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General Exapansion

  1. Apr 7, 2009 #1
    Hi Guys,
    I have been asked to do expand E[(1-tX)^-1] for the first 3 terms
    Is there are good formula to use to do this?

    with the value E, I take it is is the Expected Value. does that get included in the expansion?
  2. jcsd
  3. Apr 8, 2009 #2
    You need to use the fact that
    [tex] \mathbb{E}[f(X)]=\int_{\mathbb{R}}f(x) \mathbb{P}(X \in dx)[/tex]
    and the binomial expansion using the linearity of the integral.
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