Since you are eyeing DEs, I would suggest not to spend too much time on Calculus. I have two resources in mind: Calculus Made Easy (available freely on Project

Since you are eyeing DEs, I would suggest not to spend too much time on Calculus. I have two resources in mind: Calculus Made Easy (available freely on Project Gutenberg) by Thompson, and simply Khan Academy. Paul Lamar has detailed notes on Calculus, too [0]. [0]: https://tutorial.math.lamar.edu/Classes/CalcI/CalcI.aspx https://tutorial.math.lamar.edu/Classes/CalcI/CalcI.aspx