Depending on what you mean by "expression" you could try:
is (ratsimp(r-s)=0);
you could also try evaluation at random points.
you could take a derivative of r-s. If it comes out zero, then
r-s is a constant. If you can show that for one value of x and y
that r-s is zero, then the constant is zero.
This is the basis for the program zeroequiv.
there are other simplification programs like trigexpand, trigreduce,
exponentialize, radcan, ...
Lars Jensen wrote:
> How do I use maxima to test whether two expressions are equal? To give
> a trivial example, how do I check with maxima that the two expressions
> x + 3y is the same as 3y + x or x + 2 + 3y -2 ?
>
> Thanks for any answers.
> Lars.
>
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