Re: Simple question from a biologist

*To*: mathgroup at smc.vnet.net*Subject*: [mg67151] Re: Simple question from a biologist*From*: Jean-Marc Gulliet <jeanmarc.gulliet at gmail.com>*Date*: Sun, 11 Jun 2006 02:16:57 -0400 (EDT)*Organization*: The Open University, Milton Keynes, UK*References*: <e6e27d$1tp$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

tnad wrote: > I'm a bit new to this so please bear with me. I solved this eqation: > > Sol = Solve[{{{-x, 0, z}, {x, -y, 0}, {0, y, -z}}.{A, B, C} == 0, A + B + C == 1}, {A, B, C}] > > and got the ouputs of A, B and C interms of x,y, and z each. > > Now I want to express a term called "rate" where rate = Ax = By = Cz in terms of x, y and Z only. > > So I tried to do this: > Solve[rate == Ax , rate] /. Sol > > but I cannot get the rate in terms of x,y and z. > Is there a better way to do this? Also if someone knows of a better tuttorial (better than the built-in tuttorial) for mathematica, please let me know. > Do you mean something like Out[2]? In[1]:= sol = Solve[{{{-x, 0, z}, {x, -y, 0}, {0, y, -z}} . {A, B, C} == 0, A + B + C == 1}, {A, B, C}] Out[1]= y z x z {{A -> ---------------, B -> ---------------, x y + x z + y z x y + x z + y z x y C -> ---------------}} x y + x z + y z In[2]:= Solve[rate == A*x, rate] /. sol[[1]] Out[2]= x y z {{rate -> ---------------}} x y + x z + y z HTH, Jean-Marc