http://www.khanacademy.org/math/calculus?k Can I get honest opinions from the professional physicists out there? Will the course at that link give me a basic enough grounding in calculus to understand everything up to say SR, GR, QED and QCD? I've got the required maths up to trigonometry. And yes, my studies will have to be self-taught. No, I'll not be more than an amateur in my studies. I just want to be able to work out the maths behind some of the most basic phenomena behind our existence; right now, I just have to take a person at their word. Which isn't very satisfying as you can imagine. :) Thanks for your insights.