- summary: integrate(1/(x+a),x) is incomplete --> integrate(1/(x+a),x) missing abs
presently integrate(1/(x+a),x) returns log(x+a)
It should return log(abs(x + a))
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On the reals integrate(1/x,x) == log(abs(x)) is okay, but on
the complex plane, it's wrong. For one, abs isn't differentiable
anywhere in the complex plane. If you run into a problem and
think you need log(abs( .... )), try logcontract.
Barton
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When the logabs == true, you get the value you want.
I'll change the status of this bug to 'resolved.'
(%i1) integrate(1/(x+a),x), logabs : false;
(%o1) LOG(x + a)
(%i2) integrate(1/(x+a),x), logabs : true;
(%o2) LOG(ABS(x + a))
(%i3) build_info();
Maxima version: 5.9.0.9beta2
Maxima build date: 7:39 9/1/2004
host type: i686-pc-mingw32
lisp-implementation-type: Kyoto Common Lisp
lisp-implementation-version: GCL 2.6.5
Barton
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user_id=501686
Closing this report as "Won't fix" since it's apparently not
a bug according to discussion below.
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