>>14277679I would say if you're looking to brush up on old math, Khan Academy is great. That's really it though.
As far as actually learning new concepts goes, they don't offer difficult enough problems for you to practice with. If you want to learn calculus, I would suggest buying a Calculus textbook (I recommend Thomas' Calculus - Early Transcendentals), reading the chapters, taking notes, and doing the practice problems. That would be the most high quality method of learning calculus and getting GOOD at it. The book i suggested is also for Calc 1, 2, and 3, so it's a good value if you can afford it. You can also pirate it off Libgen if poorfag.
