solving equations




On Fri, 26 Feb 2010, Janek Kozicki wrote:

< Hi,
< 
< I am starting to learn maxima. The best is to do by examples. So I
< have those equations:
< 
< eq1:x^2/a^2+y^2/b^2=1;
< eq2:A(x-x0)+B(y-y0)=0;

I think that you are missing the multiplication operator * after A and
B. Maxima parses eq2 as two (undefined) functions sum to 0.



< 
< And I want to solve them for A and B. I have the solution in front of
< me in the notebook, I just want maxima to do it now, to see how it
< works. So in my notebook I do following things:
< 
< eq3:(eq1-1)*(a*b*B)^2;
< eq4:eq3+eq2;
< 
< B_result:solve(eq4,B);
< 
< And here I'm stuck. I would expect maxima to calculate
< Delta=b^2-4*a*c with respect to B. And show two answers for B.
< But it does not.

See my comment above. I get

a^2*b^2*(y^2/b^2+x^2/a^2-1)*B^2+(y-y0)*B+(x-x0)*A = 0

a quadratic in B. Maxima (solve) gives me two solutions to this
equation in B.

Welcome to Maxima.

Leo
 

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