Reading the Comics, November 21, 2012

It’s been long enough since my last roundup of mathematics-themed comics to host a new one. I’m also getting stirred to try tracking how many of these turn up per day, because they certainly feel like they run in a feast-or-famine pattern. There’d be no point to it, besides satisfying my vague feelings that everything can be tracked, but there’s data laying there all ready to be measured, isn’t there?

Todd Clark’s Lola (November 12), about a cranky old woman who somehow isn’t the cranky old woman from the Hallmark cards a couple years back, mentions fractions in the weakest form of the joke.

Steve Breen and Mike Thompson’s Grand Avenue (November 13) does that joke you’ve seen passed around about silly algebra exam questions, although not in the short punchy version that you get by entering “find x” in a Google image search.

Chip Sansom’s The Born Loser (October 14) contains what seems to me an unusual appearance of the term “mathlete” without its referring specifically to people competing in mathematics events. This is maybe one more for the etymological comics pages, but I don’t know where those are.

Lincoln Pierce’s Big Nate (November 15) tosses off a silly definition of an isosceles triangle as part of establishing that a substitute teacher is being silly or isn’t up to substituting mathematics. I don’t envy substitute teachers, particularly mathematics substitutes. Mathematics is a subject it feels like students are very skeptical about learning, and it takes time to build the trust with them that this is interesting and rewarding, and substitute teachers don’t have much of that; add in the lack of time to gauge students’ background and familiarity and I’m fairly certain I’d make a hash of filling in for someone else’s class. But I’d get the definition of the isosceles triangle right, if needed. (An isosceles triangle is one with two sides of equal length, or two angles of equal measure, whichever you like; it’s also a good spelling bee word.)

Scott Hilburn’s The Argyle Sweater (November 17) just uses an old bit of wordplay.

Jonathan Lemon’s Rabbits Against Magic (November 17) features Möbius strips, as tires that will “last forever”. I have heard it alleged that Möbius strip-designed belts are sometimes used, as ways to easily double the lifespan of the belt, which seems superficially plausible, although lasting forever is obviously someone’s little joke. (Möbius strips are also a subject of far too many science fiction stories that try to do a math gimmick; I recall one collection of mathematics science fiction — I want to say edited by Clifton Fadiman — that got agonizing in the repetitiveness of the theme.)

Mac and Bill King’s Magic in a MInute (November 18) shows off a mental-mathematics trick, if you do want to call it that. Just why this trick works is none too hard to figure out, at least if you’re comfortable working out symbolically just what’s being calculated and if you’re comfortable with the commutative law.

Richard Thompson’s Cul De Sac (November 19, Rerun) poses the question: what is the difference between a rhomboid and a parallelogram? Petey and Alice’s father attempts to offer an answer, but Alice offers the better question, and I suspect that the challenge of memorizing all the terms of these different geometric figures are going to flounder, at least somewhat, unless it’s made clear why it’s worth having separate names for parallelograms and rhombuses.

(A parallelogram is a figure with four sides, in which two pairs of the sides are parallel. A rhomboid is a parallelogram in which all four sides are the same length. A rectangle is a parallelogram in which the sides that aren’t parallel are perpendicular; meanwhile, a square is a rhomboid where the sides which aren’t parallel are perpendicular. And yes, just as a square is also a special sort of rectangle, so is a rhomboid a special sort of parallelogram, and a square is also a special sort of rhomboid. All these terms and cases where one shape is a kind of other shape does make it sound less like we’re doing geometry than we are collecting and classifying leaves, but if we have to work with a lot of shapes it’s convenient to have names for the interesting or attractive ones.)

Garry Trudeau’s Doonesbury started on November 19 and ran through the 24th a “Math and Science Victory Lap” attempting to celebrate the triumph of “simple arithmetic” in the recent United States Presidential election. The strip of the 20th uses the 100 percent joke I’ve defended before; the others go into various other fields of science that the election supposedly showed the populace favors. (I’m skeptical that the election results represented the electorate’s opinion on any math or science issues.)

Eric the Circle (November 20) finally got around to one of those trigonometry jokes I would’ve figured would be more its bread and butter. A secant is a line that just cuts directly from one point on the circle to another, not necessarily going through the exact center of the circle. The word, I understand, comes from the Latin “secare”, meaning “cut”, which might help clarify which of the many lines you can attach to circles that it is. (The tangent, which just touches the edge of the circle and never goes inside it, has a name derived from “tangere”, meaning “touch”.) If the secant doesn’t go very far along the arc of the circle, than its length is a pretty good approximation of the curve of the circle between two points, in much the same way if you aren’t going too far over the surface of the Earth a flat map is a pretty good approximation to the sphere of the planet.

This has great consequences: straight lines are much easier to work with than curved ones are, so, if you can approximate the tricky curve you want to deal with by a secant line, you’ve probably made your work easier without making too big an error. Of course, if you do have to work over a long curve the secant won’t be very good anymore, but, it might be worth it to use two secant lines, or three, or even a huge number, rather than deal with the curve. This is why secants (and tangents) are useful things.

Grant Snider’s Incidental Comics (November 21) builds on the comparisons between pi and pie, and builds this to wonderful detail, as Snider always does. Snider is able to bring in pie charts, Venn diagrams, area of angular slices, probability, and volume; so, this is not only a pleasure to look at but also something that might help you learn a couple of formulas.

There’ve been more mathematics strips since then, but a little pause in the comics after that run, and the number that had accumulated, make me want to break here. There’s already six math-touching comics from after Thanksgiving which I’ll get to in time, I trust.