1 Mar 02:45 2003

### Re: New user question

David and Michele Holmgren <holmgrenm <at> shaw.ca>

2003-03-01 01:45:52 GMT

2003-03-01 01:45:52 GMT

Hi - Even if you try eliminate([f1,f2],[B]) or eliminate([f1,f2],[F]), you get some very ugly expressions which seem to defy simplfication or solution. Also eliminate([f1,f2],[B,F]) produces [0] as a result. So, this system may defy symbolic solution (unfortunately), and a numerical method seems the only recourse. Dave Holmgren > > I'm new to Maxima > > Thanks for your interest in Maxima! > > > f1: (Rb/Bmin) * B * (B - Bmin) * (1 - B/Bmax) - A * B * F = 0; > > f2: (Rf/Fmin) * F * (F - Fmin) * (1 - F/Fmax) - A * B * F = 0; > > res: solve ([f1, f2], [B, F]); > > > > Now if I input just that, and try to solve it symbolically, > > Maxima hangs. > > I think you have found a bug. > > Your system reduces to something of the form: > > q1: b2 * B^2 + b1 * B + b0 + bf * F = 0 > > q2: f2 * F^2 + f1 * F + f0 + fb * B = 0 > > and Maxima seems to run forever on that, too. > > I tried solving the system step by step.(Continue reading)