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Question
If `x^2 + (1)/x^2 = 18`; find : `x^3 - (1)/x^3`
Sum
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Solution
`(x^3 - (1)/x)^3`
= `x^3 - (1)/x^3 - 3(x - 1/x)`
⇒ 64 = `x^3 - (1)/x^3 - 3(4)`
⇒ `x^3 - (1)/x^3`
= 64 + 12
= 76.
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