I’m a sophomore in US college majoring in mathematics. I plan to apply for math PhD. I’m wondering how bad does the major GPA need to be for giving explanation? For example, do we need to provide explanations for a single A- out of straight-A’s?
Also, factors to take into account also include core courses (real analysis, abstract algebra, topology, etc.) vs. electives (combinatorics, number theory, probability, etc.), other courses taking along together e.g. 2 major classes in a semester vs. 4 major classes in a semester.