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Homework Help: Summation - Im new to this

  1. Jun 8, 2009 #1
    Summation (-1)[tex]^{i}[/tex] [tex]\frac{i^2+i+1}{i!}[/tex]

    I guess im suppose to apply the summation rule

    and i got (-1)[tex]^{i}[/tex] [tex]\frac{n(n+1)(n+2)+3n}{3i!}[/tex]
  2. jcsd
  3. Jun 8, 2009 #2


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    What summation rule are you talking about?
    What is n in your final answer?
    How can it depend on i anyway, if you are summing over that?

    Please elaborate a bit more on how you wanted to solve the question.
  4. Jun 9, 2009 #3
    n is 2008.

    Im uncertain of the application of summation - factorial.
  5. Jun 9, 2009 #4


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    Could you answer CompuChip's first question? Secondly are you sure the sum is listed correctly, because when I plug it into mathematica it gives a pretty terrible result. Not something one new to summations would be expected to do.
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