#help-36
1 messages Ā· Page 203 of 1
C'mon guys show some mercy on high school guy
Who has to do 18 more such questions
why would abc > -1 need to be proved then
oh at least
okk
i think a proper fraction is a rational number between 0 and 1
Yes as Ann said
ah
#unsolvedproblem
<@&286206848099549185>
..
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Which one is greater 50^99 or 99!?
Please don't occupy multiple help channels.
consder: $50 \prod_{j=1}^{49} \bigl(j(100-j)\bigr)$
Which is greater 50^2 or 49*51?
Rbit
What you did?
pair factor 99! symmetrically
Clearly, you can observe: $$100j-j^2\le 100*50-50^2=50^2$$
2500, 2499
Please make it simple
Rbit
What do you not understand
Repeat for 50^2 and 48*52, and so on
Could you guys please make it from basics
?
I meant 2496?
?
I don't
Then?
You're only interested in which one is greater
50^99 = 50(50^2)(50^2)...
99! = 50(49*51)(48*52)...
Yeah
... well, which is greater between 50^2 and (50-n)(50+n) ?
I.E: $$j(100 - j) = 100j - j^{2} = 50^{2} - (j - 50)^{2}$$, what follows from this
Rbit
50^2 >(50-n)(50+n)
Right, so it should be clear which of these is greater
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can someone walk me through this question?
well, you can rule out m=2 and m=4 immediately bc there aren't enough positive integers below these.
yep
i suppose that a more hands-on rephrase of this question is:
you have a set of five rods, each of which has length an integer number of centimeters. the largest of these is m centimeters long. but no matter which four rods you pick, you can't make a quadrilateral out of them that has nonzero area.
... what would even one such set of rods look like, i wonder?
i would imagine that chaining 4 of them together into a quad would mean they either don't join up or they JUST BARELY do, and when they do, there isn't any way you can flex the structure
and it has to be a single line if it even does join up
i see
oh yeah this will cook actually.
so one of the "rods" would have to have a length greater than the rest combined
or, equal to
as you said, that would form a single line in that case?
in this scenario, I can assume that m must be greater than 7, since if we take the second largest integer in S and call it x, the least x can be is 6 because it must be greater or equal to the sum of the smallest integers, 1, 2, and 3
am i correct to think this?
well let's take this a bit further
let's say our 4 smaller rods are 1, 2, 3 and 6
if you try to make a quad out of them, it just barely closes up with the 1, 2 and 3 adding up to the entire length of the 6
what could the fifth rod be to produce the same behavior
(or fail to close up at all)
the sum of all the previous terms, or larger?
yeah but we don't want "or larger" cause we need m to be as small as possible
also not all the prev terms
i realised, since only 4 elements are used
so therefore would it be the sum of all elements, not including the first element?
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what digits can you get from 8, 0 and 5 by removing up to three lights
well actually no
from just 8
cause it's only the first digit display that's faulty
yeah uhh the thing is i don't really understand the premise of the question
so each player has a score of 5 digits?
and what do you mean by removing up to three lights?
so would 8, blank, 0, blank, 5 count?
no
i mean literally look at the displays that they've printed out for you
yeah
each of those white circles is a light that's on
i can ask something about set?
literally not even math just pattern recognition
!occupied
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ah
start with the pattern of lights for digit 8
what digits can you turn it into by turning off up to 3 of those lights
0, 2, 5, 6
ok
9
and which of these could be the first digit of a darts score (which has to be between 002 and 501)?
(considering also that the last two digits are 05 and displayed normally)
2
2 only?
any others?
and you are correct
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Hello i need hekp with g
so far ive split ln2n into ln2+lnn and then i crossed ln2 out
and now i am stuck
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Hi! I forgot how to do the top half
If someone could explain so I can continue the rest of the derivative myself
I would try to express the difference on the top half as one fraction
(Use a common denominator.)
The common denominator is where Iām stuck
Multiply both halves of both fractions such that the denominators are equal
If I multiply 5/z by h it would give me 5h/zh not z+h
I donāt understand how I would get to a common denominator by multiplying
I would multiply by the denominator of the other fraction
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I dont understand the implication from the triangle inequality
To start with $|s_n-s| = |s_n + (-s)| \le |s_n|+|s|$
BOSS
How does this imply it is less than 1?
what are you starting with
great. that context was important
BOSS
yea that works
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if the matrix is half empty does that mean it's all zeros or it can be any value
just assume 0. the probably would be too hard otherwise
These are 0s
@jagged nacelle Has your question been resolved?
thank you
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What did I do wrong (the drawings are the method I used)
Is this correct?
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@trail shale Has your question been resolved?
<@&286206848099549185> Hi if yall wouldnāt mind checking my question that would be great
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yeah you need to apply integration by parts first
x^2 doesn't fit in with sec^2 or tan x (when you differentiate sec^2 x, you don't get anything with x^2)
ok then
Integration by parts by using the DI method! This is the easiest set up to do integration by parts for your calculus 2 integrals. We will also do 3 integrals to illustrate the 3 stops of the DI method.
Dear calculus teachers, please let students use the DI Method (& why it is really the same as integration by parts) š https://youtu.be/8xPfNu...
given u = 2x^2 and dv = sec^2 x tan x
tell me what you get for du and v
du = sec^2 x dx
okay you're doing the integral for dv I see
the problem is that you mixed your derivatives up
the derivative of tan x is sec^2 x
so that's not the right u-sub
What I am doing is I am taking sec^2 x tan x integral as 1/2 tan^2x and then applyingi ntegration by parts
okay fair enough, that's correct
then yes, you need to apply by parts twice
yeah thanks......I think I was making mistake in solving not logic š
so you should get $2x^2 \frac{\tan^2 x}{2} - \int \frac{\tan^2 x}{2} \cdot 4x \ dx$
south
which is why I recommended you this video
you still need to do the integration and so on
yeah
but the table method helps you check sign mistakes
it's easier to get the correct signs, if that's your issue
oh ok fine
alright no worries!
Thanks!
south with the clutch
@modest junco Has your question been resolved?
this isnt maths related but
why is this your username
bruh
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You draw a card from a deck of 40 cards, calculate the probability of obtaining a face card.
Its unclear
It is unclear
Hi @craggy plank
This
screenshot, photo of textbook where you got it from, anything available?
It's automatic translation
Itās alright, just send it anyway
Send the original question, whatever language it's in
Someone here might be able to give a better translation
\documentclass[12pt]{article}
\usepackage{amsmath, amssymb}
\begin{document}
Let $\mathcal{D}$ be a finite deck of $N = 40$ distinct cards, each characterized by a face $f_i$ belonging to a finite set of values
[
\mathcal{F} = { f_1, f_2, \dots, f_{10} },
]
each repeated exactly 4 times in the deck.
Consider a random experiment $X$ consisting of drawing a card $C_1 \in \mathcal{D}$. Let $Y$ be the random event corresponding to drawing a card $C_2 \in \mathcal{D} \setminus { C_1 }$ such that
[
\text{face}(C_2) = \text{face}(C_1).
]
Determine the conditional probability $P(Y \mid X)$ that the second card drawn shares the same face as the first, formalizing the solution in terms of combinatorial arguments and/or hypergeometric distributions.
\end{document}
Richard Mullin
Compile Error! Click the
reaction for more information.
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@twin pivot was original in English or no
No
what language then
Croatia
ok can you send the original Croatian version
right now i can say that the thing you call "face" is probably known in English as rank.
IzvlaÄi se karta iz Å”pila od 40 karata. IzraÄunaj vjerojatnost da Äe druga izvuÄena karta imati isti broj/lice kao prva.
ok, but our deck consists of 10 numbers rather than 13 as for a standard poker deck (but still each one is present 4 times)
is that correct
Poker ?
uh you know the most common type of playing cards
The standard 52-card deck of French-suited playing cards is the most common pack of playing cards used today. The main feature of most playing card decks that empower their use in diverse games and other activities is their double-sided design, where one side, usually bearing a colourful or complex pattern, is exactly identical on all playing ca...
anyway
whichever card you draw from your deck, 3 will remain that match its rank, out of 39 total.
But how do I know what cards the deck has
you don't actually need to know, do you?
you yourself said it's some ten ranks and each one is repeated 4 times.
...
Cards are drawn from a deck with 40 cards. Calculate the probability that the second card drawn will have the same number/face as the first
Translation
Å pil se sastoji od 10 razliÄitih brojeva i svaki se pojavljuje 4 puta (ukupno 40 karata). Jesam li u pravu?
Želim znati jesam li te dobro razumila u vezi "Ŕpila od 40 karata".
nemoj me zasipati brojkama, molim!
40 card
fuck, i try to ask you things in croatian (with google translate and my own knowledge) and you still do not understand?
Å pil se sastoji od 10 razliÄitih brojeva i svaki se pojavljuje 4 puta (ukupno 40 karata). Jesam li u pravu?
Hello, Richard
tell me what language you speak best. / reci mi koji jezik najbolje govoriÅ”.
Hello, Ann
What does 4 times mean?
-> šš· 4 puta...
Can i take a look at the original problem?
svaki broj pojavljuje se 4 puta
So 4/40
im trying to figure this out. the original is:
IzvlaÄi se karta iz Å”pila od 40 karata. IzraÄunaj vjerojatnost da Äe druga izvuÄena karta imati isti broj/lice kao prva.
which translates from Croatian as:
A card is drawn from a deck with 40 cards. Calculate the probability that the second card drawn will have the same number/face as the first
1/10
Ok, thanks.
but OP is unable to confirm any details at all
!status
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
sorry you're kind of getting in the way here
i try to ask you a clarifying question in english and you dont understand. i try to ask in croatian and you dont understand.
i ask you WHAT LANGUAGE TO SPEAK TO YOU and you dont answer
WTF?
koj jezik hoÄes da priÄaÅ”
I told you before
ali ti priÄaÅ” engleski
zaŔto me ne razumijeŔ kad te pitam na hrvatskom??
I understand
I'm writing a solution.
!nosols
As a helper, please do not give out answers that could be copied as a homework solution. Have the student work through the problem themselves and guide them along the way.
i'm slightly frustrated that i never received any CLEAR answer of "yes you're right", "no you're wrong" or "i don't know" to my question
ajde da priÄamo hrvatski, jel Äe to da bude lakÅ”e?
I'm walking them through the steps.
Yes
.
this is delightfully simple once you invoke a little Laplace and Kolmogorov
Ok
what the hell are you talking about
What Is laplacs?
<@&268886789983436800> this is definitely a troll.
what business do these big names have in such a basic probability problem
@frank ginkgo can you help
Yeah I'm inclined to agree with Ann. Even if such a solution exists, its not useful to the helpee. Also providing full solutions is against server guidelines.
Please help in good faith, and strive to help the helpee learn by helping them
Meanwhile still 0 help
Do you want help in English or Croatian
Try english
Did you answer the question Ann asked you?
just naming the principles
Cool, they're not helpful for something like this.
If English, you need to be able to answer the questions clearly
Ok
We can't help you if you don't answer our questions
Ok
Once again. The deck consists of 10 numbers which all appear 4 times, do you understand that
citing the principles helps contextualize why the formula works, not just what the answer is
Yes
itās literally how probability is defined in the first place
Itās a pre-uni probabilityā¦.
Look mate your options are either just accept that an elementary probability question doesn't need these principles and try to actually be helpful, or you can go brag about memorising 2 people's names in a different math server. Please don't reply to this message because I'd like this channel to get back on track
Okay, assuming the cards are numbered 1 - 10. Whats the probability of drawing a card with the number 1
1/10
After the first card is seen, there are 39 equally likely possibilities for the second card. Yes ?
Okay, what about two cards in a row with the number 1
Why
Because there can't be 2 ones in 10 cards
There's 40 cards
There is 4 of each number
4/40 cuz thersthere's 4 of each
these aren't independent of each other. You will have one less card to choose from. Also you start with four 1s
and total 40
So 1/10?
yea
for atleast for 1
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well its not
What
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I handed in the answer
.
...
waktwait
You opened another channel. Do you have a question?
No
Alright then. Use .close. 
It's continuous
?
@latent dragon
My bad. I didnāt see that.
Lol
Did you want so its 4/40 then 3/39 or just like replace after you get
I have to draw 1 card
it depends first case 0.77
If an experiment has a finite sample space $\Omega$ with $(N)$ equally likely elementary outcomes, then for any event $E\subseteq\Omega$ with $|E|=m$,
Henry Whitmore
$$P(E)=\frac{m}{N}.$$
like just multiply 4/40 * 4/39
Maybe I can withdraw the answer
Henry Whitmore
Ok so far ?
Ok
fGeting twice if u reprepacereplace card iis444
Now I don't know if I can collect it later, let's hope we do well
okay fam, Iām pretty sure they have no idea what those symbols are. Itās not really helpful to bring those up. As lance said, OP is probably just solving an elementary probability problem.
Ok, im leaving this.
0.77 or 0.01
Neither of those are correct for the original question and we shouldn't just be giving answers
If I have to draw 1 time
can you repeat the qs
Then there is also the second draft?
so first get the probability of drawing a card in 40 cards, then you remove that drawn card so we have 39 then find the probability that the drawn card is the same as the one drawn, and just divide the two probabilities
You draw a card from a deck of 40 cards, calculate the probability of obtaining a face card.
So 1/40*1/39?
is it 40 cards or 52 cards?
Normal deck Is 52
yeah but what is stated in the question?
But they say 40 cards though
this one right?
Idk
spanish cards?
It says onlyonly 40 cards
suppose it as Spanish then
Ok
but still dont you have any examples
for which might be the number kfof cards
for it
No
so like there are total of 40 cards and 4 of which is the same face?
Yes
so you were asked to find P(Y|X)?
The peobabiloty
getting twice or after 1 tryung
1
1 time
1/10
yeah probability of getting the same face as the first card drawn
no
š
first find the sample space
so in the first draw there are 40 cards
and you draw one from that
1/40
39
okay so now what is the sample space?
1/39
im asking the sample space
no
Ok
Yes
16/1600
giving 0.01
Nice
1/10 x 1/10
So this Is the answer?
kazkazuhakazuhakazkazuhakazuhakazkazuhakazkazuhakazuhakazkazuhakazuhakazkazuha
wht do u think
so there are 40 cards in the first one and 39 in the second one
Yes
yeayea
so what is the total
79
you multiply it
3/39
40x39
1560
Okay, @gilded gulch imma be real,. I have no idea what you're going on about
1/40 * 3/39
I know 3/1560
now find the favorable outcomes
0,002
so in the first one
you have 4
then you remove 1 in the next one so you have 3
multiplying it youll have 12
Yes
First draw 1: 4/40
Second draw 1 without replacing: 3/39
Multiply: 4/40 * 3/39 = 12/1560 ā 0.0077 (0.77%)
if not then
First draw 1: 4/40
Second draw 1 with replacement: 4/40
Multiply: 4/40 * 4/40 = 16/1600 = 0.01 (1%)
just going from the basics
But I think I have to draw 1 time not 2
now how many faces are there?
4?
Ok
so you multipluy that 10 to 12
and get the probability
So what would the answer be
.
10*12=120
thats the favorable outcomes
120/1560
okay so that is say P(Y) since we are finding P(Y|X)
nannah give ur qs
and P(X) is true regardless
copy paste it
so find the intersection of P(Y) and P(X)
Its wrongš
what answer did you send?
Mind explaining the ping for me please?
Well, in general, we don't give out answers here, but at least from what I've managed to see, it seems as if you haven't really been helping in any useful way @gilded gulch?
im helping hes just not trying to understand it
Seems that it hasn't been too clear though, as per here 
I'm gonna have to ask you to leave OP be please 
thats not a clear basis but yeah okay
YohYou over complicated
just tell me fsvFav
fsvourable outcome
and total outcome
Deck has 40 cards, 4 of each number.
First card: anything.
Second card: 3 cards left with same number out of 39 remaining.
Probability = 3/39 = 1/13.
This then?
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Hello, can someone help me?
Just for future reference, do you mind posting the image/question as your first message so the bot doesnāt pin greetings and requests for help? This way, if the conversation continues for long, helpers donāt have to dig. 
@final apex
Hi
yo
please donāt ping individual helpers.
it's ok I asked him to
oh. Apoligies.
So, let's pick up from yesterday, did you had any idea ?
Itās ok. Dw i shouldāve specified
I canāt really figure it out tbh
So the thing about your book telling you about right neighborhood, is just the same thing as "you don't need absolute value"
if i understand the sentence correctly
So uh let me resend what the textbook said
sure
Write and solve the inequality |f(x) - l| < epsilon, with epsilon > 0.
Observe that, for arbitrarily small values of x, the inequality is satisfied in a complete neighborhood of 0 and, in particular, in a right-hand neighborhood.
Well that makes sense
If that is satisfied in a complete neighborhood of 0
Then itās satisfied in a right hand neighborhood asw
i mean its just logic
right
But how am i supposed to do that
i need to isolate the x
Somehow
maybe i donāt need to solve it with delt
you know the method where you donāt have to use delta?
i can show you an example
lim x->x0 (f(x)) = l
Of course we don't really have to use delta, but I'm guessing that's kind of what you're training with no ?
What kind of class are you taking ?
Can we do both? Iām struggling with both of em
Iām in high school.
Oh okay
That's cool to do epsilon-delta in high-school š
I didn't
anyway, if you want for the epsilon-delta thingy we can break the problem down to two easy problems
Lets do it without delta first
ok
Thatās not normal?
I think that depends on the country and the high school š mine was not really high level anyway, and in france where I was it's kinda rare
yes. I ām from italy, my teacher taught me that but its not on my textbook
So i think youāre not supposed to do it
But my teacher made me learn it anyways
I think that's very good training
So, the usual method to find limit is very simple:
you have a function that's usually like the sum (or the product or whatevs) of functions whose limit you know
I can show you that too yeah
Please, do.
so the idea is this ^ for example here we have
$f(x) = x + \sqrt{x}$
Twenty
Yes
what's the limit of x when x goes to 0 ? (it's not a trap question)
0
Twenty
0
correct
Ok
Now add those up, what's the limit of $f(x)$ when $x$ goes to 0 ?
0
Twenty
yeah, see ? š
but remark that we didn't actually prove that the limit of root of x is 0, we just "know" it, or feel like it's true
and to prove we need the epsilon-delta method
So actually let's do that, we're going to prove that $\lim_{x \to 0^+} \sqrt x = 0$
Twenty
We can do both, let me see
$\lim_{\to 0^+} \sqrt x = 0$
Andrew

Andrew
$\lim_{\xto 0^+} \sqrt x = 0$
```Compilation error:```! Undefined control sequence.
l.49 $\lim_{\xto
0^+} \sqrt x = 0$
The control sequence at the end of the top line
of your error message was never \def'ed. If you have
misspelled it (e.g., `\hobx'), type `I' and the correct
spelling (e.g., `I\hbox'). Otherwise just continue,
and I'll forget about whatever was undefined.
Preview: Tightpage -1310720 -1310720 1310720 1310720
[1{/usr/local/texlive/2023/texmf-var/fonts/map/pdftex/updmap/pdftex.map}{/usr/l```
you should have a space: x \to 0
$\lim_{x \to 0^+} \sqrt x = 0$
Andrew
Ok
So let's break it down
Let $\varepsilon > 0$ be any positive number. We fix it now and we don't change it from now
Twenty
It can be super small yeah, but for all we know it could be anything
no no please interrupt š if you have questions or remark it's ok to interrupt
Okok
So the idea is that we kinda want to "solve" $x + \sqrt{x} < \varepsilon$
Twenty
Yup
The absolute value goes away cuz both x and sqrt of x are positive (x is close to 0+)
Let's break it down this way: we're gonna solve $x < \varepsilon / 2$ on one hand and $\sqrt{x} < \varepsilon / 2$ on the other hand
Twenty
do you agree that, if we solve that then we won ?
Why epsilon/2?
X + sqrtx = epsilon
what computation did you do ? (just checking your reasoning)
Well
x < epsilon/2
sqrtx < epsilon/2
x+sqrtx < epilon/2 + epsilon/2
x+sqrtx < epsilon
šš
so that's the trick, when you have sum of 52 terms, you just solve each term < epsilon/52
yeah i just picked a random number haha
Ok
So
Let's solve
$x < \varepsilon / 2$ on one hand and $\sqrt{x} < \varepsilon / 2$ on the other hand
Twenty
š
Ok
when I say solve, I mean find ONE suitable x that solves both equations
nice, I was expecting that epsilon^2 / 4
now if I ask you to choose only one x, but for which you know it satisfies both equations, what would you do ?
Minimum of epsilon^2/4 and epsilon/2

help im struggling to write that on the chat
Twenty
Yes
that's how you actually find delta in that kind of exercise
So x < $\min(\varepsilon^2/4, \varepsilon/2)$
Andrew
So thats delta
when you have a sum of terms you solve your equations for each term and you set delta to be the minimum
yep
Ok
so we're basically done
because we found $\delta = \min(\varepsilon^2/4, \varepsilon/2)$ which satisfies: for all $x < \delta$, $f(x) < \varepsilon$
Twenty
Ok
so now the interpretation of this is: we did this for any epsilon, without specifying anything
In particular this statement is true for epsilon as small as you want
yep
This
yep
Ok
Tbh i found the āeasier wayā to be harder bc i was trying to do it like this
Was trying to isolate x
Wait is the method i used in this photo correct
Ah and in this picture you should actually look at $|x-1|$ and not just $x$
Twenty
I was trying to get a neighborhood of 1
yep
What do you mean?
I mean that your computation is correct but you need to see that
$-\varepsilon < x-1 < \varepsilon$
Twenty
(i just substracted 1 to your last line)
Twenty
right ?
Yes
so $\delta = \varepsilon$ does the job here
Twenty
I mean, you did all that you needed to do, you just needed that last conclusion ^^
Alright!
to see that $\delta = \varepsilon$ is sufficient, you need that computation of yours
Twenty
Thanks for being patient as well
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can someone explain how to solve these questions using the method shown
i dont understand why you cant do
x - 29/1 - 29
what decides it has to be x - 1 / 29 - 1
why are you given all that
wdym?
its just a horrible way to explain how to do it, theres no explaination
yeah i know
you can but your expression would be equal to 2/(2+5)
you'll get the same answer
wait so it doesnt matter which way it is?
the answer will always be the same?
i understand actually, thank you for your help
the direction you go in still gives the same answer, my teacher just explained it poorly
yes as long as you change the ratio it is equal to
yes thank you so so so much
you should have the same answer
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anyone know what theorem is called and if i can find a video explaining it anywhere?
The books proof is extremely difficult ot undersatand, and im having a hard time understanding (i)
is it just saying there are infinite points of the sequence close to $t$?
BOSS
i don't know that this has a name
yea it means that regardless of the distance you choose you can find infinitely many sequence members within that distance from t
like for example if i take the sequence (1,2,3,4,5) then the subsequence (1,3,5) still converges to 5 but is very much finite
contrast this with the definition of convergence which requires all sequence members to eventually be within that distance
this just says the sequence has to at least have some sequence members sticking around in the neighborhood
infinitely many, not necessarily all but finitely many though
well this isn't really a "sequence" this is more just a finite list
it makes no sense to talk about convergence for finite sequences
sequences are maps from N
Ok yeah just making sure
Ok so for this condition (i)
supose i take $s_n = (-1)^n$
BOSS
have you tried either direction?
mhm
Then we know there is a subsequence that converges to 1 and -1
yes
Yeah im trying them right now for (i)
the for all epsilon is a bit awkwardly placed which is probably leading to confusion tbh
for ii and iii I was curious
i don't like the wording
i guess its consistant with the definition for convergance and cauncy but its all just everywhere rn until i get more practice
if any sequence is not bounded above, lim sup s_n is inf right
Like take $s_n = (-n)^n$
BOSS
This goes to both inf and -inf (limit sup and limit inf )
so is ii and iii just saying we can take subsequneces of this one that go to either inf or -inf becasue its not bounded above or bellow
mind my spelling im on my phone lol
yea it says that for an unbounded sequence you can string together an increasing sequence diverging to infinity
for bounded above
and a similar statement for bounded below
ok but for any normal sequnce, if its not bounded above and its not monotonic, we cant say for certin that it goes to inf
unless lim sup = lim inf
intuitively this should make sense, if we couldnt pick sequence members that get arbitrarily large than surely we must have some ceiling for the sequence
well im not sure what you mean? if a sequence isnt bounded above and not monotonic there are many things that may be true
what goes to inf?
if these are finite then the sequence converges to that value though
could also both be infinite
the limit, im just stating that being not bounded from above, unless the seuqnce is monotonic, doesnt tell us much about the limit
or wondering
yes sorry, basicly if its not bounded above it doesnt nessisarly mean the sequence has a limit of infinity
by inf i meant infinity (forgot there are two terms like that now)
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Hi, I dont understand how this would apply to a sequence such as $a_n = n-1$ where the infimum is defenately 0, but no sub sequence converges to 0
BOSS
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Not made of positive numbers
I assume that's why you closed the channel
yes
I read it a bit more carefully
im guessing this sequence always has to be decresing monotonic if its aproaching 0
Not at all
(2 + (-1)^n)/n is not monotonic
And still converges to 0
given it is monotonic, it must be decreasing ****
Well... yeah sure
The subsequence is said to be monotonic in the theorem, i was just makign sure that its always decresing if a monotonic sequence of positive numbers is approaching 0
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i need to prove that t is alway bigger or equals one
More context?
Because only given this, t = 0 works
Any t greater or equal to 0 works in fact
It's what's written
yes but the question says prove it is in french hold on
i suppose i can solve each side ?
What math module is this? Integrals?
Study both sides
A ⤠B ⤠C
is the study of the signs of B-A and C-B
We can also speak in french if its easier
omelette du fromage
Bruh
actually i rather not english is better thank you tho
is analysis from the french/moroccan/algerian program but they mean calculus i think
The B-A case is a no brainer
Of course
(2+t)² = 4 + 2t + t² is bigger than 4+4t since t ℠0
4+ 4t, not 4+t
And... not obvious anymore
a simple 2nd degree study Sir
The expansion you wrote makes it wrong
4+2t+t² is not bigger than 4+4t. However, 4+4t+t² is...
Anyways what I thought indeed is that they want you to prove this with integral comparison maybe? Since it's in calculus module
would it make sense if we expanded everything and tried to get t alone in the center
hopefully the left side cancels?
But to be honest the polynomial comparison approach is easier
how more details please
Since we know that the denominator has to be greater than 0, you can make two inequalities, then cross multiply through the inequality, then simplify
Well multiplying by (1+t)² is enough
for example, the left side inequality would be 4(1+t) <= (2+t)^2
(before simplifying)
YOOO people sorry for wasting your time it looks like a beast but if you threat every inequality alone both sides simplify to sweet good old t squared
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thank you
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occupy
do you have a question
yes
You don't need to say occupy or anything, just send your question
is there an intuitive way to think about the transpose map? i dont understand why we used the dual space at all for this
it seems so subtle
try playing around with the matrix representation of a linear map T:V->W and the transpose map defined by phi(T) where phi is a linear form in W
It's a way of defining it in which the properties of the matrix transpose become apparent just by the definition of the transpose as a map between dual spaces
I understand the matrix representation will correspond but I feel like I am not really understanding why it is defined this way
why the precomposition
You want a map from dual space of W to dual space of V
If V,W are vector spaces over F, given a map T : V -> W, you want to get a map corresponding to this from W*-> V*. I.e if I give you something say phi in W*, you must give me something in V*, one natural way to do this is by taking phi o T which will give me a map from V to F which is something in V*
Hence the precomposition
is there a geometric interpretation of this
i get the definition in the abstract sense
There is a MSE thread containing more than any one person can explain which you may find helpful:
https://math.stackexchange.com/questions/37398/what-is-the-geometric-interpretation-of-the-transpose
Thanks, I will look into that
I will keep this channel open for a little longer to see if someone else has a view
@winged bobcat Has your question been resolved?
I think I will close it then
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$\frac{sinx \cdot cosx}{cosnx}=six=6$?
Whoops
stop trolling
You could send an image
Have they trolled in the past? Im confused why you sent this. Jc
Richard Mullin
???
because I already knew what latex was going to make
you better get to your point fast
Oh wow

