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प्रश्न
if `x + 1/x = 11`, find the value of `x^2 + 1/x^2`
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उत्तर
We have `x + 1/x = 11`
Now `(x + 1/x)^2= x^2 + (1/x)^2 + 2 xx x xx 1/x`
`=> (x + 1/x)^2 = x^2 + 1/x^2 + 2`
`=> (11)^2 = x^2 + 1/x^2 + 2` [∵ `x = 1/x = 11`]
`=> 121 = x^2 = 1/x^2 + 2 `
`=> x^2 + 1/x^2 = 119`
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