Just brought this topic back up because I was able to acquire a copy of Mathematica 3.0 just today (from the IMF staff library); this thing is just
incredible. It was able to do just about every integral I could throw at it (except for the x^x one, but I don't know of anything that can do that), solve a bunch of really hard 4-variable partial differential equations in less than a second (which would have taken me months), and do some very nice implicit 3D plots in spherical coordinates. I will definitely upgrade to version 4 soon, which is the latest one. If you're into math, I would definitely recommend this package.


Oh BTW here's a graph of the first equation up there: (x²-y²)^(y³/x³) = (sin(x³) cos(y³))^(cos(x²) sin(y²))
(yes, it is only one equation

)

Zoomed in view: first quadrant, origin is at the bottom-left corner

The fun part is finding a derivative and an integral for it...

(have not been able to get an exact indefinite integral, or the solution to dy/dx=f(x,y) here, but it might still be possible; going to keep working on that one)