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Topic: question on when definte integral evaluates, but indefinite does not.
Replies: 2   Last Post: Nov 14, 2017 5:21 AM

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 Nasser Abbasi Posts: 6,677 Registered: 2/7/05
question on when definte integral evaluates, but indefinite does not.
Posted: Sep 20, 2017 11:41 PM

How is it possible that CAS can evaluate an integral
symbolically when it is definite, but not able to
when it is indefinite? This is all symbolic integration,
not numerical ofcourse.

Here is an example:

Assuming[Im[p] != 0, Integrate[1/(E^z^2*(p - z)),{z, -Infinity, Infinity}]]

(Pi*Erfi[p] - Log[-(1/p)] - Log[p])/E^p^2

But

Assuming[Im[p] != 0, Integrate[1/(E^z^2*(p - z)), z]]

Returns unevaluated.

I tried the above on Maple, but could not make it give same result,
it return unevaluated for both cases.

Mathematica 11.2

--Nasser

Date Subject Author
9/20/17 Nasser Abbasi
9/21/17 Richard Fateman
11/14/17 drhuang57@gmail.com