Solved: Closed Form Solution for SIGMA e^(i/n)

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Homework Statement



Find the closed form value for

n
SIGMA e^(i/n)
i= 0

Homework Equations



?

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.

Thanks
 
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Try writing e^\frac{1}{n} = x, e^\frac{i}{n} = x^i, and see where that leads you.
 
Dissonance in E said:

Homework Statement



Find the closed form value for

n
SIGMA e^(i/n)
i= 0

Homework Equations



?

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.

Thanks

Might this be a geometric series?
 
Looks like it to me!
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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