Try using 'subst' to substitute values for a1, a2, r1, and r2.
Something like
exp1 : a1*s*h1=(h2-h1)/r1 +u;
exp2 : a2*s*h2 = -(h2 -h1)/r1 - h2/r2;
subst([a1=1,a2=1,r1=1/2,r2=1/3],[exp2,exp1]);
solve(%,[h1,h2]);
should work.
BW
-----maxima-bounces at math.utexas.edu wrote: -----
>To:
>From: Doug Stewart
>Sent by: maxima-bounces at math.utexas.edu
>Date: 10/22/2007 07:49PM
>cc: maxima at math.utexas.edu
>Subject: beginner question
>
>I have
>
>
>exp1:a1*s*h1=(h2-h1)/r1 +u;
>exp2:a2*s*h2 = -(h2 -h1)/r1 - h2/r2;
>a1=1;
>a2=1;
>r1=.5;
>r2=1/3;
>solve([exp2,exp1],[h1,h2]);
>
>and this works but now I want to use the numerical values for a1 a2 r1
>r2.
>
>How do I get a final answer.
>Thanks
>Doug Stewart
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