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Homework Help: Closed form solution

  1. May 18, 2010 #1
    1. The problem statement, all variables and given/known data

    Find the closed form value for

    SIGMA e^(i/n)
    i= 0

    2. Relevant equations


    3. The attempt at a solution

    summation expands to
    1 + e^(1/n) + e^(2/n) - - - - - e^1

    To be honest i have no clue how to go about these kinds of problems so a general help would be nice.

  2. jcsd
  3. May 18, 2010 #2


    User Avatar
    Science Advisor

    Try writing [tex]e^\frac{1}{n} = x, e^\frac{i}{n} = x^i [/tex], and see where that leads you.
  4. May 18, 2010 #3


    Staff: Mentor

    Might this be a geometric series?
  5. May 18, 2010 #4


    User Avatar
    Science Advisor

    Looks like it to me!
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