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Math Help - xsinx inverse

  1. #1
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    Red face xsinx inverse

    hi..
    I have a question about how to get the inverse of f(x)=xsinx
    This is for my extra credit on AP Calc class
    Thank you very much
    Last edited by Kyaoo; September 25th 2009 at 08:28 AM.
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  2. #2
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    Quote Originally Posted by Kyaoo View Post
    hi..
    I have a question about how to get the inverse of xsinx
    This is for my extra credit on AP Calc class
    Thank you very much
    If y = x\sin{x}, then the inverse function is

    x = y\sin{y}.

    You can not isolate the y's.
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  3. #3
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    hmm...

    Actually, I also thought inverse of f(x)=xsinx does not exist; however, my math teacher sent e-mail back to me like this

    "at minimum you should be able to define it -pi/2 to pi/2 at least. I know that it would be a very complex function to define the whole thing, but intervals I think should be possible."
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  4. #4
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    What your teacher means is that you should be able to state the domain for which f(x) is one-to-one, so that the function will have an inverse.

    The inverse function IS defined as x = y\sin{y} - I just haven't specified its domain... I'm just lazy...
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  5. #5
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    I don't...really get it. Can you please show me how to get domain?
    Thank you
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  6. #6
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    Quote Originally Posted by Kyaoo View Post
    hi..
    I have a question about how to get the inverse of f(x)=xsinx
    This is for my extra credit on AP Calc class
    Thank you very much
    If it's for extra credit then it's meant to be your own work, not someone elses. This thread has already told you what to do. Sorry but no more help can be given. Thread closed.
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