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If x+1/x=7, find the value of x^3+1/(x^3...

If `x+1/x=7,` find the value of `x^3+1/(x^3)`

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Given:
`x+1/x=7`
=`(x+1/x)^3=7^3`
=`x^3+1/(x^3)+3(x)(1/x)(x+1/x)=343`
[`(a+b)^3=a^3+b^3+3ab(a+b)`]
=`x^3+1/(x^3)+3(7)=343`
=`x^3+1/(x^3)=343−21`
=`x^3+1/(x^3)=322`
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