#help-39
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It depends on the context
You did lol
that's just explaining the difference
They clicked ❌ but didn't answer any questions abt the context 😔
It is more accurate for describing the central tendency of a data set because it is not affected by outliers
what's central tendency
Tendencies in the center 😎
It describes the middle point of a data set better because it's not influenced by bigger/smaller numbers at the ends
Which is basically what I said before
yes this is all the same answer
why is the thing you;re trying to measure affected negatively by outliers? is it tautological?
i hope not
This is why context is important
what
🤦♂️
What??
@glacial tangle What do you mean by "better"
Which is more useful
Well in what context are you looking
if the question was like "why is milk better than water", you wouldn't be like this
?
Am I going crazy
Average is good when there's not a bunch of bigger numbers dragging it up
why did he open another help channel 😭
ideally you'd get them all,
arithmetic mean, median, quartiles etc
SD
to analyse your data
just one aspect by itself isn't that helpdul
agreed
thanks
whether the mean or median better represents your data depends on your data
no point if op isn't here
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26 − 7(3 + 5) ÷ 4 + 2
you can so long as you maintain the bracket
Do you only distribute with equations?
i wouldnt say theres a single benefit to doing so here though
Ohh yeah you right. I forgot to keep the brackets
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Hello 👋 I'm working through some integration problems and I ran across this problem. The answer key says what u-sub we're expected to use, but does not show the steps.
The u-substitution being x * ln(x), du = (1 + ln(x))dx, dx = du/(1 + ln(x))
Not really sure what I can eliminate with that.
to be honest that doesn't seem like the most straightforward substitution you could do
I'm at a loss at what else I could do.
lnx perhaps?
i would try that first
ln x is u
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need help understanding what the natural pairing is. The dual space is just the set of homomorphisms from V to the complex numbers right?
wikipedia just says this, im not sure hwo the pairing defines a function
is this from fulton
oh yes it is
i think i recognize the font
yeah
i remember getting frustrated at this section actually
i think the natural pairing is gonna be <v*,w>= v*(w) because v* is a map V \to C
or whatever order you want the map <,> to take arguments in lol
here fulton decides that v* comes first
seems pretty natural to me
oh wait
I have seen this before somewhere in linear algebra it was called something else, yes it makes sense now
thank you for the help
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200 * cost = x
dx/dt = 12
i used sint = 100/200 to find t = 1/2
differentiated the first equation
-200 * sintheta * dtheta/dt = dx/dt
i solved for dtheta/dt and got -12/100
but the right answer is -3/100
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e
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e
is this incorrect because the length of string also changes as x changes
but using tantheta = 100 / x, the height remains constant irrespective of x?
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Can someone help me with this?
neon
Then write the same thing in polar form and you'll find the requisite values
@glacial sequoia I did sth like this
Am I on the right path?
But then I have no idea what to do next for the deduce part
Can anyone help me
Ok thanks
yeah
let sqrt(A) = a + bi
then square both sides and equate the real and imaginary parts to find a and b
By the way tho
I wanna know the reason why we are doing this
Or is it just a rule that we follow?
well
the square root of a complex number is also a complex number
we don't know what it is but what we do know is that it can be written as a + bi
so we do, and then find a and b using algebra
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that would just be a different system entirely
what do you get if you multiply out the matrix and vector on the right side?
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can someone help me
Well do you know the multivariable chain rule
yead i know
but if u look the question carefully u'll its harder than normal
ur wrong at the last
neon
i know what u mean
hmm my edit didn't go through
I'd just differentiate both sides wrt t again and sub in theta for t
and just sub in r here
and see what happens
not thing happened
the partials of x and y wrt r and theta
brother can u write on paper and send me
nah don't have any on me
I think maybe you need to do something like this
and then after differntiating everything and subsituting the formula will probably pop out
make sure to not forget the product rule
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Can you help solve the differential equation
I attempted to solve it using substitutions, such as z=sin(y) and z=cos(y), but they did not lead to a straightforward solution. Is there a better approach to tackle this equation
First expand and divide across by x
it should be a linear ordinary differential equation
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The blue
Ignore my leopard print water bottle
I can't get rid of the density
It's because I'm not too sure if I did the differentiatls correctly
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how do i do this
this is what i tried
maybe i could use the substitution with tg x/2
but that didnt seem to help at all
kings maybe
huh?
kings rule
i havent heard of that
wait no that doesnt do anything
now im curious, whats the kings rule?
you should write sin^4 + cos^4 as 1 - 2sin^2cos^2 and divide the top and bottom by cos^4
but yeah first use kings rule to simplify the bounds
you mean by cos^2?
i would see what happens if you transform cos^4x into something with sine or the other way around
oh no i see what you mean
yea, but thats solving it using a trick from trigonometric equations
well its not rly forbidden to do that
i feel like there has to be a more clever way
neon
neon
why can you apply it twice
cuz it would be f(pi-x)
which would kinda fuck this up, no?
f(pi - x) is still f(x)
THATS RIGHT BECAUSE ITS TO THE 4TH POWER AND THE NEGATIVE COS IS CANCELED
this is genius
although i dont see how it helps me much
but its really interesting
you need to do it before doing all this
otherwise you have a bunch of points at which tan x is undefined
since we're going to be substituting that next
i dont know what that proves except that the function is symmetrical about x=pi/4
also working with (0, pi/2) bounds is always good with trig functions
wait so
is what i did here alr?
like, i should be continuing it from there, right?
can you notice that $f(x)=\frac{1}{\sin^{4}x+\cos^{4}x}=\frac{\sec^{4}x}{1+\tan^{4}x}=\frac{(1+\tan^{2}x)\sec^{2}x}{1+\tan^{4}x}$ which is in VERY good form for a substitution $u=\tan x$
如月あやみ Kisaragi Ayami
.
you need to divide by cos^6 like that
and maybe you should apply this one more time and make it 8 times the integral from 0 to pi/4
alr this is pretty cool
but tan x is defined for all of [0,pi/2]
oh, the bound is 2pi
yeah i see what you mean
and probably one more time because the limits will be from 0'to 1
yeah visualising the graph cutting it into 8 pieces would be the first thing i do lol
wait, i did something
not even considering the fact that it eliminates discontinuities
I told you you need to divide by cos^6 if you want to do it like that
we need a sec^2 up top
and write it as 8 times the integral from 0 to pi/4
fiiiiiiine, let me redo it
ok, i did it
up until the division by cos^6
cuz it just doesnt make sense to me why you wouldnt divide it by cos^4
because in order to prepare for a tan x substitution you need to create a sec^2 x to be in the numerator
@dusty heart Has your question been resolved?
just simplify
this exercise will be the death of me
i dont get it no matter how many time the neon guy tells me there need to be a sec^2 up top
the denom can be written as 1 - 2sin^2xcos^2x
is there a way to check for concavity if the second derivative is too complex to do ??
can you write that on paper?
matter of fact
solve the whole exercise on paper and show me if its that easy, maybe then i wont get lost in explinations
ight then hint me what this means
that kinda resembles a for loop in c++
that's the integral after few simplificaitons
using simple trig identities
you then multiply by sec(2x))^2
to make a tan sub
wasnt the whole problem with that that the integral is from 0 to 2pi?
what
whats the periodicity property
educate me
pls
ill show you where i got in one of my attempts
the function repearts itself after pi/2
so 2 pi is just going to be 4 times that integral
yea right, did it
what integral
if you mean this, then write it in such a way that i can understand it
cuz idk how you got the nominator to be 1 + cos ^22 x
right
dude, i got 4 different paths in my head for this exercise, thats why im getting things mixed up at this point
keep going
write your solution
idk what path you wanna take to solve this exercise
mutiply with sec^22x
ye
and then?
make the denom in terms on tan2x
you mean tanx right?
tan2x
its more crazy than i thought
wanna see the solution?
its in romanian, but i think you will understand it anyway
sure
yeah it is there
the method I suggested was easy to begin with but complex at the end because of tan2x discontinuity
dude to discontinuity there's change of domains and shit while substituting
but the book method is fine
is there no way to do it without sec x or integral from 0 to infinity?
i feel like its way to extra
there's no problem with infinity coming in your integrals
thats some premium knowledge that i do not possess
whatever you say buddy
oh
damn
that makes sense
damn i just understood it
bro, ngl, whatever sec you were trying to pull
like, i didnt understand it, and it seemed hard af
I'll tell you why
when we're dealing with cosine squared or something like that in the denominator
we multiply num and denom with sec^2x
why
this is because we can write the denom in terms on tan^2x
how
never been told that before
so now you've got the denom in terms of tan
and the numerator had sec^2x
so dy/dx of tanx is just sec^2x
makes life simpler
that's called a tan sub
i do tan x/2 substition all the time
like with the sin and cos formulas
i just never worked with sec x
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Well, first of all you have to check whether that denominator can be 0
Then, you can multiply both sides by that denominator and do the calculations
By writing z as x + iy (as they're suggesting you there...)
z^* is conjugate right?
This...
i did
sort all terms. those with i on one side, those without on the other.
i did that already
show.
if you have done this, you should have a real number on one side and an imaginary number on the other side, right?
that was suggested.
after writing as x+iy and after multiplying by the denominator you should have:
2x+2iy = i(3-x+iy)
now simplify and sort all terms. those with i on one side, those without on the other.
you said this, i just want to help you to check it.
but anyway, go on with this.
sry for the confusion, i thought i did something wrong
so the side with real numbers is x and the side with imaginary numbers are y?
if you have this, you did something wrong.
😭
iz should by something like 2x+y on one side and i(3-x-2y) on the other.
i have that
so your real number is?
but how can i find value of x and y
we come to this soon. please answer: your real number is?
2x+y
and your imaginary number is?
3-x-2y
exacty it is i(3-x-2y), not 3-x-2y
ok
now the most important question: how can a real number equals an imaginary number?
there is one case, where it can.
when its 0?
exactly.
so i get a simultaneous equation of x and y
yes
2x+y =0 and 3-x-2y=0
um what does z* mean? y+xi?
x-iy
Conjugate complex
ye
guess I was late XD
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Hi,
PI_1 : 5x-2y-z=-2
I wanted to understand why i cannot find the normal to pi_2 by doing the cross product of
(1 4 -3) x (5 -2 -1)
i thought that the line of intersection is paralllel to the normal of the two normals of the planes
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i wanna solve both of these equations separately. i tried doing the first one and i replaced the root of x^2-x-42 with t and got -11t = t^2 but idk what to do from there
i think the second one must be solved in a similar way
!xy
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t^2+11t=0
t(t+11)=0
t=0 or t=-11
matter of factorizing
but it cant be -11 since its a square root right
so after that i should use the quadratic formula and find the x1 and x2
yup
yup
x1 = -6 , x2 = 7
so those are the 2 solutions to the first problem?
what about the second one, how can i factorize it?
but under the root its +20 and on the other side its +10
hmm
i got 3t = t^2-10 by adding 10 to both sides
so i make a quadratic equation out of that?
so you got t^2-3t-10=0
yeah
first solve for t
then substitute back in
and solve again
these are the ts it gives me
oh no wait
i messed it up
its -2 and 5
my bad
so only 5 is valid
and then solve for t = 5
ye
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✅
im sorry for reopening but i got another question
after finding that t=5
and we replace t with sqrt of x^2 - 4x + 20
yes
the equation is sqrt of x^2 - 4x + 20 = 5 right
yes
so after that we should do both sides by ^2 and it equals 25
yes
x^2-4x+20=25
x^2-4x-5=0
yea
(x-5)(x+1)=0
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एक घन को एक गोलार्ध में इस प्रकार अंकित किया जाता है कि घन के ऊपरी चार शीर्ष गोलार्ध की समतल सतह को छूते हैं और अन्य चार शीर्ष गोलार्ध की घुमावदार सतह को छूते हैं। यदि गोलार्ध की त्रिज्या 1 है, तो अंकित घन का आयतन ज्ञात कीजिये।
What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
A cube is inscribed in a hemisphere such that the upper four vertices of the cube touch the flat surface of the hemisphere, and the other four vertices touch the curved surface of the hemisphere. If the radius of the hemisphere is 1, find the volume of the inscribed cube. This is the correct translation right?
हां मुझे ऐसा लगता है।
So, cube is inscribed in hemisphere and we have to find its volume
बिलकुल सही
मुझे नहीं पता कि वृत्त की त्रिज्या को घन की भुजा की लंबाई से कैसे जोड़ा जाए।
agar bhuja ki lambai x ho to vikran ki lambai kya hogi?
?
यदि घन की भुजा की लंबाई x है, तो त्रिज्या होगी (जैसा कि मैंने गणना की) x * वर्गमूल(3/2)
Basically the volume of the cube will be (2/3)(root(2/3))
No wait
Is this correct?
yeah
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How do you type in Hindi???
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Can anyone guide me through the solution of this question?
Consider a 25x25 rectangular grid where each side is parallel to the x-axis and y-axis. In each row and each column, there is exactly one cell colored red. Find the largest positive integer 𝑛 such that there exists a polynomial 𝑃 with real coefficients whose graph 𝑦 = 𝑃(𝑥) passes through 𝑛 points on the grid but does not pass through any red cells. (We define that the graph passes through a cell if there exists a point on the graph that lies on the edges or the corner of the cell.)
the position of the grid is not given btw
@north talon Has your question been resolved?
<@&286206848099549185>
Where is your attempt
i answered 600
Show your working so that we can help ur
im not sure where to start
but the answer is probably 600 cause sin(x) expansion right?
taylor expansion of sinx has real coefficients
So what
Just go and evaluate your life if you do not need help and stop waiting our time
what?? are youe evn helping
we can make a polynomial that looks kinda like this
hold on
why is that so gpt looking (sorry if it isnt)
They did not specify where the red are located
they said in each row and column the exist only 1 red read the question carefully
oh dang
so the reds form a diagonal
not neccesarily
mb
No
No
do you understand now
in every column P(x) can either go over or under the red square
this is also possible btw
i dont get what youre saying
yes
i was thinking if the reds were in this shape
then P(x) could pass through most of the squares
maybe im over complicating
i will show you something
give me a second
Note: The must only be 1 red in any column and any row
Note: The must only be 1 red in any column and any row
yeah?
that satisfies
You still get 600
you can use any method you want
i am. Going bye for real
.close
This
okay then if n is 600 there then it would have to hit every non red tile which isnt possible in that img
if it crosses corners by definition it hits the red tile
It must form a diagonal
it doesnt have to
Why
this works
The way you drawn it where will a line pasd
pass
the polynomial can't pass both above and below a red square
yeah thats what im saying bro😭
did you get an answer?
if i draw on mine itll be super messy
my ans is from this
I got 600
how?
let me run it on python
black lines are the ones that P(x) doesnt pass
interesting
$\sum_{n=1}^{25} \max(n-1,25-n)$
Axe
whys that equivalent?
or is it because we're choosing either above or below the red tile
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Sorry in advance if this question is a bit stupid
$$\gamma =\frac{L_{(A, A)}}{L_{(A, B)}} = \frac{L_{(B, B)}}{L_{(B, A)}}$$
Edmund Cloudsley
how do I find an expression for gamm in terms of L_(A, A) and L_(B, A)
nvm I see i thanks
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I have a paradox
Wouldn’t this break sequential limit test?
@rough forge @prime bramble
Mighty mathematician help me
The limit doesn't exist, so I don't think you can do algebra with it
How do you get there?
It’s just to lead contradiction
From the other limit manipulation
I mean how do you conclude the limit is 0
x = -x is the idea there
But I don't think you can just do DNE = DNE and proceed
I just thought a proof so I wrote it
And what are you trying to contradict? What are the assumptions?
The contradiction is that the limit exists
Just because you made a change of variables doesn't mean the limit is 0
But since sin^2x + cos^2x =1 it contradicts
But the function defined if we let x in N
Then it has a limit of 0
I didn’t change variable though
oh
It’s just manipulation I can do it with x but less neat t
You wrote it in the end x in N
but why are you saying then DNE in the beginning if x is natural?
oh I get what you did lool
Shorthand version claim for the sake of contradiction
Ya mathematician has a thing called conciseness right?
I am still confused by your contradiction lol
That proof is rigorous btw
I used it for a math competition when I was at high school
For $n \in \mathbb{N}$, the first manipulation line is saying $\operatorname{lim}_{n \to \infty} \sin(\pi n + \pi) = - \operatorname{lim}_{n \to \infty} \sin(\pi n),$ which is just 0 = 0, right? How exactly are we saying $\sin^2(x) + \cos^2(x) = 1$ is contradicted?
elliot
The point is, when x is natural number in this case the function actually has a limit whereas x is a real number it doesn’t have limit
I will refine it then
Here x is real, so is y. But how do you jump to the conclusion the limits are 0?
For f(x) = sin(\pi x) that is true
Just wait
But consider g(x) = cos(\pi x), this does not have limit 0, the arguments need to be the same to apply the trig identity. I think it is weird to do an identity like this as a limit, particularly when the limits in R do not exist
It’s for the sake of contradiction though
And one assumption without relying on any existing theorem lemma or corollaries
Here
ok i was really dumb
but hmm
The thing I am concerned with is you are assuming both limits are equal
Isn’t that very weird
It was for contradiction though because saying sinx s limit doesn’t exist is quite hard
That's very possible, especially when you have periodic oscillations like this
x=-X what’s x?
It’s not contradicting to sequential test right?
So sequential test is like whenever the yielded value differs it proves that the limit doesn’t exist
A function f:R \to R is not a sequence, a function g:N \to R is
True still I just feel a bit weird
But it can the case that a function has no limit but using a sequence can lead it to a limit?
Yes, maybe its like including all of R can add too much info that breaks the nice countable and discrete behaviour you get with N
There's a whole study of pointwise convergence of functions, which is when you have a sequence f_n: R \to R and look at the values for some x \in R
That’s how it is… I was always confused with this example though
Now thinking about it I accept it
I genuinely get a excellent mark for competition at high school with that proof which isn’t my original I think but I don’t recall where I got it
What does the question ask to prove?
That limit DNE?
Ah okay I think I see what you're trying to do now
There’s no question it’s just I am exploring reasons why x in N limit exist and x in R it doesn’t
And to make it concrete I prove that X in r it doesn’t have limit
Yeah okay and then I accept your argument, I just didn't realise at the beginning we assumed it had a limit
I like mathematician like Sheldon so I learned to be super concise but I think I have done it in an awful way 😭
You have exploited periodicity to force the limit to be 0, but you could have very well forced it to be any value in [-1, 1] by the same logic
Yes
Indeed but it doesn’t stop me forming valid contractions
Lim (sin^2x + cos^2x)=0 which is clearly contradiction
Well what does it mean to have limit 0 rigorously, could you contradict this from knowledge about sin(x)?
This is assumed for the same of contradiction
Whenever x-c is within delta neighborhood then it follows sinx - sinc is within epsilon neighborhood
No I said x in N it had limit 0
Not when x in R I think you misunderstood
I thought the goal was to show $\operatorname{lim}_{x \to \infty} \sin(x)$ does not exist
elliot
I assumed the limit for x in R exist then I started the manipulation, with which I showed that sin^2x + cos^2x =0 contradiction
No I was just asking why when x in N it has 0 as limit but when x in R it doesn’t
That’s it
I never said sinx x to infinity sinx=0
You
You see here lim at the end of the proof
It doesn’t have lim x to infinity
It’s lim
So it’s for natural number
I just wanted to discuss why x in N f has limit and x in R it doesn’t
Well it's essentially because sequences are discrete objects which behave very differently to continuous functions on R. There's a sort of inclusion going on also from N to R
Now I kinda understand
Bcs I am not studying mathematics as my major so these logics are hard
Btw that proof for nonexistence of limit is super elegant, it relies no existing theorem, lemma or corollaries. It made only one assumption and led to the contradiction
What is that assumption?
The limit x to infinity sinx exist and let it be L
Didn’t write it there I have bad habit of omitting great deal of detail for copying mathematicians wrong
Yeah I agree it's nice. My instinct after saying L=0 necessarily would be to essentially argue that sin(x) = 1 for arbitrarily large x, which would contradict that convergence
I got it when I was at middle school
From one senior I think
And most importantly this proof is super short, in a way that it relies nothing than basic calculation
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Help
I need someone to verify if I find the correct pointwise limit for the sequence of function
Here’s my solution
The question grade level? It’s an elementary analysis proof
Ah
Help me
As a Econ student I am sure I had made a lot of formatting mistakes so please help me to point out them and also help me with the refinement
I wouldn’t say its elementary though but it’s optional for economic, engineering, and humanities majors so it’s not very hard either
Hav you shown the critical point is indeed a max?
So its like uni level
Hell I made that mistake again😭😭😭
This time look at pink part
Here you go
It shows for all x in the interval it converges to 0
And even this fixes the issues I must really remember not to make that mistake again
a=x^2
Yes but for most people it’s freshmen course
btw if |g| < 1 ln(g) is not defined for g <= 0
q is defined on (0,1)
I think you mean q right?
Yes that’s a point
I should have fixed it I am fixing it actually
Done
I mean I am bad at math so those stupid mistakes almost seem inevitable for me which made me sad
yap yap yap
Oh
I dont think im ready for it lol
I really am… especially when I was at middle school
Why did you substitute a = x²?
Only to make algebra neat
And since it’s in the interval it doesn’t matter
X in (0,1) so lnx is always negative
I don't think it's true that the limit is 0 for [0,1]
Only for a sequence x_n = that long expression
I think it’s called moving sequence or something?
so it’s always 0 for any fixed but it diverges when x takes the diagonal sequence
x_n should be called a diagonal sequence if my memory serves
There’s some introduction of this on rudins
And since my school incorporates rudins principle of mathematical analysis as text book for RA it’ll be my textbook too soon
ok
How about other parts
e^(-1/2) i think instead of e^(1/2)
Or it should be called limit superior
Yes you’re correct
I will fix it now
Also what is that next part? Do you wanna show that it's not uniformly convergent?
Find the interval where it converge uniformly
I haven’t had any clue
Yet
Fixed
Well you shown that it doesn't converge uniformly on [0,1]
I need to determine sub interval of [0,1] if there can be any that uniform convergence holds
It’s on rudins book
For x > 1 you could show that it doesn't converge point.wise
You would basically have a product of numbers greater than 1 which would go infinity
It asks me the pointwise limit if I were to find all then I solved the third question already
And maybe that diagonal sequence is to be found at last but I found it before
On rudin s book, I don’t think this is hardest
I have one involving factorial
Which is making me so clueless
And also arctan(nx)
(uniform convergent => pointwise convergent) <=> (not pointwise convergent => not uniform convergent)
I have Screenshot it
cool
I need to master all exercise on rudins so that I won’t drop out from RA
That was my very first assignment exercise last semester
on D = R
Will final for freshmen level analysis course include these question
D=R?
If you drop out I will lose my mind
domain all real numbers
Is that a part of real analysis
funny thing is i never did this part as rigorous as you
haha i meant arctan(nx) was defined for x on (-oo,oo) in my assignment
I want to show that it converges uniformly for all restricted domain (or equivalent a compact set)
And this one has been troubling me for a while
It’s on rudins so it has to be true just how it can be proven
first always make sure that some conditions are met before you prove something that appears to be true
arctan(nx) is uniform convergent??
Yes on restricted domain
[-M, M]
and M?
Arbitrary
hmm
What I have in my notes is that the limit function wouldn't be continuous
If you consider the limits on [-M,0), x = 0 and (0, M]
You know arctan(x) right?
Yes
I am graphing the family
Yes if it’s 0 then it’s weird
Or actually it’s only 0
so you see it will have a jump in the origin
Investigate and show uniform convergence of arctan(nx) with respective domain
limit as n->oo will be pi/2 and as n -> -oo will be -pi/2
You said on [-M, M]?
Investigate it for whether it converges uniformly on [-M, M]
well unless M = 0 it can't
Can it be
[-M, 0-delta] unions [delta, M]
That it converges uniformly on both sets respectively
Then it should be the answer
Still it’s arctanx
I don’t even know Bernoulli number how the fuck can I even expand it
I am definitely going to fail
And this another insane thing sum x^k/k! and prove its uniform convergence interval
I love how a non-math student does stuff more rigorous than I have done before 🥰

Not I am not rigorous
😂
I made too many mistakes
🫵🏻 ?
Especially those questions with larger index number
And those inequality proof is insane
You talking about proving or arguing the limit?
Show that |a-b|^alpha\geq than |a^alpha -b^alpha|
For that convergence I must do expansion right?
Show that $|a-b|^{\alpha} \geq |a^{\alpha} -b^{\alpha}|.$
𝔸dωn𝓲²s
This inequality after the introduction of holder inequality is insanely complicated
Alpha is in (0,1)
Also on that book
Even after expansion I still don’t have clue
Like I don’t know what to argue
Alpha is in (0,1)
I don’t know you expand it and I don’t even have a clue for that direction
Is that inequality from a book?
I was doing through construction function
And use concave property to show it
Yes
For rudin s
After the chapter where holder’s inequality is introduced
My thought is that concave function might hint the result though but manipulation is somehow too complicated
Oh maybe it’s not
I actually think of a new way using the same argument
Iam on it now
,, \abs{x^n-b^n} \leq \abs{x-y}^n
𝔸dωn𝓲²s
Do you think the concave property is the way?
I never even have heard of this before
Guess I haven taken real analysis properly yet
yae
If I solve this question then I solved 2/3 of all questions related to inequality on the book
From rudins
I am working on it marry Christmas again
If you apply the concave property are you defining a function?
Not necessarily but a parameter to formalize the proof I think
In an abstract way yes
A general function I guess
Last time it was a failure because I was too specific I guess
Yes
That’s my current thought
f need to be something that satisfies that concave property
I was originally doing a specific function construction which turned out to be dumb
I think x^n is the simplest for that matter
This must be a reason it follows the part of concave and convex function and holders so I will think this direction
f''(x) = n(n-1)x^(n-2)
You spoil me
I can’t even master the stupid textbook for 3 months almost like I was crying almost
don't worry i wouldnt bee able to prove half this stuff
