priority claim

May 31, 2011 in 21-point Tic-Tac-Toe, Graphics, Projective Spaces

here’s another picture of a dualization of the projective plane on the field of four elements: . in the first of two tweaks since the last version published here, i reversed the positions of the roots of x^2 + x +1… i’ve been calling ‘em alpha and beta… reversed their positions, i say, for the [...]

owen by the way

May 27, 2011 in Cool Tricks, Exercises, Notations

composition of linear fractional transformations compared to two-by-two matrix multiplications. consider in other words, let f(x) = (Ax+B)/(Cx+D) and let g(x) =(ax+b)/(cx+d) and consider the function (“f\circ g”, i.e. f-composed-with-g). recall (or trust me on this) that [f\circ g](x) = f(g(x)); i.e., functions compose right-to-left (“first do gee to ex; then plug in the answer [...]

two rungs make a rite

May 20, 2011 in Cool Tricks, Links, Math 151

logarithmic differentiation at .

bug report

May 17, 2011 in Cool Tricks, MathEdZine

the last display of MEdZ #0.4 is this wordless version of cantor‘s epoch-making result that there are “more” (in the sense of cardinality, a concept i outlined in the last post) elements in (the Real Numbers) than in (the Naturals). and a pretty picture it is, too… to at least *one* set of eyes. but [...]

MEdZ 0.4 debut

May 13, 2011 in Lectures Without Words, Math 151, MathEdZine, Real Numbers

at long last. this has been sitting on the paperpile very-nearly-finished for quite a while. i started the “lectures without words” series early on with 0.1: . whose cover more or less announced implicitly that it was one of a series called . and that was, like, five quarters ago. and they’re only 8 micro-size [...]

m’aidez

May 2, 2011 in Blogs

math stood tall: edusolidarity recap at JD’s.

competition fostering co-operation

May 1, 2011 in Life Story

yang’s Ohio ARML page at CSCC. i volunteered at a practice session yesterday. mostly logistical stuff, more or less of course. but with, anyway, a few opportunities to talk about math and life with people not inclined to dismiss me outright as soon as… or even *before*… i even open my mouth to speak. rare [...]