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One-to-one functions and inverse functions.

  1. May 22, 2013 #1
    I was just wondering if inverse functions only apply to one-to-one functions?(Or a function who's domain has been restricted to act as a one-to-one function). Thanks.
  2. jcsd
  3. May 22, 2013 #2


    Staff: Mentor

    Yes, the function has to be one-to-one in order to have an inverse. For example, f(x) = x2 is not one-to-one, so doesn't have an inverse. However, if you restrict the domain to, say, x ≥ 0, then this restricted-domain function does have an inverse.

    Alternatively, you could restrict the domain to x ≤ 0, and that function would have an inverse.
  4. May 22, 2013 #3
    Thanks for that!
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