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rtoy / maxima

A Clone of Maxima's repo
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triple integrate fails #2454

Open rtoy opened 4 months ago

rtoy commented 4 months ago

Imported from SourceForge on 2024-07-06 09:21:13 Created by andrea_latina on 2017-11-12 20:44:15 Original: https://sourceforge.net/p/maxima/bugs/3351

My Maxima (version="5.39.0",timestamp="2017-11-11 10:08:23",host="x86_64-apple-darwin16.7.0",lisp_name="SBCL",lisp_version="1.4.1")

(macports, Sierra)

fails to integrate:

integrate(integrate(integrate(1/sqrt(x^2+y^2+z^2),x),y),z)

[ whereas Mathematica succeeds, with this result:

r:sqrt(x*x+y*y+z*z);
(2*x*y*log(z+r)-x^2*atan((x*z)/(y^2+r*y+x^2))-y^2*atan((y*z)/(y^2+x^2+r*x))-2*x^2*atan((y*z)/(r*x))-2*y^2*atan((x*z)/(r*y))+2*y^2*
atan(z/y)+3*x^2*atan(z/x)+(atan(y/z)-atan((x*y)/(r*z)))*z^2+y*(2*log(x+r)*z-3*z)+2*x*log(y+r)*z-2*x*z)/(2)

]

rtoy commented 4 months ago

Imported from SourceForge on 2024-07-06 09:21:14 Created by andrea_latina on 2017-11-12 21:18:13 Original: https://sourceforge.net/p/maxima/bugs/3351/#e6df

I repeat here the expression... 

r:sqrt(x*x+y*y+z*z);
(2*x*y*log(z+r)-x^2*atan((x*z)/(y^2+r*y+x^2))-y^2*atan((y*z)/(y^2+x^2+r*x))-2*x^2*atan((y*z)/(r*x))-2*y^2*atan((x*z)/(r*y))+2*y^2*
atan(z/y)+3*x^2*atan(z/x)+(atan(y/z)-atan((x*y)/(r*z)))*z^2+y*(2*log(x+r)*z-3*z)+2*x*log(y+r)*z-2*x*z)/(2)
rtoy commented 4 months ago

Imported from SourceForge on 2024-07-06 09:21:17 Created by robert_dodier on 2017-11-16 23:01:26 Original: https://sourceforge.net/p/maxima/bugs/3351/#b323

Enclosing code in four tildes for formatting.