The value of cos ""pi/7 cos ""(2pi)/(7) ...

The value of `cos ""pi/7 cos ""(2pi)/(7) cos ""(3pi)/(7)` is-

A

`-1`

B

1

C

`-1/8`

D

`1/8`

Text Solution

Verified by Experts

The correct Answer is:

D

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Knowledge Check

The value of (cos ^(2) ""(pi)/(12)+ cos^(2) ""(pi)/(4)+ cos ^(2) ""(5pi)/(12)) is-

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The value of sin ""pi/14 sin ""(3pi)/(14)sin ""(5pi)/14 sin ""(7pi)/(14) is-

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`1/8`

B

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`1/2`

D

1

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