cos(pi/7)cos((2pi)/7)cos((4pi)/7)=.........

`cos(pi/7)cos((2pi)/7)cos((4pi)/7)=`................ A) 0 B) `1/2` C) `1/4` D) `-1/8`

A

0

B

`1/2`

C

`1/4`

D

`-1/8`

Verified by Experts

The correct Answer is:

D

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