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[math]/\mathfrak{mg}/[/math]

Platonic universe edition
Talk maths, formerly >>16187402
>>
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>>
first for number theory
>>
>cardinal arithmetic
>ordinal arithmetic
>transfinite induction and recursion
>NBG set theory
>type theory
>surreal numbers

Are these concepts useful/do these concepts commonly arise in the context of (other) modern mathematics research (say, on algebraic topology or ergodic theory)? Or is it all just metamathematical ramble/computational nerd shit
>>
I'm gonna graduate at 30 am I cooked
>>
>>16240545
>is it all just metamathematical ramble/computational nerd shit
yes
>>
>>16240545
Cardinals and ordinals sometimes appear as examples or counterexamples in topology. Type theory had its revival by being combined with topology to homotopy type theory ten years ago.
>>
>>16240588
i got my first job at 31 lol
>>
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I'm trying to understand why we get the signs in the boundary homomorhpishm in simplicial homology:
[math]
\partial([v_0, ..., v_n]) = \sum_k (-1)^k [v_0, ..., \hat{v_k}, ..., v_n]
[/math]
hatcher says that these signs count the induced orientation on the kth face of the standard n simplex and that this is just obvious.
why is it obvious that the face we get when we remove the kth vertex inherits the orientation corresponding to [math](-1)^k[/math]?

What is rigourously even meant by orientation here?
I've been trying to make it more precise by thinking of a simplice as a convex subset of a certain affine subspace of [math]R^m[/math],
which through the ordering of the vertices get an ordering of the vectors spanning it but this approach turned messy.
I also had the faint hope that the boundary homomorphism would be uniquely defined by the property that
[math]\partial_n \circ \partial_{n-1} = 0[/math] and [math]\partial_1([v_0, v_1]) = [v_1] - [v_0][/math]
as I understand why we want these properties when we're trying to algebraically count holes of various dimensions (the motivation behind homology?).
but this fails to uniquely define a homomorphism...
>>
>>16240545
surreal numbers are useful in combinatorial game theory, which is probably one of the furthest fields from metamathematical ramble. the other stuff shows up on occasion but only at a low level. last week i was doing some homological algebra and needed some ordinal arithmetic to construct one of the counterexamples. in general if you don't enjoy them don't bother learning though.
>>
>>16240472
What actually compelled Kepler to believe this was the case? He was a smart guy but this was pretty batshit
>>
>>16241271
i thought this was like the ancient greeks, not kepler. the ancient greeks had some great ideas but a lot of it is batshit insane. idk how they came up with it i think they just had no clue so they made shit up.
>>
>>16241294
Part of the reason that it took so long to move away from the idea of epicycles was because it was inconceivable that heavenly bodies could move in anything other than a perfect circle.
These ideas lasted until very recently, all things considered
>>
>>16241297
yeah i mean it took thousands of years until people thought "maybe aristotle was full of shit and just made all this up" so i wouldn't doubt it
>>
Can i get some measure theory books recommendations. Not just the wich but the why.
>>
>>16241363
measure theory is pseudoscience
>>
>>16241297
>>16241305
It had much more to do with the invention of telescopes that enabled more precise measurements to be made.
>>
>>16241271
>What actually compelled Kepler to believe this was the case? He was a smart guy but this was pretty batshit
Not at all, actually. There were only 6 known planets at the time, so it made sense to correlate them with the platonic solids. His model also closely adhered to the known planetary distance measurements. Finally, it wasn't understood that objects could follow orbits by only a central force; it was assumed that there must be an attractive force and an opposing force (just how there is for electron orbits, hint hint) and the natural shape that two opposing forces creates is a platonic solid. Kepler was a smart dude.
>>
>>16241363
folland is great. it also just so happens to be what my school uses
>>
>>16241421
There's only five, but no worries... not everyone can be Kepler caliber.
>>
>>16241421
this is literally what the ancient greeks did. plato mocks it (or maybe he's just that stupid) in the republic [587b - 588a].
>>16241427
kek
>>
>>16241410
>6 planets
>5 platonic solids
>woah… these le numbers are, like, kinda similar??? I have a theory!!!!
>>
>>16241433
If we weren't on this Mongolian grasshopper board I'd think you must be a woman
>>
>>16240472
How old were you when you realized that the Microsoft Equation Editor is good enough for 99% of the times you would othewise tinkertranny with a hodge podge of various LaTeX modes?

Not only does Word let you enter Latex syntax, you can use the faster Unicode form.
>>
>>16240545
>useful
if you come into maths with that outlook for existence then you have the wrong disposition
>>
>>16240527
lol applied computer science fail
>>
>>16241233
>What is rigourously even meant by orientation here?
You know how in computer graphics if you specify three vertices in order, a triangle appears, but only from one side? And if you swap two vertices in the order, the triangle switches the way it's facing?
That exactly corresponds to what's meant by orientation here. The induced orientation is the order in which to specify the vertices so all the faces of the simplex are visible from the outside.
The way you can do that is by rotation. Define a_k = [v_0,..,v_k-1, v_k+1,...., v_n], and suppose you take a_0 as one of the faces as a convention. You want to obtain a_(k+1) from that of a_(k) (starting with v_0), by rotating the vectors v_0,...., v_n. Clearly you do that by a linear map that moves swaps v_k with v_(k+1) and leaves the other vertices untouched. This matrix has determinant -1, therefore it reverses the orientation, therefore you multiply by -1 to account for it so that the orientation stays the same.
>>
>>16241233
It is just a consequence of wanting del^2 = 0

You can do things purely symbolically to arrive at the properties without any simplex "story".
Let d be the operator defined by dv = 1 - vd, d(const)=(const)d.
Applying this to a sequence s=(v0)(v1)...(vn) and then pushing d to the right does what you want.
ds = (something1)[s] + (something2)[s]d
dv = 1-vd
ddv = d(1-vd) = d - (1-vd)d = vdd
dds = sdd
Clearly (something1)^2 = 0,
(something1)(something2) + (something2)(something1) = 0,
(something2)^2 = Id.
call (something1) del

d(v0) = 1 - (v0)d
d(v0)(v1) = (v1) - (v0)d(v1) = (v1) - (v0) + (v0)(v1)d
d(v0)(v1)(v2) = (v1)(v2) - (v0)(v2) + (v0)(v1) - (v0)(v1)(v2)d
Etc.
d(v0)(v1)(v2)...(vn) = del[v0,...,vn] - (-1)^n*(v0)(v1)(v2)...(vn)d

d is very similar to the usual differential operator, D, satisfying Df = f' + fD. The minus sign in d gives a kind of alternating product rule which makes the (del)^2 = 0 work.

Probably not the kind of answer you want but it is what it is.
You can use this to generalize del to get del_k satisfying (del_k)^k = 0 by requiring dv = 1 + v*exp(2*pi*i/k)d.
>>
I need to create a rectangle of X square feet with an aspect ratio of Y. Help a dumb engineer out.
>>
>>16241910
[math]
width := \sqrt{X Y}, height := \sqrt{\frac{X}{Y}}
[/math]

Assuming positive X, Y.
>>
>>16241936
Thanks homie, I’d hire you any day.
>>
>>16241765
what is d? it acts on what and results in what? what is v? what is a sequence?

the general setting I'm thinking about is a free abelian group [math]C_n[/math] with a basis a set of n simplices, and then we're interested in obtaining a boundary homomorphism
[math]\partial_n : C_n \to C_{n-1}[/math]

I fail to see how any of what you wrote makes any sense in this context
>>
What are some nice math communities where people study together?
I want to find study groups.
>>
Any anons know of a good youtube series that gets you up to speed on stuff like calculus and matrix/vector multiplication? I'm trying to get into electronics and programming as a hobby and I'm running into shit that I haven't studied since high school.
>>
>>16242071
try khan academy?
>>
>>16242071
Why does it have to be youtube? There's good books for that.
>>
>>16241363
I also back folland.
>>
>>16241953
d acts on the terms v0, v1, ... that are "multiplied" together similar to how the differentiation operator acts on functions.
The monomials you get correspond to your [] terms (assuming the v's don't commute)
For the usual derivative operator,
Df = f'+fD
Dfg = (f'+fD)g = f'g + fg' + fgD
This is how multiplying works for differential operators in the usual sense (evaluation of D remains pending).
The simple rule Df=f'+fD reproduces the product rule.
I used d as modified version of D.
It is basically related to Weyl algebra. You have dx+xd = 1 instead of Dx-xD=1 in the weyl case.
It is a bit different since Weyl algebras have {Di} and {xi} and [Di,xj] = kronecker(i,j), [Di,Dj]=0, [xi,xj]=0
I am only using 1 d and many v where d(vi) + (vi)d = 1 and vi do not commute (technically you could allow the vi to anticommute for your case).
Just think of d as acting on the term (v0)...(vn) where the decision branches for each factor that is encountered by d from the left.
For dv = 1 - vd, think of the the 1 as the action of removing v and the -vd as skipping past v and picking up a factor of (-1).

I told you this is purely mechanical and has nothing to do with the simplex "story". My point is this is the only way to get something that behaves like your boundary operator "del" and the alternating signs are just necessary to get del^2 = 0.
>>
>>16242163
My whole motivation was just to have some operator give ddv = vdd for each variable v since this would give a del that satisfies del^2 = 0 and operates on things of any dimension.
Since del returns objects of 1 dimension less, d must behave like dv = A+B*vd
This gives ddv = (A+BA)d + BBvdd.
For ddv to equal vdd, B must be -1. This B = -1 explains why removing vk has a factor of (-1)^k.
The value of A doesn't really matter (besides not being 0) since A^k will just keep track of how many times the dimension is reduced which is redundant since the number of terms in the monomials also keep track of this.
You can conclude
d(v0)(v1)...(vn) = A*del[v0,...,vn] + (something)d without even computing anything.
>>
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>2015: took calc 1
>got sick and almost died
>2015 summer: took calc 1 again
>2015 fall: took calc 2
>got a biz degree in sucking boomer dicks and getting meme'd on
>2024: taking calc 2 again going back for engineering and math minor
>have collected a full library of recreational mathematics by now
>the only thing I know is I need to know linear algebra, data structures & algorithms to become gigaChad
Feels chud, homers enemy
>>
>tfw I could have avoided a decade of pain if I had listened to my highschool nerd friends instead of my boomer barons
>>
When did you realize math was for you?
For me it was Calc 2 seeing the Fast Fourier transform and being gatekept from the hyperbolic functions. It was the first time I felt like I invented math AND I stood on the shoulders of giants.
>>
>>16242122
I'll give it a shot, thanks.

>>16242135
Because I don't need a book's worth of knowledge, just the cliff notes.
>>
>>16241971
My university has quite a few if you can put up with the REDDIT AURA. They have a "Geeks with Beers" Saturday meet up at a bar. No classy people in sight. So much blight. It always ends in a Discord detour. It's hard because I want to be genuinely friendly instead of social credit NPC script. So many of my personal projects have become dusty beyond my own grasp. People come and go. Americans are hard to host and harder to invite and even harder to keep around. I have kept much foreign company. Chinese, Saudi, Russian guests. When you meet someone super good they tend to travel a lot. I wish we had tea time.
>>
>>16242246
How?
>>
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>>16242264
My nerd friends did AP Calc in highschool, CAD, and so many AP classes they basically did 95% of their associates degree in highschool. I met homeschool kids who straight after middle school did their associates.
During HS I saw some rich kids "social skill" their way to the big bucks and thought shmoozing with them would give me such an opportunity. It failed. I sandbagged academia for the sake of desperate temporary grifts that were never enough. Those nerds never got gfs, never partied, never rubbed shoulders with big wigs, but they got out of school early and got the best jobs while the world was more upside down than we could have imagined. Those friends were like the big doge. Boyscouts. Based even. In the mean time I shagged my way to the Prodigal Son's shame.
>>
>>16242163
>>16242208
it looks like you're trying to say something programming language theory parsing related, but you're unable to make it precise, comprehensible or connect it to the general situation of sequences of free abelian groups and homomorphisms between them such that any composition becomes 0.
>>
>>16242250
when i watched the 3blue1brown "the hardest problem on the hardest test" and realized "hey this math shit is cool".
>>
>>16242576
>something programming language theory parsing related
Df=f'+fD is just Weyl algebra. It is how big boys multiply differential operators beyond the baby ones in diffeq with constant coefficients.
I constructed d from the free algebra R<v0, v1,...vn,d> modulo the ideal generated by all of the d(vi) + (vi)d -1 = 0.

Each monomial corresponds to your [] cycles in the obvious way if there are no repeats.
You just add multiply, distribute the way you normally would.

>connect it to the general situation of sequences of free abelian groups
I am defining the boudary operator since that is what was required.
There was a bunch of WHY questions about del. I am answering the why question by getting at something more abstract but arguably more illuminating (since you can cook up what del must be just from the specification del^2 = 0 which would be a nightmare if you just stayed in the "simplex" story).
I handed you del and its recipe. You figure out how it can be used.

I've noticed you haven't opined on how the simple rule dv = 1 - vd gives the correct answer for del for all dimensions.
Maybe start there.
>>
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>>16242654
as I stated in my original post it is in fact wrong that as you said [math]\partial[/math] is uniquely defined by
[math]\partial_n \circ \partial_{n+1} = 0[/math] and [math]\partial_1 \left( [v_0, v_1] \right) = [v_1] - [v_0] [/math].
Since already for n = 2 we can define
[math]\partial_{2} [v_0, v_1, v_2] = -[v_1, v_2] + [v_0, v_2] - [v_1, v_2][/math].
Here we have the signs being the opposite of what they are in the usual definition. and yet [math]\partial_1 \circ \partial_2 = 0[/math], as well [math]\partial_2 \circ \partial_3 = 0[/math], with the usual [math]\partial_3[/math]!

Thus we have choices as to how we actually define [math]\partial_n[/math] for arbitrary n. what I was interested in was whether there is a compelling reason for why the definition of the boundary homomorphism looks EXACTLY like it does for arbitrary n. not why is it an alternating sum, or any other question. such a justification could be along geometric lines in a way that clearly justifies it for general n simplices. or it could be along algebraic lines. but as I just showed we can in fact not provide such an algebraic justification for the two minimal reasonable requirements. since we can specially define [math]\partial_2[/math] with the opposite signs as usual and everything still works out!

from more research I'm settling on the conclusion that the exact form of the boundary homomorphism is defined the way it is simply because it 1. confirms to our geometric conventions in low dimensions, 2. because it's a convenient formula and 3. because it does confirm to the requirement that [math]\partial_{n} \circ \partial_{n+1} = 0[/math].
this is somewhat disappointing.

beside all that, your language and notation isn't well defined.
dv = 1 - vd is not a well defined expression in this context.
>d acts on the terms v0, v1, ... that are "multiplied" together similar to how the differentiation operator acts on functions
this is of course nonsense without more precisely specifying.
>>
>>16242250
Calc 3 when I accidentally found a formula for the volume of a pyramid during an exam
>>
>>16242846
>Thus we have choices as to how we actually define
Obviously you can just multiply my del by arbitrary constants c_n to get your "choices" of del_n since it is linear.
That isn't interesting. The ratios of the constants multiplying the "faces" remains the same.
>this is of course nonsense without more precisely specifying.
I worked examples.
Start with the monomial (v0)(v1)...(vn) where the vi don't commute.
multiply by d
d(v0)(v1)...v(n)
= (1-(v0)d)(v1)(v2)...(vn)
distribute in the usual sense
=(v1)(v2)...(vn) - (v0)d(v1)(v2)...(vn)
= (v1)(v2)...(vn) - (v0)(v2)(v3)...(vn) + (v0)(v1)d(v2)(v3)...(vn)
...
=del[v0,...,vn] - (-1)^n * (v0)...(vn)d

You might think this is just programming language or parsing but this is just how things are when you modulo things in algebra. You still retain the richness of the ring structure so it isn't just simply string rewriting.
I encourage you to at least look into weyl algebra (since I assume you know basic calculus) to even understand the flavor of what is going on.
Weyl algebra is useful because sometimes you can recast your problem in terms of the mechanics of differential operators then use analysis techniques to approximate the answer when a closed form is not available.
I'm surprised you are learning abstract math yet are so opposed to me taking your problem and abstracting it then recasting it in a different form to get the answer easily.
Better not look at how laplace/fourier transforms are used to turn differential equations into algebraic equations.
God forbid you look into generating functions and see functions that you never plug in a value for the variable but still add and multiply them to do combinatorial operations with the coefficients.

I solved your problem and a whole family of generalizations with some slick abstract algebra which I think is pretty cool.
Please tell me how you would find an operator del with the property del^k = 0 with your simplex "story".
>>
>>16243061
>I'm surprised you are learning abstract math yet are so opposed to me taking your problem and abstracting it then recasting it in a different form to get the answer easily.
you fail to do that and you fail to make any sense.
>Please tell me how you would find an operator del with the property del^k = 0 with your simplex "story".
oh ok you were just a literal ranting schizo this whole time.
>>
>>16243110
>oh ok you were just a literal ranting schizo this whole time.
The answer is to just replace -1 with e^(2*pi*i*m/k) in the alternating sum in the pic >>16241233
I gave you the answer. Now good luck proving it satisfies del^k = 0
>>
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I'm looking into the fact that a fractional brownian motion is not a semimartingale, but I'm having a hard time understanding a certain point in the proof : it is said that if a process has a quadratic variation of 0, then for it to be a semimartingale, it must have a finite 1-variation, but I found no proof of this, I have a hunch that it's due to the decomposition as a local martingale and a process of bounded variation, but I really dont know what to do with all that, could you fellows give me a hand ?
>>
>>16242256
>just the cliff notes.
Look at math books for physicists or engineers. They're pretty good for just distilling the things you'll need.
>>
>>16243378
If you have a continuous semimartingale [math]X=X_0+M+A[/math], for a local martingale [math]M[/math] and a BV process [math]A[/math], its (predictable) quadratic variation [math]\langle X\rangle=\langle M\rangle[/math].
Wlog you can take each [math]M^{\tau_n}[/math] bounded, for a localizing sequence [math](\tau_n)[/math], and also [math]\langle M^{\tau_n}\rangle=\langle M\rangle^{\tau_n}=0[/math], implying that [math](M^{\tau_n})^2[/math] is a martingale with [math]\mathbb E ((M^{\tau_n})^2)=0[/math], implying [math]M^{\tau_n}=0[/math] a.s.
This extends to [math]M=0[/math] a.s. because for any [math]t \geq 0[/math], [math]\mathbb P(M_t\neq0)\leq\sum_n \mathbb P(M^{\tau_n}_t\neq0)=0[/math] and modifications of continuous processes are indistinguishable.
So if [math]\langle X\rangle=0[/math] then [math]X=X_0+A[/math] which is BV.
>>
>>16243900
Got it, thanks man
>>
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>>16240472
>>
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>>16241294
You should read this book.
>>
>>16241363
Axler's book is free on his website.
>>
>>16241363
Why would anyone waste their time studying a theory? Study some measure facts
>>
>>16242244
Sounds like my dad's college experience
>>
what's the most esoteric out of touch branch of mathematics which will never have any practical application?
>>
>>16245814
large cardinals
>>
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If you throw a ball from height h meters and with velocity v m/s, what does the angle alpha need to be in terms of h and v to maximize the distance in which the ball lands when it falls to the ground?

Hint: it is not 45 degrees because 45 degrees only applies for h=0.
>>
>>16245907
>homework
>>
>>16247100
Not homework. I came up with the problem for recreational math
>>
>>16245907
Range can be expressed as a function of angle. Differentiate and find the roots
>>
Are you guys worried that AI is going to steal your mathematical jobs?
>>
>>16248524
Not literally today. But they do seem to be improving fairly fast, in 5 years yeah probably.
>>
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>>16248524
The first computers were invented to do mathematics. It's right there in the term.
They've been threatening to steal our roles since their very conception, and yet, all they've done is make it easier to do extensive, tedious calculations.

So, if anything, I'm pretty optimistic.
>>
>>16245907
Look here >>16249417
>>
>Got the highest ever grade in a PDE course.
>2 semesters passes
>??????
>Barely remember anything.
Is it over?
>>
>>16249907
No
Normal part of the human experience
>>
>>16249907
You still probably have some of the basic intuition, and can relearn it all in a few weeks if you actually need it
>>
how do I pass calc 2 this summer. these concepts and rules regarding playing with integrals aren't getting sponged by my brain as well as calc 1 concepts
>>
>>16250246
You mostly just grind them until you can do them fairly quickly. I basically just dedicated half an hour a day for a few months before my odes class to practicing the various techniques
>>
>>16240545
transfinite induction and recursion, yes
>>
Who came up with the term "positional" when discussing positional games?
>https://en.wikipedia.org/wiki/Positional_game
I tried to search for the earliest paper to use that word and I found Hales & Jewett (1963) to be the earliest, but I just want to double-check here on the off chance someone here knows an earlier usage of the word 'positional'.
>>
>>16250458
As far as I searched the term was first used in a 1967 book by
the same name, published by Nauka. Author unknown.
>>
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>>16251550
>>16250458
Hold up, spoke too soon. By the attached PDF, reference 11,
the authors Nikolai Vorob'ev and I.N. Vrublevskaya.

But then again, I might have found the second time the term
was used.
>>
Posting some kino

https://youtu.be/vUJEG3tUVaY
>>
>>16248524
>Gram Rothschild theorem
The jews are behind Instagram and Israel!
>>
>watch pic rel
>name drops protocols of learned elders of zion in the first scene
>says nothing else about it
>haha whoopsie!
Is being Jewish like playing Cops and Robbers by yourself as both sides?
>>
>>16251773
That's some good kino
>>
What's the best starting point in math if I haven't done any math since highschool 5 years ago?
>>
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I'm doing my masters in the fall, but I don't care about math anymore. I'm just scared of being in the real world and having a real job again.
Actually, I haven't done any math in over a year because I ran out of classes but had to take electives to get my degree. And I've been much happier with zero math.
>>
>>16254071
>I don't care about math
>I haven't done any math in over a year
>I've been much happier with zero math
So why are you posting in this thread
>>
>>16251791
>>name drops protocols of learned elders of zion in the first scene
does this actually happen?
>>
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>>16253564
>>
>>16248524
I have already lost hope of getting a proper job in mathematics. However, i still do to entertain myself.
>>
Hello I need some resources for math that cover the basics but I have some requirements
1) they need to explain things well unlike some other resources. I struggled to understand quantifiers because when I saw "for all x, there exists a y such that" and I would get confused as to what it meant, until I realized that confusion was that I didn't understand if "for all x" meant that y would be the same for all of them or that there exists a y for each individually. Some resources clarify this like some university of hawaii page.
2) I want more practical uses for things like statistics, something where you're given data and you have to analyze it with python would be best.
3) a decent book on proofs and math foundations, again something that isn't retarded and actually explains things, not some backwards rigorous autism, so actually showing why you'd do it one way and not another, etc.
Thanks
>>
>>16248524
Is that output any good?
>>
>>16242605
>3blue1brown
This any good? The visualizations are cool but they just seem like a way to make you think you actually understand what is going on, without actually being helpful in actuality.
>>
>>16256769
``For all'' really should be called ``for any''.
>>
>>16256855
Or "for each", I agree it's confusing and it makes it even more frustrating that this doesn't seem to be clarified when it is presented. Many such cases, that's why I ask for something where I don't waste my time trying to decipher the notation instead of actually learning new ideas.
>>
>>16248524
We are progressively moving towards constructive mathematics and the use of proof-assistants for proof writing.

https://leandojo.org/
>>
>>16256778
damn you're fucking retarded. it's hilarious you're really trying to front right now but all you managed to do was expose to everyone how big of a fucking retard you are.
lmao if you're gonna actually learn math you have to work through textbooks, or watch actual lectures while taking serious notes. how retarded are you? obviously 15 mins cool visualization youtube vids wont actually teach you math. holy fuck you're retarded. fucking obviously it is at best a supplement.
>>
>>16256769
all your "requirements" betray a serious lack of any kind of understanding of math, combined with an arrogant attitude that will prevent this from being rectified.
>>
>>16256774
That's an exercise for the reader.
>>
Does there exist a scalene triangle such that the resulting disphenoid is space-filling?
>>
bump
>>
Suppose H is a subset of a group G. Does it follow then that H is a subgroup of G?
>>
>>16257252
Nope. The empty set is never a subgroup. Also {1,-1} forms a group under multiplication and {-1} is a nonempty subset of it that is not a subgroup.
>>
>>16256913
nta but who are you arguing with
he didn't say any of that shit you're arguing against, he just asked if 3b1b videos are any good (even said he himself has doubts about them) and the answer to that is yes, they are a good supplement (to rigorous learning from elsewhere) for helping intuition/visualization about a topic
>>
>>16256778
Yes they are good. I'm sure all of us have had lecturers that couldn't teach a topic for shit, these can help. Sure his stuff might be a simplification at times but that's what textbooks are for. Combine the two and you have a winning combination.
>>
>>16257252
What does that even mean? lol.

t.mathlet.
>>
>>16257252
If you're going to make /sci/ do your homework at least make it nontrivial
>>
>>16257258
>>16257650
>>16257664
newfigs
>>
Niggas will do literally ANYTHING but read the assigned textbook. They'll watch that one Brooklyn Jew with the lisp for 40 minutes and come out of it with a surface level understanding rather than spend < 1 hour reading the assigned section, doing the examples, and doing the problem set.
>>
My boss went ballistic today because I compared two quotations from different companies using percentage difference rather than percentage increase/change.
How can I best explain to him that he's an idiot?
>>
>>16258123
send him a copy of Lang's Basic Mathematics
>>
>>16257370
>Combine the two and you have a winning combination.
Oh yeah of course, but you do have to combine them, whereas his videos are just some nice graphics.
>>
>>16240472
So a partial derivative is a limit?
>>
>>16258264
bet you're hoping we'll call you BASED right?
BASED smartbro who KNOWS you can't really learn math properly from 3b1b vids... you're really smart and redpilled and BASED, not like all the normies who think you can learn math properly from 3b1b vids...
BASED. take this. feel good about it. you are smart. and you are special.
>>
>>16258123
I don't understand. Isn't percentage increase exactly the percentage difference? Do you have an example?
>>
>>16258276
Yes
>>
bump
>>
>>16257028
bump
>>
What are the prerequisites for Riemann geometry?
>>
>>16259560
Multivariate calculus and basic topology.



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