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cos""(pi)/(15).cos""(2pi)/(15).cos""(4pi...

`cos""(pi)/(15).cos""(2pi)/(15).cos""(4pi)/(15).cos""(8pi)/(15)` is equal to

A

`(1)/(16)`

B

`-(1)/(16)`

C

1

D

0

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The correct Answer is:
B
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LUCENT PUBLICATION-ADVANCED TRIGONOMETRIC IDENTITIES-EXERCISE 13A
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