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Question
If `x + (1)/x = 3`; find `x^2 + (1)/x^2`
Sum
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Solution
`(x + 1/x)^2`
= `x^2 + (1)/x^2 + 2 (x) (1/x)`
⇒ (3)2
= `x^2 + (1)/x^2 + 2`
⇒ `x^2 + (1)/x^2`
= 9 - 2
= 7.
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