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Show that (1+ cos. (pi)/(8))(1+cos. (3pi...

Show that `(1+ cos. (pi)/(8))(1+cos. (3pi)/(8))(1+ cos. (5pi)/(8))(1+ cos .(7pi)/(8))=(1)/(8)`

A

`(1+ sqrt2)/(2 sqrt2)`

B

`pi/8`

C

`1/8`

D

`1/2`

Text Solution

Verified by Experts

The correct Answer is:
C
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