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Math Help - show that the function is not 1-1

  1. #1
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    show that the function is not 1-1

    Show that the function f(x)=2 x^3+3 x^2+17 is not 1-1 on the interval [-1,1].
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  2. #2
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    It has a minimum at x=0...
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  3. #3
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    Quote Originally Posted by maddas View Post
    It has a minimum at x=0...
    I'm sorry I made a mistake its x^3-3x^2+17. I'm guessing it would be the same? But isn't the minimum at x=1?
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  4. #4
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    Yes, same idea, that one still has an extremum in the interior of [-1,1] (at x=0).

    edit: wait, who asked this question??
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  5. #5
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    Quote Originally Posted by alice8675309 View Post
    I'm sorry I made a mistake its x^3-3x^2+17. I'm guessing it would be the same? But isn't the minimum at x=1?
    Hm that's pretty strage since I posted this question. Lol but what I have originally posted is the question. Weird.
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  6. #6
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    ...bro, be honest with me. Do you have split personalities or something? Are they all working on different questions?
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  7. #7
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    Quote Originally Posted by maddas View Post
    ...bro, be honest with me. Do you have split personalities or something? Are they all working on different questions?
    LOL! Nah that was completely random and stra ge..I haven't the slightest clue who that person is. When I saw it I was like what in the world is going on?? O well lol
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