What topics should DEFINITELY be covered in multivariable calculus and differential equations? My calc 3 course completely overlooked Lagrange Multipliers and Greens Theorem. I had to teach myself what a Jacobian was. I want to be sure that I am familiar with the subject but it's hard to find an accurate representation of what should be covered in an extensive course. It's specifically difficult to find DE topics, since there are frankly, so many.