#11941: Solve and assumptions too aggressive with cube root of negative numbers
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Reporter: kcrisman | Owner: burcin
Type: defect | Status: new
Priority: major | Milestone: sage-4.8
Component: symbolics | Keywords:
Work_issues: | Upstream: N/A
Reviewer: | Author:
Merged: | Dependencies:
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Comment(by kcrisman):
Well, in general we do ''not'' want to do this. It's been discussed ad
nauseam [http://groups.google.com/group/sage-
support/browse_thread/thread/66d45649ca8c1cc3?pli=1 many]
[http://ask.sagemath.org/question/260/fractional-power-to-negative-number
times], and the sense is that:
* Similar programs don't necessarily do this
* {{{(-1)^(1/3)}}} is not really `-1` but a primitive complex root of
`-1`.
This ticket is about the fact that Maxima returns three solutions to the
equation, but when we do the `assume(x,'real')` they ''all'' mysteriously
vanish!
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Ticket URL: <http://trac.sagemath.org/sage_trac/ticket/11941#comment:3>
Sage <http://www.sagemath.org>
Sage: Creating a Viable Open Source Alternative to Magma, Maple, Mathematica,
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