solving simple systems of equations manually



On 03/29/2012 06:51 AM, Tamas Papp wrote:
> Hi,
>
> This is a newbie question, I am still learning Maxima.  I know a bit
> of CL.
>
> I have the following system:
>
> /* equations */
> eq1: r*U = b+lambda_u*(W0-U);
> eq2: r*W0 = w0 + lambda_e*(W1-W0) + sigma*(U-W0);
> eq3: r*W1 = p + sigma*(U-W1);
> eq4: W0-U=beta*(W1-U);
>
> The unknowns are W0, W1, U, and w0.  I am interested in the expression

You've got W0 listed twice? what did you mean here?

>    (w0-b)/(w1-w0)

> Using economic intuition about this problem, we want to write
> everything in terms of S=W1-U.  So I did the following:

ratsubst(S,W1-U,expr) may be a good way to make this transformation 
(where expr is the expression you want to make the change in).

I'm afraid that the overall goal you're seeking is a little confusing 
based on your description.