#help-23
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And that would become sqrt(t + 3) right
But there’s still the 1/2 that I put in front
Yeah, but the sqrt(t+3) would be in the denominator
Oh do I just separate it in another fraction?
I wouldn't do anything
you generally don't need to simplify it too much
just get the derivative right and move on
There are a billion ways to simplify, generally combining constants/negative signs and getting rid of negative exponents is sufficient
I would love to keep it like that but the answer in the text book looks really simplified
Does the textbook have a sqrt(t+3) on the denominator?
2 sqrt(t + 3)^3
give me a second
Here’s the answer
Either the derivative is wrong or the answer key is
simplifyig gives you 38t^3 and +1, not -1.
What did you do?
multiply both sides by 2sqrt(t+3) and then combine'
Do you still have what you’ve written down
Maybe we could see if there’s a mistake or something
found it
you made a mistake on the quotient rule
the sign seperating u'v and uv' is supposed to be a (-), not (+)
lemme write it out
Why did you multiply 2 sqrt(t + 3)?
Is it so you can get rid of it that fraction in the numerator?
yes
3x6x2
When we multiplied both sides by 2sqrt(t+3), we distributed it over the - sign on the numerator
Like a(b-c) = ab-ac
I noticed that the sqrt(t+3) isn’t there anymore
Yup
Since sqrt(t+3) * sqrt(t+3) = t+3
Yeah I just multiplied all the constants together and moved them to the left
@karmic zealot Has your question been resolved?
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I’m unsure where I’ve gone wrong. My question is what are the transformations, ie question 4
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Hello, I need help in Linear Algebra 2.
I have a test coming up and theres some theorems I need to prove for the test.
For instance:
For all A, matrix of size nxn, and a polynomial c(x):
c(A) = 0 => m_A(x) | c(x)
Such that m_A(x) is the minimal polynomial.
I dont really know how to do that, could someone help
@solemn ridge Has your question been resolved?
Assume the opposite. Let p(x) = q(x)*m(x) + r(x) with deg r(x) <= deg m(x). We basically do long division by the minimal polynomial with q(x) as the quotient and a non vanishing rest r(x)
Now try to get a contradiction from it
I understand. We got r(A) = 0, in contradiction to the fact the m_A is minimal. Thank you!
That was quick!
Well done
Thank you!
I have another theorem that I couldnt prove.
If T is a Linear map on C, then:
forall u: <Tu, u> = 0 iff T=0
I thought about doing something like:
<T(u+v), u+v> = <Tu, v> + <Tv, u> = 0
And then maybe try for i*u and sat something like
<Tv, iu> + <Tiu, v> = 0
But I dont really know how to continue
Oh wait if I say that this implies:
<Tv, iu> = -i<Tu,v>
<Tv, u> = <Tu, v>
Then if I would say for v = Tu
0 = <TTu, Tu> = <Tu, Tu>
=> Tu = 0
I got it
Thank you!
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Sorry that this is messy but can someone help me out on what I did that is wrong please
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help
,w 3+3
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hello, let's say i have a graph of the form y = 1/x
just the positive part
is there a way for me to change the axes so that it becomes a straight line y = mx + b
like a log plot but not a log plot
you could plot it against 1/x
plotting against log x is nothing but a function of x
1/x is also a function of x
but it'll break at 0
yes
ok thank you
it'll break because it wasn't in the original function
so after resizing the axis it still wont exist
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help to solve 14 please
ok so given that x = 5i is a root, which other root do we instantly know
1?
no
which method easy to solve this?
because im confused when solving with synthetic division
Is there a proof for that thing btw
notice how you can do factoring by grouping
I can think of two possible methods, you either first state some of the roots and factorise/algebraic division to find the remaining factor of f(x) to find the root. Or you use the relationship between the sum/product of roots and coefficients of polynomial
what do you end up with
proof of that if we know that x = 5i is a root then x = -5i is another root?
Yes
Like idk why that should make sense
they come from a quadratic term
so
(x-1) (x^2+25)
Im guessing it lets you create the (x^2+25) root if you wanted to use long division to get (x-1)
ok
most likely that ye
sometimes it's not so easy to spot the factorisation of f(x), and x = 5i tells you the factor (x^2+25) and makes things easier
alright
yeah the imaginary roots being given helps a lot more with quartics and ones after it
since factoring those is horrid
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how are these two the same
can you factor out 12 and 48 from the surd?
dont understand
ok I'll show you an example, see if you get it. sqrt(20) = sqrt(4 x 5) = sqrt(4) x sqrt(5) = 2 x sqrt(5). Does this make sense
but how we getting 36
well given the example I've shown you, can you simplify sqrt(12)?
2* sqrt(3)?
16*sqrt (3)
nope, slight mistake there
48 = 16 * 3
so sqrt(48) = sqrt(16) * sqrt(3)
which is?
4* sqrt (3)
now add sqrt(12) and sqrt(48)
thx
np
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any issues with my description here?
co-linear has a span of R^1
co-planar has a span of R^2
the red arrow indicates "breaking out" of co-linear and co-planar with a single linearly independent vector
all it needs is one vector to give a co-linear system a full span of R^2
and all it needs is one vector to give a co-planar system a full span of R^3
@fickle trail Has your question been resolved?
you are confusing "1-dimensional span" with "span of R^1"
vectors which live in R^2 or R^3 can never span R^1
vectors in R^3 can span a plane (aka a 2-dimensional space) but can never span R^2
oh good catch on the wording
that's right
do we call that a sub span instead?
"1 dimensional span" vs "span of R^1", can easily get these confused
we dont really call anything a sub span. I dont know what you want to mean with that
OK
the span will be a subspace of whatever space you are in
span just refers to linearly independence
no
wait lemme rephrase that
span just refers to vectors and if they are dependent or independent. this will indicate what areas they can reach, so we call that the span
the span of some vectors is the set of all linear combinations of those vectors
having one extra vector going rogue, as i have indicated with the red arrows, can reach anywhere in a higher dimension
when i say rogue i mean linear independence in a meaningful way where the other vectors can reproduce it somehow
wait maybe that's wrong, to say "anywhere"
it's any distance in a straight line, isn't it
we can't change the angle of that line
but we say that it fully spans because of that red arrow
whereas before it was limited to a smaller span as each vector was parallel to one another in the same direction
dang this stuff is hard to explain, words blend into one another, mumble jumble, gotta be super careful about wording
if we don't say sub span
do we say full span?
and not full span?
or the R value indicates that
spans R^3
spans R^2
what
based on the vectors provided
let's say 3 entries each vector
we know it's R^3
but span is only R^2 because of parallel lines
the span of vectors that are in R^3 is NEVER R^2
i don't understand, in my example above I stated that
the span can be a 2-dimensional plane, but it can never be R^2
but this is correct:
the way this is worded
it's exactly word for word how the instructor said it
with the a, b example
yes thats correct. but in that example a and b live in R^2
so at least in theory they could span R^2
but if they live in R^3 they can never span R^2
no matter whether they are linearly independent or not
so what's the point of span? if it's just gonna equal the same as the dimension
even co-planar is span of R^3
a span of things by definition is a subspace
when we say span = R^2 or span = R^3
the span is a plane in R^3 but not R^3
a span of things is a set. a dimension is a number
they cant be the same
confused right now
so the way i worded it is technically incorrect
lemme reword to see if i get it
one sec
well i mean
oh
so i was kinda correct to begin with
spans R^3
but i forgot to say subspace of R^3
you cant say you were correct when you wrote something wrong down
tyvm
is this a better way to word everything?
no need to write "full" but just to be extra clear
not a subspace for the examples on the right
i think thats ok
ty ty
have you watched 3blue1brown's linear algebra series
finally i think i am starting to get it
i have but actually I am finding this course much better
why?
3B1B can be quite advanced sometimes for beginners
well, i have watched them, and i can say for myself, but i we all learn differently
not saying they are bad
but to each their own
I told you last time that ℝ² and ℝ³ has nothing in common ie empty intersection
sorry it must have been late didn't mean to jet i think i got afk
If you took things in ℝ³ and took its span you never get anything in ℝ²
ah OK
do you pause the videos to think
yes
The dimensions of the span can be 2 or 3
and I re-watch
Or 0 or 1
hmm ok
But they aren’t exactly ℝ²
but sometimes it just doesn't click
i think the Krista King videos are doing that for me, could just be right place at right time though
maybe starting out it would be different
Watch whatever helps you more
yeah, exactly. i'm 100% sure if i go back to 3B1B there is still lots to learn
even for highly skilled people in math, lots to learn from 3B1B i think
but it can be a bit over the head if you just don't follow, or not seeing it, that just comes with practice and deeper comprehension i guess
i learnt about span through 3b1b im pretty sure
like for you it might be insane, but for me I'm just speaking the truth
yeah ok i get that
all good, one of the great things about learning is each new student is like a fresh take on things, asking "why is that?" or "could it be this way?"
and actually teaching helps us to learn too
like a fresh slate to really not take anything for granted
the learning never ends
for me personally i find this Udemy course super helpful
and ChatGPT (lol, I know) for basic questions, not with math problem solving but for bigger picture abstract stuff I find it quite helpful indeed
and Math Discord is great when I wanna try to explain it, learning and doing can sometimes be quite different from explaining
what i think is correct, someone will always be happy to point out a flaw haha
it's the only way to get better
tyvm folks, appreciate it!
sometimes i wish i had the humility for that
for what?
.
oh, it can be painful sometimes yeah, you sometimes question if the person answering even knows what they are talking about lol
if you know it well enough you can explain why you think their answer is incorrect
but most of the time I'm perfectly OK with just "I don't know", and "let's learn more"
ah sorry my english is all over the place
you know what i dont remember what i wanted to say
its 2 am
thats enough math for a day
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Hello I struggle to a question: For which value of the real "a" this polynomial admit a multiple real root?
do you know descarte's rule of signs?
No what is it?
I tried to set P=0 and P' =0 as a system and solve it but i did a mess
basically, the number of times the sign of the coefficient changes in P(+x) gives the maximum number of positive roots and vice versa
you can also try by P<0 and P>0 for some specific values, you'll get a range of a. (since this is a continuous function)
If i understood good the Descarte's rule make you find the number of roots
But i need to find the value of a that make P admit a multiple real root
Idk how this rule will help me
have you tried vieta's formulas?
cause for sure we know that there are exactly 4 root (real or not)
we want to have a multiple real roots
so we can eliminate a case with 0 real roots and only 1 real root
so then we have 2/3 or 4 real roots and maybe we can do sth with that
with vieta formulas we get
- r1 + r2 + r3 + r4 = -4/1 = -4
- r1r2 + ... + r3r4 = 8/1 = 8
- r1r2r3 + ... + r2r3r4 = -16
- r1r2r3*r4 = a
where r1, r2, r3, r4 are roots
Its the first time i hear about it let me check this
So a is the product of all roots?
yeah
No way
i know
It is this easy
i'll be trivial here (no rules, just basic math)
we need multiple roots, we can clearly see that if a=0, x=0 will be a root. lets say a<0 or P(0) < 0
P(-1) = -11 + a
P(-2) = -16 + a
P (0) = a
P (1) = 29 + a
P( -4) = 64 + a
lets say a>-64
then P(-4) > 0
P(-3) = -3 + a < 0
so it has multiple roots in this case because P will be positive for sure after some after x>3
cool right
ah should have just done that lol, much easy
completely out of my mind even though i have done many questions like that
Lmao how in the world never have i heard abt this cheat
Thanks a lot it sures help me
Ill try it too so ill train lmao thanks all of u
it wont be helpful here but in questions where you have to find out the number of roots when you know nothing about the function, you can remember this trivial method
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n is an odd natural
u = e^(1/(2n) * 2πi)
can someone verify this identity real quick (i.e. both are equal for all complex x)
work shown in https://www.desmos.com/calculator/omvx6dqycn, but refrain from revealing spoilers until I verify that this "approach" is valid
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Guys, isn’t cos(2x) = sin^2(x) - cos^2(x)?
And if so, can’t I use the golden rule to make different rules out of that?
It's not.
what is it then?
Your RHS needs to be negative of what you have written.
So cos^2(x)-sin^2(x)
Yes
Thanks
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Vectors x and y are each have a length of 3 units. If |x+y| = square root 17, find |x-y|
How do I ger started
use the identity for square of a modulus
axxy
@modest rain
use this information
62 degrees
hm let me verify
also u dont need the degree
just find cos(x)
the ratio
whats ur ratio?
17/36
Let me think

$17-18 = 18cos(x)$
axxy
$-1 = 18cosx$
axxy
$-1/18 = cosx$
axxy
Oh got it I got my algerbra wrong
okay so we found the ratio right?
now we want
|x-y|
can u deduce an expression for $|x-y|^2$
axxy
similar to $|x+y|^2$
axxy
Does one length become -3?
no
the new expression just negates the cosine term
now input the values and square root both sides to find |a-b|
square root 19
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also nice pfp
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Idk if i set it up right either
hmmm, what is page 42 about? the usual way is called Heron's Formula and is really complicated
It’s the same set up but just different numbers
do they use the heron formula or some weird trig thing
Some weird trig thing which I don’t get 😭

I think you just have to follow what the book does but with different numbers, there are a lot of ways of doing it
👍
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if m and n are positive integers with m>1,then n<m^n
I think Induction does it but I get that m^n≥n+1 and would have to show m^n ≠ n+1
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I now know how to solve to get angle B, but how do you solve for angle A and C?
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@rose ether Has your question been resolved?
Cosine rule
And sine rule
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how do you calculate x?
yes?
(Sin of angle A)/side a = (sin of angle B)/b
Label angle A the 35 because it has a corresponding side
that is already defined for you
so side a = 12
Angle A= 35°
Ultimately the side that corresponds to 27 doesn’t matter
The reason 27 is there is so you can calculate the last angle
The sum of a Triangle’s interior angles = 180°
Knowing that two of the interior angles are 35° and 27° you can figure out the last angle
No
So with the information that is given to you and knowing that the sum of the interior angles =180° find the 3rd angle
is the third angle 118?
hold on gimme one second
Yes
It is
now you know the 3rd angle
Now you know all the information needed to plug into the formula
^
sin(35)/12 = sin(118)/b?
how do i do that? sorry 😭
thank you! :)
so you multiply both sides by b
Then divide both sides by sin 35°/12
When dividing by a fraction skip flip multiply
(flip the fraction upside down and multiply)
Now you have b alone
Just solve and you find the final side
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helo
Please don't occupy multiple help channels.
@random topaz Has your question been resolved?
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Can someone help me/give me a clue on why f(γ_1(t)) and f(γ_2(t)) meet at f(z_0) with angle pi? Thanks in advance!
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<@&286206848099549185>
$z_0 + t = z_0 + it \implies 0 = t(i - 1) \implies t = 0$
south
And also look at the direction vectors: t makes an angle of pi/2 with it
From the definition of i
ty for responding, and yh I'm convinced about that part
No worries
Ah shit
Okay it's cause cosh(it) = cos(t)
$\cosh t = \frac{e^t + e^{-t}}{2}, \cos t = \frac{e^{it} + e^{-it}}{2}$
south
right so cos(t) = cosh(it) / cosh(t) = cos(it) [both are true], taking cosh(t) = cos(it), we're trying the find the angle where cos(it) meet cos(t) essentially. I feel like I'm missing smth obvs that tells me the angle for that is pi
True I can't figure it out either
haha thx for helping though, I thought I was missing smth really simple (maybe it is who knows XD)
still need help with this
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Can someone please go over how to set up the equation for this problem, I'm not sure where to start
you have the choice of either disk method or shell method
I'm not sure which is which 😓
I think in class we called it the washing machine method
washer method?
Yeah
that's same as disk I think
ok
disk method is a special case of the washer method (the hardware, not the machine)
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Given two objects, one possess a mass of m_1 and kinetic energy of k_1 while the other possess a mass of m_2 and is stationary, have a head-on elastic collision. Then in what configuration will the transformed kinetic energy from the m_1 object to the M_2 object to be the greatest?
there's five options
I would like someone to check my approach which contributes to a wrong answer
After some analyses, I realized that v_2 and k_2 are in direct proportion as well as k_2 and m_2.
Despite both v_2 and m_2 are in direct proportion with k_2, the ascending trend of k_2 = v_2 is more significant to its counterpart k_2 = m_2. It is due to the difference between linear relations and quadratic relations between them.
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<@&268886789983436800> drunk man spotted
ain't the result indicates k_2 has its maximum when the value of m_2 can no more be greater than m_1.
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Does anyone know what f(u) should be if its not ln(u)/5u ?
Would you not let u = t^5 + 26 and then have du/5 = t^4 dt
Which would end up with that
Because its wrong on my hw
yeah that looks correct lol
@iron basin Has your question been resolved?
Thats so stupid i had a perfect hw grade in this class so far and if i check the solution or regenerate a problem it takes partial credit
I feel like i have to be missing something but i have no idea
The final answer at the end of the problem was correct so i dont know
Maybe the way we write it, can you separate the factor of (1/5) in another bracket
I tried that too it still counted it as wrong
Yeah then it's the website
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95% confidence
I believe this should be 2 standard deviations from mu right?
right
your variance is 3.2^2
wouldn't it be z=1.96, because you have to consider both sides of the distribution?
yes
confidence interval is $\mu\pm Z^{}\frac{\sigma}{\sqrt{n}}$ and you want to differ from the mean by 1, so the $Z^{}\frac{\sigma}{\sqrt{n}}$ term should be 1, you know $\sigma$ and $Z^*_{95}$ so solving for $n$ is trivial
PajamaMamaLlama
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Hello
so I've been messing around with some models and ideas, and I've come up with a function v that "should satisfy these criteria"
let F be the set of all functions from the natural numbers to the 3d euclidean space
then v is a strictly concave function from F to the reals
is there any sense in which such a function, possibly with other constraints, could be "optimised"?
(I wanna find a global maximum)
<@&286206848099549185> ?
also, I should say that I have absolutely no idea about the specific form of the function beyond concavity for now
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uh natural numbers to 3d real space sounds unworkable, but in general yea you just need convex functions to optimize stuff https://en.wikipedia.org/wiki/Convex_optimization
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Minor thing that might help you find literature on this topic. A function that maps another function to a number is a generally called a "functional." @raven atlas
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How do I do this sort of thing? This is homework and if I get it wrong I can try again.
that's correct just put the -6 in front since you divided by it
help me
Given an infinite set of X1+X2.... Xn. How much is Xn!
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This is occupied
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so im trying to show that this is true
there's 2 statements here (iff), if Y and h are measurable functions then clearly the composition of them h after Y is also measurable and we can call this Z and it's measruable
now if Y and Z are measurable functions, how do i show that Z after Y^-1 is measurable
in particular, $\forall \delta \in \sigma(Z), \text{preim}_{Y^{-1}}(\delta)\in \mathcal G$
Frosst
okay hold up we have that $\sigma(Z) \subseteq \sigma(Y)$
Frosst
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I am a tad bit confused: The diagram on the bottom has the the arrow for h going the wrong direction
Which one, the diagram or the domain/codomain of h?
ah i see
Alright, the forward direction is clear; composition of measurable functions is measurable
Do we require commutativity of that diagram? Otherwise the statement as written is trivially true.
The diagram is just for me to see what is being written
I’m trying to show the 2 statements above
The one connecting the iff
This is the original statement if you want to see if I’ve mistranslated it
Ok yeah we require commutativity of the diagram. As written on the board, you only require the existence of measurable functions, which are trivially satisfied by constants.
It's not an existence statement for Z, just for h
But it says iff
right, but you are given Z already
The iff only concerns the measurability of Z
Oh I’m misinterpreting
I see
So it’s more like this
And the existence of h forces the diagram to commute?
Right
Because then Z is just the composition of h after Y
the top condition is missing a piece, it's required that Z = h o Y
Hmm
Ah because h after Y is indeed a measurable function from σ(Y)
But my Z could be some other thing completely unrelated
So we need to force the Z to be actually that composition
Then if a measurable h can be found then Z is composed of measurable functions
No, the statement is saying that Z is measurable iff there is a measurable h such that the diagram commutes.
The commutativity is required for h here.
If I can’t find a measurable h then it’s not measurable? How do I show then that Z is also not measurable for sure
Yeah I’m saying this is why me missing the restriction for Z is wrong
Ah I see
I think you should be able to do it via characteristic functions
Suppose that $Z = \chi_{Y^{-1}(E)}$ for some $E \in \mathcal{G}$; then $h = \chi_E : (\Lambda, \mathcal{G}) \to (\mathbb{R}^k, \mathcal{B}^k)$ is measurable and $\chi_{Y^{-1}(E)} = Z = h \circ Y = \chi_E \circ Y$
LJ NG+
So for any measurable Z, write Z as a limit of simple functions and show that the resulting sequence of measurable h you get converges.
You may need to first write Z = Z^+ - Z^- for this, taking the positive and negative parts of Z.
let me think about this
this is a good one
you have to construct the function
its a fun construction
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I’ve cheated
My second book has a proof
It does not look as though I would’ve been able to come up with this
<@&268886789983436800> 1122830721195716639
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Given A,B,C, and X are all 2 by 2 matrix
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Given A,B,C, and X are all 2 by 2 matrix
And
answer the questions below:
If XC=CX, then what possible matrices could X be?
wow chinese
I would write X as a b c d then just do the matrix multiplication
the 4th one is the identity so its one of the solutions
That's quite a straightforward and efficient solution
its tedious if youre doing it a lot but yeah
what do you mean by "identity"? I cannot seems to understand it.
identity matrix, any matrix multiplied to it is itself
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Hi
the right side is equal to this
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What are the rules for multiplying Matrixes?
Something simple like this?
Use Dot product rule
in the most general form, take the ith row of the first matrix (starting from the top) and dot product it with the jth column of the second matrix (starting from the left)
this gives you the entry for the ith row, jth column of the product AB
now... what does that mean?
@normal rose take the first row of A and dot product it with the first column of B
hmm
that gives you the first row first column entry of AB
so 8* -5 and 1*7?
-40 + 7 = -33
and that's the first term? or do i keep it as -40 + 7?
so first row by first column
second row by first column next?
first row by first column
first row by second column
second row by first column
second row by second column?
yes!
that gives you the entries for the
first row, first column
first row, second column
second row, first column
second row, second column
of the matrix AB, respectively

it's .close
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what's the question
find square
square?
yea?
yea
you don't really need integration here
you can find the area of the trapezium formed between the line and the axis
but when i use integrate i get different response
integration
ill do it both ways
if you find the trapezium area
the height is 7 and the sum of parallel sides is 11
so the area is 1/2(7)(11) which is 77/2
38.5
now using integration
the equation is y = 5/7 x + 3
integrate that you get 5/14 x^2 + 3x
plug in 7 you get 35/2 + 21
which is 17.5 + 21 which is 38.5
same answer
the gradient is change in y/change in x
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so this is equivalent to integrating between -pi/2 and 3pi/2 right?
if not I fear this will be rather nasty
will require IBP multiple tomes
*times
cant u just do a triangle diagram or smth
the integrand becomes pi/2 - x or smth right
just pi/2 - x no?
domain restrictions are still in effect
idk, check if im right
ye
didn't notice the arccos 💀
hmm, so this would be π-x in (pi/2,pi), right?
but yeah all there is to this question is to think of what arccos(sinx) is geometrically
how did you get this? also no
then what would it be
sin(π-x)=sin(x)
is what I used
I'll do this later
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quick question for vector product
lol
$\hat i$ iirc
Denascite
it's just about this
kheerii
then $|a\times b|=a_1 b_2 - a_2 b_1$ yes
kheerii
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can you guys help me with this?
what will be the annswer
?
when i say it is decaying 0.45% every month it says its wrong . idk why?
because it's not every month
t is in months, but the exponent is t/30
so you won't have a decay of .45% until the exponent 1
so what would it be?
when is t/30 = 1?
when t is 30
so it decays .45% every 30 months, or 2.5 years
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On the slopes AB and CD of the trapezoid ABCD, the points M and N are chosen such that MN||BC and AM:MB=3:4. Find the length of segment MN if the lengths of the bases are 8cm and 22cm (AD is the larger base)
@cyan sorrel Has your question been resolved?
a parallel line along a trapezoid, when you move it around, gets bigger and smaller at a constant rate
so if you go from the top to the bottom you're just stretching from 22 to 8
and 3:4 means you want a number which is slightly closer to 22, 3/7 of the way to 22=AD
like red is where the answer is on a number line
so try to find out how much 1/7 of the distance is and move 3 of those from 22 for the answer
yea the proportion is 3:4 between 22 and 8
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If a(a1, a2) and b(b1, b2), axb=a1b2-a2b1 then what is a(a1, a2, a3), b(b1, b2, b3) axb?
as product
$\begin{vmatrix} i & j & k \ a_1 & a_2 & a_3 \ b_1 & b_2 & b_3 \end{vmatrix}$
TayBee
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Can someone please help me simplify this
uh that's not exactly correct cuz
the hypotenuse squared = a^2 + b^2
in this case the hypotenuse is x+10
not x
Wait
OHHHH
hold up
So it would be
(X+10)^2 = 14^2 + x^2 ?
I somehow forgot how to do x+10^2
Could you help me out please 😭😭
faiyrose
faiyrose
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reaction for more information.
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So it’s x^2 + 20x + 100 ?
⚔️
Awesome thank you so much so I think the answer is x = 4.8 ?
Epiccc thank you so very much!!
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always try and simplify
it doesnt have real solutions you know it?
yes
😲 i wonder why im here then
i tried i failed why else am i here
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does this diverge or converge?
Do the terms go to 0 ?
If so, how?
Monotonically?
Fast enough for convergence to be absolute?
i don't think it is monotonic
when I did the ratio test I got that it diverges but on my answer key itdiverges

"I got diverges but I should have gotten diverges"
Except it converges
ssorry it is a typo
yes on the answer key it converges but I don't understand why
the series doesn't go to 0, it isn't monotonic, and it is fast enough to be absolute
ratio test harder
are you ratio testing by looking at the quotient of consecutive partial sums?
no
i don't think so
oh thank you
u split it into two fractions bc same denominator
i mean one fraction
the ratio of two consecutive terms goes to -1/2 by a simple computation?
what do you mean by that?
*better
does 2n+3 cancel out 2n+1 because they are basically the same except 2n+3 is just one terms ahead of 2n+1
kinda like a factorial?
they ratio goes to 1
You're just doing a computation
Don't overthink this
(2n+1) / (2n+3) = ((2n+3) - 2) / (2n+3) = 1 - 2/(2n+3) -> 1 - 0
oKay I understand that, but how would that fully simplify the limit when doing the ratio test?
have you tried just writing it out and simplifying just about everything ?
let me try again
causd ehen I do it seems to get more complex
oKay I got it
lomit goes to 1/2
thank you
.closs
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