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cos^4(pi/8)+cos^4((3pi)/8)+cos^4((5pi)/8...

`cos^4(pi/8)+cos^4((3pi)/8)+cos^4((5pi)/8)+cos^4((7pi)/8)=`

A

`0`

B

`1//2`

C

`3//2`

D

`1`

Text Solution

Verified by Experts

The correct Answer is:
C
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