#help-33
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"sum check"?
$\overrightarrow{AB} + \overrightarrow{BC} = \overrightarrow{AC}$ is \textbf{always} true. so checking that won't tell you anything.
Ann
you will want to take two of these three vectors (any two) and check whether they are parallel.
We will check if they have any scaler quantity in common
AB = x Bc
Like this
Bc= x CA
yes
B is indeterminable
it may be true or it may be false, but we do not know
we cannot say either way
False how
well it can so happen that a = 2b
then a won't be b and won't be -b
so (B) will end up false
(for the sake of my example i am assuming here that a and b are both nonzero)
If a =2b then it's clearly collinear no?
yes
that's my point
the premise (a and b are collinear) is true, but statement B (a = ±b) is false
you ask how B can be false i give you example where B is false
simple things
but B is false.
a=2b is not false
and it isn't supposed to be!
IF a and b are two collinear vectors,
this means we are ONLY considering pairs of vectors that ARE collinear
and we DON'T CARE when the vectors AREN'T collinear
yes
i've known you enough not to ascribe malice to this but please see the clear logic here
but B isnt false because a and b are collinear if and only if $ \exists \lambda \in \mathbb{R}$ s.t. $a=\lambda b$
calculus is fun
you are sowing more confusion
suppose we took lemda = 1
let me repeat my original point
then b is correct
WE CANNOT CONCLUDE EITHER WAY whether B is true or false with ONLY the premise that a and b are collinear.
we can say it is correct
which is clearly not collineary?
because i think you are failing to see my logic
I think yes
ok
so let's first agree on some premises:
- every human on earth is either married (to someone, but that's not important) or not married.
- children cannot be married, but adults can.
do you agree or disagree with these premises? @tender mantle
ah yes i see your point
we can say that it is wrong
because what this statement says is that $\vec{a}$ and $\vec{b}$ are collinear $\implies \vec{a}=\pm{\vec{b}}$ $\forall \vec{a} \vec{b}$ which satisfy this
calculus is fun
and this is wrong because you can find infinitely many counter examples one of them is the one you gave
agree
but how?
ok then in this case
let's say there is a room with some people in it
okay yes
if we choose a person in the room and they turn out to be an adult man, then the statement "the chosen adult man is married" is?
(A) definitely true
(B) indeterminable
(C) definitely false
A
if we choose a person in the room and we find out that they are an adult man, then the statement "the chosen adult man is married" is?
(A) definitely true
(B) indeterminable
(C) definitely false
answer again
A
So you meant in the statement that adults can be married cannot be married?
But if we choose and find out it is children then it is definitely not married right?
don't care
Then we can say a definitely statement
not what i asked
back to our question
instead of people we now have pairs of vectors a and b
instead of adults we have pairs where a and b are collinear
instead of married people we have pairs where a = ±b
Hmm so?
Ahhhh
I am sorry i still didn't get it with your example. I meant I couldn't connect it
@undone bane can you help me in Hindi?
a= +-(b) is clearly visible that it is co linear
How can we not determinate it?
My answer to the question is C
They should be proportional
The rest of all are correct to me.
What is your answer to the question Ann B and C?
I think you can say that only option A is absolutely true statement here. That immediately makes option C incorrect. Option B and D can be true in some cases, but not generally true.
I'm assuming lambda in A is nonzero here
Option B and D can be true in some cases, but not generally true.
i tried saying this for the last hour or so, but language hard.
sorry, vectors nahi pda hai abhi
What is your answer to this question generally or not generally?
If a and b are co linear and non zero then a b d co linear 1000000%
I would like to know how they will fail to be co linear option B and D
I'm not saying they're not collinear. I'm saying that collinearity doesn't imply anything about their magnitude
Option B implies they have the same magnitude, which is not necessarily true
Co linearity just means parallel
Yes
No direction and magnitude affect it
They can be same or not same in direction and magnitude
Key words "can be"
Option B is saying that they necessarily have the same magnitude
What? They are vectors not megnitude
Ohh wait
I'm not sure if this is language barrier or not (I hope it is) but all I can say is that options B and D are making unnecessary assumptions about the magnitude of the vectors
But they are satisfying the statement so we can't be discarded
They satisfy the statement in some cases
Not always
A is ALWAYS true, provided lambda is nonzero
C is ALWAYS false since A is true
In that particular case it is always true
but the question never said that vectors a and b are those particular ones, didn't it
What is your example like this to be fails
This is a problem with the generality of the statement
I'm not saying it's not true in certain cases
I'm saying it's not ALWAYS true
I just want to know one single example to feel it can be wrong too
In fact, you can choose b = 2a
Can you make it one example no??
b=2a is collinear with a
but $\vec{a}$ \neq \pm\vec{b}$
wait how do you do parallel again
TooManyCooks
Compile Error! Click the
reaction for more information.
(You may edit your message to recompile.)
The plus minus guarantees they have the same magnitude
You meant that if a and b are co linear so we will have many vectors in a=lembda forms
But some of them will be a=b
Hahaha it do be like that
Now i can understand what was she saying
It is true only for a=b
Not for all a,b pairs
Okay now option D
by saying that a and b have the same direction
they don't have to have the same direction to be collinear
They are just picking some random vectors which is satisfying
Set X : A,B are collinear
Set y: same direction and different megnitude
Y is subset of X so how can we it is false
they're talking about subsets of X
Subset will be always true
We are only talking about Y only ...there always be a case for each subset to make it false in some terms
Is this why you guys were saying either or either not?
The only premise they gave is that a and b are collinear
D is immediately saying they have the same direction, which need not be the case
Then we are just comparing X and Y subsets
If this is the case then the full definition case option A will be correct
B,C,D all are incorrect
C is totally incorrect
B,D will be incorrect in some cases
Say YES for my statement @stoic saddle @ancient slate
i don't want to continue this sorry
For nonzero lambda, only A is true always
C is always incorrect, B and D are sometimes correct, sometimes incorrect
No problem
That's it
Thank you all of you
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What do you think is the answer?
|lembda| |a|=1
lambda*
yes but this isn't one of the options above as currently written
see if you can rearrange it to be so
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does $\frac{-y}{2} \lim _{\varepsilon \to 0} \qty( \varepsilon ^{\alpha + 1} ) = 1$ imply necessarily $\alpha = -1$
jan Niku
I know this is probably a dumb question
y is fixed?
yea
also long time no see jan Niku 
Was Neko
before the dark ages happened
you're doing your masters now?
1 year
you gonna do grad?
yea
im @ nyu rn for undergrad
theres no way in hell im doing a ms here
cause my scholarship wouldn't carry over
also yea 
i do need to pomo cause i stay at home to study a lot now
is there some study server were both in
possiblly for a bit? pomodoro server or something
was mostly on here before they removed the voice channels
what is happening here?
sup arjunn

inf arjunn
I can try it
what's the point of -y/2
how about just the study server
I would say it both implies the value of alpha and y 
yea sure
youre on it?
I think 
i usually go to 6
not anymore
ah
you could link me later
okay
y doesnt have a value
its a variable
but for sure theres no other way for this to happen right
alpha has to be -1
I don't think it has to be -1
yea im confused
but i guess the goal is only to find a candidate
@ancient slate it comes from a perturbation problem
the thought was to assume that $\epsilon ^{2 \alpha + 1} y^2 \sim -2 \epsilon ^\alpha y$
jan Niku
the limit results from this
im not really certain if the process is supposed to determine alpha, or just candidate alpha
or if multiple values of alpha can even come from this
this specific limit i mean
but if you assume its fixed then it must come out as -1?
tfw wrong epsilon 
varepsilon or riot
either way
Is there more context about that expression that you can provide?
Well, the limit only exists for $\alpha \in \mathbb{N}_{0} \cup {-1}$, right? And it's 1 iff $\alpha = -1$ and 0 otherwise? Or am I missing something \thonk
it comes from trying to find roots of $\epsilon x^2 -2x+1=0$
jan Niku
ye

im not sure how the rest of the solutions are getting tossed
mm... yes... dominant balance.. mhmm
clearly epsilon = 0 is trash
lol idk i just "learned" this today
i guess you just assume that one of the terms is asymptotically not important
I have no idea what it is either 💀
along epsilon
I guess this implies that the other two terms are asymptotically equivalent
so if you have A + B + C = 0 and C vanishes
then A ~ B
i guess ONLY C vanishes is maybe more correct
And then y is forces to be -2, no?
y is a variable
oh, i see what you mean

yea this whole process doesnt make any sense to me
yes
Tell me if I get this right
$\varepsilon^{2\alpha +1} y^2 - 2 \varepsilon^\alpha y + 1 = 0$
TooManyCooks
Then you said take limit as epsilon goes to 0
which means the leading perturbative term is $-2\varepsilon^\alpha y$
TooManyCooks
did I get that right?
well, no
the thought is that you assume that one of the terms is insignificant
so then the other two will be significant
then they should be asymptotically equivalent
one wont dominate the other
so i dont think this makes sense
its more like we assume that a term will vanish, and then check them one by one, to see if the assumption makes sense
i just happen to know that the term 1 will vanish asymptotically
if you're solving for this, can't you try like ex^2-2x\approx 0
for dominant balance
well, if you check the other two, you'll see they fail
so if one works, it will be 1 vanishing
ultimately this is basically what happens
i think?
the substitution with alpha results in $y^2 - 2y + \epsilon = 0$
jan Niku

why sad?
i did not nearly pay enough attention in my numerics class

@ancient slate the balance is gonna imply asymptotic equivalence right
or am i crazy in jumping to this
my prof just sorta skirted over everything
it makes sense that in A+B+C=0 if only C vanishes then A~B must be true right
otherwise either A or B would vanish, too
I got promoted 
heyy welcome to helpful
ohhh
@warped wind i get what you meant now
about -1
but then this also has implications for the value of y
so thats a problem
maybe
Yes
yea im not sure how to resolve that
Unless something monkey funky happens for the whole expression for the cases where the limit is going to infinity
my prof just matched powers
But I would assume not
but this seems dumb to me
ill ask him about the ~
i must be making some mistake in moving from the assumption into ~
i dont see how anything else pops out
thanks for the help, crew 
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how can i show that:
Oh shit sorry didn't notice you had already posted here
$1-cos(x \pi) =2sin^2(\frac{\pi x}{2})$
Use the fact that $\cos(2x)=\cos²(x)-\sin²(x)=1-2\sin²(x)$
calculus is fun
@gray shale Has your question been resolved?
ye but it's 2x not pi*x
$\cos(2K)=cos^2(K)-sin^2(K)=1-2sin^2(K)$
let's see if renaming the variables here help you
LordFelix
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So I set up the integral but I feel like the smaller radius might be wrong
how about this, someone correct my reasonining. I don't care what the integral is rn.
I chose 27x^3 as the larger raidus because it was the furthers way from x= 2
and x = 1 to be the smaller radius because it was closer to x=2
look at it geometrically, is the inner radius changing at all?
ummm
hmm
Is the inner radius changing
no?
hmm wait
you've stumped me. Cause I wanted to say that I don't think the radius would change but then how do I explain the larger radius
that will change depending on x
its been a minute since ive done this let me look at my old notes
okay
okay so this should be shell method, with respect to x ( same axis of rotation ) if memory serves.
to help this is the washer/disk method
you are using washer method, which would be a y integration i believe
I was told you can use them both
I thought dx because the width was determined by the x axis
in this case, x axis radius, not width.
width of the washer would be dy
draw it out
its a horizontal washer
horizontal washer meaning like it's laying flat
right
instead of say, on it's side
right, but i would 100% use shell method here
if you've already covered that, that is.
Sure
shell method allows you to use the same axis of rotation if rearranging the function in terms of the other var gives you something ugly.
so that's 2pi times height times radius
I feel like that's going over my head
idk why
when we talk about axis of rotation I start to gloss over
good rule of thumb is disc/washer method uses the other axis that didn't rotate.
don't stress, there's only two ways to rotate, by x or by y.
in this case, its rotated "around" an x value, so we use the other axis for disc/washer, since we integrate by width.
the other axis being the y axis?
yes
if we rotated around a y value, then x would be used, since our width would be in the x axis.
dx/dy is shorthand way of saying how we slice things
you wouldn't slice the volume with dx here, because you'd be cutting straight through the volume, instead of getting only a uniform slice.
with shell method it allows us to use the same axis and makes it way easier to deal with something like this when the washer method will give us an ugly cube root.
what do you mean use the same axis
axis of rotation
with washer/disc you are forced to use the axis that didn't rotate.
shell i think can be either/or
ughh
yes
It's just I'm not getting some of this stuff. I have the main idea, computing the volume using integration. Boom, got that down.
But some of these smaller details I'm lost
yeah
the key is drawing it out
it helps a ton
and remembering that when we slice, we must get the shape we need. otherwise its the wrong axis.
so if you draw out the cylinder we will integrate
i marked the inner and outer radii
I see that
so when x = 1, we need the radius of 1 from x = 2
but
if we take x at 0.5
radius will need to be 1.5
what's the relationship of those points?
if we just rotated at x = 0
we could just use 2pi x * height
but since we are rotating at a specific x, we need to modify that x
2pi ( circumference ) * height
what formula would give us the proper radius at every x from x = 2
sorry my book says circumference for the formula, but technically we are replacing that with the distance from the point of rotation
it's fine I recognize that from my own reading
I don't know
but now I think the height would be y = 27x^3
hold up we aren't at height yet
but yeah that would be the height
lets say i give you x = 0.5
whats the formula for finding the distance from x = 2, to that 0.5
its very simple, dont overthink it
just look at the graph and tell me the distance from 2 to 0.5
would you just take the difference between 2 and 0.5 ?
right
0.5 was the x we chose
BUT
that relation will hold for ALL x on the axis
ohhhhhhh
so we get (2 - x) for our radius of the shell
so 2 - x would work for every x
right
ahhhh
so thats our circumference for the formula
I see
so then put it all together and integrate
that will be a key concept moving forward
you'll need to be able to visualize distances along the axis for later stuff like hydrostatic pressure
calc 2 is fun because it has so much variety, but also terrible because of it haha
variety with what? Applications?
just so many new things
differential equations, integration with respect to force/work done, series,
logistic growth, etc.
I'm sure I'll like it. I get in a real bad mood when I don't get something so I just sit in a hole for a bit unfortunatly and it becomes harder to learn. But now I feel like I'm getting this better.
ah!
nice
series is where shit gets real
oh boi
you find out there are approximations for everything lol
you'll know when you get there lol
does it have any applications to stats
I usually try finding examples to get me exicted if it has a translation to stats
stats relies on approximation... so yes 😛
series allow curve fitting and all that
ah
okie okie
I'd love to go over a disk/washer method but I don't want to take up your time
good luck! glad i could help even though my memory was a bit fuzzy
Na you've been great
key is drawing it out. the more you draw it out, the easier it gets, eventually you wont need to draw.
Sometimes your professors forget what it was like to learn the material so they gloss over some stuff
gotcha
will do
have a good one
you too 🙂
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I want to know what's the best way to decide how to check if a system of linear equations is inconsistent?
for example here, I need to find a value of p so that the system is inconsistent
@modest python Has your question been resolved?
<@&286206848099549185>
@modest python Has your question been resolved?
Do you know what an inconsistent system is?
yes, but I don't know if I should check every existing number for p to know if it give an inconsistency
or if there's a way to know what numbers to check
What does an inconsistent system mean?
when the rank of the augmented matrix is greater than the rank of thematrix
Do you know how to reduce that into REF?
Because having it in that form would help out
like, with Gauss-Jordan?
Solve the last row, you'll see that you'll end up with two values of p
with the augmented matrix?
Yeah, you can just focus on the last row
Yes
If you recall, no solution is when the left side of the bar is all 0s and the right is still some number
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I'm assuming you got it?
hahah yes
And you got?
11
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@feral summit Has your question been resolved?
7 1/4 percent is just 7.25 percent
7 5/8 percent is 7.625 percent
@feral summit
Here’s your equations
Oh
It’s either 32 or 31 dollars depending on where you round
its like 108 or 109 dollars
i would just assume they want you to round after each person
so i would put 109
@feral summit

what did u put on the last question
did u put 31 or 32
@feral summit
i guess its 108 then
32
Bro is a life saver
haha
do understand it now tho
if its fraction just put 7/8 in your calc
you get .875
so its 6.875 percent which just turns into a rate of .06875
ohh
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Could someone please check my work I have a feeling I messed up somewhere
Can u provide the question
Calculate the shortest distance from point C to any point along point along AB
And the points are A(3,5) B(-1,7) C(-7,-3) and D(5,-7)
i would recommend graphing the points on desmos
essentially what you want to do is the following:
- find the equation line connecting A and B
- find the line that is perpendicular to line segment AB such that it passes through C
- find where these lines intersect
- find the distance between the point of intersection and point C -- this will be the answer
Our teacher doesn’t let us use Desmos she wants us to do it by hand
That’s why is so complicated
This is what I get in desmos
I think I messed up one of the equations
@willow bison
sorry i'm a bit busy
you don't need desmos
you can easily graph this by hand
do you know how to find a linear equation using two points?
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@wet holly Sorry to pin, i do have a follow up qeuestion
I am not sure how to argue from -sup(A) = inf(-A) to sup(-A) = -inf(A)
@thorny jungle Has your question been resolved?
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help.
!status
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'm told it's wrong
4. I got an answer and would like my work checked
5. I have a question about someone else's worked solution
6. None of the above
Line EF is the perpendicular bisector of segment BD and the bisector of angle BAC
Only the last option is correct..
BD is a curve hence EF does not form a 90 degrees with it
It says segment BD, which means that it is the line segment between points B and D
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@velvet vine @still temple so what's the answer?
there's probably only two correct options.
(if that helps)
Line EF is the perpendicular bisector of segment BD and line EF is the bisector of angle BAC
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Can anyone numerically confirm my answer is correct?
i've attached work
@worthy spindle Has your question been resolved?
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@worthy spindle Has your question been resolved?
@worthy spindle Has your question been resolved?
<@&286206848099549185> please 🙏
@worthy spindle Has your question been resolved?
It looks like you don’t even need the fact that the staircase is helical, since gravity only works downwards
@worthy spindle Has your question been resolved?
Hello. Yes I agree that the staircase being helical is not really important in this case 🤔. Anyway you should get the correct value as all the components are defined correctly
,w integral from 0 to 120 of (230-2/120 h) dh
Yes it's correct 👍🏽
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f(x+h) = 5/(6-x+h) - f(x)= 5/(6-x)
Common denominators:
f(x+h)= 30-5x/(6-x)(6-x+h) -f(x) = 30-5x+5h/(6-x)(6-x+h)
Subtract:
5h/(6-x)(6-x+h)
Divide by H from the denominator of the function:
Get's the answer : 5/(6-x)(6-x+h)
A Lonely Bean
ohhhhhh
okay
let me try that
After doing that, I get -5 / (6-x-h)(6-x) and it's wrong
f(x+h) = 5/6-x-h - f(x) = 5/6-x
Common Denominators:
30-5x/(6-x-h)(6-x) - f(x)= 30-5x-5h/ (6-x-h)(6-x)
Subtract:
-5h/(6-x-h)(6-x)
Cancel out the h from denominator in the function
-5/(6-x-h)(6-x)
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Separate the sum for 1st one
Then ?
you can use the formulas after seperating
THANK YOU LOL, i already got it but thanks for the response still
Do you have a screen of all the formulas please ?
Or somewhere I can have them
For first one use sum of finite GP, sum of AP I think, then for n-3 it will just n-3 n times so it becomes n^2 - 3n
What does GP mean and AP
Im not familiar with English writings
GP = Geometric Progression
AP = Arithmetic Progression
Ah yeah ok
Thx
Im not sure I really understood
Is that about it ? @brave spire
@wind beacon
Ur doing the sums wrong
Yes
How do I know that
Also the sum of the GP 2^k is not 2^m
The terms of our GP are 2, 4, 8
...
Observe that they are all of the form 1 * 2^k. Comparing with a*r^n, we observe that a=1,r=2,n=k
By sum of GP formula
S_n = a(r^n - 1)/(r-1) = 1(2^n - 1)/(2-1) = 2^n - 1
I don’t need n+1 in thzt ?
It’s good like that ?
Are they good ? @brave spire
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hm
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Helper Rieman ask me this but i was making food
i am surprised to how he is surprised that this cant be
Does anyone think this is OK?
I never said it was wrong
Its derivation
I asked for justification
So the question is to find y(w,p) , but we do that from problem of profit maximisation with y (production) as variable
I also asked for a starting equation
y(w,p) is function of production of a firm in the short run which means r*K is ignored
so first order condition FOC: derivation of profit function by variable (y) in this case must be 0
and from there i start with derivation
Yea you didn't give any of that information earlier
Sorry i thought like just the math part of it i don't know if i got it correct I think it is?
also Pi is profit function
y - Function of supply of producer, w - price of Labour (L) , p - Price of product, Pi - Profit function
😢
i fail to prevail
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i cant understand how to expand this
i dont know how they did that
First they did polynomial division, then they factored the denominator
oh well my bad i shouldve mentioned i factored the denominator fine
its just the top i couldnt figure out what they did
one sec i forget what polynomial division is
ok yeah how do you use polynomial division here?
Example:
So you mean what would be the divisor?
x^2+3x+2, because that's the denominator
Ok
ok could you possibly show me how to start the polynomial division
I'll try to typeset it because I'm not on a phone and I can't take pictures
ok 👍
This looks weird but it's the best I can do
yep exactly! The remainder you can do as (7x + 9)/(x^2 + 3x + 2) and then they factored the denominator to (x + 2)(x + 1)
nice work 🙂
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this was a fantastic example thank you
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Need help on highlighted parts a, d
I would say both are true.
so a linear transformation is the same as a linear function then?
linear would be special for functions i suppose
A linear transformation / linear function is just a function that is linear.
yes generally
Transformation might highlight that it is multidimensional or geoemtrically significant
the word "special" threw me off honestly
I think they just mean that not every function is a linear function
so they are just a special kind of function
d is a bit vague imo
same with a imo lol
if all your spaces are finite then you can represent a linear transformation between them as a matrix transformation
for part D this is all that is said
whether you interpet that as saying they are matrix transformations is ehh
ehhh, you can do infinite matrices kinda.
you wouldnt really call it a matrix at that point
Depends on your definitions.
I have definitely seen people call them matrices.
Either way it seems pendatic.
so every matrix transformation is a linear one, but its not always true in reverse?
thats confusing as hell
id be interested in those examples
Either they do exclude infinite matrices or perhaps they want specifically a representation.
You can definitiely write a mapping that does not look like a matrix representation at all.
Today I alrady helped one that wanted the matrix representation of the polynomial mapping phi(P) = P(X + a).
alright, settle down boys this is chapter 1 of my LA book lol
One can argue that without a basis that it is not yet a matrix transformation.
im trying to find those examples for you though
yeah it'll likely just be an abstract linear map on two vec spaces
so idk if the terminology went over my head but i went through the examples in chapt 4 and 5 and none specifically said it was an example of a linear transformation that wasnt a matrix transformation.
whats the book?
lol
David Lay - Linear Algebra and its Applications
The thing I can tell you for sure though is, that if you do fix a basis, then you always REWRITE any linear mapping as a matrix mutliplication.
ISBN 10: 0-321-38517-9```
If you have infinite dimensional vector spaces in your mapping then the matrix will of course also be infinite.
at this point we haven't covered basis, determinants, subspaces, or any of that yet
ah...
this is still chapter 1
short outlook then.
In the more general sense, people call anything a vector space that has linearity properties.
are there spaces where linearity is impossible?
In some cases you might not be able to have a natural vector representation.
A basis is just you choose some predfined vectors and use them as your stating point to put together any other vector with them.
so would
[ 1 0 ]
[ 0 1 ]
be the basis for the cartesian coordinates?
Like you can put together any vector in 2d real space with the standard basis (1, 0) and (0, 1).
yeah exactly.
You could also use (0, 1) and (128738, 123873137812387) though 
this is an example of an extremely high dimensional vector space
so, the book doesn't really justify the statement that every matrix transformation is a linear transformation, but states it anyway. what would i put as a justification?
If I was feeling snarky I would say "I think so yes because... but the book says no on page X" 
Yeah I would probably just point at the page.

wait
I am reading there will be counter examples in chapters 4 and 5
so every matrix transformation is a linear transformation, but not every linear transformation is a matrix transformation
but again, it doesn't really explain why that is besides a "trust us, or read chapter 4 and 5"
yeah
It's probably either the basis thing or the dimension thing.
It's really just terminology.
I can guatantee you that later on if you do more advanced mathematics people are not going to obsess over this distinction.
honestly the terminology is already confusing in chapter 1, theres like 5 different ways to say things already

no problem and good luck
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I need help please
I don’t know how to do this cause my teacher didn’t specify, if anyone is familiar with the topic please help me :,))
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@narrow mural Has your question been resolved?
@narrow mural Would you be comfortable describing the volume of those two boxes?
the space that needs to be filled with styrofoam is (volume of big box) - (volume of small box)
well that is the whole thing for the first question
hm, this is a difference of cubes
I mean literally, it's two boxes that are cubes
and also mathematically, those are both perfect cubes
I bet you have a formula for sum/difference of cubes
I do
I need to answer what the a= and b= how do I solve this or what should I put
well
your a^3 is 1728
so what is a?
like, what did you cube to get 1728 in the first place?
12^3
x
yep, a = 12, b = x
waiting
no problem 👍 glad it helped
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I don’t know how to continue the problem
From -12 < x - 6 < -10 you can imply that |x - 6| < 12
So you have |x - 6||x + 5| < 12|x + 5|
And with correct delta you can make 12|x + 5| < epsilon
so would on the left side would i choose |x+5| <12eplison?
epsilon/12 perhaps?
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hello
I am having some trouble here
Like i know cube root for these numbers
is 3 and 5
What is the question
is this a test?
Ok so you know that 3^3=27 and 5^3=125
No is my home work
Yes i do
A test wouldnt have the options of ask your teach and need help etc i guess
then what is (3^3)*s^3
Dyssrupt
Ah this formula
exponent rules are not required here
But to get 3s^3
Oh
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