#conics — Public Fediverse posts

Abū Sahl al-Kūhī (or al-Qūhī; fl. c.970–c.1000), who was regarded by contemporaries as the ‘Master of his age in the art of geometry’, once wrote of his motivation for considering a problem:

‘Having completed the construction of a regular heptagon in a circle, we set out to investigate another proposition, one more beautiful [ʾaḥsan أحسن], deeper, more opaque and more difficult to find out than the construction of the heptagon […]. This is the construction of an equilateral pentagon in a known square.’

Al-Kūhī's construction is shown in the attached diagrams. The red and blue curves are hyperbolae, both with latus rectum equal to 2AG, and with major axes NS and PI. The segments AE and DK (found using the the intersection of the hyperbolae) are equal to the required sides of the pentagon and a simple translation moves them into position.

(Note that the pentagon is only *equilateral*, not *equiangular*, and so is not regular.)

#MathematicalBeauty #geometry #HistMath #conics

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#scribesandmakers Shames someone-else-promotion day. No one said I couldn’t do two 😉

Shoutout to @AudraBalionArt

She’s a phenomenal artist, and I don’t say this just because I am legally bound to (it was part of the marriage license).

She’s had guest spots at conventions across the prairies, has taught comics and character design at multiple schools, and completed a very ambitious project: a graphic novel without words!

https://audra.balion.ca/graphic-novel/

#conics #artist #art #canada

@bodhidave @EgyptianAphorist @mcmullin @clarablackink @histodons
Mathematics and #art are human activities, and in a #mathematics paper
(on #conic sections, the #conics, in particular, and described in the
linked blog post), I was pleased to have reason to quote what
Robert Pirsig said about teaching #writing. I commented,

> What #Pirsig wanted, as an English teacher, was for students to learn
> to write what *they* wanted. In the end, this would be what everybody
> else wanted, which was *quality.*

But there's a difference:

> In mathematics, an essential part of #quality is *truth,* or
> *correctness* if you prefer. We take this to be universal.

Not everybody may agree on what is good art, but I think they should
agree on what is correct mathematics.

https://polytropy.com/2020/08/05/an-exercise-in-analytic-geometry/

Five years ago, I wrote about this issue of Justice League of America: https://tombrevoort.com/2018/01/20/another-subscription-copy-of-the-giant-justice/ #conics #dc #dccomics #justiceleagueofamerica #steveenglehart #dickdillin

Conics intersecting the sides of a triangle: http://geometriadominicana.blogspot.com/2019/?m=1

#math #geometry #conics

Giving Moses a bath. #conics #religion #humor.

At long last, OUTRAGE is available in print and ready to give you a paper cut! https://www.simonandschuster.com/books/Outrage-Volume-1/Fabian-Nicieza/9781952126574
Pick it up at your favorite comic or book store, or order it online from the link above!
.
#outrage #conics #fabiannicieza #reillybrown #rocketshipentertainment https://instagr.am/p/ClloorEL_4O/