2

Given that $f(x) = x + \frac{1}{x}$ where $x>1$, find $f^{-1}(x)$.

I don't understand and how to start. Please help.

Ivo Terek
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noobie
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  • The function $f$ is not injective on its maximum domain. There are restrictions in which it is injective. To find them multiply $f(x)=x+\frac 1 x$ by $x$ and use the quadratic formula to solve for $x$. – Git Gud Aug 03 '14 at 00:40
  • Annoyance: downvotes on questions that get mooted by edits. If an edit moots a post, then point that out and the poster can delete it. – ncmathsadist Aug 03 '14 at 12:56

1 Answers1

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Set $y = x + 1/x$ and solve for $x$.

Paul Sundheim
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