For those who are thinking about it..... I recommend it While studying machine learning, I found a linear algebra lecture and ended up taking it... I finished it today~ㅋㅋ First of all, it's fun. If you ask a question by email, they answer quickly (they really answer quickly, they're awesome~) I've taken many other domestic/international online lectures, but this is the cleanest. Please make lots and lots of probability theory, optimization, etc.!!!:)