Alan J. CainFeb 9

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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Show threadEmpyClawSep 23

#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

Flight Nineteen | Graphic Novel & Comic

Ten years in the making, Flight Nineteen is Audra Balion's premier graphic novel. A story told in silence, this comic pushes the boundaries.

Audra Balion
Your Autistic Life FR/EN/ESSep 15

"Hi."

"Hello. What are you exactly?"

"I'm a conic section."

"But... you look like a line! OMG! You're a degenerate, aren't you?"

#conics #ConicSection #math #degenerate

Your Autistic Life FR/EN/ESSep 12

Hooked on Conics, the new program for teaching conics to kids!

#conics #math

∞ 𝕁uan ℂarlosNov 13, 2024
📣 🎥 All types of conics, all at once!
https://youtu.be/Yn6dWxw787w
#mathematics #conics #envelope #geometry
Construction of all conics as envelopes of straight lines

YouTube
∞ 𝕁uan ℂarlosAug 23, 2024

Rainbow conics as envelopes of straight lines

https://www.geogebra.org/m/gqkwtn7p

#mathart #geometry #conics

Rainbow conics as envelopes of straight lines

Rainbow conics as envelopes of conic straight lines

GeoGebra
Fabiano Cerqueira 🖖Feb 25, 2024

Tarzan #54 (Ebal, Mar. 1970)
"Tarzan e a Cidade de Ouro" (Tarzan and the City of Gold)
Tarzan's imprisoned in Cathne (City of Gold) by Queen Nemone and must fight for his life in the arena.

Tarzan #55 (Apr. 1970)
"Os leões de Cathne" (The Lions of Cathne)
Cont. from last issue. Tarzan continues to fight for his life. Nemone, maddened by jealousy, meets a tragic end.

E.R.B. novel adaptation. Gaylord Du Bois (text), Doug Wildey (art), George Wilson (cover)

#BrazilianComics #ComicBooks #conics

Comic CrusadersNov 8, 2023
THE HIT MIDDLE GRADE FANTASY “GOBLIN” RETURNS WITH “GOBLIN: THE WOLF AND THE WELL”
What would you give up to protect the one you love? This question is explored in the upcoming sequel to Eric Grissom and Will Perkins’ successful fantasy tale, Goblin. The new graphic novel, Goblin: The Wolf and the Well, is written by Grissom and illustrated by Perkins....
https://www.comiccrusaders.com/the-hit-middle-grade-fantasy-goblin-returns-with-goblin-the-wolf-and-the-well/
#conics #Dark Horse Comics
THE HIT MIDDLE GRADE FANTASY “GOBLIN” RETURNS WITH “GOBLIN: THE WOLF AND THE WELL”

What would you give up to protect the one you love? This question is explored

COMIC CRUSADERS, LLC
Show threadDavid PierceApr 30, 2023

@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/

An Exercise in Analytic Geometry

Polytropy
Prof. Sally KeelyMar 3, 2023
Fun read. "Lane formation doesn't require conscious thought—the participants of the experiment were not aware that they had arranged themselves into well-defined mathematical curves." and "At a glance, a crowd of pedestrians attempting to pass through two gates might seem disorderly but when you look more closely, you see the hidden structure. Depending on the layout of the space, you may observe either the classic straight lanes or more complex curved patterns such as ellipses, parabolas, and hyperbolas." #curves #conics https://phys.org/news/2023-03-lane-hidden-chaotic-crowds.html
Stick to your lane: Hidden order in chaotic crowds

Have you ever wondered how pedestrians 'know' to fall into lanes when they are moving through a crowd, without the matter being discussed or even given conscious thought?

Phys.org