#help-10
1 messages · Page 447 of 1
did it
but this is correct
And for all next numbers it is 1
Idk how to prove it
And answer also matches accordingly
Yes it maybe correct
@timid silo Sometimes doing most basic thing is most genius thing.
Thanks man
oh
np
even if you compute it we still need an expression for p(n)
and from this P(n) seems to be finite
Yes that's the problem and I don't think its even possible to find expression for a general value of beta
There is something special about given value of beta
there maybe a closed form
I will prove it later
Highly unlikely
hm.. maybe
so you canclose this for now
if you wish
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Restarted this….can someone help me walk through it
Welcome back to “Milo doesn’t get math”
are you familiar with the expansion of
(a-b)(a+b)
Somewhat
what do you think that expands to?
(a-b)(a+b) = a^2 - b^2
is a well known / very common identity for these types of problems
Ideally you won't have to foil every time
apply that to the denominator
Gotcha
As mentioned before, leave numerator as is, in factored form
Sinx • 1 is just… sinx right?
Yes
what's that extra ~ after the sun x,
typo?
Ignore the ~ I forgot it doesn’t cross out on discord
I forgot the cross through command on here
1 - sin^2(x)
the ~ looked like a -
And then….. 1-sinxcosx on top?
no
But don’t you have to multiply
as mentioned before IF you want to expand,
You distribute to both trrms
I have- I was told my original instinct wouldn’t work
I meant about what @high lily is saying
Wdym 😭😭😭
Think about what he’s trying to tell you
Instead of directly jumping
I’m confused on what you’re trying to tell me
I’m just telling you to slow down
I don’t have the time to slow down 🥲
sin^2x + cos^2x = 1is aka pythagorean identity
Yeah I know thank you
It’ll slow you down more if you don’t
Okay listen
True I guess
$\dfrac{a}{b} +\dfrac{c}{d} = \dfrac{ad+bc}{bd}$
robin.dabanc_
Can you prove this lemma
It’s cross multiplying
Are you VERY familiar with this
….no
Im familiar with it I just haven’t used it….a whole lot
I do that times that, and then that times that and boom I get the numerator
Now let’s do the same thing with your two fractions
Identify a,b,c,d and plugin
Right….but why do I do that?
You’ll see
In general if you have two fractions it’s always a good idea to bring it down to one
That’s what I was trying to do with multiplying the top?
Because the RHS you wanna prove is just one thing, and is not a sum, I.e., doesn’t have a +
Am I not supposed to multiply the top straight across?
Yeah but ur tripping
I haven’t even started the top how am I tripping 🥲
In your case can you identify a,b,c,d?
Yeah I guess?
Im not sure what you’re getting at here
I’m trying to understand so I can apply it and do it on my own
different from yesterday it seems
Okay bro go on don’t get distracted
FUCK
Ok ok
Wait but….cosine doesn’t have an extra part
So how do I foil with nothing else
Wdym
yeah but the second thing has two terms
I can’t foil with it if there are only 3 parts can I?
Is that not…the same thing just written differently?
Second is (1-sinx)^2
robin.dabanc_
But d is 1-sinx
??
D is the thing on the bottom in the second fraction
Which, according to your question is cosx
Yeah
I think we’re talking about two very different things
And I think I need to back up
Because I’ve been talking about the second line- this entire time
I’m assuming sinx is meant to be there?
Yea
Ok I’m on the same page now
Yeah my teacher didn’t…foil in any of her examples
I won't say anything about what happened after I left the channel because it might be true that you tried, but I know that while I was there you decided to ignore my questions.
And honestly I did have a way of making this click for you, and I have done it for quite a few people in the past very easily. It seems everyone tries to explain it with this particular example, but obviously all of the other elements hide the underlying concept, which is pretty intuitive once stripped down.
Just my observation, I don't mean this in a rude way or anything and hope you figure it out and wish you the best of luck!
You’re multiplying that with itself
I’m sorry ill do better in the future
Gotcha
So you may distribute it
She just does all the bracket shit in her head so I never remember to write it
That’s why u need a teacher like me
✨
Jk lol
Can you write it out
wait
Yeah one sec
why are we doing (1+sin x)^2
Cross multiplication?
robin.dabanc_
why would we cross multiply here?
ACTUALLY pro tip: don’t expand the denominator
Leave it at cosx(1+sinx)
Because you know you want something to cancel out to the get RHS
to take lcm and blah blah( adding fractions)
Wait
I’m- just gonna ask my teacher on this one I fear
Milo is cooking
Bro you’re one step away
Can you write the numerator now
How am I one step away I have to get to secant
Just wait and watch
It’s my black magic
I need you to keep in mind I’m very limited on the properties I can use- idk if you saw that
I saw it
Ok
If you’re allowed secx = 1/cosx we’re good
So cos^x + 1+2sinx+sin^2x for the numerator
ok i see where (1+sin x)^2 comes from now, numerator
But what about the other parts attached are they not one big thing?
Now that you’ve expanded everything out, they are free terms
you can add in any order
Just keep it at cosx(1+sinx)
Gotcha
2 + 2sinx / cos (1+sinx)
Yes
brackets
Now factor the 2 out
We got what he meant
Factor the 2 out?
still important to at least point out if distribution is something that needs work
2x+2y = 2(x+y)
GOTCHA
It is 😔
Okay thanks
Congrats you’re done cooking
So… 2(sinx +sinx)?
Uh
Is it 2(sinx + 1)?
Not quite
YES
That expands out to 2+2sinx as you see
That means you’re right
Gotcha gotcha
I’m not following
You have 1+sinx in the denominator too
Where did the other 2 go
$\dfrac{2(1+\sin x)}{\cos x (1+\sin x)}$
Right-
robin.dabanc_
=
Where
When you made me do pythag to get rid of sinx^2 and cosx^2
That changed to a 1
And combined with the other 1 from 1 + 2sinx + sinx^2
You agreed till here
$\dfrac{2+2\sin x}{\cos x (1+\sin x)}$
robin.dabanc_
You got this right
Yes
This is the same thing
Notice the BRACKETS
When you expand it out, you get two 2’s
Yes
So it’s the same thing
So this is also what you have right now
Do you get that?
Ok slightly off topic but will you show me how you get the 2 2’s
The 2sinx came from expanding (1+sinx)^2
Right
Mhm
I mean from this
Oh
I know how I got them in the first place
2(1+sinx) you can distribute
robin do you mind if i interject?
so you actually only have a single 2 factor
not two 2's
the reason is because
what you are trying to do when you cancel something from the top and bottom
is you are cancelling a multiplication and a division
Can you explain how it’s cancelling both?
when you had 2+2sin x, yes there are two 2's as written
Because couldn’t I just rewrite it as 2 + sinx +1 +sinx+1 and still have one left over?
but this isnt multiplication so you cant cancel here anyways
do you mean 1 + 1 + sin x + sin x?
because the way you have it written it gives you 3 not 2
I don’t see how that would give me 3-
U missed a 1
Oh yeah I forget that 1 isn’t part of the original term
can you fix that so i know what you mean?
The way it was explained to me- and I’m not saying this is right just trying to give some insight
Is that there are 2 terms of (sinx+1) there
By cancelling- you get rid of one of them and the one on the bottom
Which would leave you with 2 + sinx+1 / cosx
And I’ll be right back I’m being called to the office
Like 5 minutes before anything because I’m not sitting in front of my paper 😭😭😭
milo, do you mind if we put this problem on hold? i believe i have identified the core difficulties you're having in math, but we need to segue and come back to the problem in particular later
if you dont mind doing this, let me know when you get back, ping me so i can see the message
Milo which grade are you in
10th or 9th most prolly
NAH
Wait possible
That’s when most people learn trig
I mean the question is a 10th ncert
I see
Or 8th icse
Are you in 10th too
No
@round island Has your question been resolved?
@round island Has your question been resolved?
btw @round island you are welcome to ping me in #prealg-and-algebra too if you dont feel like opening a help thread if this should close
I’m a junior…..
Can I dm you? I don’t want to lose you in the abyss and you have a…very complicated user
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Can anyone (indian) help with 11th class trigonometry?
sure, ask your doubt
These two
for the (i) part have you studied something like angles in A.P
you can see all the angles have same common difference of 2π/11
Yeah
Jee wale ho to pdhaya gya hoga
New hu 11th pe
acha
Mtlb ek formula hota h pdhaya jayega chapter ke end me usse jaldi hojata hai
Jee wale hi ho na

yes to pdhaya jayega angles in A.P krke i would say tb tk wait krlo
Oo
let me try mai 12th me hu to utna fresh nahi h ye
Oh
@spiral aurora Has your question been resolved?
Oo
cos(theta).cos(2theta). Cos(2² theta)...... Ye formula pdha hai ?
iska product mtlb
this
Simple sum into product lagake solve kroge to end me iska use ayega
i guess you could ask someone else i only know these 2 methods
I don't think there is any other easy method though
Sometimes we over complicate ig
tan(pi/2 - theta) = cot(theta) lagega
this is an easy solution but he hasn't studied it
Its like 3 lines
Ha ye nahi pdha to fir its over
2nd mai vahi lagega
2nd wala maine try nahi kia ab tk
But product me whi lagta h mostly
Complementary
Nahi kabhi kabhi complex number bhi use ho jaate hai
😭😭
@spiral aurora Has your question been resolved?
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what did you try?
ok
so by descarte rule of signs
max 4 real roots exist
then
ik that value at positive inf and negative inf is positive
also the value of derivative stays positive after 1
and value at 1 is 15
so i know it will never be zero there
what do you get when x is negative ?
a rough graph
from negative inf to negative 1 again no roots
i dont get the region from -1 to 0
the derivative is $8x^7 - 7x^6 +2x -1$
parthisjoking
and it will prob stay negative in -1 to 1
when 0 < |x| < 1, what property do you have about x^n
that x^n is smaller than x^n-1
so you might be able to cancel out negative terms
what the helly
yes
i have negative result
positive
since 0 < x < 1, x^8 > x^7
what the helly
noo
<@&286206848099549185> :3
They're not far off.
x^8 - x^7 + x^2 - x + 15 = 0 in 0<x<1 just try some pairings keeping in mind that in this interval x^m > x^n whenever m < n
oh yes i see it
$$P(x) = x^7(x - 1) + x(x - 1) + 15$$
akeanti💕
for $[1, +\infty[$ u will find that $P(x) \ge 15 > 0$
akeanti💕
And then for x > 1 you can do a similar pairing although you've already convinced yourself that there are no roots there
same for $]-\infty, 0]$
akeanti💕
he already treated x > 1
i did this with derivatives
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For the record a pairing that works on (0,1) is x^8 + (x^2 - x^7) + (15-x)
But their method is cleaner
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Yall can someone check my answers
Please don't occupy multiple help channels.
is it the same thing as your other channel #help-6
if it is, please stick to one channel
@echo rover Has your question been resolved?
@echo rover use one channel at a time
@echo rover Has your question been resolved?
.close
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Is there a way to get a function for a= or atleast a way to get a good approximation without specific like stat functions
desmos gotchu
You can find inverse normal distribution and use properties of the probability distribution function
So id take the intergral of the inverse? I don't really understand.
@knotty apex Has your question been resolved?
How would i use the properties to find it. After taking the inverse of the distribution it doesn't look helpful
Do you know what inverse normal distribution is
Google or find a formula in your book and show it
Frick
I did it wrong i think
Yea definitely
I got this. Does this look right? My only concern is that it doesn't go over x=.5
Ill google rq
Idk it looks right but i cant really imagine how you would go from like .68 to the a value
Cuz if u entered an b value of .99/2 it would not be defined on the intergral
Im assuming you divid the orginal answer by two
Plus if you intergral it that max value would be 1 but a can be any number
Idk maybe im stupid cuz actually the intergral would be 0
Cuz its equally on positive and negative
@knotty apex Has your question been resolved?
<@&286206848099549185>
@knotty apex Has your question been resolved?
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ignore the words ik its chem
but im stuck on the math part
although it probably should be easy for me to do but im lowk brain farting or something cuz idk how to multiply everything out lmao 😭 🙏
what are u stuck with? Solving the quadractic?
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guys
can anyone help me with a question
What is your question
just expand the square and compare like power terms to be equal
2nd one can be done by factorisation
or complete square for the left hand side
hint is to expand the right side for part a
lot of green ticks being thrown around
Cuz its correct💯
cant argue against that
what did you do for b)?
$a^2 + b = -6$
parthisjoking
@cyan sequoia Has your question been resolved?
Seems good
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for the note, why is it that "there cannot exists a prime between (a_2,2a_2-1)"?
or is it just wrong :(
doesnt bertrand say that there is only 1 prime in (n,2n-1)
theres atleast afaik
what😭
oh wait its atleast
maybe the note is just about the case distinction of p<=31 and p>32. that prime would take the role of r and then maybe the proof continues the same way
I havent properly digested the proof tho
there will obviously in general be many more than just 1 prime
would be very surprising if there was only one prime between 1000 and 2000
@gloomy vector Has your question been resolved?
@gloomy vector Has your question been resolved?
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Atp just do AxB

?
A cross B
Well I did a+b and then dot product with i+j+k
I guess it isn't the right approach
you want unit vector along a+b
Means a+b/|a+b|
yep
Or simply (a+b) cap
Ok got it
@rose scroll thanks
Got the answer
λ = 1
.close
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Help me find the gradient and equation of tangent line to the graph of f of x = x Sq - 2 at the point (-1,-1)
I jst studied the topic tangent to a curve at a point help me solve the example above
picture please
you learned the derivatives yet?
Ye I learned the first principle and some theorems
1 divided by 0 equals Infinity
and stuffs will get easier
Alr let me find the derivates of the given function
the derivative is basically the gradient of the tangent line
so after you find the derivative, you need to substitute the x coords into the derivative
should get the slope
Suppose if the point was (5,10) I would substitute 5 into the derivates of given function which is basically a slope (gradient) of tangent line
1 divided by 0 equals Infinity
you need to note that
Isn't the deirvate already slope?
but the derivative still has an x in it
so that's why the question asks for the slope at P(-1, -1)
So the deirvate of given function above is 2x
At P (-1,-1)
I substitute - 1
And I get minus 2
Which is the gradient or slope of the tangent line
?
Am I right
Then how do u get the equation of tangent line I got the idea of slope (gradient)
correcto @shrewd plover
now a tangent line
it's just a line
so it's just $y = mx + c$
1 divided by 0 equals Infinity
and you already got $m$, which is your -2
1 divided by 0 equals Infinity
Ye
the tangent line is at P(-1, -1)\
so it also lies on P
so substitute in y = -1 and x = -1
so you can find c
Alr
It's minus 3
substitute m = -2 and c = -3 into the line eq?
In y = mx+c I substituted y =-1 x=-1 these points were given and m was minus 2
Got c as minus 3
1 divided by 0 equals Infinity
sub in $m = -2$ and $c = -3$
1 divided by 0 equals Infinity
-2x - 3
good
yep
Thanks man imma try solve some questions related to it
Bro if the points r not given instead jst x is given
How do u get the y
?
substitute in $f(x)$
1 divided by 0 equals Infinity
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Would someone be able to check my proof for mistakes?
@mighty torrent Has your question been resolved?
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help me out with this integral... I don't know from where to start
hmm, would subbing pi/2 - x help
oh what?
but also an extra tanx down below
simplified tanx + cotx
hmm ic
subsititute dx for d(ln tan x) would make your life better
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For number 28 can someone help me understand the solution for the stack exchange post:https://math.stackexchange.com/questions/649442/ax-int-ax-ft-dt-in-a-b-let-c-in-a-b-if-f-is-continuous-at-c-the
It's using two standard results: if f' exists at c then f is continuous at c, and the fundamental theorem of calculus whoch says A' = f
Ok so I'm not understanding the result of if f' exists at c then f is continuous at c
I don't understand how explanations regarding neighborhoods
@waxen iron Has your question been resolved?
<@&286206848099549185>
This is a theorem that differentiable at x=c then that implies continuous at x=c too
You can prove it using limit definition of differentiable at a point
Oh I see. So $lim_{h \to 0} \frac{f(c+h)-f(c)}{h}=f'(c)= \lim_{h \to 0} f(c+h)-f(c) = hf'(c)$. Since $h=0$ limit becomes $\lim_{h\to0} f(c+h)=f(c)$
BigBen
What about the neighborhoods he was talking about
You cant just make the h dissapear
Can't I set it to 0?
You can't set it to 0 because it's a limit
It likely does not have defined behaviour at 0, and even so it might have different limiting behaviour
Ok but as it approaches 0 that term should be 0
I multiplied both sides by h
You can't multiply both sides by 0
Also the limit is only applied to the definition and not the derivative, so having h f'(x) doesn't make sense
So h would just be a variable that is being multiplied by the f'(c)
So my setup is wrong
?
it's almost there - remember that h is still enclosed in the limit, so instead of multiplying by h, multiply both sides by...
Do you know the definition of continuous?
Ye we can use epsilon delta or we can say that the value of the function at c is equal to the limit as x approaches c
So how can you relate that definition to the one for the derivative
Given they both contain a limit
I don't see what else to multiply by
I'm confused. Are you asking how we can relate epsilon delta to the deirvative and what do you mean they both contain a limit?
The definition of continuous uses a limit
and the definition of the derivative uses a limit
in fairness, it's minimally different to h. recall that
$$\lim_{h \to 0} \frac{f(x+h) - f(x)}{h} \cdot h = \lim_{h\to 0} \frac{f(x+h) - f(x)}{h} \cdot \lim_{h \to 0} h$$
so what are you actually multiplying by?
حسیب ♥
so try and use the derivative definition to show the continuous definition
Wait is there any need to multiply by anything anymore isn't what you wrote equal to $\lim_{h\to0} f(x+h)-f(x)$
BigBen
it is, but i wanted you to see that we are multiplying by $\lim_{h \to 0} h$, not $h$ as a variable
حسیب ♥
in fact, $\lim_{h \to 0} h$ is very much constant and is equal to 0
That limit is resolvent and just has value 0
حسیب ♥
oh lol
You have to very careful if you want to combine or seperate limits
Wdym
if you're asking me: you wrote $$\lim_{h \to 0} f(x+h) - f(x) = hf'(x)$$
when it should have been
$$\lim_{h \to 0} f(x+h) - f(x) = \left[ \lim_{h \to 0} h\right] f'(x)$$
حسیب ♥
and you do have to justify this step a bit more: how do we know that $\lim_{h \to 0} f(x+h) - f(x)$ exists?
حسیب ♥
Well we end up getting that it is equal to 0. If the limit approaches a definite value it must exist
this is not always true. $\lim_{x \to 0} \frac 1x$ approaches a definite value, 0, but the limit doesn't exist
حسیب ♥
but the reason we know $\lim_{h \to 0} f(x+h) - f(x)$ exists is because of a certain property of limits
حسیب ♥
any ideas which one?
sorry i should clarify: the limit is absolutely equal to 0 and this is how the proof goes, but the justification isn't quite right
How can this be? If the limit doesn't exist it doesn't approach a value
oh whoops x2, i thought you meant that since x approached a definite value, that the limit existed
what you said is true, but how do you know that the limit approaches a definite value?
Not sure I would just use epsilon delta to show that we have a limit
Because we have that the limit is equal to the limit of h as h approaches 0 times f'(c) which is just 0
right, and how do we justify this multiplication?
We sub in f'(c) for the limit defintion of the derivative
we do, and then we apply the product rule, which is important to mention
i'm being pedantic, but we do have to justify that the limits we are working with exist at every step
Right so we apply the product rule of limits and then sub in for the limit defintion of f'(c)
thus we get $\lim_{h \to 0} f(x+h) - f(x) = 0 \iff $\lim_{h \to 0} f(x+h) = \lim_{h \to 0} f(x) \iff \lim_{h \to 0} f(x+h) = f(x),$ which is a definition of continuity
حسیب ♥
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https://math.stackexchange.com/questions/649442/ax-int-ax-ft-dt-in-a-b-let-c-in-a-b-if-f-is-continuous-at-c-the so in regards to the answer given in this post is he saying that if f'(c) is continuous for some interval of c+- delta and then in that interval we can apply the above logic
yeah, the chain here is
f' continuous at c
=> f differentiable around c
=> f continuous*
=> A' continuous (since A' = f)
* is where our little proof comes in
Can you elborate on the point around c
The implication is not two way
f' being continuous at c implies that f' exists for a bunch of values around c, which means that f is differentiable for all those values
From the definition of continuity we get $\lim_{x -> a} f(x)-f(a) = 0$
WeAreIngram
Sorry I'm not seeing this implication
multiplying by $1 = \frac{x-a}{x-a}$ we get
WeAreIngram
$\lim_{x->a} \frac{f(x)-f(a)}{x-a} (x-a)$
WeAreIngram
Then we use the multiplicative property of limits to say that
$\lim_{x \to a} \frac{f(x)-f(a)}{x-a} (x-a) = \lim_{x \to a} \frac{f(x)-f(a)}{x-a} \lim_{x \to a} (x-a)$
and the last limit is known as equal to 0, so the whole expression is 0
That is, when the left limit is defined
Thus requiring the differentiable condition
use \to
ren (@ if replying)
$\lim_{x\to a}$
@pure geode I'm having troubling see the interval around c
WeAreIngram
The interval definition is equivalent to the $\lim_{x \to a} f(x) - f(a) = 0$ definition
WeAreIngram
How?
fair! if f' is continuous around c, then for |x-c| < δ, we have |f'(x)-f'(c)| < ε (assuming all the necessary assumptions and what have you). this means that, for values of x that are δ away from c, f'(x) has to not only exist, but be ε close to f'(c). so we end up with f' existing in an ε neighbourhood of f'(c)
Look at the similarity between the formal definition of the limit and the definition of continuity
actually, you can say that, since f' is a function, f' is defined for every value on [a,b]. then you can say that, since [a,b] is sufficiently "nice" (i.e. doesnt have any holes, is connected, compact <=> closed and bounded), that f' exists in a neighbourhood of f'(c)
i.e. it follows independently from the fact that f' is a function and it's defined on the entirety of [a,b]
If you mean by epsilon delta. The are very similar just the statement inside the absolute value is slightly different
But don't we have that f' is cotnious at c
sorry, im still talking about this question
I'm confused. Didn't the the guy say f' continuous at c though?
yes? so we have f' continuous at c, then we have that f is differentiable, then we apply the argument above to get that f is continuous at c
I just want to clarify that our neighborhoods that we are getting is because there are x values that are at most sigma+c or sigma -c. And f' is continuous for all of those
Meaning that for each of those f' points we can show that f is continuous
By what we did earlier
i'm saying that f' exists at all of those points. f' existing at a point is the definition of differentiability, so i just want to argue that f is differentiable
but i want to argue its differentiable in a neighbourhood to avoid any problems. although it might be a bit overkill
you have the right idea, though. our neighbourhoods are dictated by δ and ε, and f' exists within the ε neighbourhood (the δ neighbourhood corresponds to x-values, not f(x)-values). so we can say f' exists around f'(c)
i.e. f is differentiable in a neighbourhood of f(c)
Ok so f is continuous for all those f' in the epsilon neighborhood
exactly! and then of course f(x) = A'(x) by the fundamental theorem of calculus (I), so we are done
the original question is a really good foundational question to understanding all the interactions between differentiability, continuity, integrability, etc. etc.
in fact i've seen a similar question on a university final exam
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$C(n)$ is the number of reachable configurations of an $n \times n \times n$ Rubik’s Cube.
rozehip
Is this correct? $$
C(n) =
\begin{cases}
1 & \text{if } n = 1 \
\displaystyle \frac{(8! \cdot 3^7) \cdot \left( \frac{24!}{(4!)^6} \right)^{\lfloor \frac{(n-2)^2}{4} \rfloor} \cdot (24!)^{\lfloor \frac{n-2}{2} \rfloor} \cdot \left( 12! \cdot 2^{11} \right)^{n \bmod 2}}{(24 - 23(n \bmod 2)) \cdot 2^{n \bmod 2}} & \text{if } n \ge 2
\end{cases}
$$
rozehip
It matches the first few examples on OEIS: ```
1
3674160
43252003274489856000
7401196841564901869874093974498574336000000000
282870942277741856536180333107150328293127731985672134721536000000000000000
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Is this the correct proof for13?
Would I just need to separate them out into their own inequalities to fix it?
yeah
|f(x) - L| < epsilon for 0 < |x-a| < delta1 and similarly for g(x)
also you should mention what L is somewhere (maybe add = L to the 2nd line with lim f = lim g)
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Can someone explain to me the mistake i did. I learned the proof for formula partial integration. I did it in an other way that should be correct but i get the formula but with extra stuff?
What was the original question
It's just messy to cancel dx's like that
It’s a proof we started from d(uv) and the proof followed from there
Yes but what are you trying to prove
Partial intzgration formula
integration by parts?
Yes
Well i cancelled the dx’s on the first one and it still gave me the formula 🤷♂️
Yes but you're collapsing du/dx dx to du, which is fine if you think about u-substitution
If you do it with your second method you're integrating 1-forms which you do without appending dx's, but that's beyond calculus
What is the final formula you're trying to show
Have you tried integrating both sides of the product rule
They did that twice just with two different ways
I'm confused about what precisely is happening because it reads like youve already done it
They have, but they're wondering why their second way of doing it has extra dx's appearing after integrating both sides wrt dx
Im confused sorry english isnt my first language i dont know what u mean
In short, avoid stuff like df/dx = dg/dx -> df=dg because you're dealing with differentials and that's harder to justify at this level
Well i just tried it in an other way it shouldve given me the same thing but it didnt
You can do $\int \frac{\dd{f}}{\dd{x}} \dd{x} = \int \dd{f}$ because while it looks like cancelling $\dd{x}$, you're really using the substitution $u = f(x)$.
Azyrashacorki
I have no clue what ur talking abt
What does substitution have to do with this
Can u maybe add extra steps 🥲
If you have $\int \frac{\dd{f}}{\dd{x}} \dd{x}$, by setting $u = f(x)$ you get $\dd{u} = \frac{\dd{f}}{\dd{x}}\dd{x}$, so $\int \frac{\dd{f}}{\dd{x}} \dd{x} = \int \dd{u} = \int \dd{f}$.
That's just using substitution
So du=df/dx but dont u get integral (du dx ) ? How do u get integral du after substituting
Azyrashacorki
In your second method you end up with $d(uv) = d(u) v + d(v)u$, which is fine in some sense, but then you'd have to integrate in a different sense than "integrating w.r.t. x".
Azyrashacorki
Yea i dont get it
This is confusing
I just dont see how that substition correlates to my problem
Or how else i’d have to integrate it instead of wrt x
What I'm saying is that the first method is easier to justify through substitution
Well is there anything i can do to make the 2nd method work too
Both are the same no?
All i did was cancel dx’s in first method before integrating both sides and 2nd method i cancelled the dx’s after integrating both sides
You could salvage it by writing $u=u(x)$ and $v = v(x)$, so that $\dd{u} = \frac{\dd{u}}{\dd{x}}\dd{x}$ and $\dd{v} = \frac{\dd{v}}{\dd{x}}\dd{x}$.\
Then $$u(x)v(x) = \int \frac{\dd{(u(x)v(x))}}{\dd{x}} \dd{x} = \int v \frac{\dd{u}}{\dd{x}} \dd{x} + \int u \frac{\dd{v}}{\dd{x}} \dd{x}.$$
Azyrashacorki
The point is it's messy if you argue by treating derivatives as fractions.
And while your first method does that too, it's easier to justify it.
So the 2nd one is technically wrong?
Kinda. It's just clumsy
Essentially you sort of just have have to integrate both sides (as in just stick an integral sign out front without appending dx's) when you deal with differentials like that
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The sum of the radii of the inscribed and circumscribed circles of a right-angled triangle is equal to one of the legs. Find the acute angles of the triangle.
what have you tried
The center of the inscribed circle lies at the intersection of the bisectors
And described on the hypotenuse, dividing it in half
can you draw it out
so you try to find the 2 acute angles?
Is there something wrong with my construction?
Oh my god, it's 45 degrees there
I just miscalculated
its a square isoceles triangle
Is that right?
Since this is a tangent, it is perpendicular, but it is a median, so the triangle is isosceles. The rest is just calculations
correct
or you can just show the two triangles are similar then show isoceles
then find angles
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no worries
<@&268886789983436800>

thanks mods
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Help pls
Moderators beat this guy up
It sounds as if this is a new user who is confused about a particular meme question
They have posted lots of AI stuff and multiple troll questions
they posted AI stuff in the previous thread that was linked, but I haven't yet seen evidence of multiple troll questions
also to the moderators, this user tried to help in 23 using AI as well.
they shall feel the my wrath
and it's not against the rules to post AI shit as "this is stuff that I've tried, I don't understand it, can someone else help explain."
They posted about riemann zeta in 3 channels
just thought it would be useful context.
They posted AI to try and help someone
no that's the other guy
they appear to have been banned for 1 + 2 + 3 + 4 + ... days
Wait
good one
waow i didn't know you can ban for negative days
try using the riemann zeta function
that is indeed a problem
and even argued when i tried to warn them
i suppose they will have come back 2 hours ago
This guy knows analytic continuation
what are they like owner now 
thanks for backing me up 🔥
accept my fq pls
?
its a matter of belief really
click Report Spam
.close
Closed by @brazen viper
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what r u guys doin here
I was just looking for help but ok
Chatting
Sorry
math
check out #❓how-to-get-help
send your question in #help-47
shoudlnt u only help here and not chat???
No-one to help
it's already been handled
That was unnecessary asf
people can get a little bit spammy when something interesting happens.
this channel will lock or refresh soon enough
Sorry queen, why you direct to dm advertising like that tho?
.and then someone will be left with their name on it because they were silly 
ill definitely remember those words to counter hanako's argument
hmm
Cuz I'm trying to beat this toxic person who i considered a friend as a kind of achievement
i sent a suggestion about it and no one accepted 🥀
She is spreading misinformation about me and is taking my insecurity to her advantage
@inner sierra what is so funny
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Any idea on how to dolce this expression?
Consider log rules with the fact that 2^3 = 8 and 2^5 = 32.
Like this?
Yeah
so now I use the power rule correct?
<@&268886789983436800>
ok solved
.close
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Hi idk how to get the pr length i think it's gonna need the phytagoras formula but i couldn't find the ps nor the pq
what is OQ
It's 5 cm
what's QP
yes so SO
It's 10 cm
SO = OQ - SQ
good idea to draw on this circle if u can
to keep track of all the lengths
Yes
@blissful sequoia Has your question been resolved?
yes you need pythagoras
first draw OR and consider RSO right angle triangle and use pythagoras to get RS as sqrt(21)
OR is radius btw = 5cm
now in RSP right angle triangle SP=7cm,RS=sqrt(21) you can find RP using pythagoras
Sorry but could u re explain the RS part? Idk what sqrt is
Square root
@blissful sequoia Has your question been resolved?
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