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Homework Help: Simplifying Summations

  1. May 19, 2008 #1
    1. The problem statement, all variables and given/known data

    I'm trying to simplify a summation. I have something that looks like


    \sum \sqrt{(1/4)(i)} (1/4)

    Granted I might have made a mistake setting this up which would make my question irrelevant but anyway.

    2. Relevant equations
    there are equations for i, i squared and i cubed

    3. The attempt at a solution

    I don't think theres an equation for the square root of i, so can i square the whole problem to make it just i?

    So it would be like...


    \sum \((1/4)(i)(1/16)
    Last edited: May 19, 2008
  2. jcsd
  3. May 19, 2008 #2
    What are you summing, and where is the i?
  4. May 19, 2008 #3
    I typed x instead of i, i just showed one part of the problem, i just want to know if you can just square the whole thing
  5. May 19, 2008 #4
    does it work if u plug in numbers?

    like 1+2+3+4 = 10 .. (edit: not 5) lol

    It should not work (using my guessing power)
  6. May 19, 2008 #5


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    Is 'i' the variable in the summand which goes from say i=0 to some i=N, or does it denote the square root of -1? I really don't get what you are summing up here. You said there's 'x', so where is it?
  7. May 19, 2008 #6


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    You definitely can't 'square it' in the way you are thinking about. You can approximate it pretty well if the upper limit is large. Maybe you should tell us what the actual problem is. As you said, this particular issue may be irrelevant.
  8. May 19, 2008 #7
    from her comment: "there are equations for i, i squared and i cubed "

    I think she wants a formula for i^0.5 ...

    I don't think there's any
  9. May 19, 2008 #8


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    I don't think there is any either. That's why I suggested telling us the original problem. KatieLynn probably doesn't really need one.
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