Hi all. I'm an international student and I obtained my B.S in Statistics degree outside the U.S. In my country, calculus is offered for two classes; one semester for single variable and another for multivariable calculus. In my department, we had a one semester calculus course for stat major which covers single variable calculus and basic multivariable differentiation and integral mainly for probability theory. I took Analysis I and got A+ in this course. I have taken calculus for stat major / Linear Algebra I, II / Analysis I and thought this would be enough for Ph.D application.
However, I am attending a small university in the U.S pursuing a master's degree and my advisor asked me why I have not taken any calculus class yet. I explained him that I took one semester calculus but it seemed like it confused him a little bit. (I've heard that for some big state universities where they have a lot of international students, the professors are more aware of that some countries only offer calculus throughout two semesters). I have never had any issue studying probability with my calculus knowledge, in fact, I aced in a probability course. However, when I looked at the syllabus for multivariate calculus, I noticed that the course actually covers a lot more than I studied from my undergraduate (such as Lagrange Multipliers and Gradient Vectors)
In this case, do I need to take multivariate calculus? If I need to take this course, I would like to audit instead of getting credits, but is this a good idea? because I won't have multivariate calculus on my transcript. In addition, I am planning to take graduate-level real analysis as well. I've sometimes heard that taking advanced classes might compensate undergraduate level courses. I am also planning to apply for a few stat Ph.D programs and mostly biostat Ph.D programs. Any advice will be very appreciated!