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If x+1/x=2costheta then x^3+1/x^3=...

If `x+1/x=2costheta` then `x^3+1/x^3=`

A

`cos3theta`

B

2cos3theta`

C

`1/2cos3theta`

D

`1/3cos3theta`

Text Solution

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The correct Answer is:
B
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