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Homework Help: Summation inside a summation inside a summation

  1. Sep 15, 2012 #1

    I know how to do it normally, but this confuses me. Can you show me how to do it? And what were the steps you took... etc. Initially, I thought of putting them inside brtackets and work out the last one at the right first, but I'd need to know what K and J are, it's confusing. Can anyone make this clear for me?


    I tried this, but it doesn't seem like I'm on the right track.
    Last edited: Sep 15, 2012
  2. jcsd
  3. Sep 15, 2012 #2

    But I also solved it with a calculator and it says the answer is 81. What am I doing wrong?
  4. Sep 15, 2012 #3
    Nevermind. I figured it out. :D

  5. Sep 15, 2012 #4


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    1-1+1 = 1 not -1 ... that's if you mean i - j + k and not i - (j + k) .
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