Maxima asks about sign of integration(!) variable



Hi,
I agree, Maxima should not ask you about the sign of x in this case; to 
get the correct result for that integral you actually have to separate 
it into two parts:

(%i2) expr : sqrt(1+(4*x^(1/3)-1/16*x^((-1)/3))^2)$
(%i3) integrate(expr, x, -8, 0) + integrate(expr, x, 0, 512);
(%o3) 98739/8

(no questions asked). The other problem (Maxima keeps asking the same 
question again two more times) is a bug in versions 5.30.0 and 5.31.0. 
The latest release (5.31.1) does not have that bug.

Regards,
Jaime

On 25-09-2013 09:08, David Scherfgen wrote:
> Hi,
>
> when I do:
>
> expr : sqrt(1+(4*x^(1/3)-1/16*x^((-1)/3))^2);
> integrate(expr, x, -8, 512);
>
> Maxima asks "Is x positive or negative?".
> Why does it ask that? x is the integration variable ... it shouldn't 
> ask anything about it.
>
> Also, when I answer "positive;", Maxima keeps asking the same question 
> again two more times.
> Only then, it gives me an answer.
>
> The whole asking thing seems very buggy to me ...
>
> David
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