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The value of the expression (sin7al...

The value of the expression
`(sin7alpha+6sin 5 alpha+17sin3alpha+12sin alpha)/(sin6alpha+5sin 4alpha+12 sin 2 alpha)`, where `alpha=(pi)/(5)` is equal to :

A

`(sqrt(5)-1)/(4)`

B

` (sqrt(5)+1)/(4)`

C

`(sqrt(5)+1)/(2)`

D

`(sqrt(5)-1)/(2)`

Text Solution

Verified by Experts

The correct Answer is:
C
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VIKAS GUPTA (BLACK BOOK)-COMPOUND ANGLES-Exercise-5 : Subjective Type Problems
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