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Math Help - Inverse function

  1. #1
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    Inverse function

    Hi MHF, knowing that the quadratic function does not admit inverse, and that \left |  X\right | = \sqrt[2]{x^{^2}} a modular function have inverse? if yes, how can i find for example y= |x+2|-|3x+2|.
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  2. #2
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    Re: Inverse function

    Quote Originally Posted by Chipset3600 View Post
    Hi MHF, knowing that the quadratic function does not admit inverse, and that \left |  X\right | = \sqrt[2]{x^{^2}} a modular function have inverse? if yes, how can i find for example y= |x+2|-|3x+2|.
    Functions can only have inverses if they are one-to-one on their domain. It's pretty obvious that the example you gave is not one-to-one.
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    Re: Inverse function

    Quote Originally Posted by Prove It View Post
    Functions can only have inverses if they are one-to-one on their domain. It's pretty obvious that the example you gave is not one-to-one.
    But how can i see if the domain is one to one?
    So assuming it to be y = | x |?
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    Re: Inverse function

    Quote Originally Posted by Chipset3600 View Post
    But how can i see if the domain is one to one?
    So assuming it to be y = | x |?
    Have you ever heard of the horizontal line test?
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  5. #5
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    Re: Inverse function

    Quote Originally Posted by Prove It View Post
    Have you ever heard of the horizontal line test?
    that when I draw a horizontal line can only intercept function in only 1 point.
    So the modular function it will never be one to one?
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  6. #6
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    Re: Inverse function

    What is |2|? What is |-2|?

    A function is either one-to-one or it is not. I don't know what you mean by "never be". You don't think it is sometimes one-to-one and sometimes not?
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  7. #7
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    Re: Inverse function

    |2|=|-2|=2... The doubt is If there is any modular function that admits inverse?
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