In my opinion, MOOCs tend to underplay pre-requisites. The content in the initial classes lead to a bit of furore amongst the students on exactly the same topic. Evidently, a lot of students found the notation and mathematics (e.g. Algebra, matrices, eigenvalues, calculus) very hard to understand.
In response to this, one of the faculty - Jeff Ullman categorically stated in the forums that this course is taught to graduates in Stanford (CS 2xx is grad level) and an undergraduate course in mathematics is pre-requisite. Although most of the mathematics covered in the course is covered in a typical undergrad class, IMO the overall content is quite advanced and graduate class worthy.
That being said, the forums (and the book) are quite helpful, and given you put in enough time, you will sail through.
But the post itself says: "The book, like the course, is designed at the undergraduate computer science level with no formal prerequisites. "
Any thoughts about the discrepancy?