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If cos^(3) theta + cos^(3)((2pi)/(3) + t...

If `cos^(3) theta + cos^(3)((2pi)/(3) + theta) + cos^(3)((4pi)/(3) + theta) = a cos 3 theta`, then a =

A

`1/4`

B

`3/4`

C

`5/4`

D

`7/4`

Text Solution

Verified by Experts

The correct Answer is:
B
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