos 5 theta = a cos^(5)theta + b cos^(3)theta+c cos theta`. Then, find the value of c.

A

`a=20`

B

`b=-20`

C

`c=16`

D

`c=5`

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The correct Answer is:
B, C
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