I need to make a playable version of this for the browser, but it is a fun puzzle to see how many convex polygons you can form by assembling the seven puzzle pieces here, tangram-fashion. They're drawn on a grid of 30-60-90 triangles.

I have a habit of referring to "eigenstuff" and "eigencritters" in linear algebra, and a student illustrated this.

Today I ran across the site "WikiWand" which I would describe as "a pretty-printer for Wikipedia," which is to say, it serves up wikipedia articles in an eyeball-friendly way with some reader conveniences. I kind of like it, I think - even nicer-looking than Firefox's Reader view which I like a lot. Something feels sketchy about it, though, and I'm not sure why.

jsiehler boosted

I did some creative coding the other day. I'm quite happy with the results :) 1/2

Cantor's diagonal argument for non-denumerability boils down to "Every function from the natural numbers to the reals fails to be surjective."

Is there an equally lovely but underappreciated argument that does "Every function from the real numbers to the natural numbers fails to be injective?" If not, why is that direction more difficult?

One should probably not enjoy oneself so much when writing distractors for multiple choice questions. And yet, I do.

In two classes (at very different levels) today I will be proving "Solvable by Radicals => Solvable Galois Group" and "There is no one-to-one correspondence between the natural numbers and real numbers."
Why bother coming back for the rest of the semester, I ask myself.

Which is all fine, I'm just saying I got the Babel fish out of the vending machine with less hassle.

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The process of recording a meeting in Google Meet is now:
1. Pop up menu, hit "start recording"
2. That pops up a side panel with a cool graphic and a "start recording" button.
3. Hit THAT "start recording" button then you get a dialog box which has a "start recording" button (and a reminder to check that everybody's OK with recording)
4. Hit "start recording" in the dialog box. Recording starts. Wow!
5. The side panel with the cool graphic remains in place.

when uncertain what to do, always consider the stabilizer of a point

Ah, late spring in Minnesota, when a guy can mount his bicycle in the
afternoon, ride free, and breath deep great lungfulls of fresh atrazine.

I'm too tasteful to include the heart eyes on the actual slide for class, but really, one must acknowledge the beauty of this stuff.

See what I did there, posting an artist's work without crediting them? That's bad. Don't do that like I did.

Here's the artist:

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I'll be teaching multivariable calc in the fall, which I haven't done for a few years. I taught it out of Stewart quite a few times. The faculty here in recent years have taught out of Marsden and Tromba but I don't think that's a good fit (especially since our department doesn't have linear algebra as a prereq for multivar). I don't love the cost of Stewart, either, though. Anybody got any textbook recommendations?

"how'd ya like that there stravinsky or whatever?"
"oh, it's different"
- overhead, Paris, 1913

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