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rtoy / maxima

A Clone of Maxima's repo
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integral of sine over real line is zero? #767

Open rtoy opened 1 month ago

rtoy commented 1 month ago

Imported from SourceForge on 2024-07-03 10:32:29 Created by kcrisman on 2014-10-07 10:04:01 Original: https://sourceforge.net/p/maxima/bugs/2819

Reported upstream at http://trac.sagemath.org/ticket/17109

(%i1) integrate(sin(x), x, minf, inf);
(%o1)                                  0

This seems problematic. Shouldn't it at the very least be ind or something like that?

rtoy commented 1 month ago

Imported from SourceForge on 2024-07-03 10:32:30 Created by rtoy on 2014-10-19 18:36:44 Original: https://sourceforge.net/p/maxima/bugs/2819/#72e9

FWIW, this fails because maxima recognizes that sin(x) is an odd function and then incorrectly decides that the integration of an odd function over the entire real line is always 0.

See initial-analysis in src/defint.lisp. Perhaps maxima should give up if the limits are minf to inf?