#help-39
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help
i need help solving these please
what have you tried
haven't really tried it yet, just been stuck and figured I could use some help lol
alr
you can factor the first one
that will cancel some stuff out
actually you dont even need to do that
plug in 0 for x and tell me what you get
yea
so as the x approaches zero, the result of the function is equal to 5
now how about the next one
what happens when you plug in 0
would this be proper form for the first question ?
yup
I think
on the 2nd to last line do you still have a 4x?
can't really tell what that is
yes 4x
other than that it's fine
but there is no more x
you're taking x to 0
so x becomes 0
should it be (0^2 - 4) (0-5) then ?
NahhFam
ohhh okok I see
could I try the other 2 and then can you check over it to see if i got it right?
a friend suggested it lol so idk
should I have used something else
in your opinion should I or should I not be using it for grade 12 calculus and vectors
it depends
have you learned L'Hopitals rule yet?
if you have then that's fine
but if you haven't I'd tried other ways
no we haven't learned it yet, I think we will next week
then yea don't use it
I'd multiply by ((3+x)(3-x))/((3+x)(3-x))
same as multiplying by 1
and distribute to see where it leads you
NahhFam
Compile Error! Click the
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(You may edit your message to recompile.)
$\frac{\frac{1}{(3+x)} - \frac{1}{(3-x)}} x \frac{(3+x)(3-x)}{(3+x)(3-x)}$
you get the idea
is it cool if you can show me ur answer and work for number 3, I didnt really know how to do it
Im gonna figure this out while you figure that out
yea lol
I will once you solve part b using this method
ok I will try it
there
okay
NahhFam
ok i think i got it
yea
ayy okk
is for proper or is smth missing
okok
lol
I don't think the algebra is proper
meh close enough lol
it's w/e
so the last one
you need to multiply the top and bottom by the conjugate of $\sqrt{x+1} - 2$
NahhFam
NahhFam
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I do not understand b)
Probs got a wrong too but I can fix it myself
@fringe ice Has your question been resolved?
In which direction is the bucket accelerating
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$\frac{dx}{x(y^2 - z^2)} = \frac{dy}{y(z^2 + x^2)} = \frac{dz}{z(x^2 + y^2)}$
Leahalcyona
Find the first integrals
(maybe method of finding integrable combinations (properties of proportions))
@alpine imp Has your question been resolved?
<@&286206848099549185>
@alpine imp Has your question been resolved?
Of which equation exactly here
for example you can rewrite:
Leahalcyona
$dx = x(y^2 - z^2)dt, \\
dy = y(z^2 + x^2)dt, \\
dz = z(x^2 + y^2)dt$
@alpine imp Has your question been resolved?
@alpine imp Has your question been resolved?
@alpine imp Has your question been resolved?
no idea whats the question here @alpine imp
@alpine imp Has your question been resolved?
@alpine imp what have you tried so far?
i tried and found some already, just wait cuz i can't send it rn, I'll be free in a few hours btw
what's this supposed to be used for?
obv its a dif eq
looks like triality
in metric spaces
or something
hmm
<@&268886789983436800>
post your question in an unoccupied help channel
@alpine imp Has your question been resolved?
Wdym find the first integrals?
Ive never heard of that
Wat class is this? @alpine imp
Hint: You can use Newton's second law of motion on both a and b
you will also need to do a bit of algebra here too
This question has gone completely off the rails, but if you multiply the equations by x, y, z respectively, you get ydy-zdz = xdx which you can integrate immediately.
Read my original question again and think about it
Maybe you should show some work rather than tell the person responding to you to think about it. This is your homework, not mine.
As I understand a first integral, e.g., a non-constant differentiable function that is locally constant on a solution to the PDE, that step leads you there.
Let me simplify things for you. Let's start by introducing the following:
(am not sure how true the statement about f_i \neq 0 is, tho)
@humble lintel
Are you listening?
And this property is invertible btw
Now, we can use the method of integrable combinations
to find the first integrals
According to the given condition, the system is implicitly defined by a symmetric form:
Leahalcyona
Leahalcyona
(have omitted some trivial explanatory steps)
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look at the concept of the first integral in ode systems context please
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Can somebody please help me with this
I've used IBP twice but I dont think I've done it correctly
- you forgot the bounds
- no need for a second IBP
Um
But
So I use the bounds for xsinx - cosx
$\int_0^\pi x\cos(x)\dd x=[x\sin(x)]_0^\pi-\int_0^\pi\sin(x)\dd x$
Bonk
What's the integral of sinx?
You don't need 2nd IBP to evaluate the integral of sinx
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why can we assume tension is proportional to (y_n+1 - y_n)/h
@dire basin Has your question been resolved?
small angle approx?
@dire basin Has your question been resolved?
isnt that like sin(theta) is approximately theta
is that what they're doing here
if ur evaluating the vertical component it'd be Tsin(theta)
i was thinking between the string segment and the horizontal
vertical component of the tension is what causes the restoring force yeah
thats T sin theta
oh right cause sin is approximately tan im dumb lmfao
actually why can we even assume the angle is small
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how would I go about solving this?
so to work out where are are starting from: do you know what it means to be/not be O(f(n))?
Yes, it means g(n) grows at most as fast as f(n) for large n
have you considered using an approximation for N! to help you get started?
𝓡𝓞𝓚𝓔𝓣𝓣𝓞─୨ৎ─❥ ♡ <𝟹❤
(to e^x but you dont need to use that bit)
That is more elegant that what i as going to suggest
So it approaches 0 which then means that that the C does not exist right
which means its not O(2^n)
okay thanks for the help
no prob
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I think the answer are d,b,c can someone double check for me
yes
It's correct?
@woven oyster Has your question been resolved?
yes
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The answer for A says the direction of average acceleration is South 5 degrees West
But Im not sure how is that possible if you see the diagram
I've drawn vector v1 and v2, and the definition of average acceleration is change in v/change in t
change in v should be vector subtract of v2-v1
and ive drawn the subtraction on the right, and the result vector can't be South 5 degrees West, more like South X degrees North
How is my thinking or direction wrong?
Also the question assumes we start on the 1st quadrant at 0 degrees and travel clockwise
Also for context, I've calculated the degrees travelled after 40 seconds is 10.19 degrees clockwise
where is the drone after 40s?
it is travelled 10.19 degrees from 0 degree at quadrant 1
uhh is it similar to the diagram you drew
ok so how did you get this
Ok so the vector subtract applies to the velocity vector, which are perpendicular to the acceleartion vectors, so the vectors outside of the circle. I put them tail to tail, v1 and v2
ok i see what you're saying, you're doing v2 - v1 and getting a vector pointing up and to the right
Please show the original problem, exactly as it was stated to you, with the entire original context. A picture or screenshot is best. If the original problem is not in English, then post it anyway! The additional context might still be helpful. Do your best to provide a translation.
im pretty sure it should be v1-v2
the question assumes we start on the 1st quadrant at 0 degrees and travel clockwise
this is def not true, our teacher taught us v2-v1
bc it's change in velocity so u use the later velocity
to subtract the initial
well then you labeled the vectors wrong
you labeled later v1 and initial v2 yeah
No i think ur corresponding those to the acceleartion vectors
its not really about the name of the vector, its about final - initial
the V1 is the straight line going to south
do you at least agree with this
yes
ok so whats the final and whats the initial here
and what do you get when you do the subtraction
are you 100% sure the rotation is clockwise?
yes
our teacher sent us this
ehh, maybe idk
its def 10.19
my answer matches the answer key value
just the direction is diff
my acceleration magnitude is correct
@feral sedge is the angle wrong moni
idk it should be north
East North?
no
?
west north
np
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Cos-1(5/8)=51.32 degrees
The answer is wrong right?
why are all these answers off, C is 200/6.2=32.26
answer key seems wrong again?
@trail swallow Has your question been resolved?
<@&286206848099549185>
I agree with your answers
Just worked them out
The answer key is blatantly wrong, for part A even the units are wrong
It answers a different question than what was asked
alright thanks
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a
both
when i tried this and its incorrect?
you forgot to multiply the last part by 1/2
@ivory shadow Has your question been resolved?
show your work for this question
i got it
thank you
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Im not sure if the answer is +inf or -inf
what is the limit of the factor on the left?
What do you mean?
what is the limit of x^2+1
Can you guide me step by step?
$\lim_{x \to \infty} (x^2+1)$
LocalLunatic
do you know how to do this?
where did the /x^2 come from
we are not doing limit of a fraction
i suggest going over your notes to see when you need to divide by x to the highest power for a limit
https://www.youtube.com/watch?v=NmLljBAg82o&themeRefresh=1 look through some examples here
This calculus video tutorial explains how to find the limit at infinity. It covers polynomial functions and rational functions. The limit approaches zero if the function is heavy at the bottom or if the degree of the denominator exceeds that of the numerator. The limit approaches a constant value if the degree of the numerator and the denomin...
i cant explain a full lesson to you unprepared
I know how to do it, maybe we have different ways
What could be your answer?
I'm just checking
the answer to $\lim_{x \to \infty} (x^2+1)$ is $\infty$
LocalLunatic
Where's the other binomial?
LocalLunatic
then you multiply them together
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i know that colA is an output thingy and nul A is an input thing, so p has something to do with the desired column length and q has something to do with the desired row length? How do i find these values
how long is your column vectors
how many components does it have
3
so its a subspace of R how many?
well your col space is a subspace of Rq
and we know that your column space has 3 components
so q is?
3????????????????????????????????????????????????
yes
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i think my y bounds are wrong but im not sure why?
@hearty flame Has your question been resolved?
@hearty flame Has your question been resolved?
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,rotate
Couldn't find a role matching tate!
,rccw
,rotate
Thanks
I used differentiation thingy and I don't know what to do now
I'm just stuck in general
Which exercise are you solving, 3?
@fair eagle Has your question been resolved?
What have you tried so far?
I did a now just finding b
Given a remainder of -4 when divided by (x+1), what equation in terms of a,b,c, and e can you get?
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s
nino
oh it worked
testing the latex
but anyways im 90% sure my proof is correct
its a physics problem but im purely concerned with math
i kinda don't get how you got there
yeah i was kinda unsure
so basically i think dx/dt is
[
\frac{dx}{dt} = v \cos\theta \quad \text{(constant, no acceleration)}.
]
nino
and vertical dy/dt is v sin theta - gt
i mean taking the derivative of x(t) = cos , t gives that right?
the derivatives and how you simplified it seems fine to me
i am questioning the substitution if done properly
or did you consider gt-vsinθ-vsinθ = u-vsinθ
hm idk looking at it it seems wrong
,w Integrate[Sqrt[v^2-2 *g * t * v * sin(theta)+g^2t^2],t]
ugly
I will try to rewrite it with less constant chaos
A quadratic under a square root, your best guess is to complete the square and apply a trig sub, I believe
is that easier than the u-sub here?
Let me see
This integral is geometrically speaking like the area under a half circle
yeah that makes sense
v^2+gt(...)
Sorry I'll brb
Ok I see NOW how you got there
Seems it will simplify nicely due to the trig identity sin^2+cos^2=1
I would check with wolfram calculator
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Nice chart
idk just keep perpendicular axes theorem in mind and you're fine
Depends on your prof, thats probably more than enough. I have never bothered to learn anything other than 2 and 3, and I still sometimes mix them up.
You can actually derive them from the general formula
calculus... 😔
can't escape it
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Can an orthogonal set be linearly dependent?
Consider S = {(0, 0), (1, 0)}
They are orthogonal as <(0,0), (1,0)> = 0 (using euclidean inner product)
But clearly they are linearly dependent
orthogonal nonzero vectors are linearly independent
but any set that includes the zero vector is linearly dependent
Okay, so suppose we get the question "Are the vectors in any orthogonal set always linearly independent", would the correct option be no because the zero vector basically
yes that would be correct unless they explicitly or implicitly said nonzero (e.g. if they said "orthonormal" that would implicitly mean nonzero)
yw
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The sum of the second and fourth terms of an increasing geometric progression is 45, and their product is 324. Determine the first term of this progression.
it's just a
quadratic problem
a+d+a+3d=45
and
(a+d)(a+3d)=324
you get two solutions from this
i'm kinda
blind
sorry it's still the same
ar+ar^3=45
lol
a^2r^4=324
and a^2 r^4 = 324
it's still a quadratic problem
thank you
did you solve it?
@midnight flicker Has your question been resolved?
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My friend said use substitution
is the top the original
Yes
(just a bit difficult to read the denominator in the original)
Cosx-(5-4sinx)
Denominator
I was thinking
Taking x=pi/2 first
We get A = 1
If we don't open brackets
If we do we can't take anything common even if we make both sine or cosine
So by doing like this I got a=1
B=-4
$$ \int \frac{1}{\cos x (5 - 4 \sin x)} $$
OR
$$ \int \frac{1}{\cos x - (5 - 4 \sin x)} $$
StrangeQuarkAL
1st
bruh
And have to partially split it
the subtraction threw me off man 🙏
but yes u sub would work
How
nvm
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I think I’m tweaking how do I find the point of intersection between two lines again….
set them equal to each other
Do I solve for x?
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hello, could someone help me on this problem. this lesson is called completing the square and my calcualtions arent the same as my teacher provided answer key. can someone help?
what have you tried
alright so this is my work
and this is the teacher ansswer sheet
You have a mistake.
your teacher is wrong
wdym the teacher is wrong
you started well last step is wrong tho
This is correct answer.
i just realized the extra plus bruh
you can't just add a +4
you need to subtract also one, else you lose equality
hm
like you did
then (x^2-4x+4) completes to (x-2)^2
how this now
This is right.
yeah i just re did my calculations
your teacher still forgot to write +16
why would there be + 16
Hi. Imagine you're adding 0.
You transform that 0 into +16-16=0.
To not modify the original expression.
oh i see if my modified term b is negative i must add a positive equivalent to cancel it out?
English isn't my native idiom... What?
when you add (b/2)² then you also need to subtract it
ok yeah thats essentially what I said
and vice versa I assume
x²-8x+16-20 not just x²-8x-20
you know something ive notice is that the term I use to factor is almost always just half of B
alright so heres what I got so far based off that
the C term is always positive so switch it with +16
wdym C term, 4 is the C term
16 is the modified B term
ok lets call it differently
X term
the one inside or outside the parenthesies
\begin{gather*}
y = (x^2-\underline{8}x+\underline{16})-16-4
\end{gather*}
oh yeah these exist
Magic.
no because there is no positive 16 in the first place
I think we just wildly misunderstood it, she went straight for the answer and didnt bother writing the + 16 and the middle equasion
AldaraLaRana
basically yea, but again leaving out the +16 is still mathematically wrong
and you would and should get points off
so dont follow her
Yup, is it.
bim.
huh
Then you solve for:
7x=2xy.
Got 7/2.
But that's only y, we want y^2.
We square up the 7/2.
49/4.
what does the square have to do with anything
Ah...
we didnt do ones without C
That because we are completing the square, so we want to our final answer to be in the form (x+y)^2.
idk how she wants us to magically know it
hold up im gonna call the other guy over too rq
@rough forge
I'm bad at explaining, so yeah, it will be helpful.
why are you pulling my cape
i need thoust wisdom
That's me so fr.
I have two questions without C and she didnt teach us how to do them
Oh... I have and idea on how to explain this, c = 0, solve in the same way.
,, y = x^2 + 7x + 0.
AldaraLaRana
oh these are even simpler
you need to factor right?
yeah
can you see a common factor
X i guess
I'm blind...
this might be dumb but how would I factor 7x
just x
ok
Oh
complete the square
not factoring
same thing
add and substract (7/2)²
your c is just 0 yea
so this was the right thinking
then whats 12.25
is that the modified B term
,calc (7/2)^2
Result:
12.25
ok hold please
yes
hows this
you mean factor?
no recognize the square
still wonder how she got that
hmm
oh well
I think im good but ill keep the channel open for 15 mins in case i get confused on something
yes this is wrong
(x-2)²-1 = x²-4x+4-1 = x²-4x+3
thats what happens when you just add terms
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I have an elementary set theory question regarding a definition I can’t understand,
The definition is that of the product of a family of sets
The latter being defined (for a family Xi (i in I) as
{ F | F defined in I and for all i within I F(i) is in Xi }
Where the F’s are functional graphs
To exemplify this I used this simple family indexed by {0,1}
Thus this gives me the set of graphs with said property (written at the bottom)
However I don’t see how this expression is equivalent to the basic two set Cartesian product which is {(3,5),(3,6),(4,5),(4,6)} (we should only be accounting for the second coordinates of the graphs)
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<@&286206848099549185>
i don't get how this definition is supposed to work
what does "F is defined in I" mean and where exactly does F come from, and what does F(i) mean
And I wish someone pinged <@&268886789983436800> on you - oh wait...
now as it stands it seems like I is both index set for (X)i and domain for F's, if that's the case then what set do functions F come from
F’s go from I to the unions of Xi’s with the condition F(i) belongs to Xi for all i
okay, i think i get it
so in my understanding the definitions don't really produce the same objects
but objects produced by both definitions are isomorphic (so there is bijection between them), which allows us to treat them as the same object
specifically, we can associate each function graph F from (1...n) to some set X with n-tuple of elements from X
@frosty hatch does that make sense?
@frosty hatch Has your question been resolved?
That does make a lot of sense considering the graph definition comes with that of a function -from the product to the set of sets- of a "projection" which for a certain i gives: F —> F(i)
I suppose that’s the bijection (if we extend all of the i projections to a common function over the whole thing) which then allows us to simply consider the graphs as their second coordinates
Thank you
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so by a previous theorem it suffices to show that f(V) is open in Y for every open set V in X
so what i thought about is the following: Let $V\subset X$ be open in $X$, then $\forall p\in V\ \exists\delta>0\ \text{such that}\ x\in X\ \text{and}\ d_X(x,p)<\delta\implies x\in V$. now $f:X\mapsto Y$ is continuous on $X$ and so $f$ is continuous on $V$. Thus $\forall\varepsilon >0\ \exists\delta>0\ \text{such that}\ d_X(x,p)<\delta\implies d_Y(f(x),f(p))<\varepsilon$ and $x\in V$ so that $f(x)\in f(V)$. Thus $f(V)$ is open in $Y$
d_X and d_Y denote the metrics on X and Y respectively
is this correct? or is it missing something
well i think it has a problem
since i didnt use the compactness of X
I don’t get how this proves that f(V) is open
Also as a quick side question, do you know what a homeomorphism is?
i am not sure too maybe i thought that this proves that f(V) is open while it is not. But i thought that this proves f(V) is open since i just found a neighborhood of f(p) which is a subset of f(V) for every open set V no ?
so i proved that for any p in V , there is a neighborhood of p in V such that for each x in V, f(x) in f(V) where these f(x) form a neighborhood of f(p), didnt I?
no
i wont encounter this here since i am studying real analysis not point set topology and the author didnt mention homeomorphisms in the chapter that he presented the concepts needed from point set topology in
I think you just showed that all points at a max distance delta from p are mapped to points at a max distance epsilon away from f(p)
Which is directly from the definition of continuity
yes but arent all points f(x) elements of f(V)?
Yes
if so , then doesnt that form a neighborhood of f(p) in f(V) ?
which means that f(V) is open no ?
because this is the case for any p in V
But I don’t think that necessarily means that ALL points in the neighbourhood of f(p) are image points of f
Or at least I don’t think you have proven that
You showed all image points under f of x at a distance less than epsilon from p is mapped to the ball of radius epsilon from f(p), you need to kind of show the converse, that all points in the ball of radius epsilon from f(p) are image points of f restricted to V
yes you are right , thats what i should do because it is directly applying the definition of continuity to f^(-1)(x) on f(V)
so i need to prove that if $p\in V$ then $\forall\varepsilon>0\ \exists\delta>0\ \text{such that}\ \ d_Y(y,f(p))<\varepsilon\implies d_X(x,p)<\delta\ \forall y\in Y\ \text{and}\ x\in V$
right?
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need help
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@jade moss figured it out?
This is what I was about to suggest, so excellent work
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The length hanging down as a function of time and the speed when the chain loses contact with the table are derived using Newton's second law and energy conservation.
Length as a function of time:
The differential equation governing the motion is ( y''(t) = \frac{g}{\ell} y(t) ). Solving this with initial conditions ( y(0) = y_0 ) and ( y'(0) = 0 ) gives:
[
y(t) = y_0 \cosh\left( \sqrt{\frac{g}{\ell}} , t \right)
]
Speed when losing contact:
Using energy conservation, the speed ( v ) when ( y = \ell ) is:
[
v = \sqrt{ \frac{g(\ell^2 - y_0^2)}{\ell} }
]
Final Answer:
The length hanging down is (\boxed{y(t) = y_0 \cosh\left( \sqrt{\dfrac{g}{\ell}} , t \right)}) and the speed when contact is lost is (\boxed{v = \sqrt{\dfrac{g(\ell^2 - y_0^2)}{\ell}}}).
nino
To verify the solution, we systematically apply Newton's second law and energy conservation:
1. Deriving ( y(t) ) via Newton’s Second Law
Force Analysis:
- The gravitational force on the hanging portion at time ( t ):
[
F = \mu y(t) g
] - Total mass of the chain: ( \mu \ell ).
- Newton’s second law (( F = ma )):
[
\mu y(t) g = \mu \ell \cdot y''(t) \implies y''(t) = \frac{g}{\ell} y(t)
]
Solving the Differential Equation:
- The equation ( y''(t) = \frac{g}{\ell} y(t) ) is a linear ODE. Its general solution is:
[
y(t) = A \cosh\left( \sqrt{\frac{g}{\ell}} t \right) + B \sinh\left( \sqrt{\frac{g}{\ell}} t \right)
]
Applying Initial Conditions:
- At ( t = 0 ), ( y(0) = y_0 ):
[
y_0 = A \cosh(0) + B \sinh(0) \implies A = y_0
] - Differentiate ( y(t) ):
[
y'(t) = A \sqrt{\frac{g}{\ell}} \sinh\left( \sqrt{\frac{g}{\ell}} t \right) + B \sqrt{\frac{g}{\ell}} \cosh\left( \sqrt{\frac{g}{\ell}} t \right)
] - At ( t = 0 ), ( y'(0) = 0 ):
[
0 = B \sqrt{\frac{g}{\ell}} \implies B = 0
]
Final Expression for ( y(t) ):
[
y(t) = y_0 \cosh\left( \sqrt{\frac{g}{\ell}} t \right)
]
2. Speed When the Chain Loses Contact (( y = \ell )) via Energy Conservation
Initial Energy:
- Initial potential energy (center of mass of hanging chain):
[
U_{\text{initial}} = -\frac{1}{2} \mu g y_0^2
] - Initial kinetic energy: ( 0 ).
Final Energy:
- Final potential energy (entire chain hanging):
[
U_{\text{final}} = -\frac{1}{2} \mu g \ell^2
] - Final kinetic energy:
[
KE = \frac{1}{2} \mu \ell v^2
]
Energy Conservation:
[
U_{\text{initial}} + KE_{\text{initial}} = U_{\text{final}} + KE_{\text{final}}
]
[
-\frac{1}{2} \mu g y_0^2 = -\frac{1}{2} \mu g \ell^2 + \frac{1}{2} \mu \ell v^2
]
Solving for ( v ):
[
\frac{1}{2} \mu \ell v^2 = \frac{1}{2} \mu g (\ell^2 - y_0^2) \implies v^2 = \frac{g(\ell^2 - y_0^2)}{\ell}
]
[
v = \sqrt{\frac{g(\ell^2 - y_0^2)}{\ell}}
]
3. Dimensional and Physical Consistency
- Hyperbolic Function: The argument ( \sqrt{\frac{g}{\ell}} t ) is dimensionless, as required.
- Velocity: Units of ( \sqrt{\frac{g(\ell^2 - y_0^2)}{\ell}} ) simplify to ( \sqrt{g \ell} ), which is dimensionally correct.
- Edge Cases:
- If ( y_0 \to \ell ), ( v \to 0 ) (no motion if chain is already fully hanging).
- If ( y_0 = 0 ), ( v = \sqrt{g \ell} ), matching free-fall intuition.
Final Answers:
[
\boxed{y(t) = y_0 \cosh\left( \sqrt{\dfrac{g}{\ell}} , t \right)}
]
[
\boxed{v = \sqrt{\dfrac{g(\ell^2 - y_0^2)}{\ell}}}
]
not sure if this is right
nino
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how can i solve for x and y in y+1=x^4 and (x+1)^3 = y
that looks like a rather ugly 4th degree equation. where did you get it?
says who?
the teacher
i think you do something with the logs
and dont rewrite them as equations
also a classmate found a loophole in the question
do anyone knows hyperbola
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!da2a
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and what would that be
i thought the paper was calculator
looks like -1 is a sol?
non coalcaultor*
these reduce to an ugly cubic without a rational root
but its calculator
yeah so that lets you knock the degree down to 3
x^3-2x^2-x-2=0
good luck solving that lol
google cardanos method
ok and what school do you think teaches that
that looks painful
thats why i said google
don't try to be a smartass in help channels @autumn trellis
its okkk im pretty sure i was just supposed to plot the two equations
that ain't it chief
Can somebody explain b?
This is the answer to a) btw if it has to be used in b)
NVM I GOT IT
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Prove/Disprove: if $a_n$ converges to a finite limit then $\lim_{n \to \infty}(\frac{a_n}{n})^n=0 \
Proof: $a_n$ converges therefore $a_n$ is bounded. let's look at the expression $(\frac{a_n}{n})$. $\lim_{n \to \infty} \frac{a_n}{n} = \lim_{n \to \infty} \frac{1}{n} \cdot a_n = 0$ (a series converging to zero multiplied by a bounded series, converges to zero) using the definition of limit let's choose $\epsilon = 1$ there exists N such that for all $n \geq N$ we get $|\frac{a_n}{n}| < 1$ therefore $|\frac{a_n}{n}|^n$ is a geometric series with |r|<1 therefore $\lim_{n \to \infty}(\frac{a_n}{n})^n = 0$
prograce
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@rapid wagon Has your question been resolved?
its not a geometric series
there is no common ratio
the a_n/n could be changing quite "randomly"
you want to get rid of the a_n. you cant control it
you already know its bounded
call the bound a
work with that
Epsilon delta
@rapid wagon Has your question been resolved?
|a_n|<=a, so therefore |a_n/n|<= ?
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we don't have the answers for this
but can i know what the new height is for this question?
i got 0.78 and idk why but im quite certain that im wrong ://
show your work
so for a
the volume is like 6.48
so the missing part is 23.52
then
let the ratio be v/3
where v is the new radius
1/3 * (v/3)^3 * 3^2 * 10 = 23.52
then i got like v = 2.77
then the new height = 0.779
How do you calculate the volume without the radius of the liquid's surface?
all your calculations should be exact in terms of pi
nah
but pi cancels out on both sides
set ratio
cuz its similar triangles shit
how did you get 6.48 for the volume
but how did you get it
cuz ratios
the height ratio
6/10
so the radius is in this ratio
so radius is 1.8
pir^2h
Just forget that
ok, so you should be writing the pi for those values
in terms of pi doesn't mean you don't write pi
ye for part a it is
but for part b it isn't
and i just cancelled out pi
volume would be 6.48pi,
and missing/empty part would be 23.52pi
i don't understand your work after that,
ye
ok so
uhh
cuz the ratio of radii
is equal to ratio of heights
so i let the radii of the empty part of the cone in part b be v
then
1/3 * pi * (v/3)^3 * 3^2 * 10 = 23.52
pi
,calc 3/5 * cbrt(2) * 7 ^(2/3)
Result:
2.7662617752351
that'll be the length of the red line
apply the ratio between h and r to get the height
and subtract that from 10
mhm
seems like that was what you did,
your work just wasn't clear
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help
