[khedoros]

I learned some degree of linear algebra sometime during high school (in optional math classes that a lot of my schoolmates never reached), but mostly as a set of rote-learned operations without a connection to anything useful. As a consequence, I ended up re-learning a lot of it in university, and then catching up on it again on my own while learning about 3D graphics. (American, in high school during early 00's)

[AlexeyBrin]

The math courses from my first university year where 90% a redo of the math from my last two years of high school. The difference was that in university they emphasized the theory over exercises, basically forced us to learn 1 - 2 hours demonstrations of some theorem.