What Definite Integral Does This Riemann Sum Represent?

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SUMMARY

The Riemann sum Rn = ∑(i * e^(-2i/n))/n^2, where i ranges from 1 to n, represents the definite integral of the function f(x) = x * e^(-2x) over the interval [0, 1]. The sum can be interpreted as approximating the area under the curve defined by this function as n approaches infinity. The key to solving this problem lies in recognizing the relationship between the Riemann sum and the integral, specifically how the terms in the sum correspond to the function evaluated at specific points within the interval.

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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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