Open rtoy opened 3 months ago
rtoy
commented
3 months ago Imported from SourceForge on 2024-07-07 13:39:46 Created by nobody on 2008-10-14 09:09:19 Original: https://sourceforge.net/p/maxima/bugs/1474/#d480
I don't know if it is related, but I have a much simpler example of the same behaviour :
(%i14) solve( [e^x=0],[x] ); (%o14) [e^x=0]
but
(%i15) solve( [e^(-x)=0],[x] ); (%o15) []
The latter is correct.
rtoy
commented
3 months ago Imported from SourceForge on 2024-07-07 13:39:49 Created by herminio_gomes on 2008-12-11 23:29:38 Original: https://sourceforge.net/p/maxima/bugs/1474/#92bd
I found this with this equation: (2*%pi*r*R*sqrt(R^2-r^2)+2*%pi*r*R^2-3*%pi*r^3)/(3*sqrt(R^2-r^2))==0 for variable r. Same bug -> "r" involves "r" in the solution.
Mathematica solves it correctly. Herminio Gomes
Imported from SourceForge on 2024-07-07 13:39:45 Created by *anonymous on 2008-08-07 19:33:02 Original: https://sourceforge.net/p/maxima/bugs/1474
I entered the following function definitions:
N(a,b,g):=sqrt((g+a+sqrt((g-a)^2+b^2))/2); n(a,b,g,mr,mi):=sqrt((mr^2+mi^2)N(a,b,g)^2-mi(mr b-mi a))/mr;
and tried to solve the equation in terms of g:
solve(n(a,b,g,mr,mi)^2=g,g);
the result was
[g=-(a*(mr^2+3*mi^2)+sqrt(g^2-2*a*g+b^2+a^2)*(mr^2+mi^2)-2*b*mi*mr)/(mi^2-mr^2)]
The problem is that the solution involves g. I know there are solutions, because Mathematica could find 4 of them in terms of a, b, mr, and mi only.