#help-38
1 messages · Page 190 of 1
Wtf I'm so confused
(1 0 0) is an eigenvector for the eigenvalue 0
(0 0 1) is not an eigenvector
Ok
since M * (0 0 1) is not a multiple of (0 0 1)
U said any multiple of (1 0 0) maps to (0 0 0) ...how
M * (x * (1 0 0)) = x * (M * (1 0 0)) = x * (0 0 0) = (0 0 0)
M * (1 0 0) gives you the first column of M
Which is filled with 0s
M is a matrix mate
So isnt it x + 0 + 0
Oh wait
x + 0 + 0 =0
Which gives x=0
That's big brain
Thanks for help
I will juz do more practice
I'm a bit confused what you refer to with x + 0 + 0 = 0
but M * (x * (1 0 0)) = x * (M * (1 0 0)) = x * (0 0 0) = (0 0 0) describes why any multiple of (1 0 0) maps to the zero vector
likewise by arguing with the first column of M
Ya
yea
Why can't I use the same logic as x
wdym by that
How did u get 110
by multiplying M with (0 0 1)
Okok
I also want to briefly point out how you could've checked your previous answer from the former task
Thanks for the help 
Wut the
which would also give you the same result as your calc
I use y' synonymous to dy/dt btw
Yeah having the eigenvectors doesn't help very much in the first place tbf, you have a jordan block already
You still have to solve the system explicitly either way
Why did e-t get differentiated
here?
Woah
You've seen integrating factors ?
That's what lunatic did

nywys gl with further tasks and come back any time 🦩
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Do we not have a formula for the sum of the first m odd numbers raised to the power k?
I am trying to derive a formula, by binomial expanding (2j-1)^k but uhh I don't see anything good
Generating function of this is e^z(e^2zm -1)/(e^2z -1)
But again, can't derive anything useful from here
Maybe you could make use of just taking out the first m even numbers from faulhabers formula, since they have a common factor of 2^k?
Ehh yes that's a good idea let me try that
It worked, tyvm!
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can someone explain how you do this
i thought of doing something like this:
$\begin{pmatrix} 1 & 1 & 1 & 1 \ -1 & 1 & 1 & 2 \ 1 & 0 & 1 & 1 \end{pmatrix} \begin{pmatrix} a \ b \ c \ d \end{pmatrix} = \begin{pmatrix} x \ y \ z \end{pmatrix}$
carburetor
and then solving for all x, y, z satisfying the equation
but i'm not sure how to proceed from here
also, $W + U = { w + u : w \in W, u \in U }$
carburetor
What is LS(…)?
First time seeing that
Me too
Row reduce that matrix augmented with zero vector, if there is a single column without a pivot then it spans R^3
For the intersection one, just equate the linear combinations of each span
@fair beacon Has your question been resolved?
can you explain why this works?
i don't understand why you augment it with the zero vector
Ax = 0
if the RREF(A) has a single column without a pivot then there only exists the trivial solution x = 0
that would mean that the column vectors are independent right
but is that enough to say that it spans R^3?
Three of the columns are linearly independent. That's not enough to say it spans R^3?
oh right got it
Augmented because of the definition of LI
yeah i got it, you're finding solutions to Ax = 0 if i'm not wrong
yep, i got that one thank you
i have one more question if you don't mind
in this case, you don't need to actually find the set of solutions, it's more of a notation thing
sure
can we apply rank-nullity theorem here?
i was thinking of defining a transformation T : R^5 -> LS((1 1 1 1 1)) as T(x) = Ax then by rank-nullity dim(Image(t)) + dim(ker(T)) = 5 but rank(T) = 1 so dim(ker(T)) = 4?
Why is T mapping from R^5 to <1,1,1,1,1>?
that can't be defined as Ax since A maps R^5 -> R^2
mhmm
and also is there a way of doing this without using rank-nullity?
rank-nullity is the best to reason about it
Im not sure of a way that isn't implicitly using rank-nullity
oh alright
because this problem set was given before the theorem was introduced to us
I think now that you put rank-nullity in my head it' s all i can think about
let me see
I mean ultimately you know you are going from R^5 to R^2 so you will be losing at least 3 dimensions
yeah
but again, saying that is pretty much leading to rank-nullity
i have a tutorial on tuesday where they'll discuss this pset and if they show a method that doesn't involve rank-nullity directly i will let you know 👍
thank you very much
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how do i find the surface area of this leaf?
its a special leaf called string-of-pearls and im trying to find its surface area but the problem is the formula is obv 4pir^2 but if i measure the distance from center to the rightmost edge (from this angle) i will be measuring the arc length
so hwo can i find the surface area given that
assume it spherical and measure its diameter would be the simplest way to go about it🤔
wait is it like flat or a bit spherical
its almost spherical
but how do i find diameter
if im only able to measure the arc lengths
yes thesee
Looks like grapes fr
easiest would be using a ruler on the edges
like vernier callipers
Idk maybe you could do surface area of revolution
is there a mathematical way to do it? this is part of a larger thing im doing where im trying to use calculsu to find the surface areas of leaves and see if its correlated ot the tree heights
this is more of an ellipsoid. Try to find the length of the semi-major, semi-minor, and intermediate semi-axis radii and calculate the area from that
oh yeah
i have it graphed in geogebra
could you help me
Mean there's a lot of estimates you could do ig
depending on how much you want to estimate, this would also work
i have it kinda centered around the origin here
no this wouldn't work
cuz i want to use calculus for it as much as possible
Then just surface area of revolution then
Maybe you'd want a different angle
its assuming its a perfect sphere right
No not that it's a perfect sphere
As aero said it's more of an ellipsoid
Time consuming ish
yeah lol actually its part of a larger project im doing
Why you doing this anyway
for my hs i need to have an "internal investigation" on something we like applying the math we learned lol
just
so i like biology so i thought this would be cool
assume it spherical vro 🙏
sure
js to be accurate as possible and not oversimplify
But that'd be too eas-
cuz i gain marks for making assumptions as long as i back it up
Also these def aren't spheres
just so you know that surface area of an ellipsoid is... a bit difficult than a sphere
if i have this, then for surface area of elipsiloid what could i do
Just a teeny bit
It's fine
What could go wro-
i would mark out the points on the upper side of the x axis that are like the "edges" of the leaf right?
I mea-
4pi*r^2
this is perfect
💀
i knew my ia was going to be too easy lmao
i acc did another leaf before and that was a lot of pages
so this is going to be enough to set up the rest of the lab i feel like
i mean, uh, good luck i guess
it's such a small leaf too assuming it spherical wouldn't change the values that much-
unless you want to be rigorous...
I mean what do you even need this surface area for anyway
What is the purpose of calculating this
solid area of rev
i think
Covered
Rip
well my research question was "does the surface area of a leaf correlate to the height of the tree" since in my biology textbook it said taller trees typically compete for sunlight by having larger leaves so it would explain the adaptation
but obv its not true for all cases
and thats kind of waht im trying to see
I mean in that case ig you might need to be kinda exact
complex equations always leads to more marks though right 💀
it used matrices and i had a lot to explain with polynomial interpolation and vandermonde matrix
hopefully
😭
thats awesome
but also rn could i get some pointers on where to start with the surface area of revolution stuff
assuming its an ellipse
whats like the first thing i should do once i have it in geogebra
is the first step to create an equation that is like (x)^2 + (y)^2 = 1
@tardy ledge Has your question been resolved?
@tardy ledge Has your question been resolved?
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Can anyone help me, I’m stuck.
@hallow bluff Has your question been resolved?
<@&286206848099549185>
Notice something
How exactly do I draw the lines? Any specific point on AB and AD?
okay I see it now.
So how do we make it so <LPA = <CPB?
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i need some help here
,rccw
$\lim_{x\to 2} \left(2x\sqrt{\frac{x}{x-2}}-x\right)$
Bonk
is this the question?
LHopital?
can you help me
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fk, wrogn one
use simple algebra in the beginning in order to use L Hopital, and then be a bit careful with the derivatives. next once its in proper form you can substitute x for 2
will do
what are you doin' in the 2 step
multiplying 2x and square root of x
i don't understand
@native gull Has your question been resolved?
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me gots a question
if i wanted to turn a number from one base to another with a matrix
what could it look like
say I wanted to input a number in base 10 and get out a number in base two or something
i'm not aware that that's something possible to do by matrix multiplication
yeah
usually base conversion is done by taking the quotient and remainder a bunch of times
i was pondering how to solve a problem
it was around the lines of having a special base that is based on a function of n
and you could only multiply each place by one or zero
and i was trying to see if you can represent any number using that base
whatever
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Why is abs necessary for the ln x^2 + 25 term? Isn't x^2 + 25 always positive?
(given x in R)
The absolute value is not necessary for ln(x^2 + 5)
(also I already caught the mistake don't worry. I just don't have the corrected answer as a screenshot)
If you have $\int \frac 1u \dd{u}$, you can simplify to $\ln(u)$ if $u > 0$
King Leo
So for functions that are always positive, abs isn't necessary for ln?
Thanks!
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Can someone please help me on this question:
I know BD = 6
and EC=28
and I think triangle ADE is an isosceles triangle
and EC is the base of the quadrilateral BCDE, same as AE is the base of triangle ADE
idk what to do next
<@&286206848099549185>
height of triangle ADE is square root of {312}
area is $14\sqrt {312}$
RamenNoodleMan21
how am i supposed to calculate the area of shape BCED
<@&286206848099549185>
i was thinking you could simplify the quadrilateral into simpler shapes
helllp
it;s my last question please help
nevermind i just solved it
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Did you finish it?
It'd be something like:
[ADE]/[ABC] = (AD•AE)/(AB•AC)
So [ADE]/[BCED] = (14•19)/(25•42 - 14•19) = 19/(75 - 19) = 19/56
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status
i dont know what that means
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
3
!show
Show your work, and if possible, explain where you are stuck.
Can you show your work?
e^ax shouldn't change.
The coefficient comes down, but the exponent does not change.
so it says 5x
e^5x -> 5e^5x -> 25e^5x -> ...
actually how do i know when to stop if they both just continue going forever
So this integral is interesting because it is cyclical.
e^x doesn't change however the trig function cycles back to itself after four steps.
And the only difference will be the coefficient.
So you will get a multiple of the original integral.
okay that makes sense
do you mean like this?
One moment, I'll show you.
Doh, made a mistake.
The fourth term is the same as the original integral with only a difference in the coefficient.
Although I suppose you could do the same with the second iteration. 🤔
okay ya i see that its the same
and that is what signals me that i can stop and have the answer
it says that this is still wrong
Try simplifying
i dont know what that would change?
One moment, let me make an easier example.
So note that I went through two iterations of the DI method. You can write the third line as an integral which happens to be the same as the original integral except that it is negative.
okay so for my question would i just multiply by 2401/125 in stead of dividing by 2?
On the third iteration of the DI method, you would make the fourth line into an integral which is similar to the original integral with only a difference of a coefficient.
ugg im so confused
Ok, let me expand it then.
sorry i dont know why this isnt clicking i feel like it souldnt be this hard for me to understand
wait why does the last box get two lines to it
I chose to stop there because if you move horizontally across, you are making an integral.
And that integral at that iteration of the DI method happens to be a similar to the original integral with only a difference of a coefficient, -125/343.
I suppose its one of those things you have to go through the proof of integration by parts to understand why that is the case.
The DI method is just integration by parts in a tabular form afterall.
okay so you make an integral on the last step, why?
ya but the examples we did all went to 0 and thats how i knew when to stop
which i guess is why he gave us a hw question like this to practice but it still sucks
Because for this integral, both parts will continue on forever if you choose to keep going on. We rely on the fact that on the fourth iteration, it happens to repeat so to speak.
e^5x will be just a difference of a coefficient. sin(7x) will just alternate between +- cos(7x) and +-sin(7x).
But on that third iteration, it makes an integral which is just a difference of a coefficient, -C * I.
where the "I" is what the integral of the original function would be?
Yes.
okay cool
And because it is just -c I, you can add it to the left-hand side.
And to solve for I, you can just divide both sides by 468/343.
where did 468 come from?
oh got it
also why can u turn both integrals into "I" when one is sin and the other is cos
okay so it should be 625/2401e^5xsin7x
I think I got that right now. 🥴
As you can see, even when you "know" what you're doing you can still make mistakes. 😛
Although now that I think about it, you can stop at the second iteration. 😛
omg your going to make me cry
hahah your all good
🥹 its okay
But you see how it is cyclical and the original integral reappears?
ya
,w int exp(5x)sin(7x)
I swear to god constants are my immortal enemy.
is that one just simplified or is there something wrong in my work?
Wolfram's answer is just simplified.
okay sick i was really scared that there was another mistake and i actually would have cried this time
This is really a unique case with e^x and a cosine or sine function that is cyclical.
I don't think there are any other examples in which this will occur, but I'm probably mistaken.
Oh, you'll probably see this on a test.
Just know that if you see e^ax * cos(x) or e^ax *sin(x), you'll want to use this.
Better than 0%.
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Hi guys
Hm?
@wraith hinge Has your question been resolved?
你好
@wraith hinge
What do you want to ask cuh
@wraith hinge this is the place to ask
...
nah we all hate math :)
sorry
no please be honset, I really want to learn from you guys if this is teh case
Is English your first language
uhh yes, please don't be mean I am just asking
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Okay Thanks, I will be right back
- can’t do math, don’t love math, only monkey
So I've got this question, and I am getting the answer as 90degrees, can anyone verify it?
Area = (pi)r^2, circumference = 2pi(r)
Personally I’d solve for radius then use either area or circumference to find the angle
I gues its about the sector of the circle, right? so like the area will be: theta/360 * pi*r^2 and perimeter of the sector will be: theta/360 *2 * pi * r + 2r. Isn't that so?
,rccw
yep
Yes.
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uhhh you guys get the question?
Although I do not know about that +2r part.
Yes.
see the kength of the arc has the formula: theta/360 * 2 * pi * r, cool
and when we need to find the total perimeter of the sector
then we need to add the extra two radii of the sector
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making the perimeter of the sector theta/360 * 2 * pi * r +2r
am I not right?
I’m confused 🤔
wait a second
No need for +2r,
need
2pi(r) = circumference, theta/360 equals percentage of circle
Unless I’m misunderstanding something
the sector also has its "legs" 
I like this method, the theta/360 factors out and you get this system of equations
The perimeter of a sector is the length of the boundary of the sector of a circle. This boundary includes the length of two radii and the arc that forms the particular sector.
the red?
2/360 = 1/180
You’re right, my bad, completely forgot about the legs
Mu bad 🙏🙏🙏
Okay.
Yea it's just a simultaneous equation
So now we have a system of equations, in terms of theta and r.
can you checkout my solution?
also when I found the value of beta, then the radius or the circle was coming to be 6.5, and when solving the equation using the radius the value of theta wasn't matching the value of any of the options given in the options, so I took radius to be 7cm
pleade help guys
<@&286206848099549185>
????
There doesn’t seem to be a mistake, I don’t have a pen or paper with me right now, so I’m not 100% sure
What angle did you get, you can just plug back in to do a quick check
I think there should be two solutions because it’s a quadratic, one small circle with large angle and one big circle with small angle.
yes this is a quadratic equation
and
I am getting radius = 6.5 for the second value of the equation
but when substituing this value in the equation the answer doens't match with any of the options given in the question
so taking r = 7, we get theta = 90degrees
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It's for calculating the number of spectral lines during transition from $n_2^{\text{th}}$ to $n_1^{\text{th}}$ orbit.
If I need to go from $n_2=4$ to $n_1=1$, total number of transitions would be$\$
$4\to3:4\to2:4\to1\3\to2:3\to1\2\to1\\$
So, the formula would be $\binom{n_2-n_1+1}{2}$. But I don't understand how. I came up with an alternate solution
Number of spectral lines = $\sum_{k=0}^{n_2}{(n_2-n_1-k)}\\$
But the first one looks much simpler to implement.
GoldBarley
How do you get to the first formula?
@midnight vessel Has your question been resolved?
because there's one transition for each pair of orbits
n2-n1+1 is the number of orbits from n1 to n2
Oh, and the 2 represents the transition from x->y?
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What have you tried
i dont where to start
Do you understand what the question is asking
yes
Yea so I’ll just say it here so we’re on the same page it’s asking you at what time t is the distance from M to N the smallest
Try to make a function that is equal to the length between M and N
i know
Like for a given t what is the length between M and N
Hmm
Okay so ur struggling with making that function I see
Use the cosine law
lol
idk
same
And I’ll check
lol
my answer match the provided answer
Gg
thank u 2
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Help.
The coefficient of x^(-10)?
binomial theorem, yeah
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I must have a fundamental misunderstanding of cylindrical shells because I keep getting things wrong. Bounds are $$ y=\sqrt{x}+2 $$, y = 2, x = 4. Revolve around x axis. Inverse of the function is (y-2)^2, which should be the height, bounds are 2 and 4. Since there is no offset, radius should just be y. Integrate with respect to y.
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Can you show your work
$$ \pi\int_{0}^{4}\left(\left(\sqrt{x}+2\right)^{2}-4\ \right)dx $$ this I believe should be correct and it evaluates to about 92.
Fragment
this doesn't look like shell method
I don't have my phone with me right now, but I am pretty sure I am not making an algebra error here. y - 2 = sqrtx, (y - 2)^2 = x
It's not, it's the washer method.
ok I see
I set up another method to compare.
The bounds I have are correct, correct variable to integrate with respect to as well.
well that's your region basically
yes
your outer radius should be what
oh nvm
you set it up
ok but what does the solution say?
I do not have a solution sheet, I just know that it is not correct.
Am I getting the radius wrong?
hmm why not
2pi * int r * h dy should be the form
that's shell method
yes
I was comparing the evaluation yes
but yes I don't know whether I am incorrectly finding h or r
what were your bounds
yes
the bounds aren't relevant to r are they?
so h should be h = (4-(y-2)^2)
and r should be just y
I'm braindead
,w Integrate[2pi * y * (4-(y-2)^2),{y,2,4}]
yep
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Can i get some help with a pattern in my game?
So in my game there are harvesters and planters with areas like this
⬜️⬜️⬜️⬜️⬜️
⬜️⬜️⬜️⬜️⬜️
⬜️⬜️⬛️⬜️⬜️
⬜️⬜️⬜️⬜️⬜️
⬜⬜⬜⬜️⬜️
What would be the most efficient layout of both harvesters and planters
Sorry if this a dumb question
gang what.
well maybe cause we dont have any context??
Clearly it's minesweeper
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Could i have shown this by factoring out the 4 instead? as 4n is always even too?
also could I have done this with a direct proof? Did i need a counterpos
By this i mean a = 2n, then a^2 = (2n)^2 = 4(n^2) which is always even
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can somoneone help me w how to start solving
(asking for total vertical distance)
Assuming t -> infinity?
yes
Ok lets consruct a series
Assume n is the amount of bounces that have passed
$\sum{n=1}^{\infty} (2/3)^n$?
oh shoot
$\sum_{n=1}^{\infty} (2/3)^n$?
King Leo
Yes thats what i meant
,w sum (2/3)^n from n = 0 to 1
You should start at n = 0, because the ball technically falls 18 feet before the first bounce
$\sum_{n=0}^{\infty} 18 \cdot (\frac{2}{3})^n$
alwaysonce
Yes
So do you know how to find where this series converges to?
18 / (1-(2/3)) = 54?
✅
Are you missing a factor of 2 somewhere
?
yay ty
Oh
Where
oops yeah i put it in and 54 is wrong
Oh like bc we have to add it bouncing up and bouncing down
Do u think 2(54) - 18 would cover it
Result:
90
wait also when i do this what should my notation look like
Like is the geometric series formula thing supposed to be s_n = a / (1-r)
i forgot if its s_n or smth else
$\mathrm S_n$ refers to a limited sum
King Leo
You should just use $\mathrm S = \frac{a_k}{1 - r}$
King Leo
$\sum_{n = k}^\infty r^n$ converges to $\mathrm S = \frac{a_k}{1 - r}$
King Leo
@tight wind to help construct the proper sequence, can you find how much the ball has travelled between
[0, 1][1, 2][2, 3][n, n + 1]
assuming the sequence is r^n Is a_k always equal to a_0
You dont know that, because the summation might start at n = 5 or whatever other number
ohh
$\sum_{n = k}^\infty a \cdot r^n$ converges to $\mathrm S = \frac{a_k}{1 - r}$ writingto visualize
alwaysonce
(in this formula, you can technically replace a_k with r^k
Btw a is a sequence, while a_1 is a number
Like isn't a always 18 here
No, $a_0 = 18$
King Leo
18 meters, 18(2/3) + 18(2/3), 12(2/3) + 12(2/3), uhh
Try to separate it differently
What youre doing will be confusing, because from h = 18 to h = 0, the ball technically only performs a half bounce
So i would recommend like this:
Calculate red distance, calculate green distance
Red distance is 30 and green distance is 20
So whats the ratio
Then what is a_2
3:2
In the sequence $a_n = 18 \cdot \qty(\frac 23)^n$, $a_2 = 8$
King Leo
It should be (next distance) / (previous distance)
When ur finding where this series converges to using a_k/(1-r) why am i using 18 as a when 18 is just a_0 and not a_k
What is k here
k is the start of the summation
2/3
$\sum_{n = \textcolor{red}k}^\infty r^n$ converges to $\mathrm S = \frac{a_\textcolor{red}k}{1 - r}$
King Leo
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OHHHHH
If n were to start at 2 here, then to find where it converges would it be 8/(1-(2/3))
✅
umm
is it not 18
im cooked for my test😭
#help-38 message (tell me if you need me to explain further)
So you have:
$$\sum_{n = 0}^\infty 30 \qty(\frac 23)^n$$
King Leo
Can you find what that converges to?
W spelling, but np
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(btw you technically never needed the summation. You could have just use a0 = 30 and r = 2/3 to invoke the S = ... formula)
Oh ok true
This was also right. Just do 2 * 18 (2/3) + 2 * 18(2/3)^2 +...
And factor out a 2
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like i couldve done -18 + 2$\sum_{n=0}^{\infty} 18 \cdot (\frac{2}{3})^n$
alwaysonce
?
,w -18 + \sum_{n = 0}^{\infty} (18 * (2/3)^n)
Ok um
Something messed up
,w -18 + \sum_{n = 1}^{\infty} (18 * (2/3)^n)
nvm
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Earlier when i ddi 2(54) - 18 it worked though
If the answer is 90, how did 2(54) + 2 work
Sry brainfart edited
You need to ask riemann about that 🤷♂️
This is correct
Oh u typed it wrong here
,w -18 + 2 * \sum_{n=0}^{\infty} 18 \cdot (\frac{2}{3})^n
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I need help when explaining how both c angles of the triangle are congruent, what would be the reason but mostly why?
Please don't occupy multiple help channels.
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The box is 48 cm, if the diameter ratio between large and small circle is 2:1, what is the minimum area of the circle indside the box?
π(48 -x)², then find the X vertex
X vertex= 48, then (48-48)²
I sum up all of the area of circle but couldn't get the result
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i did answer the first step of the question which is to get the inverse function but i don't know how to get the domain and range
domain will be x\in R since the denominator will never be 0, range will be y\in [-3,3) since there exist a horizontal asymptote y = 3, and since the numerator can be 3(x^2-1), where x^2-1 always bigger or equal to -1, the lower bound is -3.
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Solve for $x = \frac{a\pi}{b}+k2\pi,k\in\mathbb{Z},\frac{a}{b}$ in its simplest form: $2\sin{x}\sin2x=3-\sqrt{3}\sin{x}$
nhknyugn
!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 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
Step 2
I tried applying some trigonometric formulas but then I got stuck...
My first attempt was to try converting these into a single variable t=sin(x)
$4\sin^2x\sqrt{1-\sin^2x}=3-\sqrt{3}\sin{x}$
nhknyugn
Not that bad to solve
Do I have to check the case if \cos{x} is negative => = \sqrt{1-\sin^2x}?
No i believe
Square both sides, u have a kinda nice quartic
$16\sin^4{x}(1-\sin^2{x})=9-6\sqrt{3}\sin{x}+3\sin^2x$?
nhknyugn
Wait actually nvm
Probably not the right approach then
@wheat stirrup Has your question been resolved?
anyone who can help with a physics problem help 8 pls
@wheat stirrup Has your question been resolved?
I tried that
oh mb
got any ideas?
Nope
write 2sinxsin2x as cosx-cos3x
take the sin term to the LHS
cosx+√3sinx-cos3x = 3
the maximum value of the function on the LHS is 3 and this occurs when cosx+√3sinx = 2 and cos3x = -1 simultaneously
from the first equation you will get the condition x = (6n+1)𝜋/3 and from the second x = (2m+1)𝜋/3
take the intersection and you will be left with the solution set x = (6m+1)𝜋/3, m∈ℤ
@wheat stirrup
I don't understand this part. How did you conclude cosx+√3sinx = 2 and cos3x = -1
the maximum value of cos+√3sinx = 2
and the minimum value of cos3x = -1
only for these values would the equality hold
you have to find all the points of maxima of the function on the left
cause it varies from [-3,3] and the RHS is 3
global maxima that is
not local
Take m=0 => x = 60°
I plugged it into original equation, the equality doesn't holds
ye the solution set is correct
oh, in desmos the graph was showing an error idk y
hen i equated them
btw which app/website is it?
desmos
huh
Is it a coincidence that the RHS is the maximum value of the LHS?
its most prob intentional
Yeah I guess so
cause otherwise it would be much harder to solve
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np
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wtf
so this is my question
and what i have so far
i just need help on what i need to do next
Ur doing it wrong
is my work right so far
how
Ur working out is not right
whats wrong?
P x a x D
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Help I dont know how they got this
You look at the right matrix and start 1 maps to 2
then you look in the left matrix for the 2, 2 maps to 4
so the result is 1 maps to 4
and you do that each time
2 maps to 4 on the right
on the left 4 maps to 1
so 2 maps to 1 is the result
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Translate:
-
Given: A...D₁ is a cube with an edge length equal to √72 cm.
Find: the distance between the lines AA₁ and BD₁ -
Given: ABCD is a rectangle, MB ⊥ (ABCD), AB = 60, BC = 80.
Find: the distance between the lines MB and AC
I need help not with solving the tasks themselves, but with drawing for these tasks
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Yes
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how would one decompose $\frac{x^4+1}{x^3+2x^2+x}$
haveaniceday12
haveaniceday12
yes, but we've only been given one example and we didn't use that
but i skipped lecture so maybe i missed that
how would one use polynomial long division for this
u are close
tbh polynomial division is the easiest way
i know that the general formula is some function + remainder/original denom
yes
multiply x by entire divisor
substract the original dividend
then repeat the process
then what's the problem you are facing?
in this case, i don't know what will be what when i am done
explain
like when i get my final result, what will that actually be in terms of the decomposition
well acc i think i know
but what will be the remainder
this is what we were told
so using polynomial long division, i guess that the thing we get after dividing is q(x)
whats the question?
but what is ax^2 + bx + c in this case
^
the question is right in front of you idk what i can say
where
