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Homework Help: Binomal Expansion

  1. Jun 9, 2008 #1
    1. The problem statement, all variables and given/known data
    Expand in ascending powers of x upto and including the term x³:

    [tex]3(1-3x)^{-1} + 4(2+x)^{-2}[/tex]

    2. Relevant equations

    3. The attempt at a solution

    Err never done it with 2 terms like above before. Any suggestions/hints

    Thanks :)
  2. jcsd
  3. Jun 9, 2008 #2


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    Homework Helper

    expand [itex](1-3x)^{-1}[/itex] up to the term in [itex]x^3[/itex] and expand [itex](2+x)^{-2}[/itex] as well up to the term in [itex]x^3[/itex], the just add them.
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