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Thread: Generating inverse

  1. #1
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    Question Generating inverse

    Can someone help me find the inverse of $y = 7 + 5x^3 + x^7$? The fact that there is more than one variable to a unique power makes the inverse a little less obvious than usual.
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  2. #2
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    Re: Generating inverse

    What makes you think there exists a closed formula for this inverse function?
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  3. #3
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    Re: Generating inverse

    Quote Originally Posted by otownsend View Post
    Can someone help me find the inverse of $y = 7 + 5x^3 + x^7$? The fact that there is more than one variable to a unique power makes the inverse a little less obvious than usual.
    Did you look at the PLOT of this function?
    Does it have an inverse?
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  4. #4
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    Re: Generating inverse

    ah...that's a fair point you made. What if you restricted the domain to [-1.21, 1.21], then what would be its inverse ?
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    Re: Generating inverse

    Quote Originally Posted by Plato View Post
    Did you look at the PLOT of this function?
    Does it have an inverse?
    It's entered correctly in the quote box of post # 4, but some
    other expression was entered at the link for the graph.

    - - - - - - - - - - - - - - - - - -

    otownsend, no restrictions have to be made on the domain.
    But as romsek's post questioned about it, it does not
    have a closed form.
    Last edited by greg1313; Jun 20th 2019 at 07:27 AM.
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  6. #6
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    Re: Generating inverse

    Is there more to this problem that you haven't posted, say, finding the value of the derivative of the function's inverse at a specific value?
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