Fall 2020 - After reading all those "great" reviews for this professor, I thought its a good choice to take Math 170S as one of my elective class, but I can't describe how awful this class was. Imagine someone just reads you the lecture note pdf that is already uploaded, word by word in slow motion and leaving the questions unsolved, then having a quiz every other week which takes so much time with only 2hr limit time. (Btw if you f*ckup your midterm, quizzes will worth 50% of your grade so really be careful on quizzes). Finally both midterm and final was the worst and impossible to pass since the instructor will be grading it himself with absolutely no partials. My advise: This class is far away from being easy and useful, so don't waste your time on taking Math 170S with LYU and try whole quarter to pass the class, either take someone else or ovoid probability and stats.
Winter 2020 - The class is fine, but far from good. Hanbaek is a decent professor, who is nice and chill. However, he arrives at class six minutes late on average, and don’t care about that at all. His lecture notes are good, but with some minor notation confusion, so there is no need to attend every class (he basically copies his lecture notes in class). Tests are fair, but the final is too easy as a take home final (class average is around 91%).