/sci/ - Science & Math

I feel like making a meme chart. What's the best way to get graphics of book covers?

>>12344319
The publisher's website usually has a page for the book, and it sometimes has a high resolution cover.

>>12344256
>Is an oxbridge maths degree worth it? Would I be surrounded by autist assholes?
yes and yes

I want to undertake fluid dynamics for self study. I have a background in PDE's and linear algebra, but I had been reading tensor calculus might be useful too. How true is this and if so, what other fields should I study before I tackle the subject??

I've been interested in infinitesimal calculus. Is it worth to learn? what advantages does it have over standard calculus?

>>12344500
>what advantages does it have over standard calculus?
Holding onto outdated mathematics

>>12344500
None.

>>12344573
>model theory is outdated

9th for integrable systems

Any of you guys experienced with Bayesian stats? I've been reading a really great textbook on the topic, but it takes me a long time to digest some of the topics. Spent all day on like 8 pages yesterday. Just curious if anyone here has any preferred resources of their own or video resources. Most "Bayesian" youtube videos I find are of 30 something year old thots explaining the "logic" behind it and not actual lectures.

Pic related is what I'm reading.

>>12344319
What is it gonna be about

Can any anons help me prove this using delta epsilon? I can solve this under a milisecond but theyre forcing me to solve it using the epsilon shit which I absolutely despise.

>>12344964
maybe some inequalities would help

>>12344981
Definitely, although I have no clue what to do. Of all the dozens of sources I checked, only one has an example that is close to this one, but then they just remove the absolute value because the top becomes positive. The top here becomes negative if I set |TOP-LIMIT|<epsilon, hence no clue how to continue.

I like math but don't like studying. This year I started a degree in Mathematics, but although I like the subjects I don't feel motivated enough to study. What can I do? Has this happened to you, and if so, what did you do?

>>12345004
So I guess you like the concept of math and learning about new things but not going over what you've learned?

>>12345009
I like reading math but when I find some concept or explanation not trivially understandebale in a second I don't feel motivated enough to re-read it or to stop and look into it more carefully to try to understand it

>>12344998
Look at the proofs of the basic limit laws. They tell you how to turn the deltas you choose for say f and g into the deltas for fg, f+g, or f/g.

>>12345125
thanks friend

There are two ways a number could be a counter example to collatz, it could eventually go back to itself (if it doesn't equal 1) or it could just keep getting higher. I think I'm getting close to a proof that the first type of number doesn't exist

>>12345167
Many, many computer scientists have attempted the first part, all have failed to produce proofs which work inductively. You're not going to solve it.

I feel that linearity is a concept more broad than just linear algebra. Michael Atiyah (2002) talks about a passage from the linear to the non-linear in his article Mathematics in the 20th Century. He says "Large parts of classical mathematics are either fundamentally linear or, if not exactly linear, approximately linear, studied by some sort of perturbation expansion". ¿What does he mean by 'fundamentally linear' and what large parts of classical mathematics is he talking about? Is, for example, theoretical physics all about linearity?

>>12345415
This seems like a pretty soft statement, but my guess is that an area is «fundamentally linear» when the methods and problems of that area frequently involve linear algebra (or modules, more generally).

>>12344964
L’hôpital and if that’s not allowed just build the function from the canonical epislon-N relationship you fucking retard.
>>12345125
fucking idiot.
>>12345195
>computer “science”
not science, not math. this is your one and only warning.
>>12345415
He’s talking about linearization as in the process of converting nonlinear systems to linear systems as in differential equations and “differential systems”

>>12345526
Why are you such a faggot?

>>12345526
lmao what a touchy pussy faggot you are

>>12345556
why don’t you jump in front of a bus you little pussy brainlet

>>12345526
>>computer “science”
>not science, not math. this is your one and only warning
cringe

>>12345565
CS is not math and is not welcome in this thread or on this board. Off-topic posting is against the rules and will be punished accordingly. This is not a suggestion, you must abide by the rules for posting here or leave. If this displeases you make your own site where you deceive others as to the definition of mathematics.

>>12345574
>>12345568
Get off the internet if you're gonna be such a bitch lmao
Also what is computability theory you fucking loser?

>>12345574
>CS is not math
Dangerously BASED.

There are three /mg/s up right now, so I'm bumping this one to emphasize that it's the correct one because it doesn't have german in the OP.

>>12344964
I’ll do you one better and do it for (1/x^p).

So first off we need to prove that that approaches 0 as x goes to infinity.

And given we are taking a limit to infinity rather than to a finite limit, we switch it up and now must show that for every ε>0:

There exists: δ>0, such that if and when |x|>δ ->|f(x)-L|< ε

So do that. And given that 1/x^p, is monotonically decreasing, we assume it goes to 0, and prove its monotonically increasing by induction. Ask me for proof of you would like to know.

So with this: |1/x^p|<ε
Rearrange this equation and we get:
1/ε<|x^p| -> 1/(ε)^(1/p)<|x|

So remember we need a δ that is less than |x|, and directly impacts the epsilon equation. So we have one right there, and chose δ to be = 1/(ε)^(1/p).

So now you would have to then show that this delta works, and implies the etc. But that’s pedantic and should work. We worked reversely to find a delta using what we wished to prove.

Ok anyways now we have that.

And that is the hardest part, the rest will be much easier and I’ll write more. And just send you a picture.

>>12346529

[math]\bullet[/math]What textbooks, papers or text did you read today?
[math]\bullet[/math]What non-textbooks did you read today?
[math]\bullet[/math]Did you write something today?
[math]\bullet[/math]Did you do some programming today?
[math]\bullet[/math]Did you build something today?
[math]\bullet[/math]Did you clean up something today?
[math]\bullet[/math]Did you plan something today?
[math]\bullet[/math]Did you manage to work off some bureaucracy/paper work today?
[math]\bullet[/math]Did you practiced any skills today? If so, which?
[math]\bullet[/math]Did you do sports/cardio/weightlifting today?
[math]\bullet[/math]What were you eating today?
[math]\bullet[/math]How much sleep did you get yesterday?

>>12346727
none
none
shitposting only
no
no
my asshole after I shat
no
no
no
same routine I do every morning
fish rice meat eggs
enough
dont even think of asking these questions again round these parts, bub
its sunday, not workday

>>12346688

>>12346886
I also made the mistake of switching n with x, but I hope you know what I mean. But that’s my solution. Ask any questions. And yes, it’s pictured weird, but just download and fix it yourself. I don’t want to spam this board with corrections.

Have a great day. Jesus loves you.

>>12346727
today i did a large portion of the dumb administrative shit on my phd applications, which is something i am very happy i did
now i have grading to do

I've noticed from a shitpost thread that [math]-1^{1.7} = (-1^{0.1})^{17} \neq {-1^{17})^{0.1} [/math], and it surprises me that I'm learning pdes and haven't internalised the tules of complex exponentiation yet. What can I read or do to fix this?

>>12348094
I fucked up the latex. Should be
[math] -1^{1.7} = (-1^{0.1} )^{17} \neq (-1^{17} )^{0.1} [/math].

>>12348109
>>12348094
Disregard both of these, I've realised my mistake.

>>12348113
This is just from Wikipedia. Post it in all the other threads shitting up this board

>>12344964
factor out n^2 from numerator and denominator
1-1/n+2/n^2 / 3+2/n-4/n^2
1-0+0 / 3+0-0
1/3

How do you guys cope with imposter syndrome? I'm currently working on a take home exam in a graduate class that I have 99% in, but this exam is insanely difficult. It's making me feel so stupid. I even feel physically ill just thinking about it.

[math]2^2[/math] is easy to calculate.

>>12348672
[math]2^{2}[/math] is easy to calculate.

>>12345035
then maybe you just don't like math that much?

>>12348672

>>12348579
Imposter syndrome is just narcissism. If you think you can really fool everyone else into thinking you are smart, you must think everyone else is really dumb. Get over yourself. If grad school doesn’t make you think of quitting often, then you aren’t going to a good program.

>>12344284
>/mg/ - maths general
Hi /sci/,

can one of you math-guys come here >>3625935 >>3626076 and explain to this anon how math works?

He's seriously embarrassing the rest of us.
Thanks in advance.
cheers.

>>12344284
>/mg/ - maths general
Hi /sci/,

can one of you math-guys come here >>>3625935 >>>3626076 and explain to this anon how math works?

He's seriously embarrassing the rest of us.
Thanks in advance.
cheers.

Group theory is abundant with "discrete threshold theorems" of the form: Such and such holds for all groups of type X whose order/dimension is [math]n[/math], provided [math]n[/math] is large enough. For example, the alternating group is simple iff [math]n \ge 5[/math], and the Euclidean group is unsolvable iff [math]n \ge 3[/math].

I'd like a quick brainstorming sesh: What are the most significant such theorems that come to your mind, *whose cutoff value is [math]n = 3[/math]*?

>>12349093
The alternating group of size n+2 is simple iff [math]n \geq 3[/math].

>>12349458
Fucking faggot.

Unironically transphobic and fagphobic.

Choke to death.

>>12349464
I was a making a joke, but it turns out I was replying to a fascist scum. We on /mg/ do not condone any form of discrimination. Please kindly fuck off.

>>12349568
Uh, I'm the OP of >>12349093, just wanted to
clarify that I'm not this anon >>12349464. So let's not get worked up and start throwing feces at each other. How about we actually discuss math instead?

>>12348672
Depends on the type of your [math]2[/math]

>>12346770
>its sunday, not workday

every day is math day

>>12349568
You will never be a woman.

>>12349755
You will never be a man.

>>12349755
>>12349766
You will never be tenured.

>>12349770
You will never leave your mom's basement.

>>12349770
You will never have sex.

>>12349755
You're quite wrong on this. I transitioned successfully already.

What are the relevant fields of math that are useful in being efficient in trading stocks? I know statistics but what else?

What's the coefficients [math] c_{n,m} x^n [/math] in

[math](1+x)^y=\exp(y\cdot \log(x)) = \sum_{n,m}^\infty c_{n,m} x^n y^m[/math]

I suppose what I can read of from the behaviour at 0 and 1 s that
[math](1+x)^y=1+xy+\cdots [/math]
with other terms already cubic.

I expect there's a relatively nice formula for the coefficients, presumably a sum of products of something elementary.

I've been stuck for ten minutes, can anyone help me. I need to give an example of a set of real numbers with a definite first element, a definite last element and infinitely many elements between them.

>>12350375
Doesn't any closed set of real numbers with more than one element satisfy those requirements?

Out of curiosity, what kind of fucked up notation is [math]Z/Z2[/math]? It's not that hard to specify order-2 group.

>>12350375
>>12350381
Any closed set on R with a finite interval will do. So the set [1,5] for example has a definite first and last(1 and 5 respectively) but infinitely and uncountably many reals between them.

>>12349991
L O N D O N

>>12350375
Really?

>>12350008
Stonks are more about understanding market psychology and following the news. You can analyze it with fancy math, but that's only useful if you want to get into bot trading.

>>12350508
What about gut feeling and a firm handshake?

>>12350384
Number theorists get autistic whenever anyone tries to use [math]\mathbb{Z}_2[/math].

>>12350384
Basically number theorists go:
>NOOOOO THAT'S THE P-ADIC INTEGERINOS YOU CAN'T DENOTE THE MODULOS LIKE THAT NOOOOOOOOOOOOOOOO

quantum algebraic topology when?

>frame of reference
>axiomatic
>assume
you know some heavy shit is about to come when you see this

>>12350153
I missed 1+ in the exp expression.
Looks like I posted this 5 hours ago and nobody gives a shit.

>>12350153
>>12351114
this page pretty much gives you the answer: https://en.wikipedia.org/wiki/Binomial_series
i hope you can figure it out from here

>>12349991
>I transitioned quite successfully

I’m a math grad student. We don’t want your kind. Hang yourself.

>>12351225
mhm, yeah sorta - except it's not actually an expansion in two variables.
That said, you reminded me I had actually written it down before

https://en.wikipedia.org/wiki/Stirling_numbers_of_the_first_kind#Generating_functions

thx

Okay, I got it refactored to

[math] (1+x)^y = \sum_{k=0}^\infty \sum_{n=k}^\infty \frac {1}{n!} \left[{n\atop k}\right] x^n y^k \cdot \frac{1}{(1+x)^n} [/math]

Not completely there yet (because of the nested sum indices and of course the 1/(1+x) factor, but it's a good benchmark)

What's a good textbook that covers Time Series properly?

>>12344769
I'd be happy if I could do 5 pages.

>>12345415
Locally everything is linear.

Do you know of someone implementing a sort of open key encription based on nonograms? Just thought it was a nice puzzle type for encription, but I don't think it'll be "fast".

Do undergrad britbongs use Rudin or something else for analysis?

>>12351452
Wth are you on about >undergrad Brit bongs

Is this even a question?

Are you asking for a book in real analysis?

If so, yeah, rudin, best bet. Comprehensive and concise.

Why is normal distribution the most viewed math article on wikipedia? Is it racists reading the bell curve or morons struggling with basic math?

>stuck on problem
>take nap
>wake up and know the solution to the problem

is there a better feeling?

>>12351543
>morons struggling with basic math

this one, to my experience. the normal distribution gets referenced a lot in papers that circle around the arts (e.g., history types sometimes have papers with statistics-derived conclusions about geology or something like that) and arts students, as most who talk to such people will know, believe that the best way to learn about something is to read up on it and have something to say about it, rather than understand it

is taking (sum(|E[x]-x|^n))^(1/n) useful for any n other than 2?

>>12351543
>Is it racists reading the bell curve or morons struggling with basic math?
yes

>>12351597
The notion of "useful" is probably ill-defined.
n=1 is probably half as bad

>>12351577
>Dream about solution
>Wake up early and full of energy amd start writing math
>Feel good the rest of the day
Greatest feeling

>>12351543
maybe a lot of people look it up because almost any kind of statistics in any field of science can lead you to "normal distribution"? i mean it's very cross-disciplinary

yo /mg/ you think if I polish off Tao's Analysis I and Axler's Linear Algebra I'll be able to do VI Arnold's ODE book without much issue?

I'm self-studying so assume I can only go to the internet for help/solution verification. Also if someone has a better suggestion for Linear Algebra than Axler please let me know, I haven't started yet.

Daily reminder that [math]2 \in 3[/math].

>>12351760
And [math]1 \in \cup 3[/math] .

>>12351745
Axler is for faggots. Do Kenneth Hoffman.

Two analysis is ok. I used rudin real analysis and the “papa rudin”.

You got some weird ass books. Sounds like a physicist faggot.

Oh yeah ofc. You see one. Just looked up Arnold typical.

My advice is to rope yourself.

But for sure if you don’t want to be brain dead. The best linear algebra book. Concise and comprehensive, is Kenneth Hoffman and Ray kunze.

>>12351745
>Also if someone has a better suggestion for Linear Algebra
Do it on your own (without a book).

>>12351745
I can't help you with Arnold's as I've never read it (heard good things though).
I self learned LA through Friedberg and Hoffman & Kunze's books. The explanations are really clear, particularly in Friedberg imo, and H&K is rather comprehensive. Also there are solutions online if you need them sometime.

>>12351778
How?

>>12351773
What's weird about Tao's Analysis?

Arnold came up as a geometric treatment that someone on some website stated could be tackled with analysis and linear algebra as prerequisites, but without providing much detail as to how much of both subjects.

I'm not a physicist, but I do have a full-time job that pays me well but takes time away from math, which does make me different than someone like you, for sure.

>>12351801
Thanks!

>>12351810
Fair.

I saw Arnold and noticed a lot of his books were oriented for physicists.

I’m neurotic and quick to jump.

Anyways two isn’t weird, it was the other two books. Nonetheless, most people chose rudin. Though being different isn’t bad. As I said. Just a note.

It was the axler and Arnold that made it smell like a physicist.

Anyways yeah sorry. Good to know someone else agrees with my suggestions so my suggestion doesn’t die because I acted like an ass while trying to help. Sorry. Have a good day.

>>12351806
Here is a summary of results in linear algebra:
https://www.imperial.ac.uk/media/imperial-college/faculty-of-engineering/electrical-and-electronic-engineering/public/msc/Linear-Algebra.pdf
Go through each one and prove them all on your own. It's not that hard.
The only think I see missing here is the definition of determinant, which you can look up on wikipedia, then I'm pretty sure the pdf is self-contained.
The last page contains some exercises as well to test your knowledge.

>>12351869
Here's an example how you go about it:
>The following are examples of vector spaces:
Here your job is to actually verify (prove) that the spaces discussed are vector spaces.
In the next point, you need to understand why the examples are not vector spaces.
There are many points like that. Just go through each one and prove them all until there are no logical gaps and until everything that is said there is clear. Whenever you see a statement which you don't find clear that means it's your job to prove it.
Once you've gone through the sheet, you should have mastered basic linear algebra.

>>12351773
>>12351842
You're one weird dude, phonefag

What age did you decide you wanted to devote your time to mathematics?

>>12351608
as in has anyone used it for making sense of data for say n>2

>>12351842
I appreciate the help, I just have to dish a little back when I get told to neck myself, you know how it is. Thanks for the recommendations!
>>12351869
Interesting, I will check the page out. I will definitely need to avail myself of books or websites to get to the point where I can complete that though, so I do wonder of that's on my own.
>>12351952
Unfortunately age 23, because I misunderstood what math was for a long time

>>12351952
14-15. It was CS when I was 12, then physics when 14, and somewhere in between I lost interest in physics.

>>12345167
It's already been proven that any chain would have to be extremely long

>>12352021
Like my cock

>>12352021
Do we know if there could be infinite chains?

>>12351978
>I will definitely need to avail myself of books or websites to get to the point where I can complete that though, so I do wonder of that's on my own
Still spend at least a few days trying to prove all the results on your own so you see what you're dealing with and so that when you actually read a book on linear algebra you recognize things and see their importance in relation to your own struggles to prove things.
You should also go through the whole sheet and at least understand what it's talking about.

Can you guys recommend me a book on ODE? I started reading Tenenbaum's book and while I liked that he was very specific not to refer to solutions as general except when they contain all particular solutions, I dropped it after he never justified separable equations, even though it's easy to do (He instead replaces dx by delta-x and then argues around the topic).

Can someone explain integration to me? The class I'm taking is working out of Abbott's "Understanding Analysis" 2nd ed. The book starts talking about how integration was initially defined in terms of the antiderivative and briefly glossed over problems with that and moved on to the Riemann formulation. My question is, what properties must a function to have for an antiderivative to exist? My professor said something about Lipschitz continuity, but didn't go further. And what is the connection between the Riemann Integral and the Antiderivative? Thanks in advance

>>12351842
Does Axler really smell of physics though? It seems really math focused. The prime example of a course that uses it would be Math55a and it's pure math. At my school physicists use Hoffman, even.
Arnold, well. He said " Mathematics is a part of physics. Physics is an experimental science, a part of natural science. Mathematics is the part of physics where experiments are cheap." so.
>>12351978
Doing LA on your own is a bit of a forced meme. That said, trying to prove theorems as you read them is really rewarding in LA, even if you haven't proved much of anything before.

>>12352157
First of all, your thread belongs in /sqt/. Do not post in /mg/ again as your level of math knowledge is way too low.
>My question is, what properties must a function to have for an antiderivative to exist?
The simplest condition is that the function is continuous. Although there are weaker conditions which ensure existence of antiderivative, they are not as nice. What you want is for the function to be integrable.
>And what is the connection between the Riemann Integral and the Antiderivative?
This connection is the fundamental theorem of calculus.
https://en.wikipedia.org/wiki/Fundamental_theorem_of_calculus

>>12352203
>Doing LA on your own is a bit of a forced meme
No it's fucking not. Stop saying this.

>>12352151
The Dover books one. Most comprehensive. This is for lower division though. Diff eq gets harder, but usually it’s lumped with diff geo. So if you’re just doing lower division ODEs. Do that. If your school has ODEs after, say idk analysis, then don’t listen to me.

But it’s the most comprehensive. I would like someone to make this post better. Universities do things differently so idk.

>>12352298
It's definitely worth doing something on your own at least once. But that something should be discrete math, not linear algebra, especially since the "linear" aspects are very difficult for autodidacts with little math experience to do right.

>>12352298
It is tho

>>12352330
I did it on my own in a university. And it worked. I haven’t had problems. Infact when you go to uni it’s more independent learning. So you’re retarded.

Everybody has their own learning methods. In my case, I don’t like professors or teachers do I teach myself. That’s how I got through HS. I just taught myself and it worked much better. When I was in middle school I always went with teachers and learned nothing. It was only till I moved past that did I actually learn soemthing, rather than have it flushed over summer.

And it’s how I’ve been going through from freshman year to real analysis. So far. And it’s just how it is. If you have questions, ask yeah. But self learning works for others and better than others. So don’t pill push others. Let people learn the way they want to and if it works, it works.

Professors tend to confuse me and I do worse when I listen to them. And I watched online lectures and they are shit. When I read the book and go through it myself it’s better, and I can ask questions sure. But I don’t ever use 1 person to learn.

>>12352357
But to be fair I didn’t learn LA directly on my own. How I got through it was by diff geo. I tried to teach myself, and it took too long. So I skipped, and went to diff geo and real analysis and using those I learned linear algebra by applying it.

Nonetheless it was on my own, and worked, I passed the class with an A. And once again am doing real analysis from my previous year of learning. In uni.

>>12352305
>>12352151

that is tenenbaum. Imo it's tedious as fuck that book. Personally, I don't really understand why anyone would want to learn 10^5 solution techniques that they'll forget and never use.

If you like math for its own sake, and you've taken analysis, I've heard Arnld's book is beautiful but challenging

>>12352357
Which books did you use for this self learning?

>>12352372
It’s not a tenebaum. It’s doable for anyone, I just tried a lot. I’m not very smart. I also just have bipolar, so mania helps, also aderall. If I’m a tenebaum I don’t feel like one. It seems like everyone is the same level of intelligence as me. Everyone I gifted in their own right, and what would stop them is not trying. And I have a lot of depression. This isn’t good and I often want to kill myself.

This is do able for anyone, you just have to try. I know this may loose credibility. But I want to let you know this is doable for anyone and I’m not special. To make it so, I got a 28 on an exam I did for geometry in high school. First exam, but I picked myself up. I got an A on the final semester grade and a 3.7 gpa for the year. I moved often so it was always hard to adapt to schools. This is doable for anyone. You just have to try.

What I noticed is that I stopped this. And why I stopped was because I was told it wasn’t realistic and I followed. I let myself tell myself that I couldn’t do what I already had done. If you constantly bring yourself down and say that it’s unreasonable you’ll never try and see how good you can be.

I just want to tell you that you can do it and it’s possible. It’s not just me or anyone or Einstein. Einstein got shitty grades for his other courses in college. “Genius” as people think is hard work and a little luck.

I don’t know if this works, but I just want to tell you. TRY. Just try. Oh also.

Search gregorious maths and Fematika on YouTube. They also did what I did and more. Gregorious maths went from fucking middle school to K-theory in ONE year. And he is apparently trying to publish a paper at 13.

Don’t be de-motivated and say that it’s just the person. It’s not. Try. Try and if you don’t, don’t worry. Aim high and set the bar low. But don’t forget to AIM HIGH.

You need to aim high to atleast try. Dont lower the bar and aim low because of it. I felll into that trap.

>>12344769
I'm curious why you're using this book. Are you just more interested in the math than the applications? It seems like lottos the info is kind of useless, no? I haven't taken a closer look though, so I could be wrong.

That being said, Gelman's lectures are probably great. If you're interested in ML stuff, there are hundreds of videos on anything you want (variational inference, GMMs, inference on linear dynamical systems and hidden Markov models, variational auto encoders, etc.).

If you're an absolute beginner MclReath's lectures are on YouTube, and while they're made for people with little to no mathematical training, he has lots of good insights imo.

>>12352407
The list is too long. But I used the books on the list in the discussion page for this channel:
https://m.youtube.com/channel/UClenF9iK45e3oEvmjR2OpZw/discussion

I made it to real analysis, linear algebra, PS topology, Loring tu, I’m reading spivak rn, first volume. I’m finishing Riemmanian metrics. And I also did the basis for the list, hope it’s obvious. I also am trying to go through diff top and AG. But I haven’t had time because personal issues.

Once you get to that point you can read any in any order. For the most part.

There’s also this 8 year old called Andres, but it seems like he deleted his channel, and he did Liouvelles theorem at 8 and apparently went to uni.

>>12352452
Sorry to hear that you want to kill yourself at times, and it's great that you're doing well in maths, but I was saying that the Dover edition book that the poster replied to is by an author named "Tenebaum" (or maybe the name was tenenbaum?)

But yeah I didn't like that book much.

>>12352293
>Do not post in /mg/ again

>>12352489
Weird place to get a list of books from

>>12352768
It was on /sci/ discord server, and a list. There’s a nicer text file. But I’m not going to tell you to join a discord server and wait.

The list was made by him when he was a moderator of the server/ later admin. But he left and hasn’t been found for months.

Nonetheless it’s a good list, and also when you try to copy and paste here it doesn’t work. It’s too long and counts it as spam. But he left the list on his channel so I sent you that.

>>12352768
https://m.youtube.com/watch?v=WNfI1udpLJo

>>12352489
how old is this guy? he's in this ironic anime gamer phase that teens have and he has spongebob merch and what I assume to be a bunk bed.

>>12352844
Lmfao. He said he had the bunk bed and spongebob hamper when he was little and just didn’t feel like replacing it.

He was 16 7 months ago if you look at one of his diff geo videos someone asks that.

And yes, he was 16 and an admin of the sci server lmfao. And that’s not even the start, the owner was also 16 when the server was made and the only other admin was 15 lmfao.

The real mind boggle was the owner, which means the mods of /sci/ endorsed a 16 year old to host the server lmfao. But the kid at the time was in uni to be fair and was studying real analysis.

Honestly too idk why the age limit for this site isn’t just 16, given that a lot of European countries have their AOC at 16, or atleast based on region. Like if you’re in USA it’s 18, then if you’re in the UK it’s 16.

But also this is a US based site so that’s why. Still ironic.

>>12352844
He has videos with his face in it. He's obviously young. Or some cursed ass genetics I guess.
https://www.youtube.com/channel/UCIUPBxtBMQvssqSbx73t8SQ
There's some young math inclined people on YT, like link related, previously mentioned. Was a bit of a meme now that I remember, years back.

>>12352874
>>12352867
the absolute state of /sci/ lmfao

>>12352867
It's because they type like you, christ

>>12352948
Kys

>>12352874
>Was a bit of a meme now that I remember, years back.
Cope.

>>12352985
Huh? He was, though. I'm not saying it in a despective way

Can someone give me an example of an R-module which is cyclic but contains an R-module which is not cyclic. I know that R necessarily cannot be a PID but I'm having trouble coming up with a counterexample that makes sense.

If you had to force a single undergrad math topic into a couple 30 minute lessons of high school algebra because the lesson plan is empty, would anything be better than basic linear programming? Is intro graph theory more appropriate? I think this is a joke from the senior faculty but I'm not in a position to fight it.

>>12353513
That’s an odd placement.

But given it directly effects you. There should be something.

But I’m not going to answer the question because I don’t know. I will tell you what I know about graph theory and linear programming.

During my algebra 1 class we actually had some programming lessons, it was shoddy, but nonetheless it was programming of some kind. And it worked well.

I will also say that for someone to like graph theory, especially if they’re forced to do it, they would probably want to also have programming and some application for insentive and to enjoy it. For my high school we had a CS club and they would often bring up elementary topics in graph theory and understood it well, though they had the prerequisite of algebra 2. So I would suggest have a hybrid of graph theory and programming for algebra 2, then basic programming for algebra 1.

I wouldn’t say there would be anything better because programming is the hot stuff right now and everyone wants a piece of it. So that would be a good bet. I can’t think of anything else.

But also, honestly, algebra 1 is kind of dumb. And it’s dumb they teach it at schools. They say it builds logic, but it doesn’t it’s math. It’s rustic calculation and it’s retarded.

If you want a logic course, do one, and that’s called discrete maths, which have no math prerequisites than a math maturity. It’s insanely retarded. I’m a math major and it’s fucking stupid. Nobody remembers algebra and nobody cares, honestly, only time is for the meme. Even fucking PEMDAS, someone literally spammed that shit on this god fucking board. Most people are nigger retards and most leftist pink hair dyed retards won’t understand and bitch about how algebra was hard and they don’t remember it. It’s fucking stupid. It doesn’t teach anything than waste your fucking time.

If you want logic, again discrete mathematics, or just do a fucking logic course because they exist.

In Europe, Spain,

>>12353551
I know someone who is doing some ethics course and it’s actually decent. Amerifat is fucking retarded.

And I’m speaking as an American. Fuck this stupid country and it’s stupid government which has the senate stay in office for a millennium, while the president is on rotation every 4 years.

What's a better PhD? Applied Math or Statistics?

>>12353564
Neither. You’re retarded.

Those two choices are abysmal PhD choices. Unless you mean specific applied math. If you mean general you’re fucking autistic. But for specific, like physics or a natural science, or engineering, yeah applied math. A PhD in stats is fucking retarded and useless. No offense to stats, Infact if it’s a BA, that’s fine, but PhD? Retarded. And so are you for considering it. It’s a waste of time and a waste of research. Applying stats is beneficial, and if you want to get a PhD in something related to stats to combinatorics or probability for a thesis in pure math.

>>12353551
Sorry, I'm not a student taking a prospective course, I'm a private school math teacher who's been given an odd instruction from the senior math lead and two other senior faculty have backed it up.
I've only been teaching since March 2019 so I'd appreciate it if anybody else has a clue here. I can't post this question somewhere more reputable without probably doxxing myself.

>>12353625
Of all places then, why did you chose 4chan. Like are you serious?

>>12353625
You already said, but still that’s ridiculous, what do you expect to come from here. Half of the board is riddled with /pol/ retards and the other half is children.
Whatever.

>>12353630
I'm on here all the time already, what difference does it make? I don't even have to adlib the class until Friday.

>>12353625
Idk who you think I am. But I took those courses in uni. And that’s what I found when I did them.

>>12353625
moore method it lmao

>>12351363
lads?

>>12351101
Are you a physishit or something?

>>12352293
>First of all, your thread belongs in /sqt/. Do not post in /mg/ again as your level of math knowledge is way too low.

If you were in my department, I would bully you to death.

I solved the RH, AMA.

>>12353594
What about MSc in either. I'm finishing up my BSc in Applied Math

>>12353742
Tooker?

>>12353747
Sure.

>>12353753
Really?

>>12353742
Post proof or gtfo fag

https://math.berkeley.edu/~ribet/250/

How is this from an official, well respected university.

>>12353756
It’s in my head. It’s too complicated. Because I calculated it for all reals. And I can visualize it. But it’s hard for anyone normal to see.

>>12353757
Fuck off chud. Wear the mask FFS!!

>>12353759
Bait.

>>12353755
Yeah. That’s fine. A masters is pretty good for that.

So the thing with a PhD, is that it tends to be for research, so if you want to research in that field, and most are professors or work for the govt. idk, you go for that.

That’s why it’s really difficult, and for any university. For a PhD more often than not you would need to write a book practically or do some reallly really good work.

So much so, that most grad students tend to already have dozens of papers finished. Low hanging fruits. And low hanging fruits doesn’t cut it for a thesis more often than not. You are expected to do research and further the field by an exceptional margin.

Which is why I said that’s stupid. Statistics and Applied math is a waste of PhD and research, and so god awful. And most of them are for applications. Those are job oriented and a PhD in either one is fucking stupid and a waste of time.

But a masters, it’s not close to a PhD, a masters, the dissertation requirements is stupid. If you look at flammable math’s dissertation it’s like a HS research paper. It’s dumb. And even so a lot of PhD students tend to get their masters in the process.

Nonetheless it’s an upgrade from a bachelors and shows, well mastery, it shows you are solid in the subject, but don’t care for research. This is good for jobs and general work in the field. And if you’re into that go for it. But if you’re going for a PhD or should be useful or else you’re wasting your money and your time and a lot of fucking work for some shitty field nobody cares about.

So yeah go for a masters if you really are adamant on applied math and stats, which it seems like you are and you are stuck.

Though, I know people who have switched, for example someone from Lebanon who majored in EE, and switched majors, and he is now a grad student in pure math at some prestigious French uni, and doing very well and should be done soon.

>>12353784
>That’s why it’s really difficult, and for any university. For a PhD more often than not you would need to write a book practically or do some reallly really good work.

xDD

>>12353784
>>12353551
>>12352867
>>12352489
>>12352452
reddit spacing

>>12353881
I’m on mobile and I like spacing. I learned it from someone I loved.

Anyways zoomer detected for caring. You’re retarded. And the Reddit meme is retarded. I don’t like Reddit and think it’s fucking stupid. But it’s been harassed so much that at this point it’s just dumb and like kicking a transgender while they’re down. You’re kicking a sad, pathetic, mentally ill retard.

This is the only website I use. And just started 3 days ago, again. And I deleted all my social media. So kys. I only have YouTube and ocassionally create accounts on dating apps or sexting apps because I’m lonely and got dumped.

This is problably bait but idc. I have a brain tumor.

>>12353919
Bæsd.

>>12353757
...what's the problem with it?

>>12353757
Soul!

>>12353742
did you use the neighborhood of infinity?

>>12353440
Ask in /sqt/ and I'll answer.

>>12354730
God you’re pathetic.

Stop being such a fucking faggot. And quit it with that bullshit. There’s a reason everybody thinks you are a pathetic loser. And you should probably listen to yourself and kill yourself. The word is better off without your kind.

In this triples problem, instead of fucking about with different functions and double factorials is it simpler to declare a step function over the naturals that takes 0-9 to 2, 10-99 to 3 and so on? Like number of digits +1?

>>12353440
[math]\prod_{n \in \mathbb{N}} \mathbb{Z}[/math] as a regular module contains the non-cyclic submodule [math]\bigoplus_{n \in \mathbb{N}} \mathbb{Z}[/math]

>>12354750
Cope.

>>12353919
The average 4chann(el)er

>>12354805
is it allowed to go from binary -> decimal?

>>12354805
The remainder are left as an exercise to someone else.

>>12354805
Probably simpler to just do 2+2+2 = 6 and substitute the remaining digits [math]2 = \lceil \sqrt{3} \rceil = \lceil \sqrt{\sqrt{n }}\rceil [/math] for n=4-9, because this method extends more consistently to the higher naturals.

>>12355261
sqrt x is forbidden in the problem

>>12355663
Nah, cbrt is. Reread the image.

>>12355170

>>12355756
Baaaaaaaasedboy

>>12355756
>forgot the eight
Gotchu senpai.

Doesn't a group action [math]G \times X \rightarrow X [/math] just form a subset of the monoid [math]G \cup X [/math]? Or would it just be a semigroup?

>>12355892
how is [math]G \cup X[/math] a monoid, i mean you have no operation on two elements of [math]X[/math]

>>12355892
If B is a subgroup of A and C is a subset of B, is C a subgroup of A?

>>12352814
>The list was made by him when he was a moderator of the server/ later admin. But he left and hasn’t been found for months.
So, this is who is LARPing as anime trannies in this general. Fascinating. Really makes you think!

help me bros, I need to prove this basic inequality but my multivariate calculus is a little rusted
[math]x^{\theta} + y^{\theta} \leq (x+y)^{\theta}, \ x,y \geq 0, \theta >1[/math].
I think jensen inequality might help me but i'm still stuck. Thank you

>>12353722
(x/(x+y))^theta + (y/(x+y))^theta <= x+y/(x+y)=1.

>>12353722
There's no one in this thread that could bully anyone to death. You're all very physically weak and poor. If you have no power you can't do violence to others.
>>12356038
learn to LaTeX and don't give free answers to retards who spend no time trying to solve problems.

>>12356038
Thank you, it was way easier than I thought.

>>12351760
Daily reminder that this expression is not well typed.

>>12355970
just define one lol

can't we just concatenate elements of [math]X[/math] on the left and the right and call it a day? and we just define it to be closed, so any concatenation of elements in [math]X[/math] is fine, and elements [math]g \epsilon G[/math] just act on these concatenated elements.

I think this works regardless of the order of [math]X[/math]

I guess to me there's no obvious reason you couldn't just impose these structural restrictions to see that a group action is a boundary on a definable extension to a monoid, but I admit it might just be a silly question to begin with

>>12345009
Not him, but what you said applies to me. I love understanding and grasping new concepts, but once they are grasped they don't interest me anymore. Hence why I often skip exercises.

Hey /mg/, how many universities and math institutes are going to go back to in person activities during the first semester of 2021 in North America and Europe?
How many have already decided and what is the chance of them deciding to return?

>>12356016
the inequality is homogenous so WLOG we can assume x+y = 1
then use single-variable calc to look at lefthandside and it follows pretty easily
i remember i've once seen the solution with jensen but im too dumb to remember

>>12356119
It must be pretty easy to delude yourself into thinking you understand with no reality checks.

>>12350384
Z/(2) or Z/2Z is the proper way to write it desu

>>12350694
Yes.

>>12356016
Fun fact, using proof as in
>>12356038
we can prove that in general
[math](\sum x_i^p )^{1/p}[/math] is decreasing for [math]p>1[/math].
So
[math]\frac{d}{dp} \left[ \log(\sum x_i^p )/p\right] \leq 0 [/math]
and this reduces to the claim that (taking general [math]x_i[/math]) for all [math]\pi_i >0[/math] s.t. [math] \sum \pi_i=1 [/math], we have
[math]\prod \pi_i^{\pi_i} \leq 1[/math]
Which obviously follows from the general AM-GM but I think it's a cool proof nonetheless.

>>12354805
(S((a+a)/a))! for a>0

>>12356338
Nice

>>12356338
S is not canon.

is khanacademy good to get a basic understanding of calculus?

>>12355892
A group action is a functor from G.

Is there a [math]C^k[/math] version of stone-Weierstrass theorem?

Am I right in thinking that although there is no total order to the complex plane, any set of complex numbers that lie on a straight line that also intersects the origin have a total order within the set?

>>12356694
>there is no total order to the complex plane
False. There are many total orders on the complex plane. They're just not compatible with the field structure.

>>12349991
hazel?

>>12353758
Proving it in your head is easy. The hard part is writing it down so that others with no intuition understand it.

post most based professor you met

>>12356795
where is this place?

>>12356852
It's on the roof.

>>12356597
It's my headcannon.

>>12356687
There certainly should be. Simply approximate uniformly the kth derivative with a polynomial and then integrate, making the right choice for the constant of integration at each step so that the integrated polynomial remains close to the lower order derivative. You may need to start with a polynomial which is epsilon/|b-a|^k if your interval is [a, b] or something though, I suppose the error would increase as you integrate.

Is a career in academia really that great? All my professors seem depressed as hell. I’m having trouble seeing why one would take such a pay cut to work in academia vs industry, since the latter is diverse enough that there Has to be something of interest. I’d understand being a professor if one was actually interested in teaching but obviously this isn’t the case for the vast majority of mathematicians, who cannot even feign interest in the material of grad level courses.

>>12356795

I want to get deeper into number theory. I've done a fair bit of elementary number theory and a little analytic number theory. Enough to have understood proofs of Dirichlet's theorem on primes in arithmetic progressions, the prime number theorem etc. I haven't done much in algebraic number theory and would like to dip my toes in the water . Also next year I'm doing an honours thesis on linear forms in logarithms. Any reading material would be greatly appreciated.

For reference I have taken undergrad courses in real analysis, complex analysis, elementary number theory, some basic abstract algebra, metric spaces and measure theory. I feel these are the most relevant anyway.

>>12357543
i only went into academia because i wanted to avoid working 8 hours 5 days a week
instead, now im worrying about my phd 24 hours 7 days a week

Is there an easy way to identify chain rule applications vs product rule applications? Sometimes it's hard to distinguish a 'function of a function' vs a 'function times a fuction'

>>12356601
Yes, absolutely. But I'd also recommend Professor Leonard and Studypug.

Can I cum in such a way that it produces a cubic graph?

>>12356193
How exactly do you get that [math](\sum x_i^p)^{1/p}[/math] decreases and how does derivative being negative imply the result?

>>12356193
>>12357777
Nvm, I get now how to prove the norm decreases but still don't understand how you deduce the result after claiming derivative is non-positive

>>12357777
Checked
You can think of the derivative as a rate of change. For instance, for a function y of x, if the derivative is 2 at a certain x value then increasing x slightly has the effect of increasing y by twice that slight amount. Similarly if your derivative is negative than increasing the x value has the effect of decreasing the y value (or increasing it by a negative amount).

>>12357610
>I want to get deeper into number theory.
literal popmaths though

>>12356729
>>False. There are many total orders on the complex plane.
name 2

>>12357751
>Sometimes it's hard to distinguish a 'function of a function' vs a 'function times a fuction'
like when?

>>12356119
>I love understanding and grasping new concepts, but once they are grasped they don't interest me anymore.
>>12356141
>>It must be pretty easy to delude yourself into thinking you understand
Exactly me.

>>12356099
>can't we just concatenate elements of XX on the left and the right and call it a day?
not elements of G ∪ X

>>12357845
Yes, I do understand why the derivative is non-positive. I did't understand how the rest follows, namely, [math]\prod \pi^{\pi}[/math].

>>12356141
I prove everything for myself in my head retard. You don't need to drill exercises like a robot to understand unless you are simply stupid.

>>12344284
I'm start me some Tao Analysis today, wish me luck fellas, I have 2 weeks to read it through

>>12357897
>building your opinion based on the common opinions of others

How do I prove it? I'm clueless.

If you get an idea for an application while reading a research article, is it ok to just send an e-mail to the author asking if he considered it before.

Part of me is sperging out and afraid of embarassing myself, but I don't want to waste a month exploring a dead end if the author of the paper tried it before.

>>12357900
lexicographical order favoring the real part
lexicographical order favoring the imaginary part
idiot

>>12357948
niggas laugh at gender studies until they get hit with the list of 10233028913 genders to memorize

>>12358047
haven't done analysis in forever, but it probably comes out looking like 1/n+1 if you massage the |xn-1| a bit.

>>12357942
What's the highest level math book you've read?

>>12357833
>>12357777
>derivative being negative imply the result
Compute the derivative and tell us what you got.

>>12358063
Thanks, it is something
But still how?

>>12358078
get rid of all the fractions and see what happens

How do you cope with the fact that you'll never be on Tao's level?

>>12358109
doesn't make me very mad, i'm not at Tao's level, but almost no one else is at Tao's level
these days i'm more mad about being a poorfag
i mean, being top 0.1% mathematicians among all people is nothing
but if you were in the top 0.1% of all people in terms of networth or income, you would be fucking rich
and if i stay in academia in my europoor country then i'll be poor all my life

>>12358128
How can you be poor with a PhD?

>>12358109
I'd be happy being smarter than 50% of mathematicians both in general and within my area of expertise, and more importantly, if I could specialize in the field I'm mort interested in (which is something that I'm already failing at).

>>12358109
>I NEED to be the BEST
If you don't stop thinking like that right now, in 2-3 years time you're going to be a leftist of the oversocialized type. Just do things that you think are fun and fulfilling

>>12358065

>>12358109
I don't give a shit, I'm not twelve

>>12358157
Which field? How are you failing?

>>12356131
Someone answer me, please.
At least tell me about your own universities.

>>12358142
Poor life choices/terrible perspective on life

Imagine being good with numbers and not using it to build wealth.

>>12358182
Why don't you do a research on it instead of begging to be spoonfed here?

>>12357543
Do you have a vagina?
The academic world will welcome you with open arms.
You are Caucasian, and (correctly) identify as a male?
Stay away, you white, racist, sexist, patriarch pig.

I wish I was exaggerating there.
I'm done with my masters next year, and am glad to be able to bid farewell to the academics.
It's largely (real-life) hear-say, but it's ridiculous how many lives have been ruined by the academic system of our time.

>>12358109
I never even think about that? I just like doing math.

>>12357543
Everything is academia is prestige-based. Your career is based on who you know, who you pay lip service to, how many councils you've sat on, etc. Undergrads (and even some grads) seem to think your job is sitting in an office dreaming about math all day. In reality, it's proofreading papers and going to conferences to vie for the attention of the main speaker.

Given a population of m, that has k subpopulations of n1, n2, ...., nk elements each, and a sample size r:
How can we calculate the amount of different subsets with r of the m elements, ignoring the order of the elements and considering all the elements of the same subpopulation unrecognizable form each other?

For example: m=6, r=4, k=3, n1=1, n2=2, n3=3 ((ABBCCC))
The possible subsets are 5:
ABBC, ABCC. ACCC, BBCC, BCCC

Bros please i dont now if there is method for this because it certainly asnt in my classes. I tried this but it doesnt werk
[math]\frac{m!}{(m-r)!r!\prod_{i=1}^{k}n_{_{i}}}[/math]

>>12358212
>be idiotic conspiracy nut professional victim
>turn people treating you like a normal person into "I'M BEING OPPRESSED!!!!"
stay out of academia, you're not cut out for it.

>>12358237
ups sorry i meant
[math]\frac{m!}{(m-r)!r!\prod_{i=1}^{k}n_{_{i}}!}[math]

>>12358237
i meant
[math]\frac{m!}{(m-r)!r!\prod_{i=1}^{k}n_{_{i}}!}[/math]

>>12358142
i'm not a phd yet, just a phd student in math in the poor parts of europe
a phd employed in the academia here earns around 15k$ yearly (after taxes)
many of my friends who went into CS have found jobs in USA or england as codemonkeys and they're earning literally 5x or more than me

>>12358270
where are you form and why cant you solve this >>12358237 ??

>>12358212
>You are Caucasian, and (correctly) identify as a male?
I'm a brown third worlder cisgender and male though, how fucked am I?

>>12358303
>brown third worlder
Rest assured. The affirmative action-PhD is already reserved for you.
Do your best, and everything will work out fine for you.

>>12358164
Somehow I'm not surprised...

>>12358329
On the serious note, I did not mean to say I grasp things instantly. Rather, instead of doing exercises which are boring, I take 20 minutes to ponder on the idea, fiddle with it in my mind, try to arrive to the conclusions I just read from the basis I already know etc. Often times I arrive at mental blocks which indicate that I did not properly understand something, at which point I reread, reinterpret and generally just repeat the process. I am learning through activity, like with exercises, but it's much more interesting and stimulating.

>>12358344
this.

>>12358316
>Rest assured. The affirmative action-PhD is already reserved for you.
Thank God. I fucking love America!

>>12345035
Don't be a coward and reread it

>>12345035
by doing this you are literally learning nothing
source: i'm doing the same

>>12358254
Sorry, offtopic, how to pass a formulas like you did?

>>12358408
https://b060e7a4-a-62cb3a1a-s-sites.googlegroups.com/site/scienceandmathguide/other/-sci-infographics/joseflatex.png?attachauth=ANoY7cqmkyithWHCellpbCMKQoB132IbymRDP8BH-1S-niGwDgZ13U67qlU94r4LMk_tiqsPO5dW34F9mWDx3-xEf6dM1gPXJHIvbUz-fSHr5gZdBE_SpI3vqx6TlYZjyF2-TEwVBRsPTZt_19EsyYzQZfStoXxy_TNR0Ky_NMJV8Bu-m8a_zahun1AeVz6ZX4pnCeSgrySNXFEYpRfytsLUGlp--6X1t-zgroETUOhhO8O-I-LcjQlM2JBNg9_-A6fSdLzNJRqw&attredirects=0

>>12358344
You honestly sound like me when I was a clueless high schooler. Let me repeat the question: what's the highest level math book you've read? I really doubt an experienced mathematician would share your opinion.

>>12358065

>>12358628
Interesting. So are you saying that you're doing the exercises in your head or do you just ignore them altogether?
>try to arrive to the conclusions I just read from the basis I already know etc.
Do you mean you try to prove things yourself before looking up the proofs, or are you trying to find new proofs of the theorems?
By the way, are you a PhD student?

>>12358649
I'm not that anon

>>12358303
don't listen to these bitter weirdos. It'll help you, but you still have to be competent. No PhD program is going to accept you just for being brown obviously, but it gives you a leg up.

>>12358649
I didn't see that >>12358065 was a response and not general question

>>12358657
>>12358661
Oh lol. For a moment I was very surprised. Anyway, just out of curiosity, what's your opinion on exercises?

>>12358619
Depends on what's high for you. Abstract Algebra I'd say. Take note I self-teach, I am not constrained by exams or applications of my knowledge. I am on linear algebra now because I kind of skipped it(together with calculus) due to the fact they simply weren't interesting(not that much now either). However, I soon learnt that linear algebra is at the very least referenced if not heavily used in things that interested me, so I am coming back to it now. I am aware that all this might sound like beginner level for you(I probably am), but the approach I take is very effective in that I fully understand everything I've read by pretending I am proving and explaining it to someone else(and everything else I wrote previously). The only downside is that I take lots of time to go through the material(again, not a problem because I have no time constraints). I am open to your views as someone with most likely much more experience than me. You may improve my studies in the long run.

>>12353564
do whatever you like better. Stats is easier if you want to go into industry research after, but if you don't like modern research in the field, you'll want to blow your brains out trying to do a PhD.

>>12358665
if one wants to become an actual mathematician (i.e. be able to solve unsolved problems), doing exercises is absolutely necessary. depends on what do I mean by "doing exercises":
an undergrad benefits from doing every single exercise and carefully writing everything down into fully readable proofs
a person with more mathematical maturity is fine with doing exercises in their head or skipping the trivial ones - but that's only because they've already been through the undergrad phase described above

how do I write pic related in latex?

>>12358844
\Big\lvert \lVert x \rVert-\lVert y \rVert \Big\rvert

How often do you mistake "soon" with "anon"? A professor ended his email with "see you anon". Does he know?

>>12358869
Very zoomer of you to post this, zoom zoom zoom-kun.
https://dictionary.cambridge.org/dictionary/english/anon

>>12358854
Looks kinda ugly, but thanks anyways

>>12358844
\| does double bars [math] \| [/math]

What is the worst experience you've had TAing?

>professor makes you grade 100+ projects with unique problems for each student

>>12359028
Getting a breakout room full of fresh off the boat Chinese in Zoom.

>>12358844
|||x||-||y|||

>>12357900
1| a+bi < c+di iff (a < c or (a = c and b < d))
2| a+bi < c+di iff (b < d or (b = d and c < a))
And a bonus for you
3| a+bi < c+di iff ((a is rational and c is irrational) or (a and c are both rational, and a+bi < c+di according to the order 1 defined above) or (a and c are both irrational, and a+bi < c+di according to the order 2 defined above))

>>12359028
Can't rape anymore cause of covid

>>12359028
I don't mind grading, even for "creative" projects grading them is mostly menial work I can do while I watch YouTube videos.
The worst part of TA'ing is dealing with 80IQ fuckwits who shit the bed on the exam and then try to haggle their way into a better grade by trying to convince me that I didn't grade their diarrhea fairly.

https://www.strawpoll.me/35144221

What pen do you use?

>>12359707
Do webfriends count?

>>12359707
I have a GF but I'm not sure I would say I have plenty of friends. And they're not quite normie either

>>12344284
For this volume, I'm getting -1 + 1/infinity. Can it just be |-1| = 1?

>>12358109
I honestly don't care

does it feel good to prove something?

>>12360092
yes

>>12360092
Yes. And automatic proof checkers make it feel even better imo.

>>12358628
that's surely among the ugliest book titles I came across

>>12358047
isn't N usually a number and not a set? [math]\forall n \in N_{\epsilon}[/math] doesn't make sense

>>12360225
oh is that supposed to be [math] \mathbb{N}[/math]

>bomb the shit out of calculus III this semester despite getting a high A in ODEs last semester
>depressed and discouraged so now self teaching PDEs and having a great time with it
names for this feel

>>12360248
>failing Calc III
ngmi

>>12360254
that's the point I bombed calc III but aced diffeq so I don't know what to think

>>12358237
There's no simple algorithm, and it relies on the inclusion/exclusion principle. Consider the simple case where k=m, is [math]{m \choose r}[/math]. Now try figuring out how many items we overcounted, considering instead if k=3 with such n1, n2, n3 as you described. For instance, consider the sets of 4 we would choose, in the simple case, that contain 1 C. Without considering their unrecognizability, you would count 3 times too many such sets by choosing 3 indistinguishable Cs. Thus, that set of subsets gets pared down proportionally. You must do this 'paring down' with each group of 1, 2, 3, etc. taken elements of nk for each nk.
Here is a link to the solution http://mathonline.wikidot.com/combinations-of-elements-in-multisets-with-finite-repetition

>>12360255
if you're good at math you don't bomb undergrad, simple as

>>12360417
actually that link describes an easier way where you consider each ni=m essentially, and then remove the elements counted that have too many of each ni

>>12360426
that's what I thought until coronachan, ADHD, and OCD fucked me 7 ways to sunday, and one extra way that I didn't know existed and can't be described with an analytical solution

New thread

>>12360554

>>12358047
Doesn't [math]x_n[/math] converge to 0?
The denominator is a quadratic, while the numerator is linear.