#help-17
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@indigo wave Has your question been resolved?
no, i didn't ecieved any help.
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If 3x−y=12, what is the value of 8^x/2^y?
A) 2^12
B) 4^4
C) 8^2
D) The value cannot be determined from the information given.
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
Start by writing 8 in base 2
mark it
aka 2^3
so then it turns into (2^3)^x/2^y which is the same as 2^3x/2^y
using exponent rules you get 2^(3x-y)
3x-y is given as 12
so the answer is 2^12
!nosols
As a helper, please do not give out answers that could be copied as a homework solution. Have the student work through the problem themselves and guide them along the way.
looks like an sat question
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turns out it was one of the hardest sat questions
i just wanted to find math 💀
i just wanted to find math 💀
and understand it
to fill my hollow brain
hardest?????
mf
thats like
the easiest question
on the entire sat
i didnt send an invite
change ur password my man
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Hi! I'm actually so confused and I have no idea where to start. Picture was taken from a practice test done a few hours ago!
log(100000)?
remember when base is hidden, it normally means base 10
10^4?
4?
yipee
my horses are held because i think its e
instead of 10?
i missed like 3 lectures cause i got super sick
😭 i guess the first term? i dont know why the log is exponited
i did not
we arent allowed one
math department said nope
oh yes sorry
im exhausted i apologize
log_a(x) is the opposite of exponentiation a^x
[\log_a(a^x) = a^{\log_a(x)} = x]
Invariance
That's the entire point of log
ohh
All the other log formulae come from that one
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how to show that (x,y) is perpendicular to (-y,x)
these are vectors btw
Oh
i was just abt to say points can't be perpendicular
Dot profuct = 0
Dot product -xy+xy=0
Sorry Imma echo
That's why I was getting that confirmed at the start lol
oh ok\
also how to show that |u cross w| is the area of a paralleogram with sides |u| and |w|
like i gotta prove it
That for cross
i meant to put magnitude
This make sense?
Yellow one is u
Purple one is w
Red is |w| sin theta
Rectangle ABCD has the same area as the original parallelogram
Which is |u||w|sin theta
Which is exactly what the cross product is
This make sense? @velvet cove
hold on i didn’t see it
how you get this
oh wait nvm
ohhh
i thought u had to use that one A=1/2 ab sin(c) formula
ty
Ur welcome
.close
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yes
Please only use the <@&286206848099549185> ping once if your question has not been answered for 15 minutes. Please do not ping or DM individual users about your question.
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!show
Show your work, and if possible, explain where you are stuck.
Haven’t looked too closely but i’m guessing maybe you didn’t account for the pasture sharing a fenced wall?
the perimeter isn’t 2x + 2y
there’s the fence part in the middle that divides the pastures
draw a diagram for these problems
it makes it much easier
@fallen fulcrum
bruh
you asked for help then disappeared
😟
T_T
draw it
it’ll make more sense
two pastures
separated from each other
just draw it please
send it
perfect, now the line in the middle will have a length of what
yea P = 2x + 3y
well, maybe we should label it better
because the larger pasture isn’t x by y
x is the length of the length of the larger pasture + length of smaller pasture
in your diagram
how about you label just the length of the larger one x
and the length of the smaller one idk w or something
you choose
then the perimeter will be 2(x+w) + 3y
@fallen fulcrum do you follow?
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what
did you not get it?
oh don’t feel embarrassed though
you don’t have to leave just because you can’t figure it out
but you can try again tomorrow ig
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Help
Can you guys help to double check
3^6 is not 216
your work looks okay except for (4)
looks good apart from 4
handwriting?
It's 5
ah
looks like a 6
Im rushingg
Is the part one good?
I mean A.
@languid ridge Has your question been resolved?
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hello I need help...
@grave anvil Has your question been resolved?
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need help with these I aint getting the correct answer I have done it but I guess it is wrong
what happens when you subtract row 2 from row 3?
pinging just in case
maybe you want to show your work to see why it's wrong before doing this?
Oh our teachers here taught us a different method that you might also know
theres a method to calculate a 3x3 determinant,where we take the minor of all the elements in first row
something like this
yes development into minors
yep I am trying this method
the end result I got simplifying this equation is
I just wanted to make sure if it seems correct to you
and Can you also if you have time,explain this method to me too
so
do you remember that adding/subtracting a row a certain amount of times to another row doesn't change the determinant?
oh I have to take commons i guess then It can be simplified more
for example
oh yep
if you replaced row 3 by (row 3) - 56(row 2)
the determinant is unchanged
or row 1 replaced by (row 1) + pi * (row 2)
I see
ok
okay I got it
so what happens when you replace row 3
by row 3 - row 2
that means I have to substract like (a+c a+b a) - (a+c a+b a) then the answer will be the third row right?
you mean (a+c a+b a) - (a+c a+b b)
right?
and yeah you replace row 3 by the result
oh yeah misplaced a again
oh okay
oh btw we substract the corresponding element with each other like (a+c) - (a+c) or something else
@hearty nova Has your question been resolved?
why would there be something wrong with this method
yeah
that's how you add/subtract rows together
entry by entry
oh there is nothing wrong
okay btw have you tried expand the answer you got I tried it I guess i got something wrong
(a-b)(b-c)(2a+b+c) = (a-b)(2ab-2ac+b^2-c^2) = 2a^2b - 2a^2c + 2abc -ab^2-b^3-ac^2+bc^2
mmh wait
the abc coefficient should also be 2abc
oh yeah there's some phantom coefficient that appeared
I get the same thing as you
@hearty nova Has your question been resolved?
Phantom coefficient?
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Did I do 16 correct
@heavy palm Has your question been resolved?
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(x - in_min) * (out_max - out_min) / (in_max - in_min) + out_min
this is the formula for mapping a number in a range into other number range
i don't understand why we divide it with this (in_max - in_min)
+out_min is offset i guess
x/(in_max-in_min) would be percentage between inputs if we multiply it
with (out_max-out_min)
and offsetting it with out_min would be the same?
oh i got it nvm
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X = pi
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f(t) is given graphically
$$F(x) = \int_4^x f(t) dt\ $$
bonk
bonk
the evaluations at a particular x of the anti derivative
You have f(t)
a graph of it, yes
Can you send a pic of the question
i guess you can only estimate
Ok yes, so plug in the value from F(x) into your integral and compute
No you can get definite answers
treat them as straight lines
It doesn’t matter
the best you can do is estimate
Integrals don’t require the lines to be curved
Just stop talking please
You can use triangles to figure out the area under/above the curve
0 to 4 is a triangle with base 4 and height 7 for example
so for F(0) im integrating "f(t)" with bounds 0 and 4
And it’s below the curve so it’ll be negative (which can also be seen by switching the bounds and giving it a negative)
charlie... you literally assume that the blue thing is a straight line in the process
4 as the lower and 0 as the upper
the question is trivial
The area below the x-axis is negative, but the bounds are inverted (4 to 0 instead of 0 to 4) so it will invert the sign again, giving a positive overall result
so when im at F(10) am i subracting the part between 8 and 10?
At F(10) you’re finding the integral from 4 to 10
Which will be the whole triangle above the x axis, and a negative little triangle from 8 to 10
It’ll help you visualize if you draw lines in your head with the bounds at a particular x value to see the resulting triangle
F(8) is 12 and the little triangle is looks to be of area 2.
Yes so subtract 2 from the integral from 4 to 8
its not accepting 10.. maybe im reading the lines wrong
it could be 2.5 x 2
making a = 2.5
What’s the area of the triangle in the middle
the large triangle in the middle F(8) = 12
so stupid.. that little triangle is base =2 and height = 2.5
You can see it by looking, I didn’t notice myself
You can also infer it from the area of the whole triangle @still berry
Look at the area of the triangle on the right and see where it gets split
It’ll be a ratio of the total area
this one?
Yes
intervals were simple enough so i got this question knocked down. I have another one to do so ill see if that goes smoothly.
thanks for your help!
No problem at all
.close
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could anybody solve this?
I tried but didn't succeed
Show your work, and if possible, explain where you are stuck.
@cunning galleon Has your question been resolved?
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try taking
how to find the recursive rule for the sequence 1,1,1/3,1/4,1/15
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.reopen
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Why doesn't the rocket have an initial speed?
context?
I know it's a stupid question, but I want proof
When does the body have an initial speed and when not?
When the problem specifies that it does.
Or if you're in a practical situation, when the practical situation says it does.
Rockets can absolutely have an initial velocity, if your problem is regarding, for instance, the calculation of a burn for a transfer orbit.
on the other hand we would expect it to be stationary if we started at the launch pad. so very context dependent
So you say that if the rocket is in static surface and then launches, it does not have an initial speed, but if it starts from a moving surface, here the surface has given it an initial speed because it is moving?
Is the same with cars and all objects
yeah, or more generally just, if it's... moving, at the start
where what counts as the "start" is kind of just dependent on where you start calculating from
if you happen to know that the rocket launched from a static surface ten seconds ago, but what you have are numbers for what it's doing now and you want to predict the rest of its trajectory from that, then it would have an initial velocity, because it's moving
Do you mean, according to the pedal, determine the initial speed, for example, we study the movement of a rocket from t=7, then t=12, where the moment t=7 is the first moment here, the rocket has an initial speed
@fading marsh Has your question been resolved?
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Is there a way of constructing a surjective ring homomorphism from R to Q? I saw on Stack Exchange that if you treat R as a Q-vector space, you can sort of construct a surjective group homomorphism by taking a basis for R and sending everything except the multiples of one basis vector to 0 (I say sort of, because this requires axiom of choice apparently). Is there a similar thing we can do for a surjective ring homomorphism from R to Q?
I guess what I'm asking is, can we vaguely know what a surjective ring homomorphism from R to Q looks like? Because, in the group case, while we do use choice, you can get an idea what the map is actually doing.
Oh wait, I guess I should've asked first whether such a thing even exists, because I assumed that between a ring and a subring, a surjection always exists, but that might be wrong.
@ruby crest Has your question been resolved?
say such a homomorphism phi exists. It needs to satisfy phi(1) = 1 and then phi(2)=phi(1+1)=phi(1)+phi(1)=2. Now consider phi(sqrt(2) * sqrt(2))
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another way, using a bit more ring/field theory, there is a theorem that states that any field homomorphism is always injective, so phi would have to be bijective
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May I get help?
well, it gives you B "82 take only cream"
a and e?
374 coffee drinkers, only 65 do not add sugar or cream
374-65=309
309 use at least one of the addatives
so e is 309
and a is 309-64-82=163
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- The trolley can carry 293 kg safely.
- Each block has a mass of 10 kg.
Hence,
$\text{Maximum Number of Blocks} = \frac{293 , \text{kg}}{10 , \text{kg/block}} = 29.3$
DW1
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how can i fix this
download more ram 
anyway, probably not a math question
more wam*
dedotated wam
@velvet cove Has your question been resolved?
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every subset $A_i$ is contained in $A$
rain
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- Suppose there are two urns. Urn 1 contains 100 chips: 30 are labelled 1, 40 are labelled
2 and 30 are labelled 3. Urn 2 contains 100 chips: 20 are labelled 1, 50 are labelled 2,
and 30 are labelled 3. A coin is tossed and if a head is observed, then a chip is randomly
drawn from urn 1, otherwise a chip is randomly drawn from urn 2. The value Y on the
chip is recorded. If an occurrence on a head on the coin is denoted by X = 1, a tail by
X = 0, and X ∼ Bernoulli(3/4). Compute the following:
(a) E(Y | X = 0), E(Y | X = 1), E(Y | X)
(b) Check that E(E(Y | X)) = E(Y )
(c) E(X | Y = 1), E(X | Y = 2), E(X | Y = 3), E(X | Y )
(d) Check that E(E(X | Y )) = E(X)
I've found E(Y|X=0) and E(Y|X=1), how do i find E(Y|X)
dawg
I accidentally typed enter too early mb
E(Y|X) is not a number, its a function of X
I'm aware of that
so the function has to return what you got for X = 0 and 1
Yeah but how am I supposed to show as summation to find it? Like it's intuitively 2.1 - 0.1x (E[Y|X=0] is 2.1 and E[Y|X=1] is 1)
But I'm not sure how to sure the work of how I got there
I just kinda saw it
I'm sorry if I'm coming off as rude
Not at all my intention
so E(y | x. = 0) is expected value of y when tails
so from urn 2
is $0.2*1 + 0.5 * 2 + 0.3 * 3=2.1$
i think?
oops
reaver
using expected value we weight each by their probability of occuring
That is correct
isnt that it?
I'm struggling to find E[Y|X] in general terms
As in a function of X that describes it
oh
Well, I have it
I just don't know how I got there
It's whatever, I think I got it
Thank you
wouldnt you just weight each one or am i tweaking
well
That is the law of total expectation
isnt that right or am i tweakingnginginggngn
The proposition in probability theory known as the law of total expectation, the law of iterated expectations (LIE), Adam's law, the tower rule, and the smoothing theorem, among other names, states that if
X
{\displaystyle X}
is a random variable whose expected value
E
...
or is that just E(Y) then?
Yeah that's E[Y] not E[Y|X]
reaver
Can I ask what part specifically you are trying to solve?
E(Y|X)
been watching for a while, what topic is this
Probability theory and statistics
Well E(Y|X) is a random variable. It doesn’t have a determined value
I am aware of that
I know it's 2.1 - 0.1X just from looking
I just don't know how to show my work for that
I know that E[Y|X=0] is 2.1 and E[Y|X=1] is 2
i think it should be 2 maybe?
It's not a numerical value
I see, one way to state the equivalency would be to show that the pmf of E(Y|X) and 2.1-.1X are the same
In this case that would be computing the outcome table for both
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could someone please help me on how to do this
what i did was squaring the bottom equation
then subtracting
3y^2-4xy=9-k^2
is there someone significant about the difference of squares?
think geometrically
this means you want the line to be tangent to the circle
can you use calculus?
alright then the simplest solution is this
???
take the second eqn, solve for x
make it a quadratic
idk
then set the discriminant equal to 0
what would you have suggested?
x = 2y + 3
(2y+3)^2 + y^2 = k^2
substitute either x or y in terms of the other into the first equation
expand
Sup knief 👋
oh okay
what are you up to
the line is tangent to the circle
?
im guessing thats what he meant
yes that’s what he said
What’s the problem
find the derivative of the first equation at a point in the second equation?
@tropic brook did you understand what we proposed
yeah i did
what town hall are you
sorry idk why i didnt realize i coulve just substituted earlier
uh 14 i think
alright thanks y'all
is this right
you’re welcome
oop alr
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△ABC is an equilateral triangle. D is a point on AC, and E is a point on BD. Let P
and Q be the circumcenters of △ABD and △AED, respectively. Prove that △EPQ is an
equilateral triangle if and only if AB ⊥ CE
can anyone please help me solve this problem
prove the statement
i tried but my teacher said its incorrect
Could you draw an accurate figure
and send it
@sick wave Has your question been resolved?
i tried but the figure is so confusing 😭
@sick wave Has your question been resolved?
this question is from the ongoing usamts competition, which you aren't allowed help on
<@&268886789983436800>
do you have a link?
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(we just like to double-check that the competition is indeed ongoing, since sometimes users erroneously report sample problems as the actual competition)
(but in this case the report was correct)
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When doing Sum and Differences and I reach the part where i must convert the sin and cos into the coordinates of points of the unit circle which one do I pick for which one. X or Y?
y is sin
x is cos
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can someone explain this solution to me
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anyone know how i can write this as a general solution of a linear combination
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Hey guys, can anyone explain to me how to calculate the pullback?
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Right so I don't fully understand this question
I am tempted to understand "closed subspace" here as closure under addition/scalar multiplication
But this exercise is in the context of a chapter about continuity of functions from one metric space to another
So is this asking me to show closure in the topological sense? Is that equivalent to closure under addition/scalar multiplication?
is this theorem relevant?
yeah topologically closed
more general theorem: all finite dimensional subspaces are closed
yeah thats the next part
good to know, any hint as to how I can approach this?
Orthogonal projections
you can use the probably known fact that linear maps are continuous (in finite dim, otherwise bounded linear maps)
I think could do it
Oh yes, thats better
.close
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err how to solve
best bet when you see a sqare root is to square everything
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I don’t understand how the teacher did this
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I need a lot of help in this 
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hi im learning about proofs
i'm currently working on a proof and i want to use pigeonhole principle to supplement my proof
my problem is, pigeonhole principle is typically stated as follows:
if n items are put into m containers, with n > m, then at least one container must contain more than one item
but in my case, i want to show that if n items are put into m containers, with m > n, and strictly 1 item per container, then at least one container must be empty
is this still pigeonhole principle? and is it applicable in my case?
Pigeonhole is great only for finite element proof
Depending what you want to proof though
You still have to do an induction like argument
n and m are finite?
And argue at one point that you have some empty container
Yes
Classic pigeon is for finite
yea
so i cant apply pigeonhole here?
For your specific problem you have to create an inductive step that you argue you have m-n empty container
You can
Your prob is classic
ok i dont know mathematical induction yet
yea pigeonhole principle
I feel like induction is more basic..
Because if you want to prove your proposed question
You have to induct on n
can you show that my question is true using only pigeonhole?
or u have 2 use induction
It’s definitely true
Because of pigeonhole principle
But I can’t prove it without induction like proof and truth is kinda different
Proof is formalism
Maybe there are other ways I don’t know
so i can just say something like "by pigeonhole principle, at least one container must be empty" ?
without showing induction
Yes you can, just don’t do it in exam though
Because you don’t have an argument that there’s an empty container
Even its obvious
I don't think you need induction
If you learned stuffs about bijections over finite sets, you can use this
If he knows then he would defo know induction
ye
If A and B are finite and there exists a bijection between A and B, then |A| = |B|
This result is sufficient to prove what you are asking
It’s actually rigorous to just write by induction it’s clearly that at least m-n container are empty
It’s actually rigorous
By induction it’s clearly
Depending the context
Using the word clearly twice won't convince me here! What is your proof by induction?
Omitted… I am just joking
My professors do that all the times 🫠
i'll just put the statement to prove here again:
if n items are put into m containers, with m > n, and strictly 1 item per container, then at least one container must be empty
tbh i just want to apply pigeonhole principle so bad, because it literally sounds like pigeonhole principle
Bijection between which sets?
Can’t do it 🫠😭brain fog
idk bijection, i jus dont wanna go too abstract u feel me
If you want a rigorous proof, this is a particular case of the following result:
If A and B are finite and there exists a bijection between A and B, then |A| = |B|
Now, if you absolutely want to apply the pigeonhole principle, you can apply it the reverse way: You can associate containers with the items
Since there are more containers, it means at least one item has been associated with two or more containers
You can deduct from this that at least one container will be empty
I edited the more general result, that was badly written, sorry 🙃
@tulip jewel Has your question been resolved?
i tried proof by contradiction:
suppose that all containers contain strictly 1 or more items,
that means there's a total of w items
where w >= m
but we know that m > n
so there can't be 1 or more item per container
in other words, some containers contain 0 items (as there can't be negative items)
is this correct
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hello i need help with a math problem
wait i'm not sure what the command is
,rotate 270
basically
we are supposed to show that 2 < (a^2+b^2) / 16 < 5
ik the left part but i got stuck on the right part
.close
Closed by @manic axle
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but u did it right
.reopen
✅
last step was that 2<9/4 + 4/4 = 13/4 = 3 1/4
i struggle to read that
9/4 + 1/4
yeah
ohhhh
so 2< (a^2+b^2)/16 < 5
welcome
i legit thought u got banned when u deleted ur texts XD
well i guess imma close
yeah cya
.close
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Wrong
why
hm?
10/4 is 2.5
which is greater than 2
Yes and that’s a problem
yet smaller than (a^2 + b^2)/16
yeah
did u know that if u hold spacebar u can draw with the mouse by moving it with arrow keys
anyways thats off topic
i knew
oh cool
Oh I’m stupid lmao
its okey man
Read it off
i made stupider mistakes
Wrong
like 3+2 = 6
yeah 3+2 is so similar to 3*2
i dont wanna get banned for spam closing can someone close it please
its already closed
isee
lets just leave the channel
well good bye
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am i on the right track here?
stats practice question, have a final coming up so really want to understand this
im not quite sure if im finding these values correctly, so would appreciate help please
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Alright so I'm trying to understand how linear regression works but its kinda hard for me to understand
Basically I understand using the center of the data to start out with
so basically we caluculate the x and y mean
Once we do that,
We find the slope using this point and each point in the data sest
@proper cosmos Has your question been resolved?
and then
for some reason subtract the x and y mean off each point and multiply the x and y answers together then divide by the variance of x
but i dont understnad why
<@&286206848099549185>
hello!
hii
i need help too
O
ig imma write something for anyone who sees it
Ok so basically to solve for line of best fit in linear regression
You take the mean and center the data around the mean
because the mean will be in the line of best fit
so we find the mean x and mean y of all data points
then we center the data around the mean by subtracting it by the mean
so we can represent that as
$x_i - m(x)$
Sinister
x_i representing the point and m(x) represent the mean that we found
we also do this with the y values aswell
$y_i - m(y)$
Sinister
My question is
Why do we multiply the result we get for each points x and y and sum them up
and then put that over the sum of $(x_i - m(x))^2$
Sinister
so the equation ends up looking like
$slope = sum (x_i - m(x))(y_i - m(y))/ sum (x_i-m(x)^2$
Sinister
First why do we multiply the centered points y and x together and also why do we square the bottom expression
Why isnt it just sum y centered / sum x centered
<@&286206848099549185>
<@&286206848099549185>
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I don't know if anyone can exactly help with this but currently I have solved a system of equations, found the respective solutions, and plugged them back into my equation to get the equation in the first image. I know it is correct up until this point as it has been double triple checked. but now, I need to go from this, to the solution in the second image, but I keep getting completely stuck. I have tried writing the e^theta terms as cosh(theta)+sinh(theta), and then using sum to product identities on them (as I was pointed to do) but I keep getting a completely different solution than the one in the second image
so you want to go from the first image to the second?
yes exactly
what is $\omega$
rain
sorry their omega is my theta
and I have been able to get to similar to that, with the correct angles in cosh and sinh, but with my terms i keep getting like, cosh(theta/2)(something)+sinh(theta/2)(something) so I cant exactly factor out the cosh(theta/2) like they did, etc
thank you!
is the $\frac{2n-3}{2}$ inside the sin and cos or no
rain
yes it should be, LaTeX error
oki
We're back with another one 
yeah I've been here a good few times with the overall problem 😭
Awwww
it does look like it's one of those painful ones again 
I have a notebook full of schizophrenic looking scribbles and 2 weeks worth of headaches ahha
as have I! hence I am majorly lost 😭
that is so real
tysm!
i will let u know if i get anything normal
im off my meds so
idk if it will work
🙂
"normal" 🤣
Putting e^θ=coshθ+sinhθ I get the following
But then its applying the sum to product on these that I absolutely do not get the “correct” final solution
So I fear I went very wrong at that step^
im still tryin
me too😭
HOWWW
lemme try to explain
ur a genius omg
🙂
in your second image, I am going to ignore the factor of $\frac{-2i^n}{\sinh(\omega)}$
rain
so that means your first image will be
$X_n = \frac{(1+i)i}{2i \sinh(\theta)} \cdot [e^{n\theta}(-e^{-2\theta} - ie^{-\theta}) + e^{-n\theta}(ie^\theta + e^{2\theta}]$
rain
then
$X_n = \frac{-2i^n}{\sinh(\theta)} \cdot \frac{i-1}{4} \cdot [e^{n\theta}(-e^{-2\theta} - ie^{-\theta}) + e^{-n\theta}(ie^\theta + e^{2\theta}]$
rain
so ignore that first fraction b/c i don't wanna deal with it
and then u can put it back later
then
$\frac{1}{4} \cdot (i-1) \cdot [e^{n\theta}(-e^{-2\theta} - ie^{-\theta}) + e^{-n\theta}(ie^\theta + e^{2\theta})]$
rain
the easiest way is to
multiply this out
then you get something that looks like
$\sinh( \theta(n-1)) + \sinh(\theta(n-2)) + i[\sinh(\theta(2-n)) + \sinh(\theta(n-1))]$
rain
maybe i missed a constant 1/4 idk
and then
you use the identity
$\sinh(x)-\sinh(y) = 2 \cosh\left(\frac{x+y}{2}\right) \sinh\left(\frac{x-y}{2}\right)$
rain
ofc, you can group terms to get the $\cosh() \sinh()$ term before converting to this, but what i said is just the way i did it
rain
its more annoying to factor than to jsut use an identity
make sure to keep track of teh 1/4
should disappear by thee nd
🙂
sorry I'm at work while doing all of this I'm gonna look at this in a moment but omg you cooked on this
ty girlie
yeah I shouldve just worked with it in the e^theta form rather than keep putting into the huge mess with the hyperbolic trig right away and I think it would've fallen out clearer
ya
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5 ³√64+³√14-6
That cant be possible Right
It can be
14 cant be simplified
Looks like it’s written wrong
or it really doesn’t simplify
Try writing it based on what you think i wrote
yes so not possible
unless they want you to write 14+ cubed root of 14
What do i write then?
do you have a calc
Yeah
as in are you allowed one
No
then this I guess
Wdym
yeah it's just $14 + \sqrt[3]{14}$
bee [it/its]
@zinc topaz Has your question been resolved?
why would it be that
Wut
the cube root of 14 = 2.41014226 etc
its still a number like any else
so you can add to other numbers
the 14 there is from 5 (³√64) - 6 btw
what about it?
it won't be a single term but yea, it's possible to simplify it
it'd be something like a√2 + b√3
So copying it?
wym copying it?
Your essentially just gonna copy it if not possible?
not sure what you mean by copying it
you can simplify your expression until you get to that form
Alright
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if CH is in the same place, you only need to find how many ways you can arrange AIR
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Hey folks
So for those who have been helping me for the past few weeks I passed my second linear alg exam
so thanks for that
now i just need to make up for the failed first exam
which somehow i tend to have more trouble with
1a:
Let A,B in R3X3 with det(3A) = 216 and B, with alpha in R
Find for which values of alpha the following is correct:
$det(A^{-1}(B+I))=-5$
Multiply both sides by A
Ull get
(B+I) = -5A
Take det on both sides
@open sage
Oo