#serious-discussion
1 messages ¡ Page 510 of 1
it doesn't really change anything tbh
you learn how to do things in your head form just getting enough practice
like you do enough fraction problems on paper you'll learn how to do it without paper
If this was correct.
Then why is this?
if you learn how to do it in your head, then that wont translate to doing them on paper
I don't mix up concepts, I mess up numbers. đ
Lack of practice
That's backwards.
what do you mean by an "easy problem"
cause we all have different defintions of easy
That is fair enough. I guess for me an easy problem would be something from the exercises section of a calculus or below book.
Yeah, I would def not avoid paper for calc lol
x^2 +8x +6.
No paper, draw.
Draw as in gunslinging.
Not.
Paper drawing.
like i'd probably have trouble adding 2 fractions in my head, something like 1/13 + 1/11 would be kinda slow for me to do in my head
but like, give me a piece of paper and i can do it much faster
human beings don't have good RAM for math
and you very rarely need to do math in your head
Your RAM is as good as you've made it.
"Here's a random expression, give me the answer!" Lmao what.
I can do that, but like, I have to remember the equation in my head. I'd rather just write it down and not have to store information in my memory.
what are you even asking
For roots.
ok that's not obvious lol
I'm used to teaching Algebra.
why would you solve for roots in your head????
I mentally completed the square. 
Where it's usually implied that roots are the question.
hmm i don't like implicit questions tbh
There's WAY more questions you could ask about polynomials than just that.
it makes people think polynomials are a "question" rather than a mathematical object
But like, that's quite unnecessary to remember in my opinion. Why would I try to remember all the numbers when I can write it down? I'm not saying it's bad, I'm just saying I don't get why you'd do it when you could use paper. 
You're both right.
I feel like this is heavily dependent on what you're doing
I'm used to teaching secondary school Algebra, my bad.
like i get it, to an extent you need to learn to do some simple math in your head quickly
or else you're gonna spend forever doing arithmetic
like for a big proof if I'm not writing stuff down then I'll almost always be screwed over big time
but stuff like the quadratic equation is fine to write down
It's a bad habit to ask questions that way even in that level of algebra.
maybe for very basic algebraic manipulation and algorithms I can see the idea behind not writing down too much
I mean, whatever works works. If that's effective for you, then by all means, feel free to do it.
but just saying "don't write things down" in general feels quite disingenuous
I never really cared about the approach so long as there isn't any grave conceptual mistake.
ultimately though yeah just do whatever works for you
I feel like it gets harder the higher you go not to write it down.
I guess there's no shame in trying to work on mental math skills in general though.
I was able to do some integrals and most derivatives without paper, that was a while ago though.
Somebody can always give you a derivative you can't do in your head I guess.
Lots of nested quotient/product/chain rule applications just get out of hand lol.
It just tilts me a little bit when people can't do like 15^3 even if their life depended on it.
Because the thing is.
i don't think i can do 15^3 in my head 
I really hope youâre only talking about high school, where exams are the emphasis
I think it's because in order to do problems in your head, you have to get smart about it.
i'd have to do 225*15 on paper
It's not hard, watch.
It's not hard on paper...
Because at uni nobody really cares if you can do fast multiplication in your head
I'd be impressed for a couple secs lol
Same deal for integrals and derivatives
225*15 = (225*10 +225*5) = 2250 + 1000 + 125 = 3375.
it just doesn't seem worthwhile to learn a "trick" to do this when I can already do it pretty fast on paper ya know
like it's a cool trick but it doesn't seem very pracitcal
that's what i would do but just on paper
Itâs just a party trick really
You cheated by typing smh
the hard part is keeping track of all the different parts of the calculation
Admittedly I do think mathematicians are better at arithmetic than they pretend otherwise
Here's one for 87^2.
I think it depends on what you're studying too.
Yeah I guess
c^2 = (a+b)^2 for some selected values of a and b.
Let a be the tens' place and b be the ones' place.
but like my question is just why should i practice doing problems like this in my head, when i can do them on paper much faster with a much lower likelihood of errors?
I suppose thereâs no harm strictly speaking in learning these algorithms
like practicing getting rough estimates in your head makes sense
that's very useful
but if you need an exact answer use paper or a calculator
It can also teach you how to come up with algorithms on your own, and learn what makes an algorithm fast in the first place
yeah but you can still apply those algs on paper
(a^2 +2ab +b^2), a=80, b=7, 6400 + 1120 + 49 = 7569.
You might be better off working out whatever algo on paper first.
The point isn't to know the algorithms.
But emphasizing the use of the algorithm in manual computation over developing or comparing it to other algorithms feels rather pointless
yeah but you can do that with paper anyway no?
Right, which is what I was saying
what's so special about doing it on your head
You totally could, but you won't be motivated to.
How do you think a computer scientist works out a complicated algorithm?
And yeah you may as well just do it on paper
(It involves paper)
i use all these techniques myself and i always used paper 
I guess it depends on the person but it's usually not jusy "Imma do this in my head"
Yeah me too
I'm saying, doing it without paper will force you to discover (80+7)^2.
I suppose at the end of the day it depends a lot on what youâre working with
i don't see how it will honestly
I mean you could also brute-force it with the standard multiplication method
You can "discover" that with paper...
honestly to me it seems like you'd be less likely to
In your head?
paper is a much easier sandbox for messing with math
Fucking hard.
sure
it feels like to me doing shit on paper would make you better at doing it in your head better than exclusively trying to do everything without paper
Binomial theorem exists on paper there's no need to discover it in your head.
I could do normal multiplication in my head tbh
yeah if you didn't already know what (a+b)^2 expands to doing it in your head is needlessly difficult
but in general nothing wrong with writing it out
I don't know anybody else in person who can do synthetic division without a piece of paper, measuring against people who have just done like twenty synthetic division problems.
you learn the "trick" and formulas by messing with paper
and then apply them when you need to do shit in your head
Synthetic division is fast as fuck on paper lol.
it feels like you're more against rote learning in general tbh
what's synthetic division?
Actually, one guy.
do you mean long division
This.
It's this stupid fucking paper trick to do polynomial division.
but that's quite separate from doing it in your head versus writing things out on paper
i don't see why you can't avoid rote learning with paper
A variation of polynomial division for special cases.
No one who learns it actually knows why it works.
long division?
like trust me, I fill out like 50+ pages per week for my working out
yeah i never understood it until i learned polynomial division
but like in hindsight it's obvious as fuck
They literally teach polynomial division right before synthetic in almost every sane algebra course.
if I were to do all my math in my head it'd be a shitfest
This is really my complaint.
People don't know how it works because they're dumb and don't pay attention lol.
what the fuck is the left hand thing?
America.
that's not how we did long division
it's not really just america tbh, synthetic division is taught in quite a few places, and unfortunately as something that feels separate to polynomial division
I never got the point of synthetic division either. I get the idea, but like, it's not that much longer just to do polynomial long division.
It's just a convenient way to rearrange polynomial division when you wanna divide by polynomials of the form x-a.
it's good shorthand, kind of like how matrices are good shorthand for systems of linear equations
My sub-argument is that doing things without paper makes the situation so difficult that learning things by rote becomes untenable and so you have to get smart.
It's way faster for shit like factoring once you know the roots.
but ofc if you don't know why it's a good shorthand it's useless
Let me give you my anecdotal story.
I suppose I can sort of see your point now with this
or you could be like me and be so useless at memorizing stuff that you have to learn tricks just to be fast on paper 
it may be true to an extent, but eventually you will hit a brick wall if you do choose to continue further studies in math
I just try to understand the concept and the tricks come out naturally. 
Get asked division problem.
I don't remember what the numbers were, we'll say it was 60/3.
Realize that 60 is 3*20 and accidentally rediscover factoring.```
Something like this actually happened to me when I was, like, in elementary school or something.

s/discovered/discovered on paper/
how did you realize 60 was 3*20 tho
were you doing it in your head
Yeah. Could I do $\int_0^{\pi/6} \cos^2 \frac{x}{3} : dx$ without paper? I know the idea, just use the double angle identity. Do I want to simplify the absolute mess of arithmetic without paper? Hell no.
I wasn't using a piece of paper.
PhenomPlasma
I'm saying that sub argument is just silly and your example is also silly.
I just plug it into wolfram alpha
anyway the important thing abt math isn't how to solve problems
it's understanding concepts
You can jusy as easily discover those kinds of things with paper.
and understanding concepts without paper is needlessly difficult
But you're not forced to.
So who would.
also yeah, i think it's much easier with paper
i had another technique, can anyone pls remind me what are the parts of a division equation so i can explain
most people wouldn't bother learning tricks even if they couldn't use paper, they'd just try to memorize harder
Imagine trying to reduce a matrix without paper. 
Apply more pressure until memorization is completely impossible.
ok i got it
the reason kids don't bother puttting effort into deeply learning math isn't just because schools force rote learning on them, most kids just don't care to learn further than that
Who needs paper when you have electronic silicon?
Imagine doing anything without plugging it into a symbolic calculator
Me every day.
then they won't bother putting any effort in
like shit i remember memorizing the shit out of all my social studies classes cause i didn't care enough to understand the material
Finding Fourier series without a calculator is the worst. Practically everything is integrating by parts multiple times.
like sure maybe i could have tried harder to learn it, but i just could not give a shit at the time
I don't think I know any math major thay doesn't from time to time sit around doodling/writing/drawing to drum out some ideas/strategies to work out problems and junk.
i on the other hand tried understanding the material
and that was fun
in hindsight i should have tried harder
but like that's how kids are
they won't want to put effort into stuff they aren't interested in
Doing stuff in your head is good imo, just not to an exclusive extent.
don't torture them by taking away their paper 
just try to make it interesting for them
this lol
i hated social studies in 8th
Well, not exactly doing things in your head. I mean more like pondering and calculating a bit and junk.
and at the end of the year i read 4 books worht of material in 3 days for the exam
Hard to describe 
(it somehow worked)
I'm not saying to throw all the fucking paper out, I'm saying to try and avoid it as much as you can.
I also feel like doing things in your head becomes rather automatic too once you understand it well
but next year i became interested and did better
why would u want to avoid paper?
That sounds like a terrible idea lol
that does not sound like a good idea
I'll make one more comparison.
and to reiterate, that is an incredibly, incredibly bad idea for anyone doing uni math or higher
That's not most people.
But for what it's worth I managed to do single variable with basically no paper, I never tried to go past that so I don't know what happens.
Anyway.
One more comparison.
if you're dead set on using only your head for uni level math, or even first-year uni calc, good luck trying to do virtually anything
single variable calc?

this
people who are interested in math will do worse without paper, they'll have a harder time learning and understanding
and people who aren't interested in math won't put any effort either way
Single var calc can be super fucking trivial or incredibly complicated.
how can you do calc, something totally computational, without paper
If you were setting out to learn arithmetic, and you solved every problem with a calculator.
Depending on who's writing the problems.
maybe if you're some ultra supergenius like Euler or Gauss
You would learn no arithmetic.
I get what you're trying to do to make rote learning impossible, but at the same time, I do not feel like getting rid of paper is the solution. I agree the curriculum requires redesign, but like, not using paper is just handicapping yourself a lot of the time. So much of the time spent trying to figure out what went wrong can be avoided just by writing clearly.
If you were setting out to learn arithmetic, and you solved every problem with an abacus.
find the intergral of 1/ ln(x) 

But still not much.
I can teach you single var calc in a way where you can't just do it all in your head I promise lol.
and if u did on paper u would learn more
The handicap of calculation instruments extends in a straight line all the way down to paper.
aka analysis
This is the last thing I have.
Not even jusy analysis, you can just make problems way too convoluted.
i would keep adding the divisor to itself until it got higher than the dividend: (so for 60/3 3, 6, 12, 24, 48, 96), assign each of the resulting numbers a value ({[1]3, [2]6, [4]12, [8]24, [16]48, [32]96}), then subtract the largest number i could from the dividend, subtract the largest number i could from that result, etc, then add all the values of the numbers i subtracted (60-48=12, 12-12=0 , 16+4=20), then that would give me the result (60/3=20)
paper is a tool like anything else
if all you learn is symbol manipulation
then yeah, you haven't learned anything
but like, i think paper is the best enviornment to learn math
Don't rob yourself of the true pure joy of doodling cute animals for inspiration when you are stuck on hard problems.
it doesn't let you cheat, you can't do anything that's not coming from your brain
This is just an algebra question. Would you do this without paper? Am referring to mostly the second part.
literally all it does is increase your "ram"
I'm not saying you can't, but like how does doing this without paper help further your understanding. I don't get it.
i can do it, but it will take a while
but with paper, it would be much faster
I'd just use paper.
coz i can see my thoughts in a concrete form
This is cool.
My thoughts exactly. Why store everything in the brain when it can be written and ready for you when you need to refer to it? 
It took me a second to figure out why this works.
this is a tangent but i don't like that notation, just use f(x)g(x) or (fg)(x) smh
f(g(x)).
fg makes sense in certain contexts.
oh yeah that is honestly shit notation
This is from A levels. I actually think fg means composition here.
i think they meant like not f(x)g(x), as thats multiplication, but yeah lol
at least if you ask me
I agree it's bad notation.
this is kind of how long division works already,
Even for composition fg makes sense in certain situations.
wait is it supposed to be f(g(x))?
Like groups of permutations and shit.
(fg)(x) makes it clearer
I usually write $(f \circ g)(x)$.
PhenomPlasma
since as it is it could be either f(g(x)) or (fg)(x)
but is that f(g(x)) or g(f(x))
Well for ex cycle notation and multiplying cycles is literally function composition.
does this mean f applied to g, or apply f first, then apply g
g first then f.
well sure but I'm pretty sure that in this case they want one of composition or standard polynomial multiplication
and those are different
That's the common interpretation. The thing closest to x is applied first.
is function composition associative?
Yah in this context I agree that the notation is bad.
Yeh iirc
Pretty sure it's composition. A levels doesn't even teach adding and multiplying functions as far as I'm aware. And quite frankly I don't see the need for it to be taught either. It's just multiplying expressions.
i should learn proper LA
like i have been telling u to do for months
smh
Notation question.

yeah polynomial multiplication is really just distributivity
do it, and then teach me
If f(x) = 2x.
not much to teach specifically
Ez to verify (a o (b o c))(x) vs ((a o b) o c)(x).
Then f^-1(x) = x/2?
with taylor series, all function multiplication is distributivity 
Yes.
yes
Thank you.
i think
it is
hey guys what's $\sin^{-2}(x)$
Ninja
fg(x) = 4*(x^2+x+1), yeah?
since (f(f^-1(x)) and f^-1(f(x)) are both the identity functions
1/(sin(x)^2)
I know! It's called bad notation!

i actually like $\sin^{-1} x$ as notation tbh
Ninja
or sin(x)
I hate the $\sin^{- 1}$ notation. $\arcsin$ rules.
same
i think convention dictates it's $\frac{1}{\sin^2 x}$
i really like it
ah yes the U+2010 notation
thonk
sin^2(x)=sin(sin(x)) 
there we go
Or is it 2x^3 + x^2 +6x +3?
again, it could be someone saying (sin^-1(x))^2
I miss my alt codes.
Gives me nightmares.
Wait, wrong quote.
Was talking about the permutation groups one.
That stuff made me give up learning algebra for the first time. 
I remember it being weird at first but feeling kinda nifty after.
hey did any of you guys struggle to understand special functions at first
i remember trying to find the "formula" for sin when i learnt abt it
I struggled with hyperbolic functions for a while. 
But I think I was too young when I learnt the trig functions that I just accepted whatever, so I didn't have that struggle.
internally i think i thought sin x was just like a "name" for some "formula" of standard operations
i guess i ended up being kinda right since taylor series exist
but i don't think infinite polynomials would have satisfied me back then
There are certainly things I struggled to comprehend though.
there are things im currently struggling to comprehend
Namely how rearranging a conditionally convergent infinite series can change its value. 
I'm sure it is, but it just does not agree with my intuition at all.
it's like if you seperate it into positive and negative parts
they both go to infinity, and the terms approach 0
so you have infinite precision to work with, and you can get it to be any number
Fairly sure someone here has told me this before and I'm more convinced now, but I was certainly very confused.
lol was it in a vc?
Nah.
i rmb talking abt this to someone in vc
I think it might've been Namington who told me.
I used to talk about this a lot
it might be possible with javascript, youd just need to search each day and save the number
probably against TOS
that's why people make alt accounts đ
i wanna do it with this account tho
bold
$\frac{e^{ix} - e^{-ix}}{2i}$
nHail
yeah this woulda blown my mind back then
And also, I had the same questions. I never liked that there wasn't a good way to just compute the sine of a thing by hand
i mean, my problem was that i didn't understand what a function was at the time
that like you didn't need a "formula"
it was just some map from one set to another
This is why I dislike how functions are often introduced as formulas tbh
It took me a bit to understand that functions are just any sort of mapping
Welcome to Model Theory Wiki,the research encyclopedia of mathematical logic and universal algebra that anyone can edit.
This wiki will supplement Wikipedia's coverage of the subject. It is expected that Wikipedia policies will be applied here, with some important modifications:
Notability is evaluated with respect to the model theory community...
why
does this exist

Lmao
That's why people make IP bans ig
that's why vpns exist
whats abstract algebra?
the study of operations on sets
ok?
like
addition, multiplication, function composition
it finds common properties across different operations and generalises
for example
integers can be factorised, but many other structures (like polynomials) have similar properties to integers with addition and multiplication
so if you generalise things about integers to all structures with these properties you can learn more about them
because we already know a lot about integers but not as much about eg polynomials
abstract algebra is about groups, rings, and fields. groups are sets with a multiplication operation. rings are sets with a multiplication and addition operation. fields are rings where every nonzero element has a multiplicative inverse (so you can divide by stuff in fields)
i mean that's not everything
Those two spaces after the period bother me to no end
an example of a group is the set of all configurations of a rubiks cube. examples of rings are the set of all nxn matrices, the set of integers, the set of integers mod n, or the set of all polynomials. examples of fields are the rational numbers, the complex numbers, the real numbers, the set of integers mod p for p prime, the set of all rational functions (fractions of polynomials)... etc
so there are lots of natural examples of these objects beyond the basic sets of numbers
ryc thinks that it is standard to do that
"set"
you forgot to mention the operations
but just ends up annoying everyone
How can I Open a channel
No need to be pedantic when introducing someone to AA lol
abstract algebra is all about proving things about groups, rings, and fields (among other stuff: modules, vector spaces, categories, and so on) and seeing how they interact
Tell that to the books
the operations are all implicit 
u can introduce without mentioning operations
there's quite a need to be pedantic on this
because people always get it wrong

i would need to define the rubiks cube group operation i guess
yeah
wdym
the books i have read mostly all say that new students often say a group is "a set such that there exists an operation which is..."
that one is just "to multiply position x and position y, do the moves that take you from a solved cube to position x, except do them starting from position y"
just go to a channel in Math Help Available and type your question in one. If you want to see the full instructions on this look at #âhow-to-get-help
It is you bum
it is no standard
I think it's required
not in this universe
which would imply every set with at least 1 element is a group
its never required
and thats wrong? 
yes
how so?
a group is defined as a set with an operation
consider: the set of endomorphisms on a set
whats an endomorphism
function from something to itself
these don't form a group under composition
which is the only real operation you'll ever put with them
yes
they can form a group under something else
doesnt have to be composition
set itself isnt yes
but i would say there is nothing wrong with introducing people to AA like that
But u should mention operation asap
i think there is something wrong with that
because the entire point of AA is operations
ways of combining things
Automorphisms of a set 
yes but then again, when u introduce someone to analysis, its not wrong to say "calculus done rigorously", and not mention much about bounding anything
but like
bounding isn't the entire point of analysis
operations are the entire point of algebra
haha....
yeah i kind of agree with alison in the end
i mean i dont disagree lmao
but i dont find it particularly wrong to not instantly throw the word operation in someones face who isnt that familar with it
but i think there's a difference in how you approach this if you are introducing someone to abstract algebra pedagogically versus if you are just answering someone's question "what is abstract algebra"
i guess



i think you should at least give an indication like "integers with addition" instead of just "integers"
sure, thats better than just saying sets with operations
yeah
coz for people not well versed and mature with math
saying "sets with operations" is going into hardcore abstractness territory
sorry
no need to say sorry lol
I thought yâall were talking about Alcoholics Anonymous.
i don't think msny religious addiction management organisations are particularly interested in algebra lol
âAAâ.

It doesn't look very good

oh no
Wow
do we ping mods
Yeah no that's not the discord brilliance logo
i see that now
You can send it to modmail
Lmao
I think it's instant ban
send it to modmail yeah
You can send it to trust and safety
To get the person banned from Discord
Might be more effective
@warped carbon you are probably gonna get banned anyway but you should probably change your PFP for other servers
oh nevermind
<@&268886789983436800>
If Iâm going to be executed, I might as well make it worth my while.
Bravo.
?
u can still change ur pfp u know
Why have that on your pfp
Honestly don't remember.
nazi hat
Bite me.
see the pfp of RemembertheRoyals
I see.
it's not appropriate, please change it
gotem
oh well
I made a report on Discord
Depends on what was posted
Should be perma'd from Discord

If it's spam or the messages themselves are bad I do
what even is this
Nothing you want to know
Oh its the nazi pony whatwashername
yeah lmao
Is
bdsm thing
doesn't belong on this server
Oh are they famous
Is this person normally here?
so stupid
Arianne?
I assume on ALTs
swastika my little pony
swastika my little pony
?? I do not comprehend
anyway
Anyway yea

It's scary when the owner knows the person
as i suspected
Lmao
Not the person
?
As in they have a reputation
Its a chatacter that appears a lot on the internet
Oh I see
ohh
So the nazis take that as their public symbol?
Probably satire
It might not be
Pepper has active
it's probably fake satire
yas
I see
In Wolfenstein you know the game has anti nazi tendencies
I don't know about this character
Yeah no
sounds bad
It is
"tendencies" I think killing Nazis is bit more than tendencies
Anyway
What a week huh
every week sucks
one more week before easter break 
I think my weeks will suck all the way until September
one more week before proper revision time 
You guys get a break huh
gcses 
certificate of general secondary education?
How to get up from bed 
That's not what I mean when I say roll out
what were you talking about here
I don't know much analysis at all
Analysis is absolutely filled with inequalities
oh

That's true
this
starting from epsilon delta proofs (or even before that depending on how/where u do it from) , analysis goes on to be inequality spam
its a bit of a joke, that analysis is inequality spam and algebra is symbol spam
lol
yeah
isn't that epsilon-delta anyways, just for sequences
although even before that there's still a bunch of inequality stuff for like suprema and infima, or just some basic properties of R
Btw @devout nacelle if I can ask, what have you been doing to supplement the lack in uni course
Trying to stay ahead of the classes and learn some things beyond the curriculum but my own lack of learning discipline gets in the way.
So not all that much
Hahahahaha
gmod in masters program
Unreal
Are you looking at places besides Germany?
India/Germany at the moment, US if I can figure out the finances
That's probably going to be an issue regardless of the place you choose
Kinda not helpful that INR is so cheap
Well its pegged to be that way
Do you / are you doing any undergrad research stuff
Nothing so far, I bailed out on a couple of applications midway because I felt I needed more time to iron out an understanding of basic math
I might look into it next year
Or winters, if that's possible
@devout nacelle ur 2nd year?
Yes
do you mind pings manan?
No, as long as they're within reason
not really
maybe it's not that you don't want pings, you just don't want to be flooded
besides, it's better to be polite anyhow
monday my exam. ;_;
Will be my first time I am gonna have to do a proof in front of eyes. Hope I will manage the proof somehow.
Have you not done proofs on your homework?
I did, but like not with time pressure and infront of two people.
sounds stressful 
I think the examinators are very nice people regarding the protocols of earlier exams.
also hi quantum.
hi
Guys. anyone can recommend a software for graph visualisation ?
like graph theory graphs (vertices, edges)
thanks
Oh my god guys I solved the bofa conjecture
oh my god i solved the ligma postulate
it's a joke

uhhh i think the original guy was making a joke too but not sure
or or alshfik was making a joke
and i got wooshed
anyways this is the wrong channel
bertrand's postulate is the only poorly named theorem i know
it is, isn't it?
it's archaic though
kinda like how we call it the riemann hypothesis
when conjecture is the more accurate term
even though i think both are technically fine
there's also the continuum hypothesis
that kinda thing happens with older math
since there's some reason to think that the riemann hypothesis is true
words and customs change with the years
i think that's the term >.> could be wrong tho
Any Excel/Google pros able to find a good video guide for this?
I wouldn't mind just a quick walkthrough either I guess
The tasks aren't hard really
I just can't read or understand them
I've been speaking and reading English for slightly less than 21 years but I really don't get it lol
Even did the little training module for this kinda stuff but when applied the format is different
Screw theory:
- https://en.wikipedia.org/wiki/Screw_theory
One may note that force is not even a normal vector! It is actually something known as a bound vector.
The point about Angular velocity:
why did he choose this thumbnail
LOL
legit once the video starts there is no bunny girl
its just the thumbnail for some reason
lmfao
mathematician's version of clickbait
I want an anime girl to explain Stokes theorem to me so bad
Its unreal
trivial
how do you even find this? literally 46 views :/
yt rec

wadaf lol
Me when I open the stacks project
Or nLab
nLab is tutorial hell even more than stacks project
you didn't like my awful joke? classic are slash woosh moment
is there a set-theoretic term for a many-to-one function?
i don't think i've seen the classification "many-to-one" outside of highschool
noninjective
Injectiven't. Please don't kill me.
Arithmetic is Easy're
now i feel stupid
its not a function set-theoretically
One to many is not a function.
yeah
since functions are defined as relations, where for every element in dom F, there is only one y such that xFy
Many to one is just noninjective
Well!
PhD
anyone familiar with arm assembly
You want to assemble an arm? 
yes.
who dis
why?
I just wanted some feedback on multiplying two ieee754 numbers in arm, I am at the point where I need to multiply the mantissas and I don't know how to go about it
considering the values are 24 bits and the registers are 32 bit, I am having issues storing all of the numbers in the product
wondering if there was a way to store some in other registers idk
Well,You are missing the point of IEEE 754
You just ditch parts of mantissa
@maiden lily
i know i was gonna do it after but if there is a way for me to do it without that thatll be good
like multiply the top bits of the multiplier/multiplicand
Well why do you think 0.1+0.2=0.3000000004 memes exist
i guess i could right shift the values 16 times and then multiply accordingly
Also are you designing an instruction or something?
that way itll hold in 32 bits
designing an instruction? no
i just have the values in two registers, i want to store the product in another register
I study partial multivalued functions sometimes
what does that mean emma
I am guessing like Non Deterministic Finite Automata in Automats theory
For example, consider the problem "closed choice on [0,1]". This means that given a closed subset of [0,1] you want to pick a point from it (so you want a function f from the set of closed sets in [0,1] to [0,1] with f(C)\in C). We can phrase this as a realizer for a partial multivalued function from closed sets to [0,1], namely the partial multivalued function G which maps C to C. Then a realizer for that partial multivalued function means a partial function f with f(C)\in G(C)
So you can phrase a lot of problems in terms of these partial multivalued functions
i feel like i lack the prerequisite knowledge for this
Here's a nicer way of saying this
So let's say you have a theorem of the form "for any X, there exists Y with Z property". Then you can turn that into a partial multivalued function by saying "map X to the set of all possible Y with Z property"
And then a realizer for that theorem means an actual selection of some Y for each X
So this is a way of turning theorems into sets
oh i see
that makes sense
The most debated question right now
Voiceover by @Charlie Hopkinson
Grandayy plushie âş https://youtooz.com/products/grandayy-plush-1ft
Grandayy vinyl figure âş https://youtooz.com/products/grandayy
Become a Channel Member to support me! âş https://www.youtube.com/channel/UCa6TeYZ2DlueFRne5DyAnyg/join
Twitter âş https://twitter.com/g...
Wsg cuh
is this p_i, p_j, p_f, or p_1
kk yeah that's what i thought too just making sure
yeah
but p_1 wouldnt make sense imo
yup wouldn't make sense
Poo
what is up
i came up with a cool question
until it gets brutally debunked by someone here
basically in statistics why is it valid to apply logarithm to the data
why stop at logarithm
so when you plot log(x1), ..., log(x_n) against log(y_1), ..., log(y_10)
you get a good correlation (lets say you do)
but what if given arbitrary data
i can find a function that allows you to correlate it đš
and then any old data would have some "correlation" because i can transform the data however i like
that is the principle behind machine learning, or rather statistical learning
but finding that function (or rather, space of functions) is potentially arbitrarily challenging
#TurnsOutIHadAValidMathematicalThought
There is of course no single function that can be used to correlate all data. But you can still seek more general functions that can be used to fit data sets.
@near fox what's wrong with using f(x) = 1
then all the data is perfectly correlated
i think you'd have to say something about "information loss" (i.e. you want a bijection)
But isn't that still an arbitrary decision to not want information loss?
- cool
- feels like a "standard" curve
- bijection
sorry wdym?
as in you'd want to use something that classifies as a transformation of random variables?
There is nothing wrong with it, but you don't get anything interesting. Indeed, the point of machine learning is to seek mappings that represent your data in some (ideally) low complexity way
tbh I don't know or care a lot about stats so I'm going to step out
But with f constant then eliminated all the informational complexity
how is "low complexity" defined, is it somewhat arbitrary
yeah there would be, but a lot of the time
There are various ways to measure it. There is kolmogorov complexity but it's nearly impossible to compute
kolmogorov complexity isn't nearly impossible, it is impossible
Yeah i see
if you could compute kolmogorov complexity you could solve the halting problem
damn
so if you can approximate the kolmogorov complexity can you approximate the halting problem?
but you can't computably approximate the halting problem (in the sense of computing the N for a given epsilon)
In general yes, but for a specific string it is still possible sometimes to calculate its Kolmogorov complexity
how enjoyable do you two personally find ML
That doesn't seem plausible to me except maybe in some incredibly trivial cases
i still havent gotten round to learning it
but idk ML kinda looks like a cool concept but quite boring to actually apply and use
so all of statistics
i was just wondering if you guys agree with that
It looks like a lot of fun I guess, a lot of my friends do ML but I don't really pay attention to what they do

I can only think of trivial cases too, but that goes to show that it is possible, even if no Turing machine can compute it for an arbitrary string
but all the hard work gets done by the AI itself
No I think that's a bad take. I think there are a very small finite number of strings possibly that can be computed, but that should be dependent on your definition of kolmogorov complexity, and different definitions of kolmogorov complexity give you different strings whose kolmogorov complexity can be computed
By definition of kolmogorov complexity I mean the universal Turing machine you are fixing to define kt
Lots of possible choices there
I'll take your word for it I suppose. It just seems to me it is possible to brute force compute it for, say, a 2 bit string
I think you have to consider the definition of kolmogorov complexity
Like I think you can design your universal Turing machine to make any finite number of strings have Computable kolmogorov complexity
But that's not that interesting imo
Sure. In the context of analyzing data, we might just be interested in a single numerical value.
And from my pov I care more about asymptomatics for kolmogorov complexity, so this sort of finite stuff comes out in the wash
There is no universal way to compute definite integrals either, but nonetheless a technique exists to compute one such integral
I actually really don't know how people use kolmogorov complexity in practice, I've only really used it for algorithmic randomness
Yo how good is ML at computing integrals đ
There is a universal way to compute a definite integral lol
is that just wolfram alpha
yeah my awesome questions are always unanswerable, what can i say.
There are, vaguely, ways to "learn" to estimate integrals from data, but I would not call it machine learning
I think the issue here is merely semantic. By compute I do not mean anything related to Turing machines that can handle general input.
I think the notion of compute you're using isn't really well defined from my pov
But anyway I'm going to sleep
Let's not use the word compute since it does have semantic meaning. I just mean, can I find the value for certain strings
Either way, this tangent is only to qualify my statement "nearly impossible" đ
In the context of ML, there are simpler forms of complexity. At its simplest, we might speak of just vector space dimension
One might find that your data can be projected into a linear subspace of lower dimension than when you started
rudin is looking pretty appealing for single variable analysis currently, but i heard that chapters 9 and 10 werenât very good. would it be ok for me to do chapters 1-8 and chapter 11, skipping 9 and 10?
or would there be some information in chapters 9 and 10 needed for 11
asking because i have absolutely no clue
although now that i think about it i would guess that it would be fine
yeah some of the later chapters aren't very good
imo skip everything after the chapter on special functions
so skip the chapters on differential forms and the chapter on basic measure theory
Rudin does quite a poor job with both of these topics
is 11 very bad?
for differential forms and integration you might benefit from reading the first chapter of Bott-Tu, and for measure theory you might benefit from reading the first 100 pages or so of Stein-Shakarchi
just use apostol quantum, smh
ok one more question, after finishing LA and reading rudin or a book similar to it, i plan on reading munkresâ analysis on manifolds. is there anything else i should do before that, or is what i just said good enough?
iâm aware i might be planning a bit far ahead
Hello !
since that book is essentially MVC with proofs I think that's a reasonable plan
ok thanks
well, proof-y mvc plus some intro differential geometry which still requires some analysis and linalg only
because iâm curious, specifically what parts are intro differential geometry?
differential forms?
that I guess
i guess manifolds too
yeah
it's in the title lol
I've only skimmed it but the book probably does all over R^n and then uses that to carry over to manifolds
also, iâll probably only read rudin up to chapter 8
that plan still sounds fine then right?
yeah
ok thanks
these are like the only important chapters in rudin
covering your typical (honors?) analysis in R
what is the most complicated type of differential equation
I saw these quasilinear PDEs
does it get worse???
nonlinear system of PDE would have the least structure, at least if the nonlinearity is allowed to be arbitrary, meaning you'd have very little information to use to study it
nonlinear stochastic PDEs 
Nonlinear PDEs in noncommutative variables 
pain
just proved that trace is sum of eigenvalues đ
nobody asked
What is trace
sum of diagonal entries of a square matrix
I c
would've been super funny if you answered "sum of eigenvalues"
The only proof that is coming to mind is using the characteristic polynomial
watch rice man is gonna do it now
I don't like that proof
aw
I'm trying to think
I thought he was going to
oh
thinking is for casuals
I often don't think before I act or speak
and thats how I lose friends all the time
darn you
i just used properties of trace and that the eigenvalues of a triangular matrix are the diagonals
i used trace(B+C) = trace(B)+trace(C)
I see
and decomposed a matrix A into a triangular matrix B and a matrix C with all diagonals 0
Yes
unexpectedly simple proof
i have regrets
and how do you check that the sum of the eigenvalues of B are the same as the sum of the eigenvalues of A?
The Fractalogist
lmfao
At the job fair at my uni today pretty tame to be honest
Also why do people associate Mathematics with Business they have nothign to do with each other
is a math tutor there to help you self study math
like...often i simply don't get math and need a problem explain to me
well if it's just specific problems then
ask on this server
if you like don't understand the material in general then get a math tutr
holy shit i've been skipping on the original harder better faster stronger cuz i thought the beat was a bit annoying but omg the two minute mark
quantum ur working through ladw right
yes
how do you like it?
i just started it
and its pretty nice so far
how long do u think it'll take to finish it
itâs good so far
i donât really know how long it would take to finish
maybe 3 months
if youâre rushing you can go faster
but i suggest going through each section in a way that at the end of the section, you understand almost everything
yeah
you wonât instantly understand everything
im trying to do every exercise
you probably shouldnât
i mean theres only like 5 at the end of each section
say, quantum, wdyt of Linear Algebra and its Applications
i donât know anything about any books other than book of proof any ladw
plus i havenât heard of that book
dang
can anyone help with my hw please
Guys please tell if Time Dilation comes in Einstein law of relativity?
How long would it take to self-study a book like Basic Algebra I
by who
if you're talking abt knapp's then after glancing at the pdf i can confidently say a long time
đ
Jacobson
What can I do with a math degree that involves helping others?
I guess become a teacher or prof?

