integrate(exp(x^3), x, 1, 2) (Was Re: couple of questions about complex expressions)
Subject: integrate(exp(x^3), x, 1, 2) (Was Re: couple of questions about complex expressions)
From: Raymond Toy
Date: Tue, 25 Sep 2012 14:48:10 -0700
On Tue, Sep 25, 2012 at 8:49 AM, Robert Dodier <robert.dodier at gmail.com>wrote:
>
> PS. Seems like domain:complex is enough to get the result
> I was looking for:
>
> (%i2) domain : complex $
> (%i3) integrate (exp (x^3), x, 1, 2);
> (%o3) ((-1)^(2/3)*gamma_incomplete(1/3,-8)-(-1)^(2/3)
> *gamma_incomplete(1/3,-1))/3
> (%i4) %, numer, expand;
> (%o4) 275.5109837633115-7.71234927772942E-14*%i
>
Didn't this issue come up before a few months ago?
I find it quite annoying that you have to specify domain:complex to get the
correct answer for an integral that has a purely real integrand and should
give a purely real result.
Ray
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