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Homework Help: Induction proof help

  1. Oct 16, 2008 #1
    I need to show that (n^5)/5 + (n^3)/3 + 7n/15 is an integer for all n.

    I tried induction that obviously work for 1 but i could not manage to show this for k+1. Any tips please?
    1. The problem statement, all variables and given/known data

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Oct 16, 2008 #2
    Re: proof

    try expanding the k+1 case. Pascals triangle is a huge help for figuring out how to expand it. After expanding and factoring, you should see the base case and your hypothesis.
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