What Definite Integral Does This Riemann Sum Represent?

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The Riemann sum Rn = ∑(i*e^(-2i/n))/n^2 represents a definite integral that can be identified by recognizing the function involved. The sum can be expressed in terms of a function f(x) that corresponds to the interval being divided into n pieces. To solve the problem, one must manipulate the terms within the brackets to reveal the underlying function. The key is to relate the index i to the partition of the interval and the values of the function at those points. Ultimately, the goal is to identify the definite integral that this Riemann sum converges to as n approaches infinity.
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Homework Statement



Rn=\sum(i*e^(-2i/n))/n^2, i=1

Identify this Riemann sum corresponding to a certain definite integral.

Homework Equations





The Attempt at a Solution



I got till 1/n^2 [1/e^(2/n)+2/e^(4/n)+3/e^(6/n)...n/e^2]

and that's it. To my understanding I should be able to pull something else out of the square brackets but I tried so long with no success.

Help?
 
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Actually, you want to put something back into the square bracket.

Your function f(x) is going to turn into summing up values of the function that looks like f((b-a)i/n) because you break up the interval into n pieces and sum over the value on each piece. So your objective is to pair up i's and n's
 
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