(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

find the integral from (2 to infinity) of 1/(1+e^x)

2. Relevant equations

3. The attempt at a solution

lim(t-->infinity) integral from (2 to t) of 1/(1+e^x)

1/1+e^x = (1+e^x-e^x)/(1+e^x)

= 1-e^x(1+e6x)

when you solve the integral:

x-ln(1+e^x) between 2 and t

t-ln(1+e^t)-(2-ln(1+e^2))

here we're confused, because when you plug in t=infinity, you end up with a limit that doesn't exist... help?

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# Homework Help: Indefinate integral

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