Solving a system of equations
- To: mathgroup at smc.vnet.net
- Subject: [mg103211] Solving a system of equations
- From: Maki Takahashi <maki at physics.usyd.edu.au>
- Date: Thu, 10 Sep 2009 07:24:03 -0400 (EDT)
Hi,
I'm a beginner with Mathematica (working interactively) and I'm trying
to solve a system of nonlinear vector equations.
I have several questions:
1) I am working in spherical polar coordinates where each symbol r,
theta and phi are functions of a variable lambda. I have N of these, so
I have declared a function like:
x[i_] := {(\[Lambda] // Symbol[StringJoin["r", ToString[i]]])*
Cos[\[Lambda] // Symbol[StringJoin["\[Theta]", ToString[i]]]]*
Sin[\[Lambda] // Symbol[StringJoin["\[Phi]", ToString[i]]]],....
this allows me to have symbols like r1\[Lambda], r2\[Lambda],
r3\[Lambda]...
I'm sure there is an easier way any suggestions. I need the functional
dependence as I will be taking derivatives of these.
2) When is it best to set the limits of the variables r, theta and phi?
when I declare x[i_]?
or when I am trying to solve my system of equations?
3) I have composed my system of vector equations using x[i_] and their
derivatives and I wish to solve for a set of unknowns. Say 1 of the
equations is called EOM1 which has 3 components. How do I solve these?
EOM1 = = {a1,a2,a3}
I have a few more questions but I leave it at that for now,
thank you very much for your help
Maki