#help-23
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How do i find the Rule in function notation for this one?
What do you mean by Rule
@lean otter Has your question been resolved?
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does anyone know of a calculator for if a series diverges or converges with steps?
@pine wren Has your question been resolved?
Just use the tests 
Btw yeah u can use symbolab
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How to do this?
Er mentions something about finding normal vectors but i don’t get how that gets us the ans
And by line l, do they mean the line that always passes through both the planes?
@ebon seal Has your question been resolved?
The idea is that the normal vector $\vec{n_1}$ of plane $\Pi_1$ is orthogonal to $\Pi_1$, and similarly the normal vector $\vec{n_2}$ of plane $\Pi_2$ is orthogonal to $\Pi_2$.\
If the line is contained within \emph{both} planes, then it has to be orthogonal to \emph{both} normal vectors. \
So if you find a vector orthogonal to $\vec{n_1}$ and $\vec{n_2}$, then you have the direction vector of the line.
Azyrashacorki
Man what is orthogonal
Perpendicular
I don’t understand ur 2nd line
Why does that line have to be perpendicular to both normal vectors?
And first of all
This is correct?
Any line in P_1 has to be perpendicular to the normal vector of P_1. Does that make sense to you?
@quiet plume is this correct?
The planes intersect at a line, I don't know what you mean by "always passes through both planes."
It does pass through both planes, since it's the intersection
I don’t understand what line they intersect at
I can’t visualize it
Do u know like a good 3d online tool so i can visualise it?
This is correct
There are three cases for the intersection of two planes.
A bit like how lines in 2D either cross at one point, are parallel, or are coincident(the same).
The planes might intersect at a line, be parallel and never touch, or be totally coincident.
See this Desmos graph with the three cases to get a visual representation of those cases.
If you agree with this, then any line in P_2 is perpendicular to the normal vector of P_2.
Ok wait
Obviously, yes
But if they intersect at a line, then this line must be part of both planes
So in particular, it has to be perpendicular to both normal vectors simultaneously
Yes
Is that the line l?
Yes
Those are arbitrary graphs though they don't have anything to do with the planes in your problem
Ye I understand
So are you good with finding the normal vectors for the plane and then finding a vector normal to both of those?
How do i find the normal vector for the planes tho?
I don’t have a point on the planes
Yes, correct
So dot product=0
Those are direction vectors for the planes
You can compute the cross product of the red vectors to get the normal vector.
But
Does the plane not have infinite direction vectors?
How does a plane have only 2 direction vectors?
I understand we can pick any 2 direction vectors
The plane is spanned by 2 linearly independent vectors.
And do cross product
What does this mean?
It means that yes, you can go in infinitely many directions on either plane, but the point is you can start from the point (2,4,6) and add linear combinations of the red vector to generate all the points on the plane P_1.
Just like you can go in infinitely many directions on the 2D plane, and yet you can write any point as a linear combination of the basis vectors (1,0) and (0,1).
What does ‘add linear combinations of the red vector’ mean?
Azyrashacorki
Ohk
So basically
What ur saying is
U can input any value into theta1 and phi1
Like infinitely many values
And u’ll have all the infinite possible direction vectors
Of the plane
Correct?
Yep
Ok so i got the normal vectors of both planes now
Great! Now compute the cross product of those to get the direction vector of the line
Got it
Line l will have same position vector?
Well it will have to go through the point (2,4,6) since that point is in both planes
And then that direction vector you just found
Yes
Yes
Fuck im getting the direction vector wrong tho
What are you getting?
Lemme try mine again
Oh nvm i got my mistake
Bruv i forgot how to find determinant
How do i compute this again?
I mean I remember we eliminate row and column
But i forgot abt the alternating signs thing
First entry of the first row. You multiply that entry, i, by the determinant of the matrix you get by eliminating the row and column that go through i.
Yeah yeah i got it
Alr bruv i think i got this now
Sorry for wasting so much of ur time
And thank you very much
It's alright it's not like I was stuck to the screen, and even then it wasn't that long 
Good luck in your endeavors
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hi i need help with an algebra equation ; x² + 2x +5 =0
and you have to use the quadratic formula for this. I've done it but i dont think its the right answer im supposed to get
!show
Show your work, and if possible, explain where you are stuck.
,rotate
,rotate 180
4i
another question: how do you do the checking for the answer? to see if its correct and all

You put it back into the expression (x² + 2x +5) and check that it equals what it should equal (0)
@heavy stirrup Has your question been resolved?
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Guys I can't seem to get this right been trying for over a hour
Its finding determinant of that matrix
i get 279 but correct is 99
.close
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I am stuck on this question
It seems very pigeonholey, because of the 2^n + 1, but i couldnt make any meaningful progress
it sounds like you can draw a graph with colored edges, whose vertices are the N cities and whose edges are colored via one of n colors depending on which airlines offer service between the two cities on that edge
haven't seen anything to do with that yet
yep
I was thinking that maybe there has to be a 3-cycle all in one color as well, but the wording makes it sound like it could be ever as small as 5
well like maybe the smallest odd cycle in a single color is of length 5 instead of 3
oh
i was thinking about proving that one of the airline's graphs cannot be bipartite
then it would have to have an odd cycle
that could be good
I was just thinking you could probably show one of them at least has a cycle of any kind
even if it's an even cycle?
it'd be a start, I guess
i dont know how to use the 2^n + 1 information
sorry I still haven't worked it out myself. do we know the number of cycles of odd length in K_{2^n + 1}?
what is K?
the complete graph of order 2^n + 1
so a graph with 2^n+1 vertices and all of its edges
I think it's more than that, because the order in which you choose 5 vertices to make a cycle matters
sometimes
true
@ebon junco Has your question been resolved?
you multiply each N C K by (K-1)!/2?
yeah
I haven't found much joy from that yet
ok I'm starting to have vaguely sensible thoughts
if you do end up having no odd cycles in any of your airlines, then just as you suggested, you can make bipartite representations for your graph, with edges restricted to only one airline
so imagine airline A_i induces a bipartite representation for your graph H_i
we can find the (maximum) number of edges that each H_i can have, and then the complete airline graph will have at least as many edges as the union of all the edges of the H_i's
surely that number must be too small, or maybe too large lol
and by surely I really mean hopefully
if you color every city red or blue, for each airline
for the bipartite thing
then there will be 2^n possible states
so 2 cities must have same coloring on every graph
but that means 1 graph cannot be bipartite
since there are 2^n + 1 cities?
I'm worried because the colorings don't necessarily interact with one another here, right?
thats what im thinking about rn
doesnt it still work?
because if they are WLOG, both blue, then they cannot be connected by that specific airline
and if they are always the same color, they cannot be connected by any of the airlines
ok I've finally caught up and I believe you
the red-blue imagery messed with me a bit because A1's red is different from A2's red
but I see now that there's at least one city that matches another city's parity in every airline
yes, the same pair of cities is always the same color for every airline
my head still hurts from tihnking about it
so every airline A_i induces partite sets V_(1,i) and V_(2,i), so that every city's parity within all the airlines is encoded via some tuple over {1,2}^n
there are 2^n such tuples that each city can be given, but with 2^n+1 cities, there must be a pair of two cities whose parities are encoded via the same tuple by the pigeons
these two cities do not share an edge because they lie in the same partite sets in all bipartite graphs induced by each of the airlines, but this contradicts the graph being complete
well done
thanks for the help!
you did the hard part, very nice job lol
by the way, in case you're curious, this was wrong and did not help at all lol
the total count of edges in each edge-induced subgraph was not generally less than the number of edges in the complete graph
did you do something like N^2/4 * n?
I stuck with N = 2^n+1 and it allowed at most 2^(n-1) * [2^(n-1) + 1] edges in each subgraph
and n times that is generally larger than the total number of edges, being 2^(n-1) * [2^n + 1]
i also tried that earlier
hey well thanks for sharing that problem and baring with me, even though I didn't know the answer or solution path
bearing with me? 🤷
bearing with me
dw, i had spent 3 hours getting nowhere before asking here
it was good to have someone to verify with
the problem was from "The art and craft of problem solving"
nice, thanks for sharing
@ebon junco Has your question been resolved?
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Can someone tell me the where the vertex of the graph lands?
Then I can throw you something that you would never imagine
Just tell me the vertex based on the function given
(0,-5)
I made a mistake shit
lmao huh
I thought if I differentiate it, then I will get 4x - 5
Then the x coordinates of the vertex will be 5/4
Yea, I’m fked up
it happens dw
@west hedge Has your question been resolved?
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Hi guys I really need help with this statistical inference question
my attempt is the first pic, the second pic is the question
I can't figure out whether the red circled formula (inclusion exlusion) is relevant (my attempt at a solution is the 2nd image).
I thought divisions 2 and 3 might have an overlapping bit with the 5 winning numbers, and same for divisions 5 and 6 for the 2 supplementary number bit, but does this mean I only subtract those relevant overlaps and treat everything else the same? or just follow the formula as written there?
<@&286206848099549185>
@slim urchin Has your question been resolved?
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so i found this online
but my uni gives the example of
Let ${X_i} \sim \exp$ with mean $1/\theta$, then $\mathcal I(\theta) = n/\theta^2$
frosst
then it says this
but shouldn't it be $\sqrt{n}(\hat\theta - \theta) \to N(0, \theta^2/n)$
frosst
and then if you want the variance to become 1 you divide by the sqrt of the current variance
so it'll be $\frac{\sqrt{n}(\hat\theta - \theta)}{\frac{\theta}{\sqrt{n}}} = \frac{n(\hat\theta - \theta)}{\theta} \to N(0, 1)$
frosst
I(theta) is a quantity of the distribution not of the number of samples. It shouldn't depend on n I believe
@dull sequoia Has your question been resolved?
@dull sequoia Has your question been resolved?
@dull sequoia Has your question been resolved?
@dull sequoia Has your question been resolved?
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Nguyễn Tuấn Minh
Nguyễn Tuấn Minh
$1 - 3/4 = 1/4$
Nguyễn Tuấn Minh
$1/4 = 8/32 < 8/13$
Nguyễn Tuấn Minh
$\Rightarrow 1 - 3/4 < 1 - 5 / 13$
Nguyễn Tuấn Minh
Nguyễn Tuấn Minh
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Hi, could someone help with this text problem please? I have translated it so if there is something that doesnt make sense pls let me know 🙂
A linesegment runs through point (1,2) and has it's 2 endpoints on the coordinate axes. Determine shortest possible length for the line segment
How did you approach it?
you can write a line as y = ax + b, since the line goes through (1, 2), you can apply that to the formula and get a + b = 2
using this piece of info, you can rewrite the line as y = ax + 2 - a,
its 2 endpoints are on the coordinate axis
so we know its 2 endpoints are (0, 2 - a) and (a-2/a, 0), use the distance formula to write a function that calculates the distance by different values of a, calculate its derivative and solve f' = 0
thank you, I will try!
@upper anchor Has your question been resolved?
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cos(2t) = 2sin(t)cos(2t)
2sin(t) = 1 and cos(2t) = 0
sin(t) = 1/2 and cos(2t) = 0
t = arcsin(1/2) and 2t = arccos(0)
t = pi/6, 5pi/6 and 2t = pi/2, 3pi/2
t = pi/6, 5pi/6, pi/4, 3pi/4
Im not sure what to do next though
Why exactly would cos2t = 0?
Also when looking at the figure it seems to not be right for there to be 4 intersection points
Only 2sint = 1 looks to be the equation for t you are looking for which then just gives you 2 values for t
If you have (x+1)(x+2)=(x+1), your solutions are x+1 = 0 and x+2 = 1, right?
No
You divide both sides by x+1 in this case
Which leaves you with x+2 = 1
And the x+1 is also a solution, no?
What do you mean?
Because it could also be a solution for x... idk this is just what I learned
Am I thinking of something else?
x+1 = 0 would be a solution because x+2= 1 is just the same
Ok I picked a bad example then
Yes
But generally
When we have
$a \cdot b = a$ we divide both sides by a
$a \cdot b / a = a/a$
thijs2725
Which then gives us b = 1
Only notable important thing to remember here is we assume a does not equal 0 here
solution is x
Because we cannot divide by 0
= -1
That was a example xd
This was the question
rhe?
@steep magnet are you still with us?
i need help
with dirichlet's approximation
Open another help channel pls
that would be tiresome
Ok... so we just have t = pi/6 and 5pi/6
Yes
to learn to openchannel
Now just plug those values for t back into your equations for x and y
Could be
We dont know for certain?
Based on intuition it could be true
But you would need the answer sheet to know for certain right haha
But I would think it s correct
Ja
Weet je zeker dat dit dezelfde opgave is haha
Mijn nederlands is niet goed 😝
It doesnt seem like the same exercise haha
Oh oops!!!
This looks like something about triangles
That makes sense why I coudlnt understand it now LOL
So the only point is (1/2, 1/,2), which is our answer, right?
Yes
Yeye that makes sense cause of course y=x goes through (0,0)
Npnp haha
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Fijne dag jonge 😝
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ding dong
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WHat is meant by the initial profile of a PDE?>
ie
@thorny dock Has your question been resolved?
I think it just means the initial condition or the solution at t=0
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I don't understand how it did partial fraction to it
,rotate
@cursive sandal Has your question been resolved?
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can anyone tell me a way of doing this with permutation isntead of picking a number using combination and then arranging it using factorial?
if there isnt a way pls explain why u cant do it iwht permutation
isntead of picking a number using combination and then arranging it using factorial
that's... what a permutation is
(n choose k)*k! = n permute k
yes ive tried solving it with permutation but i kept getting the wrong answer
i tried all the posibilities here
idk if im doing it wrongly
i did (26p2 x 9p1 x 5p1) + (26p1 x 9p1 x....
oh, could u pls explain why?
26p2 x 9p1 x 5p1 is like
ways to pick 2 capital letters for the first 2 characters (where order matters), then a digit for the 3rd character, then a symbol for the 4th character
it does not count passwords of form, e,g, symbol letter letter digit
it's much easier to deal with this by choosing from each character type first then permuting
is there any reason you don't want that?
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Is this how u do it
how could you get x<3?
whyd u changr f(x) bruh?
To its inverse ?
bro ur coeff is -1/2
??
Fhe first equation here is inverse
I’m pretty sure it’s just one
So you don’t elimate the fraction right
Or do u because I did that
@stark yew Has your question been resolved?
.close
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help
whats the dim of P^2
should be 3 if i watch tho the combination
what is a basis
a "combination" of vector dont know how we say it in english
no
its a linearly independent spanning set of vectors
do you know what these words mean
yes
then can you give one example of this
can you give an easy example in the case of P^2
two matrices instead of 4 than
yeah if its was matrices of 1*2 it should be good
ok sure if you also change the space, yes
so I asked about P^2. that space has no matrices
so a basis also cant contain matrices
so whats the point for my question ?
well I am trying to build up some ground from which we can then approach the problem
yeah i understand that its not a basis cuz of not the sale dimension but they asked to found a basis if this one wasnt one
so my question is how do i find a basisi for p2
ow wait
it doesnt help that {x, 1-x^2} isnt a basis either
bruh
you telling me my professor is wrong
translated question: Why can't the following set be a basis for P2? Is this collection generating P2? If not, find a basis and the dimension of the subspace produced by this set.
@peak estuary
<@&286206848099549185>
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Help
What do you need help with?
I was working on this question and I wanted to know why I can't simplify it further. Let me work it out
!original
Please show the original problem, exactly as it was stated to you, with the entire original context. A picture or screenshot is best. If the original problem is not in English, then post it anyway! The additional context might still be helpful. Do your best to provide a translation.
$\frac{3ab+4bc}{2ab}$
UndercoverWasabi
UndercoverWasabi
$\frac{3a+4c}{2a}$
UndercoverWasabi
Why can’t I just remove (don’t know how to call it in English) the a’s here?
because the 4c does not have a factor of a. so you would have to first split it off
Ah thanks
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i am trying to prove the area of an ellipse is pi * ab, why is it negative??? has i ever???
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Hi. I'm struggling with a Lambda Calculus question so I'm hoping I can get some help.
I need to reduce (λz.λu.zu)u(zλw.ww) and I have done so and reached u(zλw.ww) as a normal form, however, I checked interpreters online https://lambdacalc.io/ and https://lambster.dev/ and they reduce to (zu), and I don't understand the steps required to reach that normal form. Any help would be so appreciated, thanks
@magic heath Has your question been resolved?
no <@&286206848099549185>
unfortunately non there
Reduce (λz.λu.zu) u (zλw.ww) to normal form
oh
Lambda calc is something I wasnt taught yet
sorry ig
no worries 🙂 thanks anyways
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what have you tried
put it in between $$
add dollar signs to the left and right
Lizzy
thats a good start
so you want to match coefficients
you have 0n+4 on the left side
and (a+b)n+2a on the right
yup
set a+b=0
you know a
as n varies, you want to make sure both sides are equal
since you have 0n on the left side, the only way for the right side to match is it also have a coefficient of 0 for n
the nth term will cancel out with the (n+2)th term
honestly i think its best to write it out
that way you dont accidentally miss something
if you have a/n and -a(n+c), then the nth term will cancel out with the (n+c)th term
or at least the half of it where they match
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youre welcome
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i need help with absolute values in inequalities. I have three items and I have tried answering them. I wanted to check here if I did it correctly
|x + 9| >= -6
= means is greater than/equal to idk how to write it properly
i came up with (-15,-3)
are you sure its -6?
!original
Please show the original problem, exactly as it was stated to you, with the entire original context. A picture or screenshot is best. If the original problem is not in English, then post it anyway! The additional context might still be helpful. Do your best to provide a translation.
what is the definition of absolute value?
here are the original problems, we were asked to answer them in interval notations
sorry for the bad quality
alright, then this is wrong
tell me this
the positive value of something
yes
so ANYTHING inside absolute value is made positive (well nonnegative in the case of 0)
so when is |x+9| greater than or equal to -6
huh
so what do i do with it?
do you agree by our definition of absolute value that |x|>=0 is always true
yes
there's nothing special about x here. x is a variable, so it makes sense that |x+3|>=0 for all x, |2x+3|>=0 for all x, so on
and if something is greater than 0 is it greater than -6?
-3
are you familiar with how to write all real numbers in interval notation
no
wait, is it 6 or -6
dont mind what I said there, i was talking about the |x| < k = -k < x < k thing so since -6 is my k, when i put it in the -k it became positive
🫎 Moosey 🫎
hmm
Guys I need help
sorry, but you need to occupy another channel 😆
Sorry I’m new
what's next
thats it
for 15
since |x+9| is always greater than 0, it must always be greater than -6, so it holds for all values of x
uhh how do i write the final answer
with this
that's your final answer for 15
infinity and infinity??
(-3,3) is read as 'the interval from -3 to 3, not including -3 and 3
so (-infinity, infinity) is read as the interval going from negative infinity to infinity. This is exactly all real numbers
so whatever real number you put on x it will always be >= -6?
is the solution just like this then?
click for full image
okay this is the issue
erm, is it okay for you to elaborate? i want to learn
we need to think more clearly about the piecewise definition of absolute value of x
does the word piecewise mean anything to you
basically, |x| is defined as x, for x>=0, and -x for x<0
this means that |x+9| is x+9 for x+9>=0 and -x-9 for x+9<=0
i dont have a strong grasp about this, sorry
okay
let's think about it like this then
when does the function inside become zero? Like what x makes x+9=0
-9
so we know that below -9, our function will look like -x-9
and above -9, it will be x+9
hmm
what now
this might help more
okay
maybe it makes more sense if i rearrange it to be |x+9|+6>=0
you see that |x+9| is always greater than or equal to 0, and adding 6 to that won't change that, so it will always be true for any x
i just watched the organic chem tutor's vid and understood it in less than 2 mins 😭😭
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I just need help with these 2 problems I js forgot how to do it
What u did so far is good all you need to do now is solve for x
Use trigo (lol)
Yeah I forgot how to do that 😭
Multiply x?
^
Is that 48 suppose to look like an exponent or did u forget and tried to squeeze it in
I tried to squeeze it in
Yeah so now just divide both sides by sin48
How?
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-12 is right
Yes Steve
what do u need?
tragic
perhaps you should read their solution
That triangle kinda remind me of Mickey
word
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1 = cosx + sinx
what should I do from here?
divide by sqrt2
im confused on why I would do that
to make it smth like sin(x+a)
which trig identity is that
yes
still confused on how i get from sinx + cosx = 1 to sin(x+a)
did you divide
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Can this answer be simplified?
I think you can rationalize the denominator but idk if it makes sense to do that. And idk how i would do that
You could do $\sqrt{\frac{e^x}{\pi}}$ but that's about it
SWR
what swr said is good
also your answer is very slightly wrong
review the steps you took to get your answer
i dont see how? I just substituted my u and a into the formula
a should be a constant in that formula
so then sqrt((pi)(e^x)) cant be a?
correct
yea a is a constant
perform a u-substitution first to make the integral easier to work with
you can factor an e^x in the denominator to cancel a square root e^x
or just do u sub
because the e^x in the numerator will cancel
can you elaborate on this? idk what exactly youre recommending
u=e^x
du=e^x dx
which is precisely the numerator
but don’t use your trig sub formula
it doesn’t work
a is supposed to be a constant
the denominator will be piu-u^2
then from there it should be relatively easy
im sorry, but i dont completely understand this
because piu isnt a constant either
i dont get how to complete the u sub
well that is the u sub
@sudden lagoon
you have to integrate 1/sqrt(piu-u^2)
just complete the square in the denominator
inside the square root
@sudden lagoon Has your question been resolved?
i got 2arcsin(sqrt(u)) / (sqrt(pi))
@severe pond please help this guy
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Hello, I worked out this summation to be the answer to x^n - y^n when x >= y. And I see that it also works for when y >= x. But is there a way to prove it?
Use binomial theorem
And it doesn't seem to be xⁿ - yⁿ
? What do u think it is
Yes, intentionally so
x^n - y^n
How did you know?
.
Separate the yⁿ term and then use binomial theorem
Well yeah, then it becomes (y + (x - y))^n - x^n which is x^n - y^n
I'm wondering if we can prove this using strong induction 
I wondered if you used a different method
Try induction
Well I derived it from using n-dimensional cubes
So it's kinda already proved. Twice, if we consider the binomial theorem too
Uh?
I'm not interested in getting acquainted with strong induction at this time
ok
Well then you're done with it
I can explain how I used n-dimensional cubes if you want
Go ahead
I'm listening
Or rather reading
I first assumed x to be >y
I divided space inside the x^n n-cube on each dimension into 2 intervals: those belonging to the smaller cube and those outside of it. So in each dimensions I divided the big cube into [y] and [x-y].
Considering that each space has n dimensions, there are 2^n different places inside the bigger n-cube that we can sum up and get the bigger n-cube. But I decided to group them into those with the same coefficients. It's done by using (n choose i). Need I explain why? And then it's multiplied by the appropriate dimensions and then y^n is subtracted. Done
What do you think
I don't understand any of that shit considering I'm the dumbest person in geometry
🥲
What's the smaller cube here?
Ok
Why are there 2ⁿ spaces inside the bigger cube (by the bigger cube u mean xⁿ ryt?)
yes, x^n
Because on each dimension those spaces can occupy either the [y] zone or the [x-y] zone
So there are 2 of them
Hence 2^n variations
Ok so your proof is based on that these are all the different points inside the bigger cube but outside the smaller cube 
Not points, but rather subspaces but yes
Yea yea same thing 
How exactly did u select the spaces outside yⁿ
Wdym select
Like how did u come to the fact that those(the original question)are the spaces out side yⁿ
Because x^n - y^n is just the big cube minus the small cube
So all the space of the big cube outside the small cube
ik that
Nvm
Why does the original exp show all the spaces out side the yⁿ cube
?
I might be misunderstanding your question, but are you asking me how I got the expression itself?
Yea how did u arrive to the fact that the no of spaces outside the smaller cube are equal to the expression
Yea, I'm writing that up
tysm

U didn't copy?
looks like il have to wait another half an hour but sure go ahead I'm curious regarding your argument

Thanks 🙂

All the subspaces can be represented as n-elements sequences. For the sake of simplicity let's assume n=4. Then we will have {y, y, y, y}, where [y] can be replaced by [x-y]. The elements of the sequence here represent not only the length in the given dimension but also the specific occupied space, hence if even 1 element is different between sequences then they occupy different space, don't have intersections and are safe to sum up. Here I start summing up sequences(shapes) with different counts of dimensions switched to [x-y], their number equal to i. E.g. i=2 means there are 2 [x-y] elements in the sequence. The dimensions of these shapes will be (x-y)^i * y^(n-i) because, again, the elements are both the specific occupied space and the length in the given dimension. The trick to find different combinations here is to think of the elements in the sequence as of numbers and then use combinatorics. So we have n numbers and the length of the sequence is i because that's how many [x-y] we will have. We get a sequence of numbers which represent the specific occupied spaces in the initial sequence. Then we just find the number of different ones. So essentially the number of combinations also known as (n choose i). Then sum up the variations with different i. That's it
👀
WAIT AHH I GET IT NOW
So u selected the I spaces outside the yⁿ box and multiply then with their dimensions to obtain the given expression so indeed the volume of the part xⁿ - yⁿ will represent the given expression
Hmm but one thing why would we sum up all value of i to get the volume
Because i represents different count of [x-y] in the sequence. And we want to have them all
Because if they are different (and they are, at least because they have different count of [x-y] in them), then they are an unaccounted part of the bigger cube, hence we add it to what we have
Ok i understand
Well atleast from my side the proof seems correct
And this might be the 2nd most elegant proof I've ever seen I'm my life 
This proof is absolutely beautiful
Il suggest to go to Combinatorics channel to see if anyone can find any mistake or something
from my side it's w
Actually I proved the binomial theorem in the same fashion
At least for natural values of n
Damn
come to the dms i would love to see it
It's literally the same, just with a couple tweeks
Ahh so you must have taked a cube of side x+y in the nth dimension and did the same
Yea
nice try to look on google if a similar proof exists
If it doesn't, then what
If not then post your proof
Write a research paper
Ur proof deserves that respect
How do I know if anyone has done this before?
I tried googling but didn't see anything similar. But I might just be bad at googling
hmm ask other senior ppl on the server
Don't show them the proof just state how you have done it
Like using what u have done it
I'm touched

But the proof is already on that sever, can't they just look up my messages?
I think someone has done it before long long before 
https://www.math.brown.edu/tbanchof/Beyond3d/chapter2/section04.html
They've simply counted it up to the 4th degree and haven't provided a way to generalize, no?
And also they haven't done it for x^n - y^n
I'm pretty sure that if they can do it for 4 someone must have did it for n
But il suggest still to post your proove on the web or some where

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want what?
Wlc btw 
If you want to talk to me about something
Ohh ok 
Cya 
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wait help how did they get 6 in this
gelp
Its range of f
you simplified the function to f(x) = x + 3. But the domain is restricted to R - {3}. So, value of f at x=3 should not be in the range
at x = 3, x + 3 = 6
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hello , i am getting two unmathed results for the same problem and i cant get what i am doing wrong in the second way .well i have to find the distance between the point K(-1,2) and the line 4x+3y+12=0 , i can do it by taking the formula |Ax+By+C|/root(A^2+B^2) the result base on that is 14/5, i also thought to solve this like this :i am taking another point of the line the E(0,-4) and finding KE=(1,-6) and then i calculate the projection of KE to the direction vector (3,-4), then using pythagorean theorema
@hollow jewel Has your question been resolved?
<@&286206848099549185>
also i am finding the same with the way i proved the first formula using the magnitude of the cross product
@hollow jewel Has your question been resolved?
<@&286206848099549185>
You can only ping for helpers once 15 minutes after you've posted your question
Anyway, KE is not (0,3)
@desert swallow yeah you are right but still i am getting that the projection is (27/37,-162/37) with magnitude that doesnt match with the other results
You don't need to the projected vector, just its magnitude.
Seems like you divided by 37 instead of 25
Try calculating it again
you are right mate i was doing wrong calculations thanks for your time and sorry i stacked and chatgpt was saying sth about i choosed the wrong point anyways have a good one
.close
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If I have this and want to evaluate the value for k = sqrt(5/3)
i am getting lost along the way
so start off like this
simplifies to this
oh nvm
.close
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Hey guys, does anyone know how to do this? Can someone teach me?
Calculate the equation of a circle: endpoints of a diameter are at (1,5) and (4,3) Thank you!
so you need to find the center and radius
center is the midpoint of the diameter
radius is half of the length of the diameter
yesyes
so what would be the midpoint of line segment between (1,5) and (4,3) (which would be the diameter)
How did you calculate that?
we need to find midpoint of the purple diameter
Ohhh wait sorry its 20
midpointtt
midpoint is a point, it has 2 coordinates
it isnt just 1 number
we need to find the coordinates of midpoint
to find them, note that x coordinate of the midpoint should be the average of x coordinates of (1, 5) and (4, 3)
oooh okayy
same with y coordinate
would it be (3,4)? 😭
almost
3 is not the average of 1 and 4 though
(1 + 4) / 2 is the average
aka arithmetic mean
(2.5,4)
so we now know the center of the circle
now we just need to find the radius
yes
do you know how to find distance between 2 points?
distance formulaa?
yes, that works
btw it will be probably easier to calculate the length of diameter and divide it by 2, rather than calculating distance of the points on circle from the center
if you do it with diameter, you wont have to deal with fractions that much
thank u broo btw sorry if it took so long regarding mine bc this topic is new to me haha
np, it didn't take long, you were quite quick
Im still a little confused abt the radius part thoo 😅
okay
let's calculate the length of the diameter first
ill just repost the pic
okiii
it's the distance between points (1, 5) and (4,3)
i will use this for the distance formula rather than the center numberr?
both would work
im only confused about that part
ohhh
you can use the center if you want to
but you will have to deal with numbers like 2.5
so doing the diameter and then dividing by 2 is probably a bit easier
yesyes it will be correct if i use (1,5) and (4,3) right?
oooh
yes, you just need to divide the diameter by 2 in the end
omg okayy thank you so muchh 🙂
Have you solved it btw?
if so, you can close this with .close
Slr, my final answer is (x-2.5)^2 + (y-4)^2 = 2
hmm the radius looks wrong
ohh mannn
$\sqrt{\left(1-4\right)^{2}+\left(5-3\right)^{2}}=\sqrt{9+4}=\sqrt{13}$
illt ry to find it out, thank you 🙂
MæthIsAlwaysRight
this should be the diameter
bro thank u so much 😭