this post was submitted on 01 Feb 2024
194 points (100.0% liked)

196

18100 readers
521 users here now

Be sure to follow the rule before you head out.


Rule: You must post before you leave.



Other rules

Behavior rules:

Posting rules:

NSFW: NSFW content is permitted but it must be tagged and have content warnings. Anything that doesn't adhere to this will be removed. Content warnings should be added like: [penis], [explicit description of sex]. Non-sexualized breasts of any gender are not considered inappropriate and therefore do not need to be blurred/tagged.

If you have any questions, feel free to contact us on our matrix channel or email.

Other 196's:

founded 2 years ago
MODERATORS
 
all 19 comments
sorted by: hot top controversial new old
[–] OccamsTeapot@lemmy.world 76 points 2 years ago (1 children)

Mathematicians write the most insane shit you've ever seen in your life then they're just like □ peace out

[–] bonus_crab@lemmy.world 12 points 2 years ago (1 children)

If you wrote the equivalent of this in software I think linus torvalds himself would personally show up to destroy your pc.

[–] Aqarius@lemmy.world 4 points 2 years ago

Nah, formulas like that are basically the assembly code for logic.

[–] slampisko@lemmy.world 42 points 2 years ago

statements dreamed up by the utterly deranged

[–] Sasha@lemmy.blahaj.zone 25 points 2 years ago (1 children)

OP, I need the definition for × and <,> too

[–] affiliate@lemmy.world 24 points 2 years ago (2 children)

× is the cartesian product and = {x, {x,y}} is the ordered pair of x and y. (i.e., if x is in X and y is in Y, then is the corresponding element of the cartesian product X × Y). hope this helps

[–] rasensprenger@feddit.de 9 points 2 years ago (1 children)

What does type() mean here?

[–] affiliate@lemmy.world 22 points 2 years ago (2 children)

it's the "order type" of a well ordering on a set. so, given a set X with a total ordering R, type(X,R) is the unique ordinal isomorphic to (X,R)

[–] bort@feddit.de 11 points 2 years ago (1 children)

what's with the square at the end? isn't that usually for proofs?

[–] affiliate@lemmy.world 13 points 2 years ago

yeah but sometimes when the textbook authors are feeling particularly mischievous they'll just put them in random places. and sometimes they'll even skip the proofs but keep the square.

[–] Lemjukes@lemm.ee 7 points 2 years ago

Give it up for op actually out here answering questions like a real live teacher.

[–] Sasha@lemmy.blahaj.zone 2 points 2 years ago

Oh wow, I should know that... Thanks

[–] Pretzilla@lemmy.world 15 points 2 years ago
[–] hips_and_nips@lemmy.world 14 points 2 years ago (1 children)

This is giving me PTSD flashbacks from Number Theory at uni. What a fascinating mindfuck.

[–] affiliate@lemmy.world 7 points 2 years ago

oh god number theory.... the things they make you do in that class.......

[–] yetAnotherUser@feddit.de 10 points 2 years ago (1 children)
[–] riodoro1@lemmy.world 3 points 2 years ago

Im sorry, but the capital form alone justifies its existence.

[–] Ragdoll_X@lemmy.world 5 points 2 years ago (1 children)

Is this from Principia Mathematica or smth?