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Question
If `x^2 + (1)/x^2 = 18`; find : `x - (1)/x`
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Solution
`x^2 + (1)/x^2 = 18`
Using `(x - 1/x)^2`
= `x^2 + (1)/x^2 - 2`
⇒ `(x - 1/x)^2`
= 18 - 2
= 16
⇒ `x - (1)/x`
= 4.
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