Mathematics as one of the core subjects
Mathematics for at least two years/four semesters
Mathematics/ Statistics as a subject for at least two years/four semesters.
Any one of Biology, Biotechnology, Chemistry, Mathematics and Physics for two years/four semesters, and any one of the other four subjects for at least one year/two semesters.
Mathematics and Physics and any one of these subjects among Chemistry, Computer Science, Computer Application, Geology and Statistics
If you want to know more details about IIT JAM Mathematics then go to the above link.