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If x=(5-sqrt(21))/2 then prove that (x^3...

If `x=(5-sqrt(21))/2` then prove that `(x^3+1/x^3)-5(x^2+1/x^2)+(x+1/x)=0`

A

0

B

1

C

2

D

-1

Text Solution

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The correct Answer is:
A
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