#help-49
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when you reduce $[U|\vec{y}]$, you end up with four equations:
$$1\cdot x_1 = 6$$
$$1\cdot x_2 = 10$$
$$1\cdot x_3 = 4$$
$$0\cdot x_4 = 0$$
what is the possible value, or values, that $x_4$ could be?
ηασιβ ♥
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I'm kind of struggling with comprehending this question. There are two parts to this question, it seems. I tried to write down as much as I comprehended. If anyone can help out, that would be appreciated.
(Also, to anyone who has seen me before: I mostly ask for help here when I'm about to complete a Khan Academy course, so that's why I'm more active here at the moment)
Okay let's take this step by step
They both have 80 to begin with
Anna invests 20 and Hannah invests 80
They get back r times what they invested
How much do they have after they get it back
Anna has 20r + 60, and Hannah has 80r.
Good
Now they both invest all of their money again
How much do they have after getting back
r(20r+60) for Anna and r(80r) for Hannah?
Yup
20r^2+60r=160r^2?
No
Firstly, don't expand
You'll only confuse yourself by expanding this early
Secondly you want H to have double A
H = 2A
Oh, because we can divide r to both sides!
That would give us 2(20r+60) = 80r.
Thank you so much!
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Struggling on part b
Hi! Here's a hint:
The height of the design is 4m, that should be important...
makes two triangles one above and one below the rectangle right?
i thought of that but i wasnt too sure were to go from there
Welllll
If you form the triangles, you get something like this, right?
yeah?
Well, let me ask you this - why do you need these triangles?
(You do need them, I would just like to know why :)
Wait
it isnt the full side
Right.
But these two are good, you just need to figure out how to use them.
find the adj and then pythag to find red line length
and vice versa for yellow line?
Ahh well you don't need Pythagoras'
uhh i cant see it
I mean, seems like you have the right idea:
Red + Yellow = 4
Right?
So you just need to figure out what the red and yellow ones are
i think i got it
o
so i just find red lines and yellow line and they equal 4
When added together :)
and divide whole thing by two
also could you help on part d
this is my part a and c
Here's a hint: I am going to draw this triangle here
The reason being is because, we want to figure out a triangle that touches the length of h somehowm
What do you know about this triangle?
right angled
Good, anything else?
Good! The question is, where would theta be?
(Try and draw it :)
Perfect.
Now, given this triangle,
How do we figure out the value of h?
4 - adj ?
Perfecto.
okay okay thanks alot!
I'll leave it up to you to continue from here.
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#3
I have a final tomorrow and this is the first time the whole semester I haven’t understood ts
Did you read any Stokes theorem examples
Read these two examples
https://tutorial.math.lamar.edu/classes/calcIII/stokestheorem.aspx
In this section we will discuss Stokes’ Theorem.
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helo
What is their problem man
they told you
From here:
A connected component is a maximal connected subgraph of an undirected graph.
@last slate Has your question been resolved?
because 9 isnt added?
but their wording is weird
”9 can be added and it can still be connected”
is a maximal connected subgraph of an undirected graph
There is no direct connection to it.
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I don't get how the double summation was simplified here
@twilit field Has your question been resolved?
<@&286206848099549185>
By definition,
$$(x_i, x_j)=\begin{cases} 0, & i \neq j \ 1, & i=j \end{cases}$$
Civil Service Pigeon
so, all of the terms vanish except for those where $i=j$
Civil Service Pigeon
which gives $$\sum_i \alpha_i \overline{\alpha_i} (x_i, x_i)=\sum_i \left|\alpha_i \right|^2$$
Civil Service Pigeon
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Stupid question maybe, but let X,Y be two random variables and f,g nonnegative measurable functions. Suppose f(X)g(Y) = f(X) g(Y) holds a.s. What can we conclude about X,Y?
Context; the identity is the result of conditional independence when the sub-sigma-algebra is the whole sigma-algebra, i.e. E[f(X)g(Y) | B] = E[f(X) | B]E[g(Y) | B] and B is a sub-sigma-algebra of A.
if f,g=0 then we can say nothing
so you need stronger conditions on f and g at least
(or f,g constant)
I dont know what kind of conditions those could be
also presumably you meant f(X)g(Y)=f(Y)g(X)?
Hmm, yes. I mean f(X)g(Y) = f(X)g(Y), which to be honest doesn't make much sense to me to say "they agree on a null set". The left-hand side and right-hand side are literally the same function.
You see, if f(X) is in L^1(Ω, A,P) and is B-measurable, then E[f(X) | B] = f(X). So here in the second case, I interpret f(X) and g(Y) to be A-measurable, and so the formula reduces to f(X)g(Y) = f(X)g(Y).
well then it just means that the result is boring
Ok. And there's nothing we can say about X,Y when f(X)g(Y) = f(X)g(Y) (a.s.?)?
like you said, its the same function on both sides
so of course thats just always true
so it means nothing
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And what have you tried?
i can help you
big hint: $y = x$ and $y = -x + 2$ is perpendicular to each other
1 divided by 0 equals Infinity
are you expected to do it with integration?
yes
its from my calc class
oh that is going to be so ass
wym isnt this method correct
its not ass i figured it out (if my integral is correct)
lmao
Compared to other ways of solving it excluding integrals
just tell me if the integration i set up is correct
even if there's no right angle, i can just use heron's formula
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@austere gull
i think we should start all again
also wait what is even happening here
Let's start by letting @austere gull send his questions hers
You can check #math-discussion for that
he apparently just did, or something?
urgh.
i mean the thing is @lusty python the channel is opened in your name
so it's gonna get confusing
The user i pinged is confused on how to factorize a trinomial
but whatever
Someone did the same thing for me in the past tho
This algebra video tutorial provides a basic introduction into factoring trinomials and factoring polynomials. It contains plenty of examples on how to factor quadratic equations.
Algebra Review: https://www.youtube.com/watch?v=i6sbjtJjJ-A
Factoring - Free Formula Sheet:
https://www.video-tutor...
this is very much not how you type that.
4/x + 8/(x+2) = 4
and you are multiplying by x(x+2) on both sides
we are in discord and you will put proper brackets when writing fractions
you got balls saying that
but i mean ok
@austere gull i think that if you are really intellectually gifted as you said we should restart from the basis of math. i can teach it to you if you want
nah, let him shoot himself in the foot
Aight then
ok
play stupid games win stupid prizes
you can go help others tho, if he annoys you then just ignore him
from the private chat
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Hm?
the guy
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How would i solve this?
if f(x)<=g(x) then f(x)-g(x)<=0
factor f(x)-g(x) and find where it is less than zero thus conclude where f(x)<=g(x)
Graphing it gives me that x<1.172...
I think i was supposed to graph it but also it doesnt state it explicitely and i dont know if i shouldve
hi 
That part i do get
But the point is completely arbitrary to the point where it isnt in character with this textbook
what exactly do you mean? 
.w 2x^3+3x^2-2x-5
,w
The exact form of the real root is a long equation but i have literally no clue how i am supposed to get to this value
I think im just gonna pester my teacher to explain this tomorrow

Because wtf is this
Before this, all of our polynomials had nice and elegant factorizations with integers, maybe a fraction or two
,w 2x^3+3x^2-2x-5

,w roots of 2x^3+3x^2-2x-5
wait why did it factor under one cbrt but not the other, what? lmao
Wait! Nope! Its in the answers section of the book!
How in the world is this intentional
damn gotta memorize that cubic formula, it's an important one
it expected you to find this root?
Literally all of our tasks before and this one
She obviously wanted you to get the nested radical expression using the Galois correspondence
lol
so it was expecting you to find a numerical approximation for the root somehow probably
weird
i’m guessing with technology
but still weird
Im so foolish! Why didnt i study undergrad mathematics in middle school?
you're supposed to use graphing calculators ?
Well thatd make it a bit easier wouldnt it
Even the next task explicitly states to use simple polynomial graphs
Probably a typo somewhere
Anyway, thank you for the shared moment of confusion everyone
Patrick Pearse mentioned
Where??
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your name lol
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anyone can spot my mistake ? I've been searching for too long and dont really want to restart but cant find the issue
it should be a stupid mistake somewhere but i cant find
please why am i seeing a plane😭
I dont understand ur 3rd line
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emh
wait give me a sec to make sense of this Im having a couple brainfarts
one step at the time should be the goal with these
well you divided R_2 by 5 to normalize the element in the center, i suppose
yes
ok i see how you got -16/15 brain fart from me
can i not do more than one like thing at the same time though?
cause im adding and minusing the R2 from both which doesnt change
you can do but then it's harder to do a traceback when a mistake happens
ok I see your structure, you wrote the operation next to the matrix, that were applied to, not are going to apply to
yeh idk why I did it like this
or well i dont remember doing too much row operations so this is what i went with
ok the last matrix seems sus
I've done it some different way to double check without the row operations and its wrong thats why I know it should be different
when u multiply R_3 by 16/15
we have a 20 but the -1/3 remained unchanged
or the 4/15
ah
im just gonna redo the right side at the end
i think I may have compleatly fell apart there
hi 
hii
emh
oh ok no
i got it now
is this way good because its easier for finding inverses past 3x3?
cause I usually use some different method for 3x3 which takes so much less for this one for example
sure
whatever you are comfortable with
if u r good generally with row operations then sure continue
I just had to go with row operations cause it told me to do it that way but i hate them tbh
gets so confusing especially since i got mid handwriting
aight anyways thanks
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(a^c)^b
avoid writing a^c^b
Why not just pick up the calculator, assign values, and just check
Maybe he thought this is a bot
i thought it was square..
wdym "square"
oh no, you multiply.
I can prove this with you
but first, do yk that x^n * x^m = x^(n+m)?
(and- if you dont want a proof... that's fine too 
@river robin Has your question been resolved?
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Okay, I went through like 20 linear programming books skimming to see if they have methods for solving sets of inequalities, most nothing close and some close but not, is this even linear programming or does it go by another name? Most were like optimization like max or min, I want the full 4d+ polytope solution, do I have to make my own everything? Is there even a Fourier Motzkin elimination example out now? What math area is this?
I only know simplex
Okay, what teaches that?
Preferably free. X E.
You should see the list of things I went through, haha. X E.
Convex Polytopes and or Polyhedral Theory
Thanks for talking people. X E.
Possibly
what do you mean by
I want the full 4d+ polytope solution
in what form do you expect to get that solution
Okay, I should explain, left side is P+(O-P)z+(X-O)x+(Y-O)y, basically in the form of these three variables from projection. X E.
I don’t think one should used Fourier-Motzhkin in practice because the number of inequalities blows up exponentially.
Not in practice, to know what I am dealing with. X E.
x,y,z I mean, those are scalars, the rest are points. X E.
All valid points will be able to be represented in that, 3 floats only. X E.
This is 4d+. X E.
Right side is, =Q+sum((V_i)s_i). All lower case scalars, upper case vectors here, all scalars unknown bounded except no z upper bound and all points and vectors known. X E.
Man I kind of wish someone could just look for me, contacted a librarian. X E.
I can gaussian eliminate this first, then solve, but still need something to study, sorry. X E.
Should I just let that librarian handle it?
Yeah, the library database is turning up almost nothing useful. X E.
I am on it now. X E.
Should the equation I just gave with s_i bounded and x/z and y/z bounded all with known numbers and z>=1, all with >=, be convex always when cut to be inside the equation space?
X E.*
MLK
Hello people, I am screwed. X E.
hi screwed
All as per one might be maybe or might not be maybe, maybe or maybe not, maybe
I have no clue what this means.
Lots of linear programming, nothing for my problem. X E.
Maybe u r not meant to know
It is a not lying thing. Suffice it to say I am weird. X E.
I would recommend looking up Simplex if you wanna do linear programming
It is about the problem, not necessarily linear programming. X E.
oh mb X E.
mb?
my bad
my bad* X E.
Well, looking up simplex. X E.
Can one perhaps use use z >= 1 to linearise the ratio constraints
Probably. X E.
I am uneducated though. X E.
x increases linearly with z and same for y. X E.
then read more books and stop opening channels every day saying the same thing
Hi riemann, looking for a book, I skimmed like 20 that don't include what I need. X E.
"skimming"
Yes. X E.
i skimmed moby dick. i know how to do whale surgery now
The table of contents is useful. X E.
I have found like one that might help but anyway, just don't know, always check contents before committing to read. You could gain nothing for years otherwise. X E.
Kind of sorry that this is so annoying, should I leave it to that librarian?
The one I contacted. X E.
I still dont know what you are even looking for. you are trying to solve for x,y,z, yes? and you already know some bounds on x,y,z? what result on x,y,z are you expecting as a solution?
this is just pure laziness.
no one said to read for years
Yes, the solution will be planar figures that satisfy everything. X E.
Read one book well, like a month, read 12, a year, if they contain nothing useful to you, why?
the set of solutions (x,y,z) will be some polytope. sure
no one said to read 12 books
in what form are you expecting to get that polytope
True but if I just blindly read books, that is where I end up. X E.
your excuses to not do any reading are also just lazy
I have now found two possibly useful books. X E.
Which ones? X E.
Boundaries, like x,y,z of the planar figures. X E.
but these boundaries will just be other inequalities involving several variables
Orthogonal Sets and Polar Methods in Linear Algebra
Enrique Castillo, Angel Cobo, Francisco Jubete, Rosa Eva Pruneda. X E.
you wont get something simple like 2<=x<=4 or something
True, what I am looking for is all the planes on the outside and the 3 coordinates each point that define them. X E.
https://www.open.edu/openlearn/science-maths-technology/linear-programming-the-basic-ideas/content-section-0?intro=1
This was the other book thing. X E.
This is one book. X E.
I know, I will always be dumb and uneducated at this rate. X E.
Thanks for talking. X E.
youre not dumb
At this point I just want possibilities of solutions, I can think how to optimize later. X E.
Thanks. X E.
By the way, page 200 if you have free online access to the first mentioned book is good. X E.
look, all these kinds of calculations are easy. sagemath can do them for you in seconds
the problem is that I dont get what you are looking for
Can SageMath do inequalities?
yes you can just enter that polytope
and then you can find its vertices or facets or whatever
hi
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!occupied
oops
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What I am looking for is what shapes can a ND cube (calling it cube as in extruded every way), can be cut projected. X E.
Basically like where the ends of the plane are, at least three points per each, and how to define them, unsure, can this be concave?
Anyway, I guess SageMath might be able to but I will need to know how to do this some. X E.
I think it can only be convex. X E.
But need a solution to know and not going down the AI trash dump. X E.
That first book, I think I may just read it, then report back. X E.
the hypercube is convex, i.e. for any two points, the line between them is also in the cube; in particular two points in a slice of the cube will have the line between them is also in the slice and so the slice will also be convex
True, but are their projected forms?
yes
Great, thanks. X E.
Okay, good progress from the math nerds. X E.
Okay, I downloaded the useful book, I will have to read it soon. X E.
Thanks for all the work you put in for nothing in return. X E.
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probability of a 5 card hand from a 52 card deck containing at least one ace
so i first thought 4/52
after that whatever happens may happen so times 1 time 1 times 1 times 1
so final answer 1/13
but does it matter when i get the ace. like is it the 1st card or the fourth.
so i though maybe its 4/50.5?
it is easier to find the complement (probability of no aces)
in terms of not accidentally counting cases more than once, yes, “when” you get the ace matters
but i recommend this
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Hi
I need help interpreting the set representation when it comes to identifying graph isomorphism
Like based off of the given sets how am I supposed to draw the graphs
label A, B, C, D, E with 1, 2, 3, 4, 5 then form a set {n, k} if there is an edge between the two vertices n, k and see what matches
you just need to make sure it has the same edges
Well we need:
Same # edges
Same # vertices
Same degree sequence
And same degree vertex for each corresponding vertex ?
Am I missing something
i didn't say same number of edges
Yes but I’m saying that’s a requirement tho no?
sure but i don't see how this relates to my comment
I thought that is what you were referring to lol
read this again
Yes
Btw how do you know in what order it goes
Like the vertices set
Like do you just assume it goes 1-5
doesn't matter
its just a labeling
what matters is what vertices are connected to what other vertices
Is this correct for checking for isomorphism?
Or is there anything else
i mean you seem to be listing necessary conditions but again im not sure whats confusing about what i said
I mean I was asking for conditions, but I guess I still dont get how to make the correlation between the vertices tbh
I drew the last one
How can I know from this drawing that they are isomorphic
ok lets work with A first
if we label A, B, C, D, E as 1, 2, 3, 4, 5 in that order then what vertices are connected to A (which is 1)
give me the answers in terms of the numbered labeling
3 and 5
are you sure?
We’re doing the first choice right ?
yes. vertex A/1
I see the 1 being with 3 and 5
which vertices are connected to A
is that it?
how many lines are drawn out of A
Oh you’re talking about the diagram ? I thought you were referring to the first option in the multiple choice
3
no lol
yes
so what are the three vertices that are connected to 1
give me the numbered labeling
now do that for all of the vertices
Ohh I see, okay but my problem is with the labeling
How do you know which vertices even correspond to which other vertices from the second graph
well for starters which ones can you rule out immediately
Definitely option 1
Not the same number of edges
So
yea and then you should honestly look at the degree of the vertices in each answer choice
Btw if you look here the final answer is correct but there is no correlation between 1 and 2
you don't actually need to find the correct labeling they want for this
yea because they labeled differently but its really the same thing
they're testing necessary conditions here
So yeah that’s what’s confusing me tbh
Like what are you exactly supposed to check for
can you find the degree of each vertex in our original graph?
label it as a list for me
Degree sequence:
3,3,3,2,1
yea
now do that for the answer choices and see if any of the answer choices dont have the numbers 3, 3, 3, 2, 1
in any order
the third option has a glaring issue too
sorry third
what do you notice about the edge set for option 3?
4 is disconnected
Yup
compare with this
4,2,2,2,1
Yea ur right
So is the whim point to make sure all vertices have the same degree vertex ?
yea they are testing necessary conditions here
option 4 is the only possible answer based on the degrees
as an exercise you might want to identify what each vertex (A, B, C, D, E) maps to
start with the obvious ones
like the vertices of degree 1,2
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Hi can someone please help me understand graph connectivity
the edge connectivity of a graph is the largest number k for which removing k - 1 or less edges from the graph keeps it connected
you kinda just have to imagine deleting edges until you get a disconnected graph for that exercise
What’s up
Don’t say that
I don’t get it bro 😂
a good place to start might be to look for the literal weakest links
Can you describe it in simple words
the vertices with the fewest neighbours
im doing semi pro geometery
a square is 2-edge connected because removing one edge from a square doesn't leave it disconnected, while removing two does
Well I see the weakest links to be 3 edges
an N is 1-edge connected because removing any edge from it disconnects it
So a triangle is 2 edge connected ?
yeah
A pentagon is 2 edge connected also
I see
So we are looking for how many edges we remove that disconnects the graph?
in your graph, you need to look for the maximum number of edges you can remove without disconnecting your graph, and then add one to that number
yup
the minimum number it takes to disconnect, essentially 
Dude idk what’s wrong with me but
I know this is simple
But it isn’t clicking for me
think of it like this
how many edges do we gotta remove to disconnect the graph?
that's what we want to know
3?
3 definitely works, I can't tell if it's the least though
I suspect it is, but I don't know for sure
Oh It needs to be least
yeah
you can sever a vertex with 3 edges from all of its neighbours to disconnect for sure
I wonder if it's possible to only sever 2 edges
nah, there's no way
Then why is my book saying it’s 2
every vertex has at least 3 neighbours, so we can't just cut 2 edges and call it a day, right? 

What do they mean dude
vertex connectivity is the minimum number of verticies we need to remove
Dude I was thinking of edges the whole time 💀
It can be anywhere ?
you can delete wherever you want, sure
if I delete these two nodes, then the graph is disconnected
I was just thinking the same exact thing 😂
I was about to say c and d
Yessir
MS Paint to the rescue 
I'm confident
it can't be more than 3 because we can kill all 3 the edges connecting G to the world to disconnect the graph
I'm about 95% sure it can't be less than 3 because all verticies have at least 3 neighbours
only reason that I'm not 100% sure is that it's been over a year since I did graph theory and I forgot almost everything 
You are right 😁
good luck 
Thank you
you can close the channel if you're done here 
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is there an efficient way to calculate smth like the tens digit of $21^{3^{50}}$?
mmmm7
omg hi
heyy 😭 omggg
euler’s theorem can be helpful
omg hi
what i do for this is crt and euler's theorem
I'd try to see a pattern personally
too slow tho
I apologise for calling you temu layla
,w 21^3
Result:
1.94481e+5
note the nesting
oh i think i see what u mean
,w 21^6
Interesting
I don't feel like proving whether this repeats so that's up to you to do
Euler's theorem blah blah
those were my thoughts exactly kuri
,w table 21^i mod 100 for i = 1,2,3,4,5,6,7,8
mmm pattern
yeah euler's theorem and crt
takes too long
i did it that way
apparently people do this question in 30 secs
Yeah
without a calculator
People be crazy
i’m too stupid for that
also crt and euler is out of scope
No CRT
but i already tried it
Euler took 2 secs

how long would it take for you to compute 21^9 mod 100?
more than 2 seconds
But less than 30 seconds?
well definitely not 2 seconds yep
depends what the stakes are
idk probably not less than 30 seconds either
btw this is from like an elementary algebra class like usual
People whoc an do this in 30 seconds have done many similar questions
😭 would be funny to whip out carmichael, euler, and crt
I don't know why you're saying CRT, but it's not relevant here.
21^n always ends in 1 lololol
is this the pattern we should go for?
binomial bs
yep
1 + 3^50 * 20 + shit divisible by 100...
They know, for instance, that the last two digits are 21,41,61,81,01,… so we only need 3^50 mod 5
u decompose mod 100 to mod 25 and mod 4
hmm i could try the binomial thing too
let me see
,w 3^50 mod 5
Why would you need to do this???
i should go to sleep but @gusty falcon 
Goodnight slayla
goodnight
goodnight 
okay i guess i'll indeed just do what u guys suggested
😭
3^50 (mod 20) then 21^9 mod 100
how did you get here?
3^50 (mod 40) if you want to strictly euler
phi(40) = 16
and bla bla
why is it mod 5?
The last two digits of 21^n are 21,41,61,81,01,… so the cycle length is 5.
So it only depends on n mod 5
😭 okay if you know that then the problem is trivial
wouldn't you take time to figure that out
that's the pattern thing i wrote out here
When a base ends in 1, powers tend to cycle very quickly modulo 100.
That ought to mean you should always try the first few terms as the cycle is expected to be very short.
is that smth you're expected to know?
seems like a random fact
like consider an entirely different example
2^99 mod 99
this one has a much longer cycle
Well, if you think about it...multiplying by something ending in 1 changes only the last two digits in a simple way.
yes it doesn't end with 1
hmm i guess
I mean this is just a completely different type of problem
i mean in terms of cyclicity
simon
how can we know for sure if a cycle is long or short
maybe there's merit trying
a few numbers regardless (?)
i just randomly 😭 typed out mmmm7
that wasn't the inspiration
Well, for general moduli, cycles can be long and unpredictable.. The right method is to use prime factorisation and multiplicative orders, not trial cycles.
sure
You can typically expect to have short cycles when 1. modulus = 10, 100, 1000, etc. 2. modulus is prime. 3. modulus is a power of prime 4. (weak expectation) base ends in 1, 3, 7, or 9 5. base and modulus share strong structure.
For this instance, the cycle length of 2^k mod 99 is the order of 2 modulo 99, and that order is ord_{99}(2) = lcm(ord_9(2), ord_{11}(2)); that is to say, it's not easily predicable.
yeah okay thanks
i guess since this isn't an elem number theory question
it might just always be either 1), 2), or 3)
I suppose
whats the question?
(20+1)^(3^50) congruent to 20*3^50+1 using binom thm
yes
Yeah, that's not faster than 3^50 mod 5
3^50 mod 5 😭 requires you to find the cycle length of 5 too
so it's not just 3^50 mod 5
is it
you cant really escape calculatinglike 4 numbers
41 * 21
nbd at all
Yes
61 * 21
1701
but yeah i guess it's okay
i still think my method is the coolest with the binom thm
once you get here, just find 3^50 mod 5 and then you do 20*4+1 to get 81
your method
is the same as his yeah
but without needing cycle
well i mean you get to 3^50 mod 5 yeah
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I've done the basic stuff
i pulled that 16 outta nowhere so please correct me
and ignore the 16
I think there might not be enough info but can anyone confirm that
I don’t have a pen. I am doing it here:
Alright thanks
Something wrong I need to check again
AAlright
don't forget to find angle LJH
86+a+140+70+27+80=360
(a represent how many angle I turned clockwise when I travel past point x)
a=-43
180-x=43, x=137
answer is C
Clearly I miscalculated first time
This time should be alright
got C as well
I don't even remember learning this ...
I guess maybe this question might be out of my capability
Imaging you are walking along the closed path one cycle
You eventually turned 360 degrees
This is the idea
an alternate method is to recognize the shape as a hexagon
hexagons have 720 degrees
the rest of your job is just finding all the angles
You keep record how many angles you turned at each vertex, add up, being 360
How do I get the A though?
Sorry that's all I don't understand rn
I understand everything else
Can’t help, running
Ah alright
@arctic bronze Has your question been resolved?
What do you mean A?
the a u got here
i know you said this but
idk how you got 43
The angle I turned when I pass vertex x. I don’t know its value, I set it a. In the end it turns out to be -43, meaning at vertex x I actually turned left 43 degrees
By this, adding all angles I have turned (positive for clockwise (right), negative for anti clockwise (left)) will be 360
Ohhh
so basically a is just an unknown? and we get it after adding everything then minusing it with 360
alright tysm
.close
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guys are these tricks useful ? for mental math ?
$(a - b)^2 = a^2 - 2ab + b^2$
1 divided by 0 equals Infinity
Well they made a pretty bad typo here so I'd advance with caution
1 divided by 0 equals Infinity
would this method work for all numbers from 1 to 99 ?
can you explain what's wrong with that please
52 ≠ 52 - 2
so how to correct it ?
,, \def\mm{\mulsymbol}
52\mm9 = (50+2)\mm9
They meant to say this
2 digit works the best
but you can customize your methods
for example, for 3 digits:
$(a + b + c)^2 = a^2 + b^2 + c^2 + 2ab + 2bc + 2ca$
1 divided by 0 equals Infinity
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Hi can someone explain if my logic is correct
I just don’t get why I needed to transpose it for the multiplication to work
sure ill not give ans but help
go on
whats ur problem ur facing
i see ur struggles with chords
its easy
When you build a basis matrix, the rule is: S=[v1v2v3]
If you accidentally write them like the image i gave
then your coordinates won’t multiply correctly.
So you transpose the vectors to put them back into column form, which fixes the multiplication.
@full grail
No but is my answer correct in the first place
Cuz like
THATS what chat gave
And
If it’s correct then the only way to get to that answer is if I transpose the c in standard basis coordinate
<@&286206848099549185>
Can someone help me with this too pls
I feel like the whole multiplication is unnecessary. You know that a a matrix times a vector is a linear combination of the columns, so you can just directly scale the [1, 1, 1] vector with 2, the first element of the [2; 0; 0] vector
The dimensions don't work if you multiply a 3x1 vector with a 3x1 vector
The column dimension of the first matrix (1) needs to be equal with the row dimension of the second matrix (3), which isn't the case
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is this how u do it? feel like smths wrong
Physics problem btw
@edgy crater Has your question been resolved?
Its fine
i feel like you assumed that the masses rebound away from each other with equal speed after collision
which is surely not right
Your assumption that v is same for both masses after collision is false
you need to use energy conservation and linear momentum conservation together
I would just like to say that, try to draw certain instants of the motion
First the instant the mass M collides to the ground
Next i want you to visualise what happens after this very instant
@edgy crater Has your question been resolved?
so small mass up and bigger mass down?
okok, but if v is different then i would have to find another question involving both vs? then simultanous equations?
yah
there are two equations
(or, you should get an intuition for what happens when something really big and something really small collides
i mistook the problem for a similar problem where M >> m, but my responses above (there are two equations) still holds
@edgy crater Has your question been resolved?
Possibly the best hint you could receive
Another would be to approximate terms
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they split the fraction i guess
ye
so
t=sqrt(t)^2 basically
t/sqrt(t)=sqrt(t)
ye
ok
ty
yh
t^1 - t^1/2
yh
u add 1 to the exponent, and then divide by the exponent
isnt that what i just showed you
oh



