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Watch my set please by Basil Fussletut - Fri, 18 Nov 2016 11:24:03 EST ID:FFd5rNZG No.15275 Ignore Report Reply Quick Reply
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Hey /math/, can you guys watch my set for me? I'll be right back.
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Polly Crazzlestodge - Thu, 12 Jan 2017 13:12:19 EST ID:zauFrAWR No.15321 Ignore Report Quick Reply

You don't absolutely have to use category theory or type theory to talk about that kind of collection. There are extensions of ZFC in which you can discuss proper classes like the collection of all objects that don't contain themselves, like Neumann-Bernays-Godel set theory. In New Foundations set theory there is powerful comprehension so the collection of all sets is indeed a set. It dodges Russel's paradox by specifying what kind of predicates are allowed to define sets.
Ebenezer Genkinnadge - Thu, 12 Jan 2017 14:29:49 EST ID:jD/Lrc1O No.15322 Ignore Report Quick Reply
Both of those systems you mention seem to be exploiting the idea of different "levels" of sets, which sounds like a type-theoretic way of dealing with the problem to me.
Augustus Bambleson - Thu, 12 Jan 2017 19:13:32 EST ID:zauFrAWR No.15323 Ignore Report Quick Reply

Yeah, there are different "types" of objects, but often times it's not apparent what a given object is. From this perspective you could make an argument that every set theory is a type theory, with just one type in consideration, which seems to obfuscate what distinguishes what is considered type theory as opposed to something else. In type theory you know exactly what sort of element you are dealing with, while this might not be the case in set theory.
Caroline Burringfoot - Thu, 23 Mar 2017 03:22:14 EST ID:zYLZ69Gw No.15432 Ignore Report Quick Reply
no, fuck sets
Thomas Derringbock - Thu, 23 Mar 2017 10:27:39 EST ID:2BTsxPZ9 No.15433 Ignore Report Quick Reply
What do you advocate instead of sets? Topoi or some new-fangled nonsense?

Best language for math by Simon Sattingbury - Wed, 22 Mar 2017 03:37:13 EST ID:lwS34rUW No.15429 Ignore Report Reply Quick Reply
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George Brablingfoot - Wed, 22 Mar 2017 22:10:52 EST ID:j58znr37 No.15431 Ignore Report Quick Reply
All I know is that when the Chinese talk math about every other word is in English. Just accept American hegemony already.

Measuring turds by Jarvis Smallford - Tue, 21 Mar 2017 20:36:07 EST ID:Yl5i51yi No.15427 Ignore Report Reply Quick Reply
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Ever wanted to be able to find the volume of your weirdly-shaped poops through a mathematical model? Try Calculus! Thanks, Newton and Leibniz!
Basil Gunningfutch - Tue, 21 Mar 2017 22:28:39 EST ID:2BTsxPZ9 No.15428 Ignore Report Quick Reply
No love for Archimedes in here I suppose.
Molly Poffingbury - Wed, 22 Mar 2017 19:55:35 EST ID:LCy6AKHb No.15430 Ignore Report Quick Reply

Do not disturb my circles.

Dabble by Hugh Wicklelatch - Tue, 21 Mar 2017 08:41:37 EST ID:6dRMI9a4 No.15425 Ignore Report Reply Quick Reply
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I have hardly a basis for math and forgot most of it anyway.
I'd like to get my math level a bit up, it seems like fun now

How do i start?
Fanny Dommlestock - Tue, 21 Mar 2017 09:13:09 EST ID:1If8Lhdp No.15426 Ignore Report Quick Reply
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Get a textbook, read it, and do the exercises. You can also do online courses. Even though it's not arithmetic I would recommend doing a basic logic textbook since it's fun and important for mathematical reasoning. Math is some kind of meta-language, so you will advance faster if you have people you can talk to about it. In person is probably better than online, but even that is great. You can check out mathexchange or just post whatever you're thinking about on here.

What's your power level? by William Drenkingold - Thu, 01 Dec 2016 01:21:19 EST ID:I4oaqfW8 No.15281 Ignore Report Reply Quick Reply
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I'm new to this site and it struck me as pleasantly surprising that there's a whole set of science&math boards. I am however rather skeptical about the average level of education here, so let's make a little survery:

  1. Age
  2. Degree
  3. Specialty
  4. Dream job/profession
  5. Plans for the near future and long term strategy
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Edward Gollerstetch - Sun, 26 Feb 2017 13:51:27 EST ID:KcxMkgeE No.15411 Ignore Report Quick Reply
  1. 20
  2. Computer Engineering
  3. Well I'm also going for a maths minor so I guess maths for now. I'm starting to like Electromagnetics though
  4. Maybe embedded stuff, I haven't thought about it a lot yet but it seems to be an ok mix of hardware and software
  5. Well currently I'm trying to graduate on time so they don't take any scholarships away. Being late would complicate things a lot as I don't have any money with which to finish whatever classes I might have left with. Long term I'm still not sure. Maybe I'll go for doctorate in Germany eventually and stay there afterwards. Though that would be painful as I still have a lot of friends and day one niggas here
Barnaby Worthingham - Mon, 27 Feb 2017 21:41:36 EST ID:MnYRJPQ7 No.15413 Ignore Report Quick Reply
If "here" is the United States then you should definitely get your PhD there. It is much easier to get a job in Germany with a US degree than it is to do anything with a German degree. I don't know why exactly this is, but there are different levels of prestige.
Albert Chummlefuck - Fri, 03 Mar 2017 03:24:08 EST ID:hYgvutyX No.15414 Ignore Report Quick Reply
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  1. 27
  2. Bachelor in maths and a Master in CS.
  3. Computation (automata and language theory)
  4. Draftsman
  5. Learning korean or chinese and going ot study a phd in Korea or China.
Ernest Dankinwill - Sun, 19 Mar 2017 10:34:36 EST ID:6/N17cz8 No.15423 Ignore Report Quick Reply

How I'll afford it here in the US is a pretty important question. I realize there are scholarships and all but I gotta figure all of it out. Also if reputation is important can I not simply wave around a US Bachelor's degree in Germany if for some reason they don't like German degrees?
John Drarrypon - Sun, 19 Mar 2017 15:09:40 EST ID:c0vo/Lfo No.15424 Ignore Report Quick Reply
You shouldn't be paying for graduate school in anything technical. They should be paying you to teach and covering your tuition.

how i relearned erry mathsz by Lydia Lightshit - Fri, 05 Feb 2016 02:37:19 EST ID:mVsq12K/ No.15040 Ignore Report Reply Quick Reply
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Everyday before work, I woke up 2 hours early and forced myself to read/do exercises of the following books. (this later became 3 hours). I averaged 3 books per month if they were survey books, and about 1-3 months for a rigorous book. This became an easy routine after the first week, and I'm still doing this.

>1) Daily Rituals by Mason Currey
This is where I got the idea of making a routine from, it's a survey of historical artists, philosophers, scientists ect who all had a routine in order to get work done consistently. Franz Kafka would split his sleep up into 2 section in order to fit in work beside his regular office job.

>2) Basic College Mathematics by M. Lial et all
As mentioned before in here this covers elementary school and Jr. High math basically. You can just survey this for the most part (not do any exercises) unless you don't understand something, then do the exercises. Took 3 days to survey this. When I later took Harvard's CS50 computer science course, the first lecture about Binary numbers directly was related to this book's first chapter on whole numbers. I torrented this book.

>3)Basic Mathematics by Serge Lang
I got out the notepaper and did most of the exercises by hand. This was all focused on reasoning, why is this true, how do we prove this is true, ect. This book teaches you so well that applied calculus is your bitch afterwards. I torrented this book too since author dead, copies are like $80 on amazon.

>4)Introduction to Mathematical Reasoning by Eccles
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George Honningham - Sat, 14 Jan 2017 20:50:27 EST ID:pPw7QUKx No.15324 Ignore Report Quick Reply
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>3 books per month
How do you do that? I've been reading A book of set theory by Charles C. Pinter for about six months and have only read the first 70 pages. Some of the excerces took me days to solve them, and after two months i could finally understand the resolution of the Russell's paradox. However, I've reading it over and over again until being pretty sure my proofs of every single problem are indeed proofs.
Frederick Wicklesadging - Wed, 18 Jan 2017 12:25:37 EST ID:bkgMqk62 No.15326 Ignore Report Quick Reply

That's a slow pace, but good. I think if you are reading three math books in a month you are missing a lot of details. It took me a year to read Shoenield's mathematical logic and I have been reading Kunen's set theory for a year nearly and I'm only half way through. Shit takes time.
Emma Drundlestock - Mon, 06 Feb 2017 13:38:21 EST ID:0v0QG0m/ No.15330 Ignore Report Quick Reply
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>That's a slow pace,
Yes, I know it. That's because I got my bachelor degree in maths but never studied it seriously until now, that I have noticed my lack of foundations; and it's because of that that I don't go on unless I'm pretty sure I have solved and understood every single part of the text and the problems, specially set theory and logic, wich are basic for all mathematics. Solving all the doubts arising when studying mathematics is a very important part of our study routine if one really wants to understand them... and it's probably the most tedious part.

>Shoenield's mathematical logic
I'd swear it was a model theory book. I remember I didn't buy it due to that, and bought Richard E. Hodel's An Introduction to Mathematical Logic instead.
Jarvis Pessledale - Tue, 14 Mar 2017 17:19:17 EST ID:ueMHQ1BO No.15419 Ignore Report Quick Reply
sick, now read a Math physics textbook and become a god
George Blatherbanks - Sat, 18 Mar 2017 16:35:05 EST ID:ck7N7PYR No.15422 Ignore Report Quick Reply
Frankel's The Geometry of Physics: A very good way to learn what modern geometry tastes like.

Maths is cool n shit by Straid Of Coolaphis - Fri, 28 Oct 2016 20:21:44 EST ID:g2pPf6fA No.15254 Ignore Report Reply Quick Reply
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Can we have a maths party thread moderators? Because maths is cool and shit.
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Fuck Tillingway - Tue, 21 Feb 2017 11:32:41 EST ID:j58znr37 No.15342 Ignore Report Quick Reply
Are you trying to start shit m8?

Category theory is the new set theory, it's fucking foundational.
Phyllis Fuvingbury - Tue, 07 Mar 2017 00:21:23 EST ID:vrOFV9fT No.15415 Ignore Report Quick Reply

Nobody cares about the Yoneda Lemma and it's NONSENSE to think that a monomorphism might not be injective!!! Trash category theory go home!!!!
Archie Cenderhood - Tue, 07 Mar 2017 10:03:55 EST ID:+wJbtIkG No.15416 Ignore Report Quick Reply
Have fun remembering fifteen different definitions of some uiversal construction which are all actually the same thing in different categories. Do you enjoy clogging your brain with extraneous nomenclature? (Please, no jokes that this is all that math is.)
Priscilla Brellydale - Tue, 14 Mar 2017 16:56:33 EST ID:0IIhzQOQ No.15417 Ignore Report Quick Reply
So what do you guys think about Hodge theory?
Is the hype over?
Shitting Huddlehan - Thu, 16 Mar 2017 14:35:45 EST ID:vrOFV9fT No.15421 Ignore Report Quick Reply

Homology is bullshit, cohomology is bullshit. The only reason people care about that stuff nowadays is for some data analysis purposes, so that means people are interested in actually computing homology groups of spaces rather than this deeper stuff. The only people that care are topology nerds.

Connection between graphs and differential equations by Jarvis Pessledale - Tue, 14 Mar 2017 17:17:53 EST ID:ueMHQ1BO No.15418 Ignore Report Reply Quick Reply
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I am curious if anyone knows how to represent differential equations as a graph? I acknowledge that that sounds absurd, but I am curious, I know you can represent a graph via tutte polynomial, so I figured it's not too much of a stretch.
Doris Billingforth - Tue, 14 Mar 2017 17:56:07 EST ID:zpTgkQCY No.15420 Ignore Report Quick Reply
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What do you want exactly? It's not absurd to ask for something as a graph since graphs, like most kinds of mathematical structures, are expressive enough to encode anything you want to do.

A given differential equation will give rise to a dynamical system right? Like if I give you a point the differential equation can tell me the derivative(s) at that point. These derivatives are instantaneous rates of change, but you can imagine for each point in your space following the corresponding tangent vector for a certain time t. If your space is over the reals you will obtain an uncountable family of uncountably infinite combinatorial graphs which vary with t. Maybe you can study the corresponding operators? It looks like the sequence tends to the identity but the way it changes might encode information about your solutions.

Restricted movement by Ian Cinderworth - Sun, 26 Feb 2017 18:58:58 EST ID:ncb8UBjg No.15412 Ignore Report Reply Quick Reply
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I like to ask here, because it's chill here and I the thought of citing /math/ on my bachelor's amuses me.

Pic illustrates a truck with a trailer, reversing in a clockwise circle. The axles are illustrated with a green wheel on the end of each radius.
The axle on the trailer can be steered.
Suppose the wheels on the trailer are turned slightly, creating a new radius and triangle shown in blue.
So after the truck has reversed for a bit, shown in pink, I think the trailer would move like shown, with the triangle intact, dragging it's point C along the "old" radius of the truck rear axle. (Old being the instance where the new angle of the trailer wheels were established)
My questions are: Do I reason correctly? and How does the angle B in the yellow triangle change, according to the trailer wheel angle, the trucks turning circle and distance traveled? You see, I'm interested in the point where yellow A an B are equal.

What do you guys think about this equation?? by equation - Thu, 16 Feb 2017 21:56:31 EST ID:3CQShUbt No.15337 Ignore Report Reply Quick Reply
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Esther Dribbleforth - Fri, 17 Feb 2017 23:12:09 EST ID:A2j/BW/W No.15338 Ignore Report Quick Reply
>x = 0.0777...
>jk, x is infinity

Anyway, you fucked up the very first line. Should be 0.777... = 10x. From there, you can break up the lhs to get 0.7 + x = 10x. Subtract x from both sides: .7 = 9x. Divide by 9: x = 0.7/9 = 7/90. So 0.0777... = 7/90.
Beatrice Crenningmock - Sun, 19 Feb 2017 01:54:24 EST ID:A2j/BW/W No.15339 Ignore Report Quick Reply
And by "you" I mean whoever wrote that troll proof. I was under the impression it was your doing at first, but now I see you're just asking about it.

In that case, and looking at this with fresh eyes, I see that whoever wrote this is confusing (purposefully?) things like 0.7x with 0.7 + x.

0.7x = (7/10)(7/90) = (7*7)/(10*90) = 48/900 =

Whereas, 0.7 + x = 0.7 + 0.0777... = 0.777...

Or, 0.7 + x = 7/10 + 7/90 = 63/90 + 7/90 = 70/90 = 7/9

This confusing of addition with multiplication is the main theme of the "proof". The only things done correctly here are multiplying or dividing equations through by ten and the realization that a number subtracted from itself is zero (the number doesn't need to be infinity for this to work as is stated in the "proof").
Sidney Hummerwedge - Tue, 21 Feb 2017 00:04:06 EST ID:vrOFV9fT No.15340 Ignore Report Quick Reply

If you want to deal with things like 0.777 repeating it's best to use a symbol like a, rather than those fucking dots. Everything went wrong after the part in the rectangle in the attached image.
Fucking Grandville - Wed, 22 Feb 2017 00:08:02 EST ID:A2j/BW/W No.15343 Ignore Report Quick Reply
English use those dots instead of the vinculum. Chinese do too.

hex calc by CVF - Sun, 12 Feb 2017 00:53:25 EST ID:zOfzUnva No.15334 Ignore Report Reply Quick Reply
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good calculator that does hexadecimal? for school?
binary is a plus +
Basil Sinnerdedging - Mon, 13 Feb 2017 19:38:14 EST ID:A2j/BW/W No.15335 Ignore Report Quick Reply
Sophie Nennerstet - Mon, 13 Feb 2017 22:35:57 EST ID:ogPDtdlS No.15336 Ignore Report Quick Reply
If it's for a class use what they tell you. Otherwise use a smartphone, laptop, etc. It is what computers were originally made for, after all.

Top 10 favourite Integers by Colonel Badtouch - Fri, 04 Nov 2016 15:38:05 EST ID:9bYxsT36 No.15261 Ignore Report Reply Quick Reply
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Hey guys what are some of your favourite integers? Here's my top 10:
10. 34,236
9. 8
8. 457,893 ( I bet some of you thought this would be higher!)
7. 43.
6. 6 (Imagine that!)
5. 240
4. 9000
3. 7,777,777
2. 7, 777,771
  1. 108
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Jenny Gabberworth - Sat, 12 Nov 2016 08:43:59 EST ID:hLKFmGX4 No.15270 Ignore Report Quick Reply
You have good taste
Tom Waits - Sat, 12 Nov 2016 10:13:29 EST ID:jsJM/H7S No.15271 Ignore Report Quick Reply
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Cornelius Brorrypick - Tue, 15 Nov 2016 19:41:50 EST ID:zOfzUnva No.15272 Ignore Report Quick Reply
1024 512 256 128 64 32 16 8 4 2 1
binary maths are fun
Sophie Clishville - Thu, 17 Nov 2016 23:18:33 EST ID:IoPw+j1r No.15274 Ignore Report Quick Reply
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Every post in this thread starts with 15
Nigel Dartwater - Thu, 09 Feb 2017 18:17:46 EST ID:txB+9pVv No.15332 Ignore Report Quick Reply
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10. 15625
9. 11
8. 222
7. 6
6. 50
5. 7
4. 800
3. 22222222222
2. 2919
  1. -7776

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