On Thu, Oct 14, 2010 at 12:35 PM, egc <cooch17 at verizon.net> wrote:
> f:=lamda^2-lambda*c-a*lambda+a*c-b^2=0
> To implicitly differentiate lambda with respect to? in Maple, I'd simply
> enter
> implicitdiff(f,lambda,c)
> yielding
> ?(a-lambda)/(-2lambda+c+a)
> There is no straight equivalent in Maxima for the implicitdiff command in
> Maple (not that I can find).
I don't know of one either.
> So, how does one do simple implicit differentiation in Maxima? Is there a
> simple 'single command' to do the trick, or do I have to break up the
> problem in pieces, somehow?
This seems to do what you want:
depends(lambda, c);
f : lambda^2 - lambda*c - a*lambda + a*c - b^2 = 0;
foo : diff(f, c);
fim : solve(foo, diff(lambda, c))[1]; /* solve returns a list of
solutions, but there's just one in this case */
If you want just the right-hand side of the result in an expression,
that's just:
just_rhs_expr : rhs(fim);
I suppose you could wrap that in a little Maxima function for your
students if you wanted.
Happy Maxima'ing!
--
Joshua Stults
Website: http://j-stults.blogspot.com