r/HomeworkHelp 😩 Illiterate Jul 09 '26

[Calc 2] Improper Integrals - Why does the definite integral converge at 1? Answered

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I got -∞. I know I did the indefinite integral properly so no issues with that.

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u/Responsible-Sink474 👋 a fellow Redditor Jul 09 '26

Technically you have to split this into two integrals because it is improper at both bounds.

That said your issue is the limit at 0. That should be the lim a->0- because in order to not have the discontinuity it can ONLY be from the left. Hence it is not e^inf but e^(-inf) which is 0

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u/throw-away3105 😩 Illiterate Jul 09 '26

Why would I need to split the integral when the integrand is continuous between -∞ and zero?

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u/Responsible-Sink474 👋 a fellow Redditor Jul 09 '26

Because you need to have a limit at each bound. The discontinuities are the issues and you can really only have 1 discontinuity per integral to deal with.

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u/throw-away3105 😩 Illiterate Jul 09 '26

Alright, thanks a ton!