I'm currently a 2nd year Physics undergrad who is contemplating adding a math minor. My plans for what to do after undergrad will most likely involve a Masters in some engineering branch (contemplating Mechanical Eng.) or grad school for physics (not so certain if I love the stuff enough to spend that many more years on it). The Math minor at my school simply requires 5 math upper-div courses. The ones I have in mind are Linear Algebra, Complex Analysis, Applied Numerical Methods, PDEs, and some elective to be determined. My other option would involve not declaring the minor and taking only Linear Algebra, Complex Analysis, or whatever other upper-div math courses I want (<5 total), and petitioning my way into 2 engineering courses to possibly get a feel for what's involved in engineering. Most of my friends within my dept.(Physics & Astro) have suggested that I forego the math minor completely and simply concentrate on research instead. The reasoning they used was that I should not get the minor if I'm planning on using it as some sort of "plus" for my grad school app, since most students end up double-majoring in Physics and Math anyway, so simply minoring in it would pale in comparison. This has been suggested to me despite whatever academic/career path I'm looking at, whether it involves me planning on pursuing a job immediately after undergrad or if I'm looking at a PhD. If I decide to do this, I may end up trying to self-study with some of the Dover math books for whenever I need to cover something.