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Statement-1 : cos.(pi)/(7)cos.(2pi)/(7)c...

Statement-1 : `cos.(pi)/(7)cos.(2pi)/(7)cos.(4pi)/(7)=-(1)/(8)`
Statement-2 : `costhetacos2thetacos2^(2)thetaunderset(cos2^(n-1)theta)(............)=-(1)/(2^(n))" if "theta=(pi)/(2^(n)-1)`

A

Statement-1 is true, statement-2 is true, statement-2 is a correct explanation for statement-1

B

Statement-1 is true, statement-2 is true, statement-2 is not a correct explanation for statement-1

C

Statement-1 is true, statement-2 is false

D

Statement-1 is false, statement-2 is true

Text Solution

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The correct Answer is:
A
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