> I got a B in Linear Algebra, and I still can't describe why you'd need that in the real world, while calculus/diff eq/discrete math were clearly tied to physi

> I got a B in Linear Algebra, and I still can't describe why you'd need that in the real world, while calculus/diff eq/discrete math were clearly tied to physics/thermodynamcis/computer science problems I knew. I thought this was an interesting comment, because I personally believe linear algebra is one of the most applicable topics in math and relates a lot to the topics you contrasted it with. For example, in multivariable calculus, derivatives of functions with multiple variables end up being linear maps, and understanding properties of those maps and how they're transformed helps a lot with understanding the properties of derivatives and how to apply them. Differential equations are solved in practice by approximating them as linear systems and solving those equations, so again, understanding linear algebra helps a lot there (e.g., eigenvalues are intimately connected to the ways differential equations behave). I'm not so familiar with discrete math, but I do know there are connections between linear algebra and some areas of graph theory (not sure how critical they are to those areas, though). That's not meant as a criticism of your comment, because I think the way linear algebra courses are taught doesn't do much to make those connections clear. Intro courses focus a lot on mechanical problem solving and do a poor job of motivating concepts (e.g., I remember eigenvalue problems showing up mostly out of nowhere). In courses beyond the introductory level the presentation and focus is more abstract and does little to demonstrate why you would care beyond intrinsic interest. I think if more motivation or context were provided, it would help encourage those more interested in applications than math for math's sake to go deeper into a topic that can be very useful in a lot of applied areas.