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Homework Help: Difficult equation expansion

  1. Apr 18, 2007 #1
    I have the following polynomial equation:

    [tex]p = \frac{8x + 16xw + 8xw^2 - 3w^3}{2 + 7w + 8w^2 + 3w^3}[/tex]

    The next step is to let x=0 and expand p in powers of w.

    The result is

    [tex]p = -(3/2)w^3 +...[/tex]

    Someone knows how to make this expansion?
    I don't understand where this first term comes from.
    Last edited: Apr 18, 2007
  2. jcsd
  3. Apr 18, 2007 #2


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    Divide the numerator by the denominator (after putting x=0). Sorry if that sounds obvious, but just do it. Just like you were dividing polynomials back when you were young. The first term you will see is the one you don't understand.
  4. Apr 18, 2007 #3
    Thanks a bunch. Duh... I feel pretty stupid now. That is what I get for working long nights :)

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