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If x is root of (1+x^(4))=7(1+x)^(4) the...

If `x` is root of `(1+x^(4))=7(1+x)^(4)` then `|x+1/x|=` ?

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The correct Answer is:
3
`:' x^(2)(x^(2)+1/(x^(2)))=7(x^(2)+2x+)^(2)`
`x^(2)+1/(x^(2))=7(x+2+1/x)^(2)`
Let `alpha+1/(alpha)=t`
`impliest^(2)-2=7(t+2)^(2)`
`impliest=3` or `-5/3`
`implies|t|=3` or `5/3`
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