<s>[INST] This is not homework, I just want to make sure I'm not misunderstanding the concept. I'd like to do a few problems to practice. But I need help with how to set up the problems. 

If we're finding the area of the region between two curves, how do we know when to set up the problem as an integral from a to b of [f(x) - g(x)]dx versus an integral from a to b of [g(x) - f(x)]dx?[/INST]