I searched and all I could find is recommended texts. I was just wondering was areas of mathematics should I know before cracking open a book on QM. I know they give you pre-requisites and that can give some hints, but sometimes that isn't enough. I'm sure some students experience the I-wish-I-took-calculus-before-PHYS101. In other words, what should I know, and what do you wish you knew before going into QM. Thanks.