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Thread: Can I do it like the proof for sqrt of 2

  1. #1
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    Can I do it like the proof for sqrt of 2

    Prove that there is no rational root whose square is 12?
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  2. #2
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    Quote Originally Posted by Nichelle14
    Prove that there is no rational root whose square is 12?
    I use the proof based on Euclid's Method.
    Do you know that one? It is completely analogous answering your question "Can it do it like sqrt of 2?".
    --------
    Look here
    I can show you how to use this theorem to prove that it irrational.
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  3. #3
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    no I do not know.
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  4. #4
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    How are
    Susie38 and Nichelle14 Related?
    Are you the same user?
    ------
    Note, what I prove in that thread in the end is this. "That a square root of an integral number is either integral or irrational"

    Note that there is no integer such as, $\displaystyle x^2=12$ why? Very simple, note the first few values,
    $\displaystyle 1^2=1,2^2=4,3^2,=9,4^2=16$ it never gives 12, since anything thing greater then 4, will for certainly give a value greater than 12 because this sequence of square are increasing they are simply to big to be equal to 12, thus there is no such $\displaystyle x$. Thus, by the theorem its root must be irrational.
    Last edited by ThePerfectHacker; Jun 11th 2006 at 06:44 PM.
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  5. #5
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    yes. the same. I forgot my password, but figured it out. Does it matter? Should i only use one? Also it depends on what computer i log in at home. I don't always pay attention to what my user name is at the time. My computer automatically remembers the user name and password.
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  6. #6
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    Quote Originally Posted by Susie38
    yes. the same. I forgot my password, but figured it out. Does it matter? Should i only use one? Also it depends on what computer i log in at home. I don't always pay attention to what my user name is at the time. My computer automatically remembers the user name and password.
    No, no problem. Your IP matches so I assumed you were the same.
    You can ask the administrator to reset your password, if that is necessary. Also, you can sent yourself an e-mail with the password.
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