I am a lecturer at a Technicon (more or less the same thing as a community college in the States) in South Africa, busy with a "intelligent" calculus program that'll not only give students the right answer, but actually show them where they have gone wrong. That's the theory, anyway.
What i need is the C++ code for doing the calculus. Although I suppose I can write this myself, I don't want to re-invent the wheel. I don't need very advanced stuff - just basic differentiation, integration and first order differential equations.
Can somebody point me to a website or maybe a person(s) that has done this before?