I was an applied mathematics major in college, and had a fairly good grounding in statistics (including related topics such as probability theory and stochastic processes). At the time the major job opportunity associated with learning statistics was being an actuary; that didn’t sound too exciting to me, so I went off and did other things. I long ago forgot almost all of the mathematics I learned, due to not having to use it in my day-to-day work.
Now in the 21st century I come to find out that with the advent of statistics is sexy. (If only I knew…) I’m not about to change careers, but I thought it might be fun (at least for my definition of fun) to refresh my skills in this area. I could take a statistics course, but I have no immediate need to run chi-square tests. (Though I am starting to learn how to use R.) My personal preference is for gaining an in-depth understanding of a subject, so I thought I’d instead start with relearning the underlying mathematics that I’d forgotten.
My chosen first task is therefore to relearn linear algebra, using as a textbook Gilbert Strang‘s out-of-print Linear Algebra and Its Applications, Third Edition, a copy of which I was able to pick up cheaply on Amazon. I’m a stickler for working through all the exercises in a textbook, and was initially doing it using pencil and paper. However after a while I got preoccupied by other things and stopped doing my math homework.
To rekindle my interest I hit upon the idea of publishing the worked-out exercises as blog posts, one per day. Besides giving me an incentive to keep working, this also allowed me to indulge another past interest in mathematics publishing using TeX and LaTeX. As a result of my previous job at the Mozilla Foundation I recently got re-interested in the general problem of displaying mathematics on the web. It’s a long-standing problem, and progress has come slowly.
In the future I may take advantage of some of these new technologies. However for now the path of least resistance is to take advantage of the LaTeX support provided by WordPress.com (where I’m hosting this blog.) Although it has its quirks it works reasonably well across browsers and it’s used by a lot of working mathematicians.
If you have any interest in the material I’m creating, please note that I’m making all of the content on this blog available under a Creative Commons license; see the sidebar for a link to the detailed license terms. If you do redistribute, reuse, or adapt the material please attribute it to me (Frank Hecker) and include a link to this blog (math.hecker.org). If you find typographical or mathematical errors in any of the exercise solutions please contact me at <firstname.lastname@example.org>.
Finally, if you find these posts useful I encourage you to also check out the more current Linear Algebra and Its Applications, Fourth Edition, Dr Strang’s introductory textbook Introduction to Linear Algebra, Fourth Edition and the accompanying free online course, and Dr Strang’s other books.