/sci/ - Science & Math

I did up to calculus 3/linear algebra in college and am interested in going back to school for applied mathematics. I'd like to try and get the ball rolling myself again but I'm not sure how much review is needed. I've heard real analysis is the first major roadblock people run into so I'd like to start studying that myself, how much review from calculus would be required before I can do that? Do I need to finish a basic proofs book beforehand?