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The value of co s pi/5 co s.2pi / 5 c o ...

The value of `co s pi/5 co s.2pi / 5 c o s 4pi / 5 co s 8pi / 5 = `

A

`(1)/(16)`

B

0

C

`(-1)/(8)`

D

`(-1)/(16)`

Text Solution

Verified by Experts

The correct Answer is:
D
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TARGET PUBLICATION-TRIGONOMETRIC FUNCTIONS OF COMPOUND ANGLES -CRITICAL THINKING
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