3 ms·

This series from 3blue1brown is also an excellent (re-)introduction. Maybe not deep enough to prepare you for relativity, though. https://www.youtube.com/play

• jeffreyrogers 6y ago
  His videos are good for giving intuition (I also liked the linear algebra ones), but it's really easy to fool yourself into thinking you understanding things better than you do, so you really need to work a lot of problems too.