#serious-discussion
1 messages · Page 166 of 1
Putting things at the end feels like it enables you a bit more to be like, okay here you don't need to think much about the underlying field, okay now we're talking R and C
This geometric interpretation I feel can honestly be skipped. I never really found it especially illuminating, and it always felt like it was just done as an obligatory thing.
Clear partition
This is fair. Truly that might belong in a measure theory class
It's not even really a R^n thing, it's just a R^2 or R^3 thing specifically. There's no geometric intuition for parallelipieds in R^37 or whatever because we can't visualize that
It formally still works if we have a notion of measure, but that's formalism that linear algebra students can't be expected to have and developing it is a bit of a diversion
I feel like very clearly stating assumptions in theorem statements can be helpful here by the way. If we have
Theorem 1.3.7. Let V be an arbitrary vector space over some field F. Then...
Corollary 1.3.8. In the case V=R^n, we see that...
Oh wait a second I think I found a way to make the R and C case not an interlude
It might get annoying, but at least when I learn a math subject that's basically how I do it anyway. Big theorem in a general case, then apply it to my toy examples and see how it behaves.
Previously it felt like a random interlude in an otherwise smooth story
Buuuuuuuuuuuuuut
The first thing I'm gonna talk about in multilinear algebra is bilinear and quadratic forms
🙃
So the flow from here can be
- Bilinear and quadratic forms
- (R) Inner product spaces
So okay the way it's setting up is, let's say if it's in book form for simplicity (though I don't anticipate writing a book anytime soon, this is my mental model for teaching a class)
- Chapter 0 is preliminaries, the first bullet point
- Chapter 1 is generalities, so the next 3 bullet points
- Chapter 2 is coordinatization, so the last 3 bullet points
- Chapter 3 is bilinearity, so bilinear/quadratic forms and then inner product spaces (so the geometry kicks in)
- Chapter 4 is multilinearity (esp determinants)
- Chapter 5 is structure theory (eigenstuff, char/min poly, canonical forms, spectral theorem)
- Chapter 6 is analysis
- Chapter 7 is cool applications (SVD giving low rank approximation to matrices, maybe orthogonal polynomials, maybe a bit of error correction via LA over finite fields, stochastic matrices/Perron Frobenius/Markov chains?)
How does that sound Zorn?
Also @storm sage you I think would be interested/have good thoughts
I still feel a little bit weird pedagogically about the placement of first iso and rank-nullity relative to eachother, but I understand the logic.
Also @JohnDS and @bronze pelican
Where are norms? They don't really fit the idea of bilinearity, so probably not there. Are they being saved for structure theory? If students get well-acquainted with inner products first then "norm generated by an inner product" is a nice example to have.
Multilinearity in char 2 
Structure theory? How do they fit in there?
If anything I almost think maybe I should insert chapter 6 = analysis
now that I think about it
And chapter 7 is cool applications
Not structure theory, I think I was thinking they were originally chapter 4 but they weren't multilinear so I guess the next one
got a silly question, if someone can please clarify
I guess in principle there can be some talk about norms throughout but a full systematic treatment of norms might come later
Stuff like equivalence of norms in finite dimension, matrix norms, probably matrix exponential in fact
If we do chapter 6 analysis, then norms would definitely fit there
You might want to check out #❓how-to-get-help
If a book, I think a good absolutely batshit crazy idea would be to include a chapter on TVS. The goal isn't to use that for a standard course, but to have it there as reference material or for those kids who like the course to read the chapter over the summer or maybe for a project or... you know, whatever
boom posted
HAH maybe. Tbh this was mostly a thought experiment since Higher was interested in what I had in mind but it kept getting put off due to time
That itself came about since at some point I whipped up some quick ideas on how I wanted to present a first year calc class
(TVS by the way stands for Tmean Value Stheorem)
#discussion message that message, for reference
Every time I do this I wind up reinventing baby rudin.
Not in a ton of detail but yea
This one I was a bit more conservative on than Baby Rudin wrt the topology, but I did more algebra
(I'm still here!)
just lurking this conversation very hard lol
Oh I figured
I was just giving the context, like no I'm not quite writing a book this is just an interesting thought experiment you proposed
Also because like aside from Bourbaki I don't really know of a good source on TVS specifically, the theorems are just all around the place in other chapters of FA texts
We're not writing a book yet. Once we publish this thing, we'll put Axler and Hoffman-Kunze and all the rest out of business.
Yeah tbh I don't think much about TVS other than Banach spaces and maybe their weak topologies
And in the latter I just say hmmm okay some of the theorems probably hold if you replace "Banach space" with "locally convex TVS" I think/hope
Though really I do need ot do more functional
We have a crew on here that I think just has a good mind for the cognitive model for math
I'm not gonna say I have a mind for pedagogy because tbh I probably don't. My pedagogy is trial by fire
I keep saying that I feel like in 5-10 years, with the people that we have here, I reckon this server is going to become a real powerhouse in the math world
But the cognitive model for how pieces fit together?
I think yeah I'm decent at that for sure
Polish cafe round 2 lez go
Like we're not all there yet, but "yeah all these mathematicians met on a discord server as students" might just become the future textbook's version of
Yeah basically Polish cafe 2 electric boogaloo
New OpenStax?
Honestly we have a nice spread researchwise too
Or like Bourbaki group 2.0
Yeah, it's quite unfortunate. Everyone should study what I'm studying.
We should be studying four majors
Brain off right now
Actually speaking of what people are studying
Is this an analysis oriented course
John will be ecstatic to know that at this Philly conference I'm at, my talk is listed as "Geometric Group Theory/Dynamics"
Right now qual prep and FA on the side. I should also probably try to teach myself AT and manifolds or ODE/PDE for one of those quals but
Idk Lotka Volterra but least squares is a good inclusion yeah. I guess I forgot about it since idk much and my impression was that it's just
Oh
Distance is L^2
Minimize that
Geometry
gg
It doesn't stick out super strongly in my mind
Oh, I didn't quite wanna include ODEs in here, I assume people don't necessarily know that
I think it's worth including an aside on just in case
Damn I should call her to say RIP
hello
Maybe don't make fun of people with aids though? That's just a douchey thing to do
Born to do math
Forced to do physics
Also not necessarily
Study the parts of physics that turns into math 
I reckon like, we could write a book with a fairly large number of optional sections. There's going to be LA classes where everyone in the room has taken calculus, and so introducing basic ideas of systems of ODEs - even if just for a lecture or as optional side reading - wouldn't hurt
then we can start recommending our lin alg book in #book-recommendations 
Just linear algebra
It's kinda "I like almost everything so I want to include almost everything" lol
Study all the math to understand physics

The chapter stuff I gave was an outline but I wanna include as many points of view as possible
Born to do math
Forced to do bio
The @native oriole story
there's already too many linear algebra books
Gram-Schmidt is taking a basis and turning it into an orthonormal basis
It's also a deformation retraction of GL(n) to O(n)
It's also QR decomposition
Also if this is a class I am definitely gonna have people do stuff on computers
Maybe compute a few examples by hand to make sure they get the point
But they're learning numpy
Or matlab or whatever else
Introduce fourier series in the section on change of basis as an optional section
I was gonna include it in the inner products section
Which comes after
This is incredibly based
Ah yeah that also makes sense
But yeah I won't just do R^n with dot product
I want to talk a bit about Fourier series and about orthogonal polynomials
Nah
Physics is empirical fundamentally
No mathematical statement's validity depends on the results of an experiment
Truth in physics relies very crucially on experimental evidence
Counterargument: String theory
I mean
If string theory turns out to make a concrete prediction that's disproven
It becomes dogshit physics
With no value
So it'll have mathematical value alone and cease to be physics
It proves... that Dami is a physicist and not a mathmetician 
If turns out to be correct
Then it'll be a claim that a mathematical model correctly overlays onto a physical system
Wha
Ha you're a physicist
If anything I'm being an armchair epistemologist right now smh
That doesn't make you not a physicist.
If anything that just confirms that you're a physicist.
But epistemology is much more math than it is physics smh
You can't make me use bra-ket
I won't do it
?
May anyone suggest any books which discuss functions in the perspective of set theories and linear algebra? homomorphisms, linear maps, transformations and such please someone
If you scroll up you'll see that me and amin are writing one now
Have you tried searching in #book-recommendations ?
A book?!

Imagine if the book is like 30% linear algebra and 70% applications
It might be
So... most LA textbooks?
what branch ?
Even better 20% linear algebra and the rest ist just plain analysis.
Thing is there are too many cool linear algebra applications
I mean the actually cool stuff
Error correcting codes, orthogonal polynomials, Markov chains
Maidenful applications you feel me?
Idk. Never really enjoyed linear algebra all too much till now.
Book title: "Introducton to Linear Algebra"
Table of contents:
Chapter 1. Linear Algebra
Chapter 2. Banach and Hilbert Spaces
Chapter 3. Bounded Operators
Chapter 4. Spectral Theory
Chapter 5. C* and von Neumann Algebras
Chapter 6. Unbounded Operators
No. I mean like the lectures and stuff were like meh
So I didn't really activate my self study interest mode
Yes!
I want a signed copy though
._.
calling this "Introduction" is so hilarious. I approve! 
This also feels like the wrong order
Yeah unbounded should come first
Every problem will be a cleverly disguised open problem
Arbitrary exercises will be starred to indicate that they're harder.
They're all hard.
lol
From the contents I know like 40-50 %
I guess
Don't know if I just translated them wrong
Might be more
Dami's is real. Mine's a shitty joke; the idea is that it's actually a functional analysis textbook
Dami is actually going to write this book? 
Would it be a crazy idea to try and shoehorn some representation theory into an intro linear algebra course?
:(
But it's a serious proposal for what he'd do if he ever teaches LA
Probably a bit crazy
I mean the thing is how you'd do things depends a bit on the surrounding classes
yes, I asked him to make this proposal 
We definitely need a math book from Mathcord
My kinda hot take is that if I were designing stuff from the ground up
I'd actually want a fair bit more algebra in first year than is typical
Huge sale on Springer right now‼️
It ends in like 8 hours or less
Quick question guys - does Springer let you print out the Ebooks i buy from them??? Or it doesn’t offer pdfs, so I have to read them from their site???
Huge thank you if you know and can answer🙏
piracy
🏴☠️
Yeah I don't understand why algebra is often introduced so late. Especially something like an intro algebra course at the Pinter level or so could easily be a first year course at the level of calculus or LA, and yet it's often taught in the 3rd year of an undergrad degree
So what I would probably do if you really gave me full control ground up is this
I would want the group theory surrounding permutations and arithmetic, and then enough ring theory to show that if corporate wants you to find the difference between Z and k[t], the answer is "They're the same picture"
Wait why are Z and k[t] the same 
Really what I mean is the fact that they're both Euclidean domains
And the story that ED => PID => UFD
All euclidean domains are isomorphic.
This is a famous result called "Daminark's Theorem"
Oh yeah dami have you seen my proof of the largest composite number

I wonder if you can do addition on N^N in a way that coincides with the addition (Z^+, +) on N^⊕N = (Z^+, ×)
they obviously give you pdf access but it's a waste of money
literally just download them for free like everyone else does
But @vivid halo what if you don't find the book you're looking for?
this basically never happens to me
Can't agree on that part.
skill issue

This only happens if you're trying to get a book that's been out of print since the 1970s, or if you're trying to get the brand new edition of a pearson book that came out several weeks ago.
Wdym, you mean when you cannot find pdf?
fwiw, there have been cases where I have been unable to find biology textbooks to download on my friend's behalf
mostly because biology books tend to get a new edition every couple of years, and the newest editions simply haven't been... freely distributed across the internet yet
Yeah it sucks when that happens
its a specific C*-algebra, specifically the ones with a predual
fascinating
this is the worlds oldest sundial, from ancient egypt
and u can see daytime is split into 12 hours
what reasoning could they have had for this
the babylonians used the a unit of time which was about 2 hours (thus daytime having 6 units)
this makes sense because the 12 zodiacal signs rotate once per day
so u have 12 signs per day, 12 units of time ("hours") per day
12 being from... their sexagesimal system i guess?
they split the year into 12 equal segments of 30 days each (ignoring the last 5 days) and then that naturally gives you 12 zodiac signs based on which constellation the sun resides in
i wonder why the egyptians decided to split daytime into 12 hours
especially since their zodiac system had 36 signs "decans"
maybe it was arbitrary
These predictable heliacal re-appearances by the decans were eventually used by the Egyptians to mark the divisions of their annual solar calendar. Thus the heliacal rising of Sirius marked the annual flooding of the Nile.
This method led to a system of 12 daytime hours and 12 nighttime hours, varying in length according to the season. Later,[when?] a system of 24 "equinoctial" hours was used.
hm
doesnt explain how the 36 decans gave rise to 24 hours
but apparently they did
Sometimes I search for a book and I don't find a free pdf for it.
you try harder
It's not like I don't try ._.
also fascinating
the first decan according to the egyptians was called sopdet
which is their word for sirius
this is apparently equivalent to the first 1/3 of cancer
but sirius is just.. so far from cancer
strange
Intimately related
Hello.

nG might help you overcome this skill issue.
I can't live life without free PDFs
Hello
hello
are you talking about zlib?
#help-31 message please help!!!
Yeahh and few more
few more? are there another things?
What that bruv
Yeahh there are
Honestly internet is vast
can anyone teach me matrices?
hi hi
one nice thing about this figure is that it is quite easy to draw freehand, by first dividing into four and then each section into three
i’ve no idea how they would have done it though
oop but i promised myself i would go to uni today so i have to get going right about now
bai
i have officially left for uni mwahaha, but will take my sweet time getting there
as an experiment
lol wut
no, i set realistic goals
and occasionally overshoot
oh
you good? I need you.
what the hell man
bat man
srry, #help-45 needs help. I'm stupid and don't understand it
If you don't, I can get north
lol
what tablet should i buy for math surface ipad or samsung
i used a samsung
Today minecraft is unplayable thats make me leave video games related
I think I should continue my scientific work
yea we have had issues and there is a huge power outage close to where i live
something is up
Character development
Haha
what kinda work you got?
Students
Owh sorry
Hmm
Derivative influence for science
Its simple
i barely know derivatives
just finished algebre I
algebra*
isnt deravitive d/dx?
In college?
Yup
me smart
cool
I am going into physics next year
atleast half of it what I heard is about quadratics
and I actually liked quadratics
so im excited
Quadratic is foundation
fr
You learn trigometry?
thats also next year
I assume you are grade 9
im taking tons of stem + math classes
yea
so next year is
Accelerated Geometry
Accelerated Algebra II
Accelerated Trigonometry
Intro to Probability & Statistics
Accelerated Chemistry
Astronomy
Electronics II: Physics
so im just planning to take alot of stem
Seems college
Hold on
Owh no doesn't matter
I learn above grade 11 too
just looking for some general advice but would it be best for me to study algebra 1 or geometry over the summer?
are you at a STEM magnet school?
intereesting
you can choose either, but algebra 1 is better if you want to study calculus in the future
Euclidean geometry is beautiful though
I mean you didn't specify, Cartesian geometry also definitely helps with calculus also
otherwise called coordinate geometry (but that's a bit of a dumb name cause there are many different types of coordinate systems)
oh wait so what are you going to do in physics, cause it's called electronics lol
also astronomy is pretty cool
not everywhere is like the US where they offer so many course options
cause your high schools can have like 2000 students or something, so there's that economy of scale
Physics in Electronics correlates with Amperage, Volts, and how they travel quickest as possible
that would be unthinkable in other places to have so many
it also reveals the thermodynamics behind it
Maybe I'll try a bit of both I will need it and I plan on taking Calculus sometime later I'm probably going to focus on algebra for now tho, thanks.
ah okay so electricity
I mean I thought you were doing Raspberry Pi and stuff
lol
technically im going to be in Pre calc next year
no worries
since Accelerated Algebra II explains integrals
Any suggestions for like videos or websites for me to learn, I plan on doing virtual next year and I just wanna be able to find like notes and good explanations.
isn't that just straight calculus then
yep
pre calc briefly explains the first 2
after sophmore year
junior year will be
uhhh
This math video tutorial provides a basic introduction into algebra.
Full 1 Hour 44 Minute Video on YouTube:
https://www.youtube.com/watch?v=gPedjnN1OEM
Direct Link to the Full 1 Hour 44 Minute Video on Patreon:
https://bit.ly/3hzqpqb
Here is a list of topics:
- Adding and Subtracting Like Terms
- Properties of Exponents
- Multiplyin...
org chem tutor and prof Leonard on YT for videos
Khan Academy for practice
also from around video 110 they start covering algebra 2 content
AP Probability & Statistics
AP Chemistry
AP Pre-Calculus
Accelerated Physics
Math Investigations I
my junior classes
stem
it really depends
what grade you in?
if you can keep up the practice I'd say 6 months, well it always takes longer than you think
I'll be starting 8th next year i just wanna try and skip some classes if I can
It will definately take you 6 months
basically assuming that the standard curriculum of 9 months in a school year is 3 months of bloat
but like it's important to learn this stuff well and thoroughly, like understand why things work like that
not all of the topics will be carried on to further study but they're kind of good to know, it's a bit silly to justify it like that but yeah
Most of Physics relevate around Quadratics, Calculus, and Trigonometry
also I like this playlist cause there's some revision on fractions
but Physics is a VERY complicated thing
percentages, number problems before you start on linear functions
exactly
yeah I mean all the physics you are learning will be an approximation of the truth
but as you learn more and more, the approximations get closer to reality
like a limit tending towards some value
but never reaching it
This is not true
Wait oh it has calc
why do people think sending a image of the question verbatim is a good way to ask a question
a lot of the time, it's because they don't know how to properly ask a question
as in, they cannot figure out exactly what it is that they want to ask
I think it's better than an hour of xy problem though
xy problems are awful
not just that but also
what's the misunderstanding?
what are xy problems?
person wants to do Y and ends up trying to use technique X but can't get it to work, so they ask about X
but don't mention Y
so you end up trying to help them with a really weird specific thing X, which might not even be the right thing to be doing in the first place, rather than actually helping with the problem Y
allow me to present this gem
(this was yesterday)
TIL theres a term for that, cool
it's a term from tech support iirc
!xy
Please show the original problem, exactly as it was stated to you, with the entire original context. A picture or screenshot is best. If the original problem is not in English, then post it anyway! The additional context might still be helpful. Do your best to provide a translation.
I disagree about picture or screenshot but I imagine that empirically it works better for people that are horrible at asking questions
but like i don't get how you don't gain this ability to ask the question
like
I want to see Xela go into the help channels for a day or two 
surely one notices the place that one stops understanding
what would be the expected outcome
i did for like a very small period of time, less than a day
and what happened
took a long time to determine what the damn question was
yes, that happens a lot 
one needs a good amount of patience to help people in those channels
but like how does one not know how to ask a question like this
it just seems automatic to me
like i should obviously provide enough information for the person answering to understand what's going on and for them to know where i got stuck
all i need to do for this is to state the question and then go "and i didn't understand [bla]"
Let's take something valley helped me with a while back.
Fulton and Harris at one point stated "thus, the representation is determined by the character on the cartan subgroup"
after writing down things on a board and looking again at the thing preceding that statement i managed to reduce this to a linear algebra problem
it hinged on "is the matrix you get from this invertible?"
Oh good debate
i gave some details (not enough to in the end actually finish the proof, because i didn't forgot to mention an important restriction on these matrices and thought that the other restrictions i mentioned were sufficient) about the matrices in question
Valley suggest gershgorin, using the example matrix i provided, and i believe he also prodded me here about whether it actually was diagonally dominant so that gershgorin could finish it
upon reading this i realized that the restriction i forgot was important and finished it
Now, imagine that instead I just said
It's an earned skill I think
Ah right. You are forgetting the most important factor
Laziness
pretend the underlining and writing isn't there
there's a lot of people who are either too lazy to ask properly
imagine i just posted this and said "halp"
or else they are so confused that they don't know what to ask
and they are just looking for someone to hold their hand
But I only started asking questions like this when I started discording on mathcord!
I know I am better at introspection than most
And I know the kind of things someone would need to answer the question
Hmm, then I guess it hinges upon how much effort one will put.
Many just like to leave things out to someone else, being hopeless, wanting others to help them up to the end
to be honest, the users who ask proper questions are the ones who already have some idea of the problem at hand
Also number of times people just asked for answers 
the ones who just post a screenshot or picture and say "help" usually have no idea what's going on
Like generally I give the definitions of things and especially anything that I'm not sure is standard.
Like
"Suppose we have a semisimple finite dimensional lie algebra over an algebraically closed field of char 0. We can do the root space decomposition like [bla] where bla is bla.
Now, it is claimed that [statement]. But I have no clue why/I tried this and got stuck/isn't this literally false"
are there vcs
that's usually how questions are asked in the advanced channels, from what I've seen
not anymore
that's the good way to ask
moderation difficulties
damn
i'm going to two parties tomorrow
the help channels, pre uni channels, and early uni channels have a lot of questions that just go "halp"
lol
Now I feel guilty, I asked questions like
- how to even cohomology compute do
Or
- How even differentiate over ring
i imagine you probably asked it better than you think
there's also the people who say smth along the lines of "okay, I have a test tomorrow and I don't know ANY math AT ALL. SOMEONE PLEASE HELP ME OR I'LL FAIL OMGOMGOMG"
(I am joking, hopefully I was better than that)
The most cryptic of my questions are when the author has made a cryptic statement.
yeah but the issue there is different lol
It can be largely similar
mhm
"0+0 =? hardest problem in all of math!"
a highschool graduation party of my highschool closest friend and a birthday party of someone i haven't met in meatspace yet!
me when nonunital monoid
i have a test on petting my cat tomorrow and i have NO IDEA how to get to him.
wait do monoids need an identity
please help me i need to find him otherwise i fail
fuck wait i can't remember...yes right
depends on the author 
Yes it does
the most frustrating people to help are the ones who refuse to cooperate, for whatever reason
oh right if they don't it's a monod
But it's just a naming
monoids dont need inverses i believe
correct
Semigroup denotes one without identity
if they did it would be called a monnnoid
Tbh I wonder if semigroup is ever truly useful
a monnoid is just a group
and is magma non-closed?
You can always adjoin identity
welcome to the help channels! we have:
trolls
ghosters
cheaters
people who want you to do their work for them
yes i "used" it
i think
I hope you enjoy your stay!
might have been something else
Hm
semi group of units of the octonions or something
as a green name this is bad pr for the server 
Isn't this monoid?
only a matter of time till the mods censor you
my bad 
uhhhhhhhhh
Well it would also have inverse
not associative
I think most of the green names (and the mods who work in the help channels) would agree with me though!
I thought Octonions are associative algebra
no!
,w octonion
(right?)
the mods make ad revenue off server activity didnt you know
Tf
when will I be paid to put up with the helpees
the point is that g2 is to octonions as su2 is to quaternions
Nonassociative multiplication 

that is, lie algebra is to lie group as malcev algebra is to moufang loop
don't ask me about those two i have no clue about them
so you can take e1 e2 = e4 and get the kther multiplications by uhhh a certain set of operations like cyckically permuting
or soemthing
it's "divisibility" since there's no identity
and it's a quasigroup iirc for just magma + divisibility
Why no identity?
the algebra nerds are at it again
tbey certainly have id
I mean a magma with only inverse
ah
not octonians
Nonassociative algebra is just so 
lie algebras are nice
Ah btw @fresh comet what are you working on nowadays?
nothing new 
I've been on summer break for the last month
my fall/winter semesters ended a month ago
The semester from September to December is called the Fall semester, and the one from January to April is called the Winter semester.
May to August is the Summer semester
I have a couple of courses rn, that run from May to June
so half semester courses
kinda
Ah interesting, I would imagine there would be Spring semester
tbh, calling the semester that runs from January to April the "winter" semester is kind of stupid
idk
I would call it the Spring semester
but eh
what've you been up to, Absta?
Yeah me too but i guess it is decided
Hmm I've been just following coursework, some alg geo and differential topology
Tbh also learned class field theory but it seems to become unholy mess
What kind of courses you taking, higher?
not math, at the moment
I'm finishing up my "breadth requirements"; I think one would call them "gen eds" in the US
so I'm doing a philosophy of science course + a very very basic geology course 
Ah, gen eds. Bane of university students 
Do you like it?
I guess it depends on person
yes 
I'm also taking driving lessons rn
and some other stuff is going on in life
so I feel super unproductive with maths atm


I hit... 1.02k messages in the last 24hrs
yikes, could've spent that doing smth productive

oh yeah Absta, did you see this
#discussion message
Being productive by avoiding such might be overrated tho
Oh wow
Bots channel can be fun!
Yeah I do discord too much 
if you do discord too much, what does that say about me 
I'm nearing my 30 day message peak now...
only a couple dozen more messages to go

Xela could be insurmountable tho
Also some of your messages is just typing t!top in #bots so
I'll get top 3 again for sure
a lot of them are 
Time in discord may seem inflated for you
last time I was rank 3 with this many messages
almost rank 2
but rank 1 was more than both of us combined 
O, that's an improvement!
more messages is improvement?
don't forget my GIF spam in #chill, or my keyboard smash posts
You are lower in rank now
Yeah you are not dedicating too much time in discord!
even discounting those posts, that's like 9.5k messages at least
which is a lot still 
is differential equations that hard? 
depends
wdym like does it depend much on integral calculus or something?
What was it, the PDE for aerodynamics
PDEs 
It is a Millenium problem, so I'd say it can be pretty difficult.
integration is a must for diff eqs
Navier-Stokes 
im about to study DE in my next sem I hope I survive 
good luck 
hellour
You got this I believe!
I love me some Navi stokes 
go to sleep
You should not use discord after waking up early 🙃
i'm not
You should help me with yr11 trig!
i have not gone to sleep yet
Have good night!
Help with my trig forum pls
when you, for the purposes of being tidy, need to remove the negative sign of the leading coefficient of a polynomial equation P(x)=0, do you generally think of it as multiplying by -1 or dividing by -1
idk
Prolly multiply but idk
The former but they're equivalent so your choice doesn't matter
is 'mathematician' a profession or is it just a title for people that do mathematics?
why are exponentiation and roots so weirdly defined for complex numbers
is there a rigorous definition of the "principal root"
If someone has an answer to this please also ping me
This might help I have no idea https://en.m.wiktionary.org/wiki/principal_root
Here it’s defined in C as a root which has the highest real part and positive imaginary part
It's an actual profession
it is both
Do i major in math, statistics or cybersecurity?
that settles it, definitely a bot
major in all 3
cybersecurity
maybe then you can figure out how to stop this hacker from occupying your account
clearly, your privacy is compromised here
history of late antiquity is a fascinating area and worth studying
real
I need all your thoughts. I’ve done my google search and stuff but I don’t know, I don’t somewhat find it helpful. I need all your help for this.
Im a mechanical engineering student. And currently I’m hating it. I wanted to do computer science but unfortunately due to my lack of hard work mechanical engineering was the degree I could get due to less competition. But I’m considering change my major through internal transfer.
But my choice is Mathematics. When it comes to mathematics I find it almost like computer science. It’s problem solving on the most part. U have a formula in maths, u have a code in cs and basically the more u practice on how to code like how to solve a math problem you learn through it. Like there is active learning in mathematics and computer science and I like that. But I hate engineering because of how much I need to remember and I’ve always disliked physics too. So I was hoping well could y’all suggest whether if you guys think it’s a good choice to move to mathematics from mechanical engineering?
you can (and tbh should) learn math while doing mechanical engineering
and consider that you're not going to be solving math problems as a job most likely
Political science
much like knowing how to code in some language as a cs student isn't enough to get a job
there's still an engineering aspect in cs in that you need to know how some specific technology works
Getting a job in programming is pretty much an act of shooting yourself in the foot
True. I was leaning toward banking with mathematics. Unfortunately my university does not allow me to take a Math Minor while I do mechanical engineering and plus I’m already struggling with the physics part. I’m doing great on the math side although I’ve only done easiest courses like Calculus I, II, III Linear Algebra, Statistics and PDE (including Fourier Series). Though I struggled in some of them I was able to take it as a motivating challenge unlike other engineering courses which is a lot of reading with physics along with memorization.
I also planned on maybe directing my career path towards Banking as a trader with mathematics. But from what you are saying, it’s made me indecisive.
May I ask, with your Postgraduate in Mathematics or with any lower tier degree in Mathematics, what do you do for living? Assuming u did Postgrad in Maths from your roles.
I didn't, I'm just running c++ saying hello world
idk why would you need anything more in terms of math than what you know to do something outside math research
i may be stupid but isnt there a simpler way to prove l'hopitals rule that doesnt use cauchy MVT
cant i just do
Prove it by linear approximation, although that's much more work than using cauchy's MVT
$\frac{\frac{(f(x+h) - f(x)}{h}}{\frac{g(x+h) - g(x)}{h}}$
Serphic
Serphic
i mean it'd be a huge pain in the ass to prove this with functions that have different variables huh
like w chain rule
is/are there any "complete" mathematics tutorials? Like that guides a person from high school level to preuni to uni to advanced/olypiads
I am a uni student but I feel like I have some extreme gaps in my knowledge


yeah but the reason i was confused is that we often say that sqrt(4) = 2 is correct and sqrt(4) = -2 is incorrect, so does the same apply to complex numbers
if yes then it would follow that $\sqrt[3]{i}\ne-i$
DiamondPanda16
I'll join the search with you.
Let's look at the cube roots of i. They are
sqrt(3)/2 + (1/2)i,
-sqrt(3)/2 + (1/2)i, and
0 - i.
According to the definition above, we pick the one with the biggest real part. That would be the root with sqrt(3)/2 as the real part.
If it was a tie we'd pick the one with the positive imaginary part. Real parts and imaginary parts are both real numbers, and the real numbers are totally ordered, so we can do this.
yeah it just feels a bit unnatural that although one of the roots is just -i, we still choose a more complex number as the "principal" root, but i guess it makes sense mathematically so its fine
This is just a subjective feeling that you have. You want the cube root to be easier to write out. To see why the definition above is better, let's look at something like the cube root of 0.001 + i. What do you think the cube root of this number should be?
is there a way to just see if a diophantine equation has solutions or not without iterating the variables?
like let x=97: x=k(4n+1)+3n?
wdym, what's the original problem you're trying to solve
I've been working with 6n+-1 and identifying patterns in the properties of n and whether a given n produces a prime or composite. it would be very beneficial to not have to iterate k,n for larger x.
it sort of sounds like you could have some simplification if you use the chinese remainder theorem but I'm not sure I understand the connection between 6n+-1 and x=k(4n+1)+3n or what you're iterating k and n over exactly, I assume you're trying to find positive integer solutions in k, n for every x?
oh, sorry, that was just an easy example.
For 6n+1
n = k(6i+1)+i where i and k are whole numbers
n = k(6i-1)+5i-1 where i and k are whole numbers
these two equations produce all of the composite numbers of the form 6n+1.
i also have a set of equations for 6n+5.
so having a way to test an x in place of n and determine if there are or are not integer solutions for the equation would quickly tell us if the x would produce a prime in 6n+1
using CRT can drastically reduce the search space i was just curious if anyone had a more direct method.
hmm I don't see how that works
can you show how you use those two equation to make a composite number of the form 6n+1 and show a proof of how it doesn't make primes
well lets say k=1 and i=1
1(6(1)+1)+1 = 8
6(8)+1 = 49 which is composite.
these equations were derived from observations i made from looking at n from 6n+1 and noticed periodic patterns in when n produced composites. specifically if n%5==4, or n%11==9, or n%17==14
hmm k=4 and i=1 makes the prime 29 4*(6*1+1)+1 = 29
oh I'm mistaken that's just hte n
right. so that plugged into 6n+1=175
I see how they work now
while not a proof i have checked these equations out to 10,000,000
the first one is when you take (6i+1)(6k+1) and expand it out to make 1+6n with n=k(6i+1)+i so it's composite by construction
I imagine the other one is pretty much the same thing with like (6i-1)(6k+5) or something to that effect
exactly
that proves they're composite by construction then
it proves the observation
well specifically they came from the observations when n is congruent
4mod5
1mod7
9mod11
2mod13
14mod17
and so on
then n produces composite.
well doesn't matter how you got it at this point, let me explain a bit more why
so when n == 4%5 and is plugged in to 6n+1 it will produce a multiple of 5
Take n = k(6i+1)+i and plug it in to 6n+1 and you get:
6k(6i+1)+6i+1
Notice (6i+1) appears multiplyin 1 if you look at it,
6k(6i+1)+1*(6i+1)
Now factor out the 6i+1
(6k+1)(6i+1)
This is composite unless i=0 or k=0
right.
another way to look at it is if
n%(6i+1) == i where i is a whole number
or
n%(6i-1) == 5i-1 where i is a whole number
then n produced a multiple of (6i+1) or (6i-1) respectively when plugged into 6n+1
anyway, with the equations here producing all composites of the form 6n+1, we can reform these to test whether a value x would produce a composite or a prime. for large values of x this gets computationally cumbersome. using modular reduction and CRT we can greatly reduce the search space. but if there were a method to just determine if there are integer solutions this would be a very quick primality test.
unfortunately it's not, the approach is basically equivalent to brute forcing every possible factorization of the form 1*1 and 5*5 mod 6
sorry I'm probably sounding like a wet blanket here
thats ok, I appreciate you taking the time to talk about it in general.
cool yeah have fun
thanks
yo can someone help me im stuck in a roblox game rn and idk this math question
4a+6b=10
2a-4b=12
what does 12a equal?
use noggin
whats a noggin bruh
4a-8b=24
please read #❓how-to-get-help
Hi
I have a problem
Which is how to be a mathematical thinker
Or how to approach a question
Many times i althouh i have the information and memorize i cant solve a question or think logically
I have some openings in question like when i see a fraction i should multiply it to get a whole number
Or taking a common factor
Or even breaking down question
But in many times i can't do that and i can't think logically althouh i solve alot questions
I think the problem is the way i think or that i can't understand and the learning in my country isnt good
It depend on memorizing more than understanding and deduction
Ah so how to deduce thats another point 😂
anyone have gce math past paper in 2023
Essentially, it all boils to practice and exposure
The more proofs you read, the more you are exposed to methods and common problem solving techniques, the better you get at coming up with stuff on your own
Although there are books on problem solving in math that you can refer, I personally never really picked one up, it were mostly my comp math skills that kinda helped me
Another suggestion for this is to be as lazy as possible when solving math problems. The more lazy you are, the more likely you are to come up with an elegant solution that solves the problem without much effort. Math is not a field that you can be good at in a day. Learning things takes time and experience to ground your intuition and curate your maturity in mathematics.
To be frank, I study probability for over the span of 7 years and understand almost nothing about it. I still need to look up the pmf of the geometric distribution or need to look at the real analysis and measure theory book for the definition of integrals.
I know this but the real problem is understanding basics in our school tell us cos 90 =0
But they dont tell us why i didn't understood alot of math basics
So now in my vaction I must search in books such as alg and trig 2e
Wow
And when i understand it well and where it come from its a very good felling
yeah. and this is also another problem: the more you learn, the more you realize that you know nothing.
As an arabic person i must search for knowledge in another videos
That right i felt that
In our countries we memorize the qurstion and its answer and with a new idea my brain is turned off😂😂
It took me 3 years to finally understand how to factorize polynomial, of which at that time it is already 3 years too late for the algebra test lol. But at least I am glad I understand it now.
in my country, it usually is the memorization too. and I am really bad at that
Same 😂
Great bro ❤️
like, you have to know sin(A+B) formula by heart. I don't. Good thing is, I realize that I can use my complex number knowledge to prove that in the exam hall. That was the time I felt like a genius.
It is like Eureka moment. That is what keeping me in the mathematics loop
Yeah that things that make me want to understood every single point of some basics
What you can do now is probably stop before using the formula. Stop and think one step back: can I do better? Is there a way I don't need to memorize anything other than the common knowledge?
The bad thing in our country that in last year of high school you must choose either to be a math student or a science student
So when you enter college you choose a math college or engineering
Thank bro ❤️
but math is science, at least usually associate with science department
I mean with science biology
yeah. math is one of the branch of science elsewhere
like, you can't do ecology (subfield of biology) without calculus...
I know but you either choose math or biology it decide what college you enter
weird. maybe if the current system where you are does not fit your needs, you can consider studying elsewhere. I know it is hard to do but consider it as one of the possible choice.
Yeah its hard but as you said make as a possible choice
Thank bro for your advice ❤️
What are some good resources to get prepared for calc 2. I just barely passed pre-calc W/ trig and calc 1. I kind of know how they work, but not on a level I am confident enough to explain or teach. I want to relearn trig and calc 1. My ultimate goal is to get my mechanical engineering degree. All your recommendations and help is much appreciated, I can't wait to get involved in this community more!
how does one overcome a lack of mathematical confidence
like, I passed with Bs from a relatively meh undergraduate institution. I got Bs in my first semester of graduate school, then dropped out.
as I recover from depression I'm wondering if the thought of me being genuinely just bad at math is true or not. I can't solve competition math, I looked up the solutions to homework, yet I passed exams. idk what exactly would give me the confidence/will to try and surmount my lack of math knowledge at this point, given that I don't rigorously know math
competition math is far removed from what is taught in university and what is done in math research
Discussion >>> Discussion 2
I assume that Calc 2 is integral, right? If you have no prior calculus experience (like, never took it during high school) then you can start from the traditional calculus textbook that you should have from Calc 1. Khanacademy is also a good place to start or AP Calculus BC materials can help you with this as it designed to be used on high school students.
Honestly, I would not be surprised if someone at the graduate level could not solve the competitive math problem. Those questions are designed to be puzzles, unlike what graduate students usually encounter, which requires a different mindset to solve. You know that competitive math has solutions, but your work in grad school might not even have a solution or a satisfying solution.
And B is not a bad grade.
You did get into the graduate school and that is one of the proof that you are capable of learning
What you have is called "imposter syndrome".
also you just don't learn the techniques for competition maths. on the extreme end most maths graduates dont learn euclidean geometry at all, much less be aware of what "pascal's theorem" or the "brocard point" is
and dont forget people regularly get <10 on the putnam. even then putnam is easier than competition maths.
How bonkers is it to try to switch to the math department? I'm a computer science phd, but I just feel the way math people are working on my problems is more interesting and efficient
Could I ask the question "How to learn math" in the math forum...
🙏
Hi I need some help with a flask web-app i am working on. it works, but i need it to print the image generated (successfully) by matplotlib on the webpage, and also there are a couple of minor issues, i need help with.
I'm a 23 y/o born without my left hand, and my right hand only has 3 fingers, so writing by hand is nearly impossible, so I have to do math on the computer. I used to have something called CX CAS when I was in school I think, but this thing seems to only be purchasable by schools, not private individuals, and I'm looking for a new software to do basically everything math-related, cause I can't write at all. I'm doing high school math, I guess you'd say, I'm Swedish and here I'm doing the equiv of high school math, is the best way to explain it, I think.
Any ideas would be greatly appreciated, I want to get started but it's very hard to find good info on programs, cause when you search for programs, usually you don't get programs to replace writing by hand, it's just ones for visual representation, etc.
if by "cx cas" you mean the ti nspire cx cas calculator, you can definitely purchase them as an individual, and i happen to own one myself
so, i'm not looking to buy a physical calc, it's the software version
it has the calculator in digital form, but also a ton of functionality in the software that allows just doing math in general
"TI-Nspire™ CX CAS Student Software"
ah, ok, i don't know much about that
my point though was that hey, maybe there's even a better software out there? Cause it wasn't the most convenient thing ever, but it worked
yeah its really hard to find out cause 99.9% of people can write by hand
there's mathematica, but i've never actually used it more than a couple of times, and it's also kind of a programming language, so idk if it will be that easy to use
if you just need to do charting and graphing, there's plenty of free tools like desmos that can do that very well
You can set up flask to serve certain directories for things like images. You would store the image in those directories and then generate html containing the path to the image in flask to serve it.
for me it isn't even complicated stuff, it's just things like linear equations, algebra, trig, etc
at an earlier high school level, again, so not anything crazy
maybe you could learn LaTeX for equations and then desmos for anything visual
What kind of math?
lots of people here take notes using LaTeX instead of handwritten notes
it was 5 years ago i did the last bit before this in school, and I'm only now looking through the course in swedish, so I can translate a little, but it seems like things like log, polynom, 2nd grade equations (correct translation?), trig, statistics (dunno to what extent)
I'll look it up thx
you can get started practicing it in #latex-testing and #latex-help
we have a bot here that renders latex: $ax^2+bx+c=0$
suremark MSC2020 60G40
thx i'll see, though as per usual the path of least resistence may be easiest, just think i found a way to circumvent the free trial thing so i may be able to just use the software im used to, dumb thing is im willing to buy it, it just isn't available
This problem is so annoying, i had the same issue with Cisco equipment -.-
Can someone explain me
What's relevance of 1st law of Newton since it can be derived from 2nd law easily
I have my interview on 13th😭
One could interpret the first law as actually being a definition for inertial frames
Ooooo like there is no reference of acceleration there that's why
How please enlighten me
F = ma, if a = 0 then F = 0
Like 2nd law says rate of change of momentum is directly proportional to force applied and 1st law says that body won't change its state of motion or rest unless external force is applied
So basically a body's momentum will change only if force is applied on it
Oh like that I see
Yeah sir
Clever
I hope just they don't ask me these kind of questions
They can ask worse
😭
Nah chill man gotta keep ur head cool at an interview
Be witty but idk if that works
Yeahhh I gonna try to do that lol
Yuppp
Honestly they'll be asking trick question to see how u would react to it
Yeahhhh most of times they do that only
guys in desmos
sin(x)
and sin(sin(x)) graphs are literally the same
is it supposed to be that way
cuz i cant comprehend it 😭
but they aren't ?
im writing it wrong prolly
no
Not without approval
@pulsar pagoda
Ok
yeah so what's your interest in digital signal processing? I've moved away from electrical engineering over the past few years so my practical advice is very rusty
Operational amplifiers
yes, they're wonderful!
truly beautiful devices
Yeah thing is I don't get any physics nor cálc in My major
what's your major
So i want to compensate for that cause im getting an offer for a Masters in ER
Ah, ok.
EE
Oh!
Software engineering
Like ive been pivoting to apostol calculus thats sort of introductory analysis (easier than rudin)
And i know basic LA
Sure, I see.
I Guess some electronics courses would be required like for analog electronic signals
But I have no idea where to start

Wait is your major not going to teach you electronics
i'm confused i thought you are an EE
Ah, I misunderstood
Well, do you want me to like, talk about the textbooks I read in school?
I am sure you could like, look up MIT open course ware and see what the textbooks they use in their classes are
Sure
I used "Electric Circuits" by Nilsson
and "Basic Engineering Circuit Analysis" by David Irwin and Mike Nelms
So i see both involve Fourier analysis, how is this different from lets say harmonic analysis? Is that just a math thing?
Also there is no differential equations course in my major but the 2 volumes from apostol give an introduction to it. Maybe ill pick something else if I feel the need
I did harmonic analysis through number theory. I think it just depends on what you want
More applied/pure
I Guess since it's EE applied would be My bet
the good old DFT
TIL that The difference between the nth triangular number and the nth square number is the (n-1)th triangular number
Kinda obvious if you think about it geometrically
Heyy f0xy sup
just try to ask i guess
ask in help chat room
thats what did
or you can try directly #math-discussion
Is $δ_{ijk}=δ_{(ij)k}$ or $δ_{ijk}=δ_{i(jk)}$?
luke1337
context?
luke1337
levi civita or something?
is basic mathematics by serge lang too time consuming for a foundations towards calculus physics? 94% of 1 section consumes me atleast 3 hours
W'Hospital
bro suvat on falling stuff doesnt make sense
usually you have 2 inputs
the generalized one is written differently
that's why
yea
because Seven murdered Six's family and friends which, quite frankly, was deserved.
hi higher!
hi Akira!
My final exam in like 4 days how can I memorize like 50 different formulas Im highsjcjool
how's you
okie dokie so far today 

sup chat
wazup
Hi
gay
the flag is disappointed in me 😭
it's because you delete too quickly

is this a slay moment? i cant tell
can a romantic relationship exist without sexual attraction
sure, I don't see why not
yea
im looking at dating guru advice and i dont want a relationship where i need to make the person think im more valuable than them
people will tell you it can, and it can, but its important to keep in mind that a relationship is healthy when it satisfies needs and desires of both people involved and oftentimes sexual attraction is a need someone is looking to satisfy from a relationship
so if that's not something that's present on your end, you had better communicate about whether or not its an expectation of the potential partner
and if it is, thats not a failing on their part
that doesnt sound like something you should have to do in any healthy relationship
in fact i would say making your partner feel like they arent as valuable as you is probably a recipe for disaster
I think your dating guru might be trying to tell you how to manipulate women
And not form a healthy relationship
my crush doesnt find me sexually attractive so i wanted to see if it was possible for us to date
well, romantic attraction has a pretty strong effect of making someone more sexually attractive
so i wouldnt really worry too much about that if they're interested in dating anyway
but if the problem is like "their sexuality doesnt match my gender" then i think that can be kind of a tougher hurdle
my point here being, that part of it might come with time
if you become good friends and a romantic attraction develops first
situation: I am high school male, she is high school female, I feel lonely after changing schools, she cares about me, I am considering trying to date, no conversation has happened
sorry if it seemed like i was in a relationship
yeah sure
i just mean like
as you become friends and that becomes more of a possibility
the sexual attraction could follow and its not really something you would force
Why I found this situation like an optimal stopping theorem problem? I think that theorem can be applied here
Joke aside, relationship... regardless of it being a mapping or real life, you need time.
time to understand it
move on
kind of silly
and dont always have it
true... that's why some people said winning love is like winning lottery
someone who truly loves you will love you the way you are
i dont believe they are the one for you
as hard as it may be
but the one takes time to find
unless theyre someone that just lacks sexual attraction in general
theres plenty of non sexual relationships thats okay
perhaps they r asexual? either way, if this is something that bothers you there is very little chance you can 'work around it' or 'change them' without becoming resentful or drained, it's good to know what you want
yessssw
hmm
yoo
anyone alive
is this a motivation channel??
it seems so by looking previous chats
nope.. only ded people alowed
sup
i think u r dumb
nah .. i a genius
u don't know how to manage worlds
yhh
cool
k .. but i have no pratice



