#help-19
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it's an identity
do you know identities for cos(90-a) and sin(90-a)?
we can work with that too
yes, i know those
cool
haven't memorised for tan and cot yet
so note that tan(90-a) = sin(90-a) / cos(90-a)
its not so necessary, you can simply derive it using the above
Now plug in the identities you have memorised
okay i see
what will it become?
were you initially suggesting this approach
cos(a)/sin(a)
... which is cot(a)
got it
perfect
you can actuallly leave it in the form cos(a) / sin(a)
makes sense
so we initially had $\frac{\cos\left(a\right)}{\tan\left(90-a\right)}=\frac{\sqrt{3}}{3}$
MethIsAlwaysRight
now it's $\frac{\cos\left(a\right)}{\frac{\cos\left(a\right)}{\sin\left(a\right)}}=\frac{\sqrt{3}}{3}$
MethIsAlwaysRight
because of the newly discovered identiity
yes
it can be simplified a bit more
not really but its actually quite interesting
this is alternative approach by cheby btw
it uses triangle and definitions of trig functions inside triangle
into sin(a) = sqrt(3)/3?
yes
and this is where the problem comes
there is no nice value of a that would make sin(a) = sqrt(3) / 3
yes
so ig you will need to just leave it in form sin^-1(sqrt(3) / 3)
it's not necessary actually
note that the sum of all angles is 180 degrees
yes
one angle is right, that is 90 deg
one angle is alpha, that is arcsin(sqrt3 / 3)
and the last angle is just 180 - 90 - arcsin(sqrt3 / 3)
thats 90 - arcsin(sqrt3 / 3)
woow
it works out
thank you both so much for the help
i hope your pillows are cold both sides lol
yw lol
i close this right?
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im trying to find the solutions for x in
3sinx - 2sinx^2 -1 = 0
sounds like a good idea
it's essentially a quadratic equation
oh I still didn't take quadratics with trig functions, this is the original question
domain is 0..2pi
dw its simple
-2sinx^2 + 3sinx - 1 = 0
now factorize it like if it was a completely normal quadratic equation
imagine that it's -2u^2 + 3u - 1 = 0
(2sinx + 1)(-sinx - 1)
is that right
almost
@tepid pelican Can u tutor me on DMs or call? I need help with my master's thesis defense (Satire)
is it something with the signs
indeed
in the first factor
oh
and in the second too
hmm
what method did you use?
-sinx(2sinx+1) - 1(2sinx + 1)
-2sin^2(x) + 3sin(x) -1
-2sin^2(x) + sin(x) + 2sin(x) -1
i suppose you had it like this, right?
-2sin^2(x) + 3sin(x) -1
-2sin^2(x) - sin(x) - 2sin(x) -1
i had them oppposite signs
oh, thats wrong then
3sin(x) = sin(x) + 2sin(x)
not -sin(x) - 2sin(x)
this method works by rewriting the middle term to something equivalent
so 3sin(x) can be rewritten as sin(x) + 2sin(x)
because sin(x) + 2sin(x) = 3sin(x)
that's like apple + 2 apples = 3 apples
i just thought to myself what two numbers multiply to 2 and add up to -3
so I chose -2 and -1
they actually have to add up to +3
and you'd therefore choose 2 and 1
instead of -2 and -1
isn't -2 - 1 = -3
i probably did something stupid
it is
but they have to add up to **+**3
not **-**3
so you're looking for numbers which add up to +3 and multiply to 2
is that because I had to factor out the negative at the beginning
no
it's standard
the equations were
-2sinx^2 + 3sinx - 1 = 0
or alternatively
-2u^2 + 3u - 1 = 0
now you need to find numbers that add up to the B term (+3) and multiply to a*c ((-2) * (-1))
that's how the method works
it's +b, not -b
ohhh I forgot...
my bad
let me start again
(2sinx + 1)(-sinx - 1)
thats the same
isnt it?
alright so let's look at it together
-2sinx^2 + 3sinx - 1 = 0
we have this
we are therefore looking for numbers which add up to +3 and multiply to (-2)(-1), that is +2
what numbers are these?
yes
so -sinx(2sinx - 1)
so now we have
-sinx(2sinx - 1) + 2sinx - 1
or -sinx(2sinx - 1) + (2sinx - 1)
or -sinx(2sinx - 1) + 1(2sinx - 1)
yup
can you factor that?
+1, indeed
as it is written here
okay so that's basically all
(2sinx - 1)(-sinx+1) = 0
this happens when either of the factors equals 0
so we have 2 equations, 2sinx - 1 = 0 and -sinx + 1 = 0
I'll give you some time to solve them, if you need help ping me
thanks ❤️
I solved the first
sinx = 1/2
x = pi/6
cool
or 5pi/6
yes
hint: try adding sinx to both sides of this
mixed both equations somehow
I see
sinx = 1
yep
mhm
yes
only one in the interval 0, 2pi
so in that interval, there is total of 3 solutions
pi/6, pi/2, 5pi/6
awesome, thank you so much for taking me through this step by step, it was very helpful
you are welcome :]
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is there a way to write P and C in desmos?
i cant find anthing on google
yea yea
probably just use the formulas
who decided a png would be good for this
what is the goal of using combinatorics in desmos?
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I have to calculate the Area of this shape. i used pythagorean theorem to calculate EB and then used the Cosine theorem to calculate BC. Then i wanted to use the Sines Theorem to calculate the Angle ECB but when i do my calculations, the result is wrong. i will not attach my calculations as they are SUPER messy, but you can see my results on the Image.
@subtle perch Has your question been resolved?
@dusk warren
@subtle perch Has your question been resolved?
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hey all! wondering how i can find convergence for this series:
I'm not sure how this server works but my question isn't being solved.
ur question was asked 8 minutes ago
give it another 10
then ping helpers if no one has responded by then
I had 2 ppl respond and they ghosted me, I even asked if they don't know its ok
diverges by ratio test
when we do ratio test, doesnt it end up at 2/3 ?
patience is a virtue
because it ends up as root n ((3-1)/3)
so that would state it converges. no?
It's been almost 20 minutes since I asked
doesnt nth term test work
then @ someone
whats the nth term test? sorry im not familiar with that one
oh divergence test
i think you just called it divergence test
yeah but when we take the limit of that we get indeterminate form no?
the limit is 1 ≠ 0
and l-hopitals would go infinite
this is what i though the limit was just looking at the series
im struggling just putting it on paper
hmm
yup
wonky question
it should diverge anyways so im just putting that down and moving on with my life
now how do we go about solving this one:
i dont think we can use limit comparison here right
unless we can? can we just use e^n for limit comparison?
because it cance;s to 1/ (n^2+1)^3 which is a p-series
i just realized this is a sequence not a series
the sequence converges to 1
yeah
iirc you can only use p-series if it is in the form 1/n^p otherwise you need DCT or LCT
welli kind of goofed in my thinking
bc it would have required LCT anyways
but you can (i think) use DCT here because this series is less than just e^n definitively
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how do I evaluate this? i know it has to do with using log, and i know the square root of 81 is 9, but i don’t really know how to even start
try express everything as an exponent of 3
like this?
ohh ok sorry I just don’t know what to do with the variables
(a^m)^n = a^(mn)
so like this?
sorry but do i simplify it using log? sorry I just don’t really know what to do with the exponents
No you don’t need log
ohhh
Do u agree 3^(12n+8) is the same as 3^(12n) x 3^8
yeah
Then cancel out that -5n wit the 12n
by subtracting 12n by -5n?
oh so 18n?
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Pls help I have a unit test on Friday
What’s confusing you?
@mystic saffron Has your question been resolved?
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The whole topic
Are you familiar with grouping like terms?
@mystic saffron Has your question been resolved?
Yes
Group the ones with variables at the LHS and the ones without at the RHS and make the variable the subject
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I can do these
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im a little confused on the final answer
It asks to find the exact value
Thats what I did
so let’s rewrite the expression in terms of sine and cosine so that we can evaluate them easily
yeah because $\frac{cot(30)}{sec(45)}=\frac{cos(45)}{tan(30)}$
y0shi
not what you have up there
o
ok but either way
i flipped it and now i have
3 (√2) over 2 √3
so does the three and two just cancel out
yep ok i got it ty
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How do I do seperation of variables on this
TayBee
Omg I was factoring it wrong this whole time
I was factoring it as if there was addition between the x and the y
so i was getting like x^2 +2xy +y^2 or sum
oops lmao
Well yes, you might find it becomes a little more simple without the addition shenanigans XD
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yo
9/12 multiplied by 100/1
@lament cargo Has your question been resolved?
do u know how to multiply fractions?
with lesser numbers
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how can i find inverse function of this? the domain is R^2 \ L, where L = {(x,y) | x=0 and y <= 0}
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find all primes $p$ such that there exists integers $a,b \geq 2$ satisfying $p^a-1=5*2^b$.
chloë
@distant flame Has your question been resolved?
<@&286206848099549185>?
!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.
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Can I use power rule to find the derivitive of $y=x^2-3x$
guy
we haven't learned chain rule yet, so we cant use that, but we have learned power rule, so can that be used to find the deriviative of this?
or do i need to use limit deffinition
you can use power rule
first try $x^2$ what do you think that'll be
Jaxx
that would be $2x$
guy
yes now explain to me what you did by doing the power rule
what happened to the power of x
,tex .diff rules
فطر
i subtracted it by 1
and moved the power over to the side
1
so do the same thing now
but my main worry was isnt there a rule for like power rule that you cant do it with something with multiple terms
or something like that?
and thats where chain rule comes in?
not sure
(1)(3)x^0=3
$f(x) + g(x)$ = $f'(x) + g'(x)$
Jaxx
yes
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this is not true
$\frac{d}{dx}(f(x) + g(x))$ = $f'(x) + g'(x)$
Jaxx
there we go

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How do I take the limit
intuitively speaking, n + 1 shouldnt be all that different from n when you are approaching infinity
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how do i find the minimum and maximum values that each variable can take in a augmented matrix?
for example a matrix of
1 0 1 0 1 | 1000
0 1 1 0 1 | 1000
0 0 0 1 1 | 800
0 0 0 0 0| 0
i want to find the minimum and maximum values that each of x1, x2, x3, x4, and x5 can take
<@&286206848099549185>
Are there any other constraints on x1,...,x5? like they are all non-negative or something?
no constraints as far as im aware
i just gave a random example matrix, i just want to know in general how i would find it
i suppose, if you have additional constraints you can just set each variable to the maximum allowed by the constrtaint, like in row 1 you set x1=1000 and x3=0 x5=0, then continue like that, but if there are no non-negativity constraints alongside the given matrix, you could set x1 to be as large as possible and x5 is a free variable so it can be as low as possible so every variable has an unbounded min and max at the moment.
hm ok
ok wait i think the constraints are that the solutions to the equations must not change
yes, the 1000, 1000, 800 are fixed
but for example, i could make x1=1000000, x3=1000, and x5=-1000000, then do some algebra and find what x2 and x4 would be but you can do this for each variable
actually yeah i believe the constraints are that they cannot be negative
that would make a lot more sense, then you look at each variable individually and choose the highest value it can be while still satisfying every equality it is part of
so x1 is only in r1 so you can set x1=1000 which would be its maximum value
same thing for x2
but x3 is in r1 and r2, but both are equal to 1000 so the maximum value for x3 is also 1000
x4 would be 800 for similar reasons, but x5 is present in r1, r2 and r3, where the largest it can be is 800 without violating the constraint from r3
and the minimum for each variable would be 0
alright i think i get what you mean
thanks
@crisp sierra sorry just 1 more thing
for example what if the 1st equation in the matrix was something like 1 0 -1 0 1 | 1000
because im pretty sure the only constraint is that the variable itself cannot be a negative number
correct, so x3 would still be bounded by 1000 from r2, but if i took x3 to be 1000 i could take x1 to be 2000 and x5 to be 0 which would make x2 also 2000 and x4 800
but if you would make the first row -1 0 1 0 1|1000, then you are unbounded since x1 does not appear in any other row
yea because x1, x2 and x4 are pivots and x3 and x5 are free
1 0 -1 0 1 | 1000
0 1 1 0 -1 | 1000
0 0 0 1 1 | 800
0 0 0 0 0 | 0
so the maximum value for x1 is 2000, since i could make x3=1000 and x5=0
the maximum value for x2 is 1800 since i could make x3=0 and x5=800
x3 has a max of 1000
x4 is 800
and x5 is 800
ok but why i cant i just say x1 is 10000, since you could make x3 = 9000 and x5 = 0. now it seems to me that there is no upper limit
since that would break the other equations in the other rows
r3 would not be satisfied in that case
r2 sorry
same thing yea
so we would be saying x2 + 9000 - 0 = 1000, which doesnt make sense
correct since x2 is positive
np
is the minimums all still 0?
sould be if you talk about each value individually
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hi chat
pls help
i tried engineer's induction like i take the sum of the first term, then the sum of the first and second term, the sum of the first second third term, and so on till i find a pattern, and i did not find a pattern
okay chat
then apply difference is squares
show me what you get!! 👁️
like squareroot(a)+squareroot(b) so i multiply by squareroot(a)-squareroot(b)
is that what u meant
i forgot what it's calleddd
conjugate
yes
yes
nothing
😔
bro what
😦
wdym
like
2sqrt(1)/2 - 1sqrt(2)/2
and then factor ig?
and then u see amazing patterns like as noted in color out of space by h. p. lovecraft
@glacial timber Has your question been resolved?
where are u getting stuck?
that’s wild
fr
wat am i doing wrong
?
the answer is this btw
but no solution to learn from
okay
do not merge the denominators
oki
seperate all terms and factor
sry idk what u mean
(2sqrt(1)-1sqrt(2))/2 becomes 2sqrt(1)/2 - 1sqrt(2)/2
which becomes 1 - sqrt(2)/2
this is also known as telescoping I think
so real
i'm uneducated
WOAH
papa
ur smart
ye i found it
tnx
i'll kiss u goodnight
I am fine with this but don’t call me papa pls
okay
mb
are you ok
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Don't mind the spss. hehe
Guys can you please help me?
This seems like a standard question. Was there anything in particular you didn't understand.
Probability and Statistics for Engineering Sciences by Jay L Devore is good reference.
All of them 😭 I didn't understand a thing in online classes
The first thing is know how things are defined
Take your time to understand things
Like conditional probability, what is mean/standard deviation
You can find fully worked solutions on Quizlet
I will leave the rest to you
@hardy verge Has your question been resolved?
@hardy verge Has your question been resolved?
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Is the bottom question 314
I have a test first period and I just want to double check if I’m doing these right
no, show your work
@forest thicket Has your question been resolved?
It’s wrong? Bruh
show your attempt to answer lol
Yesterday I showed the formula I used to get the final surface area but nobody answered
probably did it ata bad time
explain your reasoning/ show wrok again
I can’t
I’m in the car right now on the way to school
And the test is there
Wait what, I did it in my head and it’s right to me still
type your thoughts
and name the propeties you're applying
and not a good idea to do stuff in your head for stuff you're having issues with
Okay so what I think I need to do is add the area of both
Correct me if I’m wrong
of both what
So the area of the cone is 226.67
Both the cone and the cylinder
how are you getting 226.67
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Hello, can someone help me with no. 4?
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I need help
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This is a physics question
When is work done by a spring positive
I know that work is = the change in kinetic energy
Good, using that logic if it is increasing the kinetic energy of what's attached to it, it's doing positive work
Other way to think about it is dW=F.ds
Dot product ^^
If K finial is > K initial then Work is positive
But I guess what I’m asking for is for what position of the spring is work positive
Like if the spring is compressed or stretched
That you can figure out
If it's increasing the kinetic energy
It means it's increasing its speed
Which means its 'supporting' it's motion
This is definitely a better option in this case
Because you can easily relate the direction of force with the position of the spring
Anyway, this logic also works since we know it will apply a pulling force when it's elongated, so when it's elongated AND the block is moving TOWARDS the mean, it will be doing positive work
Or, when it's compressed AND and the block is moving away from the mean, the spring will be doing positive work inthis vase as well
To put it simply, when force and displacement are opposite work is negative
And in what scenario will that happen?
When the particle is going towards the extreme, and the mean has been crossed
What is mean
The mean position
Where x=0
Natural length
Lemme illustrate with a diagram wait
In these two scenarios
We have negative work done
Since velocity is opposite to the dirn of force
Oh i think i understand it now
After being released at the endpoints, extreme, Fs points towards the mean while displacement is positive
Before I was only considering the spring before it was released
Thanks
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what do you do here if i is zero?
can you show original problem
its from the formula for newtons polynomial interpolation
ah
problem is i starts at 0 which means that there is a -1 on top of the multiplication symbol
that thing is defined for i >= 1
so ... what does that mean if the top has a negative?
well i >= 1 means that i - 1 >= 0, so the top is nonnegative
so the $x-x_j$ are indexing through the right points
chebyshev's infinite pee norm
but in the summation, i starts from 0
there's a base case for the basis polynomial for i = 0, n_0 = 1
their notation is misleading though yeah
ahh ok yeah thats what i meant
ill check out other formulas too then
thanks
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My math curriculum sucks, and is horrible at explaining how to graph hyperbolas, if i provide some problems can someone walk me through the steps on how to solve?
rectangular or diagonal
i mean either way the steps are the same
find the intercepts, find the asymptotes, trace through
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Hii
you'd do conservation of energy, since it starts at the top with 0 kinetic, some gravity potential, and some string potential, and at B has speed v, less gravity potential, and less string potential
@forest kayak Has your question been resolved?
@fresh ruin
Please see the marking scheme
They used EPE
AND L ROOT 2
Where did that come from
And in the b part the angle
They used 45
Can you please if possible do that question and send if you know
Thank you
sqrt(2) is at B
that image shows the full solution so just let me know which part looks weird
They used pythagoras
Oh okay
I got the a part
What about the b part
That looks weird
@fresh ruin
They used the angle 45
Idk how did that come
for b you know the horizontal total force must be mv^2/r to go in a circular path, so they write all the forces in the horizontal direction
which is the horizontal component of the diagonal string tension, and the ring normal pushing in some way
Yes
Oh they found the angle from that
Oh okay
@fresh ruin can i add you like in future to ask any questions if i have😅
M3 is like my biggest enemy so🥲
Thanks alot
I got this question now
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I have the following inverse CDF function: N(m, sigma).inversecdf(tau) + tau = v. This function takes tau and returns v, how can I find the inverse of this function, aka the CDF?
In other words, is there a way to solve for $\tau$ here?
$$
N(m, \sigma).inverseCDF(\tau) + \tau = v
$$
LucasYerz
Still trying to solve for $\rho$:
$$
\Phi\left(x\right)=\frac{1}{\sqrt{2\pi}}\int_{-\infty}^{\frac{x-m}{\sigma}}e^{-\frac{t^{2}}{2}}dt
$$
$$
\Phi^{-1}\left(\rho\right)+\rho = v
$$
LucasYerz
is there a shortcut here for trying to take an inverse of another inverse function?
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Where did it go awry? The answer is supposed to be x<0
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Is there a way to solve in a way similar to what I did?
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$\left(\frac{\dd y}{\dd x}\right)^2=(x+1)y$
فطر
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How would you do this? I tried to find the hypotenuse for the second triangle by using pythagorean. After that I found the scale factor but I keep getting 20 for CB but the answer key says it's 15. idk what I'm doing wrong
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I assume there is an easy combinatorial way to count the amount of paths (possibly backtracking) of length 4 from v12 to v14. Could anyone enlighten me?
Paths of any length?
Of length 4
My bad
it is meant to be the dot next to the black dot
sorry
and same with v14
it's the nearest real vertex (all the real vertices are purple)
for any one of the the top or right "diamond" of vertices, there is exactly one path through them
so you can ignore those and simplify the picture a bit
this is not true though, you can go into the center, and then into any vertex of the top or right (or left) diamonds and then into the center and then into the graph we wanted
the paths can be backtracking
There are multiople though depending on what vertices you pick
ok give me one second
can you tell me how many length 4 paths from v_12 to v_14 there are that go through the red vertex?
Just 1 ma'am
so we get 16 paths that hit the center twice
and now need to consider paths that only hit the center once
16 total
huh?
We start at v12
we go to the center
we can go to any other vertex on the graph now
(besides the center)
and then back to the center
and then to v14
there were 16 options to choose from
when we were on the center
and the rest of our choices were determined
so 16 paths that hit the center twice?
yes ok but that wasn't my point
Sorry, what was your point?
it was that we can just count the paths on this graph now that we have the paths that use the ones i blanked out
I think you should now count the number of paths that use one of the V12 K4 edges. Then count the number of paths that use 2 of the V12 K4 edges. Including the ones you just counted (center in/out). I think that’s all your paths
it's not hard to count cases from here
Agreed, but I thought there might be an easier way than counting cases

Is there not
maybe some kind of search but that's not going to be any easier to do by hand me thinks
oh
So I was hoping something would generalize for those
yea there are better ways then
I know that we can take the adjacency matrix
and raise it to a power k to get the amount of paths of length k
in the entries
But
I want to also know the vertices which are in those paths
so I thought that would not be helpful
I can show you what I am trying to compute
yea i know what you're trying to do
You do?
wait you need this?
Yes, see the formula
Summing over gamma paths of length k but then considering a product where vp are the vertices in those such paths
eh idk what that is honestly but if you just need the number of k length paths from v_12 to v_14 for each k it doesn't require anything too fancy
computational nightmare tho
I need the number of paths, but for each individual path I need to know the vertices that are in it
so I can compute that product, since if it hits the center the valence will be different than if it did not
what is the original question

I can explain to you the gist
This formula gives you the resolvant matrix as a function of lambda for some graph
which is equivalent to
(L_G - lambda I )^(-1)
where L_G is the graph laplacian
And, my idea for my sir was that if we have a graph like the one in the image
where the center vertex is weighted very highly compared to the other vertices with uniform weight
that we should be able to approximate the entries in the resolvant matrix, by considering only paths that do not go through the center
as these will get killed off because of their weight being so low
So I'm just trying to work through an example and compare what happens with this
and as such I wanted to approximate the G_(v12, v14)(lambda) for this graph
using this formula
But then I'm getting stuck on computing it because the path shennanigans get complicated
That's my doubt


Do you have any ideas?
Maybe my sir @green elm has ideas
Is P_k the number of paths of length k?
yes
this looks disturbingly like graph theory
Have you done this replacing the K4s with individual vertices? That seems relatively simple since you can ignore the odd paths and might still be a good example of approximating the resolvent matrix.
yes
Also, it seems like you can simplify the counting significantly by counting the number of paths of length n that start and end at the center
That would only be one element of the resolvant matrix though
and we'd still need to compute the others
then you just count how many ways you can get from and to the center
I’m not sure how that would work but I’ll have to look into it
Then the sum splits into the three components for paths of length n=x+y+z. How many paths of length x stay in the first component before going to the center. How many of length y stay and return to the center. How many of length z leave and stay in the second component. This seems to get quite challenging to compute very quickly though, although there might be nice simplifications
For paths starting and ending in the center I think the sum is the same as the number of ways we can sum to y using integers >= 2 (going to any component requires 2 steps) times 4 (for the 4 components)
I’m pretty sure the paths staying in components are 3^(x-1) and 3*(z-1) respectively
x, z being what?
n=x+y+z for paths of length n (for the three components of the path)
From this message
Another potential idea. Call the number of paths of length $n$ that start and end at the center $\gamma$. Then, number of paths of length n from any two vertices $v,w$ (other than the center vertex) is $\frac{\gamma}{16^2}$. This is because we can imagine deleting the first and last edge from an initial path $p$, giving a new path $p’$. Then, $p’$ is a path between $v$ and $w$ if the fist and last edge of $p$ connect to $v$ and $w$. Thus, we divide by $16^2$.
Owen
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hii i need help with question 3 please, the translated text is: Determine the equation of the line inclined to the axis OX at an angle of 135°, which intersects the axis in point (-3.0).
,rotate
<@&286206848099549185>
Hi bro
@acoustic grotto Has your question been resolved?
What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
I don't know where to begin
Hi again
Wooow
Sorry i left you on that last question i asked, i fell asleep 😭
Translation here
Hmm
I have to eat rn, ill see ur msg once i finish, hope that's ok
wait why do you say that x + y = -3
Thats the above question from that sheet i thought that was your problem
Ignore it
Got it ??
Bro i said it here
Yeah
Yk these reduction formulas, for example sin (90+x) = cos x
Yes
so see whenever you see a multiple of pi/2 change sin to cos , or tan to cot or cosec to sec
And keep in mind the sign
And accordingly put it
Wdym multiple of pi/2? Could you give an example?
Whenever you see multiple of pi just think abt the sign
Also I haven't done sec or cosec in school yet
I mean odd multiplw of pi/2
Lik 90
270
450 °
So on
So sin( 90 + x) gives you cos x
pi like 3.14?
Why because sin is positive in 2nd quadrant
I don't understand how 90 is a multiple
No i meant pi radian
180 ° = pi radian
You need to learn all this bro
90 is a multiple of 180 so I have to change sin to cos?
Ohh so it changes only for 90, 270, 450, etc?
And the rest like 180 I keep the same but I just change the signs according to the quadrant?
