Praise then darkness, and creation unfinished

Misc. comments 66

2024-05-02T13:11:09Z

Misc. comments 66: ( terminology, the river Thames, recipes and ingredients, family trees, classifying fruit, covid precautions, learning math, subscription prices, reasons for blogging )
( covid vaccination and masking )

minoanmiss was talking about kids at the place she works trying to get out of math class. amaebi talked about her son's math classes, and I wrote:

Reading this comment, I think part of why I came out of high school still liking math may be the teachers, and another part may be the slightly odd curriculum they were using. It was the "experimental" math track per my high school, and "unified" according to the university that promoted it; we got a lot of the standard material, up to calculus, but also propositional logic (in eighth grade), Cartesian geometry (instead of Euclidean), and combinatorics. The school also had a "regular" math sequence, and students who found experimental too difficult (or, I would guess, whose parents thought it was too weird) could move into those classes, which also led to calculus).

In response to brithistorian wondering about weird magazine prescription costs:

My guess, beyond late stage capitalism being weird, is that they're somehow still selling advertising to companies based on the number of people who are reading, or at least getting, the print edition.

If so, it benefits them to be sending out more paper copies, even to people who read the digital version and will throw the paper magazines away without opening them. It sounds like the prices of daily newspapers increased when they were selling fewer ads. What I paid at the newsstand in the morning was about enough to cover the paper and printing costs, and the reporters' and editors' salaries, the fees for syndicated comics and columnists, and any profits all were paid for by advertising.

It's not quite "if you aren't the customer, you're the product," but it's a little bit in that direction. At one point, my daily English-language newspaper options in New York included several that cost about 50 cents, plus two free papers given out at subway and railroad station entrances, and the Wall Street Journal and Women's Wear Daily.

finch was talking about "why do I blog anyway?" and I said:

Part of why I post here is for my own later reference, which includes both things I hope will be interesting to others, and minutiae of stuff like starting on new meds. I made a bunch of posts early in the pandemic because I could feel time just slipping away, then.

My posts here are also about talking to people, which is sometimes conversation and sometimes "here is information I think you might find useful.".

There's a pinned post at the top of my Dreamwidth account page, which says this is [partly] an online substitute for a paper journal, and also invites new readers to introduce themselves.

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fun with numbers

2023-01-01T20:10:23Z

Happy Fibonacci Day! 1/1/23

As carbonel pointed out, this works in both the American month/day format and the European day/month format.

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Nicely abstract

2016-07-20T18:13:45Z

I turned in the copyediting job, and am now back to proofreading a math book. Here at the bottom of page 16, I find "By the axiom of choice, there exists a set B which consists of one element from each Aα."

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Not that you need this advice

2012-04-25T14:31:22Z

"If you ever find yourself raising log(anything)^e or taking the pi-th root of anything, set down the marker and back away from the whiteboard; something has gone horribly wrong." —Randall Munroeq

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redbird @ 2010-06-28T20:52:00

2010-06-29T00:53:32Z

I'm not sure why I'm so pleased by today's xkcd, but I am. (cattitude says the mouseover text is what makes it, but I was smiling before I got to that)

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Misc. comments 46

2010-01-10T03:03:44Z

More saved comments: ( poetry and structure, comfort food, warnings for disturbing content, the distinctions languages make, reading and rereading, 'guilty' pleasures )

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The missing word was "three"

2009-06-06T00:11:57Z

A bit of googling this morning made sense of yesterday's mystery: the key word was "three," and the sentence needs rearranging. What they're trying to say, I think, is "when three lines meet at a point, they are called concurrent." Which is not a neologism, but doesn't match the other meanings of "concurrent," which were used in several previous lessons, so I hope the editor will make that (or some similar) change, so the students will see "this is an additional meaning of the word" rather than wondering what it means to say lines are the same length (that being what "concurrent" means for line segments).

This is a lead-in to stuff about triangles and the intersections of their angle bisectors, etc., which lurk under names like "incenter" and "orthocenter" and "circumcenter" (the circumcenter of a triangle is not always within the triangle). I suspect that the bit about concurrent lines could be deleted without any loss to understanding, but I'm not editing this book.

Someone asked, in response to yesterday's post, what I like about working on the algebra books, and why they bother issuing new geometry books, because aren't they all more-or-less literal translations of Euclid's Elements, since there's nothing new in geometry.

The short answer to the first includes that I like helping get things right, and that in some moods I enjoy things like factoring quadratics and getting paid for it. For the second, there are several answers, including "there's quite a bit new in geometry, and a little bit of it even turns up at the high school level." However, while I like tesselations, they don't lead much of anywhere, and I'm not convinced the addition of the "kite" to the list of standard quadrilaterals is an improvement. Trigonometry, which is a significant part of high school math and at least some of which is in geometry, is not in Euclid. Non-Euclidean geometry, which is also not in Euclid, is well beyond the scope of what we're being asked to cover, even though our world is not in fact a plane. Other answers (in addition to "because people want to buy the books," which is non-trivial: if nobody would buy them, we wouldn't bother producing them) include that different books emphasize different subsets of mathematics, and that even if the ideas or results are the same, there may be different good ways of teaching them, in different contexts and for different learners.

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I would rather be doing algebra....

2009-06-04T23:34:42Z

than geometry: but you can't always get what you want.

Cold-reading a geometry book is useful. Doing the same for an algebra book is that, and sometimes also fun.

Also: I left today after getting to a lesson whose beginning falls into "This isn't right. This isn't even wrong." A sentence in a high-school math review/test prep book that begins "If lines are congruent," has nowhere useful to go. I'm hoping that in the morning I will be able to get some idea of what the writer actually meant to say and/or what the editor thought was there, which may mean guessing at the line that the compositor dropped. If not, it gets flagged as "Rosemary, this doesn't make any sense. What's in the manuscript?"

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