Lazy math program?

Question

I'm writing a software that does simple mathematical calculations for lazy people.

I need ideas. I already wrote some pieces of code that calculates 'Quadratic formula', but I have no idea what to do next.

Answer 1

I'm with Jonas T, I don't know why he didn't make his comment an answer.

Symbolic integration of polynomials would be an easy next step.

I disagree somewhat with Raphael. Coding some simple functions can give you a better appreciation when you do use something like WolframAlpha.