The applied side of approximation theory is like black magic to me: even if I don’t want to do research in the area, at least I respect it enough to find it interesting. So, I recommend bit-player’s post on Nick Trefethen’s Chebfun package. Especially check out the links (Trefethen’s an engaging author).
Asides
ChapterZero’s relocated
I still haven’t hammered out the database issues, but I’m tired of my little vacation (i.e. several months!) from posting, so I’m going ahead with the relocation. At some unspecified time in the future (once I figure out the technical details), I’ll migrate the database over from the old location. That site’ll still be up, albeit in its broken state (the math and other escaped code is not being interpreted correctly).
Here’s an inagural problem: Argue that \[\frac{21}{22} \geq \frac{\log 9}{\log 10} \geq \frac{20}{21}\] without using decimal expansions of the involved quantities. Feel free to use arguments that aren’t feasible without a CAS like Mathematica– I sure did.