#help-28
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Word Problem: How many days and MG I have left of my medication.
There are 30 squares of medication in a pack.
Each 1/4 is 15mg. The entire square is 60 mg. Half the square is 30mg.
I am allotted 30mg per day.
20 days have passed.
How many MG should I have left? How many days of treatment should I have left?
Thank you, my brain sucks and I've had the pen and paper out trying to figure this out.
well you eat 30 mg a.k.a. half of a square per day
20 days means 20 * 1/2 or 10 squares eaten
if you started with 30 squares, it means you have 20 squares left -- so these last you 40 more days
@torn jolt
40 doses left thank you
How do I calculate the 40 days into how many 30mg left
Thank you for helping me
So I should have 1200 mg
yes
Thank you so much
@torn jolt Has your question been resolved?
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prove that cos(2a)(1+16cos(2a)cos
2
(4a))=2cos
2
(a)+16cos
4
(2a)cos
2
(4a)−cos
2
(8a)
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part c
doesnt make sense with the graph shown in the solution:
i dont get why theres an asymptote at y = 300
$\lim_{t\to \y} e^{-0.5 t} = ?$
riemann
im not sure i never learnt this
how about limits?
i know that
do you know $e^{-at} = \frac{1}{e^{at}}$
riemann
yes i know this
and when a > 0, then at > 0 for t > 0
yes
what's the limit of 1 / (e to something large) ?
well
?
yes this is 0
ohh ok i understand that now
what if it was
what
wasnt negative exponent like 0.5t instead of -0.5t
you should be able to figure that out
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i need help to explain to solve this please
first i need to plug in 3 to find L which is 5
. close
@obtuse valley Has your question been resolved?
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Hi! I am struggling with letter E. They seem to be both on the right side of the bell curve and I cannot figure out if I should add them or subtract them... Can someone enlighten me? Thanks! ❤️
If you have the cumulative distribution, CDF(x) this is P(score < x).
So if you do CDF(x) - CDF(y) = P(score < x) - P(score < y). This will give you (if x > y) the value P(y < score < x)
Hi
Hi, if you're looking for help, please check #❓how-to-get-help
Oh okay! So to clarify, I need to subtract them? I am not fond with the CDF 😢
yeah
Thank you! Last question! Will it be the same case with letter d?
yeah exactly
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im back with more data management. I got lost trying to figure out how I should continue
use the frequency column
the frequency coloum to find the variance or the standard deviation or both?
both
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$\cos(\frac{x}{2})-\sin(2x)-\cos(\frac{7x}{2})=0$, solve for $x$.
;(
!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
2
Unfortunately, I can't show my work. My phone is dead and I don't have a charger.
So, just suppose I was at 1.
ru sure you there's a closed form solution
Yes, I checked desmos.
i mean i think u can turn the whole thing into a polynomial in cos(x/2)
i know you cant show your work, but you can at least explain what you did (and possibly where you got stuck)
like a 7th degree polynomial?
It's a quintic, in terms of sine. Not a very nice quintic at that.
cos(a)-cos(b) formula, some half-angle shennanigans, (I did prove a solution set was $x=\frac{\pi}{2}k$ for $k\in\mathbb{Z}$) but besides that I have nothing.
;(
well u can factor that out of the quintic
I already did.
Let me see if I can find my worksheet, it's a bit messy so it might take a while to transcribe it.
I was thinking you do the u = x/2 sub then use some trig tricks
Cos(u) - sin(4u) - cos(7u)
-2sin(4u)sin(-3u) - sin(4u)
this works
Then just factorise and solve
you just get 2sin(2x)sin(1.5x) so sin(2x)(1-sin(1.5x))=0
i think its something like that
Yeah that’s where im going
oops mb
@steel solar Has your question been resolved?
I see where I went wrong.
Yeah, made a dumb mistake. I just did $\cos(a)-\cos(b)=-2\sin(a+b)\sin(a-b)$ instead of $-2\sin(\frac{a+b}{2})\sin(\frac{a-b}{2})$. Silly me.
;(
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im confused about this question, how would i solve for any other exclusions?
huh weird
it does work for 7, both is undefined
@raw salmon Has your question been resolved?
can you explain this please, im still a bit confused
when you plug in x=7 in the original expression, it's undefined
on the simplified expression, it's still undefined
so it's still equivalent on x=7
if it's not undefined on the simplified expression, then we'd say that it's not equivalent at that x value
so would the answer be none?
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Check it
No one are answering
You waited less than one minute! Have some patience.
nope
asking in someone else’s channel doesn’t count
u missed a term
Which
Ok
After writing that ncn also we should include
u already inculded that
thats the last term
which is -1
(a+b)^n always has n+1 terms if u expand it
Notes
💀💀🙏🏻
fucking hell
This are my notes
what do u think wud come in the ..... part
3 and 4
eh
That's fine
@somber timber Has your question been resolved?
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I don't have a specific problem, but I'm revisiting integrals on a curve and I'm having a bit of trouble visualizing the concept
I'm used to seeing integrals as "area under a curve", and also integrating wrt time (i.e. integrating velocity wrt time to get displacement), but what's an example of a function that could be integrated on a curve like this, and what would the integral mean?
oh and why can't you just integrate wrt the parameter t, why does it have to be wrt arclength
@narrow seal Has your question been resolved?
for this dont think of an integeral as the area under a curve
an integral is literally just an infinite sum of infinitesimals
literally infinitly adding infinitly small things
here the length of the arc is just the infinite sum of every little infinitly small piece of arc
that helps a bit more, thanks! it's my first time doing calculus in like a year so
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I'm currently a calc student and trying to comprehend continuity better, and #102 on my current homework just has me feeling incapable. If anyone would be willing to give me a nudge in the right direction, it would be greatly appreciated
Thoth
<@&286206848099549185> all i can think is that I can show that g(a) is continuous for some function like just x^2 adn f(x) as like x+1, just at something like a = 0, and complete the continuity checks and call it a day, but I'm worried that's not "proof"
alright yall well I gotta get to bed, any help in the next 6 hours is appreciated
I'm not familiar with what that is 😅 I'm only in calc, and from assuming what that may mean, I wouldnt know how to go about trying to contradict an allegedly guaranteed statement
yes
Assume that f is not continuous in g(a)
I mean, sure, but how would that go to prove that if they both are continuous then their composition will be?
not saying you're wrong, just trying to understand
Wait I wrote it down and then I send it to you
Thoth
could you make it a bit bigger? 😅
I’ll send you the file wait a minute
as long as it's something generic and ubiquitous
Get Microsoft OneNote: https://aka.ms/GetOneNoteMobile
It’s all clear?
If you need any help don’t hesitate to write me directly in chat if you need
$\lim\limits_{x\to ?}f(g(x))$
a^-
Thoth
ah, a
alright
I feel a bit uneasy about my professors reaction to that, but I trust your judgement
To do what?
to submit that as my answer
not verbatim obviously
but the general proof by contradiction
There’s only one truth in mathematics at this level
And there are infinitely many solutions for one problem
fair enough
So if he doesn’t want another approach to same problem he is not a good professor
Anyways I’m also a Calc 1 student
to be fair, she might want something from the textbook, and I've never been great at absorbing textbook material
What do you study that you’re doing Calc without knowing how a contradiction proof works
this is my first year of college
and ee/cs
where would I have learned how a contradiction proof works prior to this, is my question in return, hah
The logic induction proving and contradiction proving are the foundamentals to understand all the calculus theorem
You can’t understand a theorem if you don’t have the tools that allow you to understand it
"covered" is a strong word
a local college as a transfer student to the University of Texas
Ah okay usa that’s normal
:P
I don't much care for the education system here
but c'est la vie
too broke to escape
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Hi
Can i get some help please.
!da2a
No need to ask “Can I ask…?” or “Does anyone know about…?”—it’s faster for everyone if you just ask your question! See https://dontasktoask.com/
Ok anyway
So basically in class we are starting quadratics/parabolas. i know how to use the quadratic equation and complete the square and factorise etc
But then im getting confused on using features of the graph
Like turning point, line of symmetry etc
And the 3 forms of quadratics
So i was wondering if i could get help on stuff like that
do you have an example?
The quadratic relationships is what i need help on the most
Here is an exampl
I done question a wrong
So can we start there please
<@&286206848099549185> its been 15 minutes
Should i delete this conversation?? I think its been forgotten
Oh well. :((
<@&286206848099549185> one last ping, and if not then ill probably ask tomorrow or something
Oh well thanks anyway.
@raven mauve Has your question been resolved?
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How do I simplify this? I know n! = 1* 2 * .. * n * (n+1)*n
look at a_6 for example
$\f{2\cdot2\cdot2\cdot2\cdot2\cdot2}{6\cdot5\cdot4\cdot3\cdot2\cdot1}$
hayley is NOT BRITISH
what about it
the term upwards equals 64
and the top is 2^n
yeah but like
2^n
that is not squared

ratio test goes brr brr
Are you trying to argue that the limit is 0?
Let $n \in \mathbb N$ be fixed first. Then we have $$0 \leq \frac{2^n}{n!} = \frac{2}{n} \cdot \underbrace{\frac{2}{n - 1} \cdots}{\leq 1} \underbrace{\frac{2}{4} \cdot \frac{2}{3} \cdot \frac{2}{2} \cdot \frac{2}{1}}{\leq 1} \leq \frac 2n$$ for $n$ large enough (say $n \geq 5$). Now take limits, then the RHS goes to $0$ and the LHS is $0$, so the limit must be $0$ too.
@marsh wedge
The first factor is 2/n
yes
Everything else we said is <= 1
So that makes the first factor <= than what it is
TeX bot is down..
It is probably mad because I dont understand easy stuff
No it's fine, there surely is an idea behind this and after you get familiar with that you will be able to use it in the future
The argument is that 2/(n - 1) is <= 1 for every n >= 3. Also 2/4 * 2/3 * 2/2 * 2/1 = 2/3 <= 1
So for n >= 5 (or any other big enough n), we have that the whole thing is <= 2/n
It's not and I never claimed that
I'm just claiming that the other factors make the first factor which is 2/n smaller than itself (so are less than 1)
If you multiply any number by something less than 1, it becomes smaller
I'm basically just saying $a \cdot (\text{something something something}) \leq a$ because something something something is $\leq 1$
We can surely say that. As an example, if a = 5 and something something something = 0.8, then surely 5 * 0.8 <= 5 (even strictly less)
What I understood now is that, 2"n is smaller than n! which means the number is getting smaller which means we reach 0
is this the same?
@marsh wedge Has your question been resolved?
Wenn du die Konvergenz nachweisen musst, könntest du es auch mit der Taylorreihe von e^x argumentieren, die für alle R konvergiert
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✅
Okay this I understand
But now how n! can be bigger than 2^n
In my mind ^n makes the number way bigger than n-1
But now how n! can be bigger than 2^n
n! outgrows any exponential
think about it
when you look at 2^n for high values of n, you're throwing more 2's into the product
but for n! you throw bigger and bigger factors into the product
progressively multiplying n numbers is greater than multiplying by only one number n times
so in fact $\frac{u^n}{n!} \to 0$ for \textbf{any} constant $u$ (and $2$ is not special at all here)
ann.in.a.teacup
think of it this way, 2x2x2x2<2x3x4x5 since 2<3,4,5
now extend that to n terms and you have 2^n<n!
note that for big u's it may take n! quite a bit of time to "catch up" to the pure exponential. but once it does, it's already joever
Is there a way to show me maybe an example? 
let's say for 3^n and n!
here's 10^x (red) and x! (blue) plotted on a logarithmic scale. as you can see, x! overtakes after around 25
that works too
there's always a point where rate of growth of exponential is less than rate of growth of n!
or something like that
true
which means n! will outgrow any a^n
Okay this I get, but if I do n-1, n-2… how can it get bigger than u^n
ok like how about this
in terms of n we are always speaking in the LONG RUN
and if you compare n! vs. u^n
fr
where n is much larger than u
then n! and u^n will both be products of n things
but the things that go into n! will be much, much larger than u
For me it only works with n**+** 1
i think you are kind of overthinking it
or maybe you are overthinking the concept of the factorial
That’s what my psychologist always says

i am saying that you are overthinking this one particular mathematical concept
🇼
Yes yes
just think of it as multiplying with only one number n times vs multiplying with +1 number n times
i think there are too many cooks in the kitchen
Okay so I just save in my mind, that n! Is bigger than u^n I think this will work
n! outgrows u^n
the more the merrier
or something
maybe
well
But I feel like there is something missing, I didn’t mentioned a_n = 0
this argument last a while
How do I say „yes this true“ in math language 
a=1
trivial stuff
@marsh wedge Has your question been resolved?
a_n itself is never 0
its LIMIT as n -> +∞ equals 0
Okay we have done a)
but now I did b) have I could do this for a and b?
oh imagine the k´s are n´s. Did this with a youtube video and she wrote k my bad
Yeah you just did the ratio test
realize that $\sum_{n=0}^{\infty} \frac{2^n}{n!}$ actually has a known value
ann.in.a.teacup
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Suppose S is a simply connected open set and 0 does not belong to S.
Is there a unique continuous logarithmic branch on S? (z0 in S, log(z0)=0)
@fresh dawn Has your question been resolved?
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am i leaving out any steps in this proof?
@drifting summit Has your question been resolved?
@drifting summit Has your question been resolved?
@drifting summit Has your question been resolved?
I think it's right. I would say the first paragraph is a bit confusingly worded but maybe that's just me
yeah
this is techicalyl my first upper level math class we're im kinda writing proofs freely
so im always worried about how i wor dstuff
You should probably state what you are assuming for the sake of contradiction first. 'Suppose a < \sup(S), then...'
but what i was trying to say if a < sup S and a is an upper bound it directly contradicts the definition of the supremum
ah
that makes alot more sense
Yeah. I would write
Let a < sup(S). Then a is not an upper bound for S. But by definition of S for all x in S, x < a, so a is an upper bound for S.
You don't really need to do contradiction for that bit to be honest.
ohh okay
You can just say 'for all x in S, x is less than a so a has to be greater or equal to the supremum'.
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Hey yall, I am not 100% fluent in english so my problem is translated originally from my language, but I am not sure if correctly
@dusk zealot Has your question been resolved?
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What intervals does the function increase and which ones does it decrease in
Just look at the graph and write down what parts have the line pointing down and what parts have the line pointing up
@modest spoke Has your question been resolved?
it means x is between -1 and 6
so its the region of the graph bounded by x = - 1 and 6
not including
yes
1 to infinity
because the graphs going to keep going infiniately
also negative infinity to -3
yeah
you can write it as (1, infinity)
(-infinity, 3)
you can have negative infinity and positive infinity
negative is alll the way at the left side of the graph
positive is the right side
sorry its -3
thats where the function is decreasing
at -3 then it starts to go back up
yeah that works as well
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why couldnt the model be V=Ae^kt + B? where B is a constant
because it is not an exponential model then
it does
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what would the domain and range be for this?
The right arrow shows that the function approaches positive infinity
But we have a horizontal asymptote below
So what does that tell you
ye
So our range would be something like -2, infinity
Do you know how to use brackets/parentheses in ranges
wait but it doesnt pass -2 so could it be -2?
it never touches -2
ye ( is for open dot or inf and [ is for closed dots
ye it never touches so why is the range from -2 and not like -1.999999
cuz isnt it where the range starts
there will always be a value closer to the asymptote than the -1.9… no matter how many 9’s you use
that’s why it’s conventional to use the actual number -2
oh oka
i get it now
ty
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Algebra: Polynomials
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might sound dumb but why is the J unit vector for the cross product -J and not +J
that's how determinants work
when you expand a determinant in the top row, it always goes + - + (for cross products and any other type of determinant)
damn how did i miss that in class
so component 2 when calculating determinants is always (-)
not +
i - j + k
yes
appreciate that
$\begin{pmatrix}1&-1&1&-1&\cdots\-1&1&-1&1&\cdots\1&-1&1&-1&\cdots\-1&1&-1&1&\cdots\\vdots&\vdots&\vdots&\vdots&\ddots\end{pmatrix}$
Bonk
wow thats ugly
sure is
ohhhh wait
so if you were gonna do expansion from the 4th row for example
damn that makes a lot of sense
youd start with -1, and alternate
here i thought the + - + thing only applied to 3x3 matrices
i se
e
so its just + - + - + - ...
it also applies to 2x2s, that's why the 2x2 determinant formula is like that
also for 3x3 lets say
is J the opposite sign because cross product finds a vector thats orthogonal to the other 2 vectors
so its a different Y coordinate
and it cant be perpendicular if all 3 directions face the same way as the other 2 vectors
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Vertex formula proof pls
Why h=-b/2a and why k=(b²-4ac)/(-4a)???
And why those numbers will make h and k the coordinates of the vertex?
PLS ANSWER MEE
lets say the quad is y = ax^2 + bx + c
Yes
can you "complete the square"?
stay calm
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lmao emoji change
Yeah but why h and k are also the coordinates of the vertex
wdym?
this is incorrect i think
The coordinates of the vertex are (h,k)
yes
Why is it like that
idk what you mean
nvm its correct
imagine if you discover a(x+b/2a)²-(b²-4ac)/4a
And then how do you know that b/2a can be transformed into -h and the other one into k
Whereas you know damn well that h and k are the coordinates of the vertex
its not that you transform it, you define h to be -b/(2a)
Yeah that's what I mean
How do ppl know that the coordinates of the vertex are (-b/2a,(b²-4ac)/(-4a))
Umm no.
Oh I know that
But I don't really understand how this one works
sure
if you want to move the graph to the right by s units
then you replace x with x-s
and if you want to move the graph up by t units, you add t to the equation
wdym?
Why is moving a graph by s units requires replacing x with x-s
im not sure how to explain it
but ill try
imagine, instead of moving the graph, youre moving the grid
with the axes and origin and stuff
actually
idk
sry
Then I'll just do tests
and want to move it to the right
you transform it to f(x-s)
with s the shift to the right
And to move it to the left it's f(x+s)
yes
now
lets start with ax^2
the most simple quadratic
this clearly has its vertex in (0,0), right?
It's to determine the shape and the direction of the parabola
f(x)=ax^2
Yes
okay, now we shift it to the right by h
f(x-h)=a(x-h)^2
and our vertex follows along to (h,0)
still following?
Yes
great
now we have a(x-h)^2
and we want to shift it up by k
which gives us
a(x-h)^2+k
and once again, our vertex follows to (h,k)
A(x-h)² + k
$a(x-h)^2+k$
Bonk
so, now we have shown that f(x)=a(x-h)^2+k has its vertex in (h,k)
by simply shifting the original function ax^2 up and down and left and right
we have shown that a(x-h)^2+k has its vertex in (h,k)
and also know that we can rewrite ax^2+bx+c into a(x+b/(2a))^2-(b^2-4ac)/(4a)
from here we can find h=-b/(2a) and k=-(b^2-4ac)/(4a)
No need to tell me
I understand perfectly how to get k and h
thus we can conclude that ax^2+bx+c has its vertex in (-b/(2a), -(b^2-4ac)/(4a))
Yes
ik, i just wanted to conclude it fully
(also partly for myself :))
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how am I supposed to do this when they won't give me f(x)?
I've found delta x and gotten the areas of the rectangles but I can't calculate them without the equation for the graph
you are supposed to eyeball them from the graph
wait do they literally just want me to multiply the width of the rectangle with the height for each one
I'm an idiot
.close
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Hi, had a question about a simple calculation.
I can't for the life of me (relearning math) understand why I cannot do
8 / (1/2 * 1/2)
(as in, treat it like a fraction of 8 OVER 1/2 * 1/2 = 8 / 1/4)
as it results in
8 / (1/4) = 32
instead of the "correct" answer of
8 / 1/2 * 1/2 = 8
When we multiply or divide, I assume they carry the same importance, so I can perform 4/2 * 8 = 16 --> 4 * 8/2 = 16
Is this just the importance of working left to right?
When dividing by a fraction you’re essentially multiplying by the reciprocal.
When you're working with expressions like in the picture above it is indeed important to work left to right, this is just because the ÷ and × operators doesn't work so smoothly together, like as you said, (8÷1/2)×1/2 ≠ 8÷(1/2×1/2). What can help is seeing the ÷ always as a fraction, and then calculate always multiplication of fractions that are quite intuitive
8 divided by a half is like 8*2
With multiplication it's legit to do a×(b×c) = (a×b)×c
Yeah
it's called the associative property
compare a + (b + c) = (a + b) + c
but if you replace addition with subtraction or division, it doesn't work
you don't even have a - b = b - a
or a/b = b/a
@cobalt flicker
yes, for subtraction and division it's really really important to work from left to right
it's cause you have a division sign
This.
@cobalt flicker Has your question been resolved?
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for part c, i found the value of x
i dont have access to that document so i dont know the answers, and im not sure what dimensions it’s looking for
but is my working out correct?
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Tu es bloqué ou ?
Je voulais vérifier si ça ça marche attend:
prendre x = 0 pour annuler le premier scalaire puis x = pi pour annuler le scalaire de la fonction identique puis un x quelconque (non congru à 0 ou pi module 2pi) pour annuler le dernier
Ça marche
Ok merci beaucoup
Pour le reste on est d’accord qu’il suffit de prendre une fonction strictement monotone
(Pour montrer que ça n’engendre pas tout f(R,R)
Pour la question 2 ?
Oui
Y a plus simple
Si une famille de 3 vecteurs est libre, une famille génératrice a au moins un cardinal 3
Donc une famille de 2 vecteurs ne peut pas être génératrice
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This isn
oh
This isn't really a maths question, but how on EARTH do you draw a nu without making it look like a u or a v??
$\nu, v, u$ are basically the SAME
$\nu$
Bete Puttigieg 🐢
give it a bit of a flourish
Bonk
Well it ends up just looking like I was trying to draw a v but then I forgot how to write in English
That's a v that's running very quickly to the right. Away from a predator of some sort
I suppose I shall have to do this
I just leave my answers in latex even when I am writing
I make my nus have a floppy bit on the left, us have one on the bottom, and v is just two straight lines
that's not a nu
cuz i drew it shit
looks like a face....this image
Oh my
Certainly
Goodness. X and chi is the other one
(I've no idea why it's pixelated)
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Closed by @rotund ibex
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✅
That psi is truly something
what about it
It's more like a trident
psi is inherently trident shaped
Well yes but I just did it like this
One moment
You seem to have extended it very far
ann.in.a.teacup
$\Psi$
Bonk
I suppose that's how it is
Here are my attempts at zeta and xi
They are also pretty sad
Anyway thanks for your help.
when i first saw someone use this in a lecture i got soooo confused lol
cuz when writing theyre sloppy and if oyu dont know it, makes no sense
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2180
Vad har du testat?
Har inte kommit så långt fram
men började med att få bort nämnaren
i första ledet
yea
Stockholm
Nice, Stockholm also
Skicka gärna bild på vad du gjort
En sekund
I’m studying at KTH
@shy cedarkan jag stryka nämnaren med första täljaren
Om jag förstod dig rätt, nej det får man inte
varför inte
Har lite svårt att visa just nu, men basically för att det är två termer i nämnaren
ska jag också få bort 25
från andra ledet
Aa
@regal gorge Has your question been resolved?
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For what values of 'r' , (4-11r)/12 is an integer. Where r is also an integer.
Please don't occupy multiple help channels.
i'm gonna just close your previous help channel there...
yeah
nothing at all? not even a single value of r that works?
at the very least, if you are really completely dry for ideas, you could tabulate the values of 4 - 11r for r close to zero
i mean yeah i got some... values of r but by substituation... i mean i tried every single values of whole number.. soo its "8"...
so you found r=8 works.
you could notice more generally that $4 - 11r \equiv 4 + r \pmod{12}$ --- which should make it easier to see what the situation is more fully
ann.in.a.teacup
but question says r belongs to intervel of (1000 , 2000)
this is the first time you have shared this with us
how may i find that.. i can't find by substitution everyvalues from whole numbers...
until now i did not know you specifically wanted to find all r strictly between 1000 and 2000
as opposed to just all possible integer values of r
this still stands
unless you know nothing about modular arithmetic and this made no sense to you
yeah i know nothing about that
in which case i will instead say this: $\frac{4-11r}{12}$ is an integer if and only if $\frac{4-11r}{12} + r$ is an integer
anyother method/?
ann.in.a.teacup
and $\frac{4-11r}{12} + r = \frac{r+4}{12}$
ann.in.a.teacup
so at least now you know r has to leave remainder 8 when divided by 12
ok bro
bruh for real???
fr
<@&268886789983436800> this is the third time ive gotten called "bro" by this helpee
after asking him twice not to do that
Do not call people things after they already tell you not to
ohk ohk ohk
If you're kidding, stop kidding
@onyx glen chess match rn?
no.
ok.
@marsh pilot Has your question been resolved?
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I think I almost know how to solve this one but im a bit stuck
whats your question
stuck where
open a new channel then
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I’m pretty lost for this question. Im trying to find a recurrence relation to get the inequality for limsup
But I can’t seem to relate the sup in anyway
are you talking about this part?
Yes
I’m thinking of maybe doing something like s_n = (s_n / s_n-1) * … * (s2/s1)
Or smthing like that
But I don’t think that works out
u forgot a s1
$s_n = s_1 \cdot \frac{s_2}{s_1} \cdot ... \cdot \frac{s_n}{s_{n+1}} = s_1 \cdot \prod_{k=1}^{n-1} \frac{s_{k+1}}{s_k}$
Goëtia
it will
Oh ok so am on the right track then?
I just don’t see how that recurrence/equation relates to sup
what recurrence?
Sorry I mean this equation
just apply ln
This natural log?
yes
Wait wha… so somehow applying natural log makes things work
Why apply ln tho? Shouldn’t it be 1/n?
do s_n ^(1/n)
u will get that 1/n ln sn equal something just try
Ah and then apply natural log?
yeah i think i get $\frac{1}{n} (\ln s_1 + \sum_{k=1}^{n-1} \ln \frac{s_{k+1}}{s_k})$
or smthing like that
what dat
nice
LXDL
maybe i take limit as n goes to infinty now?
ye
but isnt right hand side 1/n ln s_n
whats apcr?
but we wantn limit of s_n ^1/n
ye sry i mean the left hand side,
where we have 1/n * ln (s_n)
no
we dont care bout convergernce now
ye
the condition well just make us get rid of lns1
hmm okay
what?
in other words
maybe i take sup o f$\frac{1}{n} \sum_{k=1}^{n-1} \ln \frac{s_{k+1}}{s_k})$
LXDL
well take n so big that lns1 approx to 0
ye i see that part, but i dont see why we take ln and how this relates to lim sup
wait ill write
i think i am getting $\sup { \ln \frac{s_{k+1}}{s_k} : n \geq 1 }$
LXDL
the problem is that it is only n >= 1 not n >= N
so i cant make a seuqnec of these sups
what r u doin?
oke try this
multiply by s_n
bound s_(n+1)
u get $(L-\varepsilon)^{n-N}s_{N} \leq s_n \leq (L+\varepsilon)^{n-N} s_N$
ye
telescope through it till N
