In article <firstname.lastname@example.org>, IV <email@example.com> wrote: > >It seems that computer algebra systems like Maple (version 11) and >Mathematica (version 7) can not solve all simply solvable equation systems >automatically. Let us look e.g. at the equation system [c1=A*B/C, c2=C*A/D, >D=c3-A, C=A-B], where c1, c2 and c3 are real or complex constants, A, B, C >and D are real or complex variables, and the solutions for the variable A >are wanted. The equation system forms a cubic equation in A, and the >solutions of the equation system are the solutions of this cubic equation. >But the solve command can find neither the cubic equation nor its solutions. >I think, the equation system has to be somehow prepared to yield a normal >form of equation systems. Is a normal form for polynomial equation systems >known?
As Axel Vogt has pointed out, solving this system is straightforward in Maple, and I suspect in Mathematica as well. Probably you did not enter the commands correctly.
Axel presented his solution in Maple 17. Since you mentioned Maple 11, I tested the same on Maple 11. Works fine.