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If sin theta+sin2theta+sin3theta=sin alp...

If `sin theta+sin2theta+sin3theta=sin alpha` and `cos theta+cos 2theta+cos3theta=cos alpha`, then `theta` is equal to

A

`(alpha )/(2)`

B

`alpha `

C

`2 alpha`

D

`(alpha )/(6)`

Text Solution

Verified by Experts

The correct Answer is:
C
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