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Math Help - is the negative sign part of x?

  1. #1
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    is the negative sign part of x?

    I have the function (this is exactly how it's written in the paper):

    f(x)= -x^2/(x^2-9)

    I need to know where exactly the negative is in the numerator:

    -(x^2)

    OR

    (-x)^2

    Which is right?

    Any help is appreciated!
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  2. #2
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    Quote Originally Posted by REWIND10 View Post
    I have the function (this is exactly how it's written in the paper):

    f(x)= -x^2/(x^2-9)

    I need to know where exactly the negative is in the numerator:

    -(x^2) Mr F says: This one.

    OR

    (-x)^2

    Which is right?

    Any help is appreciated!
    ..
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  3. #3
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    -\left(x\right)^{2} = -(x)(x)
    \left(-x\right)^{2} = (-x)(-x)= xx
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  4. #4
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    it is easy , the function is written : f(x)= -x^2/(x^2-9)
    so the negative can be for either numerator or denumerator .. as a numerator , it is -X^2 so it gonna be f(x) = (-(x^2))/(x^2-9)
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  5. #5
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    As mosta86 said, it doesn't matter:
    \frac{-x^2}{x^2-9}= \frac{x^2}{-(x^2- 9)}= -\frac{x^2}{x^2- 9}.

    In none of those, however, is this the same as \frac{(-x)^2}{x^2- 9}= \frac{x^2}{x^2- 9}.

    I suspect that the question should NOT have been "is the negative in the numerator?" (the answer to that is "it doesn't matter") but "is the negative part of what is squared?". The answer to that is NO! For example, -2^2= -(2)(2)= -4 NOT (-2)(-2)= 4.
    Last edited by mr fantastic; November 21st 2009 at 08:38 PM. Reason: Fixed some latex
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