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#2168 solution not in domain, and others missed

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nobody
5
2012-11-18
2011-03-16
Anonymous
No

Maxima 5.23.2 http://maxima.sourceforge.net
using Lisp ECL 11.1.1
Distributed under the GNU Public License. See the file COPYING.
Dedicated to the memory of William Schelter.
The function bug_report() provides bug reporting information.
(%i1) solve([(2*x^2/(x^2 + y^2) + log(x^2 + y^2))*(x^2 + y^2)^x,2*x*y*(x^2 + y^2)^(x - 1)],[x,y]);
(%o1) [[x = 0, y = 0]]

This is not in the domain of the first expression. Further, there are four actual solutions which are not found.

(%i8) f(x,y):=(2*x^2/(x^2 + y^2) + log(x^2 + y^2))*(x^2 + y^2)^x;
2
2 2 2 x 2 2 x
(%o8) f(x, y) := (log(y + x ) + -------) (y + x )
2 2
y + x
(%i9) g(x,y):=2*x*y*(x^2 + y^2)^(x - 1);
2 2 x - 1
(%o9) g(x, y) := 2 x y (y + x )
(%i10) f(0,1);
(%o10) 0
(%i11) g(0,1);
(%o11) 0
(%i17) f(1/%e,0);
(%o17) 0
(%i18) g(1/%e,0);
(%o18) 0

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