What principles apply when making a substitution of variables in an improper integral. I gather that a substitution of variables can change an impoper integral to a proper integral. Can substitution also change a proper integral into an improper integral? Suppose I know that a pair of integrals are each to be evaluated over the whole real line, and that one can be obtained from the other by a change of variable; in that case, can I ignore the issue of how, if the domain of integration had been finite, the limits would change?(adsbygoogle = window.adsbygoogle || []).push({});

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# Substitution of variables in improper integrals

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