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cos((2pi)/7)+cos((4pi)/7)+cos((6pi)/7)...

`cos((2pi)/7)+cos((4pi)/7)+cos((6pi)/7)`

A

is equal to zero

B

lies between 0 and 3

C

is a negative number

D

lies between 3 and 6

Text Solution

Verified by Experts

The correct Answer is:
C
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