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Math Help - inverse function

  1. #1
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    Unhappy inverse function

    how do i find the inverse function of : y = x + \frac{1}{x}

    this one is giving me trouble.
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  2. #2
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    Quote Originally Posted by tsal15 View Post
    how do i find the inverse function of : y = x + \frac{1}{x}

    this one is giving me trouble.
    So you want to get x with respect to y.

    xy=x^2+1

    x^2-xy+1=0

    solve the quadratic
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  3. #3
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    Quote Originally Posted by Moo View Post
    So you want to get x with respect to y.

    xy=x^2+1

    x^2-xy+1=0

    solve the quadratic
    So, using the quadratic equation, i got  y = \frac{x \pm \sqrt{x^2 -4}}{2} as the inverse function. Correct?
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  4. #4
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    switch x and y

    yes you are correct
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