"Prerequisites: This not meant to be an introduction to Machine Learning course. Hopefully you've all got some knowledge to machine learning, otherwise you may find this a bit opaque. So at least you should understand/have taken courses in linear algebra, calculus, probability, ... we are not going to do anything particularly challenging in those areas, but ideas from those areas will be useful."
Those sound like standard pre-reqs for any ML course - it should probably be a standard disclaimer on every course except for intros (even there, though, you'll want the linear algebra and probability knowledge - at least the bare basics). I can only imagine the number of people who jump into such courses and get in over their head very quickly...
around 7 mins 30secs into the introduction