#help-17
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$t^3 = 3t$ and $t^2 = 3$ are not equivalent because going from the first one to the second one means dividing both sides by $t$ which is not possible when $t=0$
artemetra
because we can't divide by zero
yes
so substituting back we get that log(x) = 0, log(x) = sqrt(3), log(x) = -sqrt(3)
for which value of x is log(x) zero?
0?
yes
so x=1 is one of your solutions
ohh
in your textbook, is $\log(x) = \log_e(x) = \ln(x)$ or $\log(x)=\log_{10}(x)$?
artemetra
$\log(x)=\log{10}(x)$
𓉸ྀི
so, if we have $\log_{10}(x) = \sqrt{3}$\
how do we solve for x?
artemetra
divide by log10?
yes
artemetra
by same logic $10^{-\sqrt{3}}$ is also a solution
artemetra
so your final answers are $x=1,10^{\sqrt{3}},10^{-\sqrt{3}}$
artemetra
no problem
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hey guys i have a math question that isnt really a question,im buying a supplement and doing the general bulk calculation and as of rn i got a whole graph plotted and have been looking at the costs and im stuck between buying 60 or 120,anyone down to help?
ill give you the values
x=y
x=number of capsules
y=price per capsule
30=0.32
60=0.27
90=0.27
120=0.23
150=0.23
180=0.21
210=0.21
240=0.21
270=0.21
300=0.21
I suppose it depends on how much you'll need
hmm i mean i wanna do 120 or 60
because based on da math they da best
@upper haven Has your question been resolved?
Why?
60 has one of the highest price per unit
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hi
i dont understand
where did they get the extra 1 from
inside the [ ] brackets
MethIsAlwaysRight
now its just factoring (1/8)^x out
chillies
how?
Not sure how clear this is
But it's basically just this and some mucking about with rules of exponents
$(\frac{1}{8})^{-2}=((\frac{1}{8})^{-1}))^{2}=(\frac{1}{8})^2$
DootDooter
i should learn the rules of exponents then
ok thx
i see
so whenever theres a negative exponent thats even
it swaps to a positive
or does it matter if its odd or even
as long as its negative its always swaps to a positive?
but how is 1/8^2 of 64
wouldnt it just be some super small decimal
So the key idea is that an exponent of -1 flips a number, so a^(-1) is 1/a
It doesn't matter if the exponent is even or odd
so
if its always negative
it always swaps to a positive
so just think as if negative exponents dont exist only positive ones
Mmm I wouldn't think like that exactly
What I think when I see a number to a negative power like a^(-n) is that the negative sign can be replaced if I swap out a for its reciprocal.
Well you don't have to do it.
You can just leave the negative exponent sometimes. So the wording "always" here is a little too strong imo.
If you remember this rule though it always gives you a way to swap out negative exponents for positive ones tho
It's not 64 you left off the - sign on the 2
Just takes a bit of practice. Thankfully these rules won't change much as you do more math.
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when i multiply the bottom by 3 both x and y will =0 when i combine them
how do i solve it if both =0
my math is a bit rusty when it comes to systems but
couldn't you just multiply the bottom equation by -3
and cancel out the -15y and 15y
yeah thats what i meant
but then -12 will cancle 12
so i will have two things that =0
so idk what you do in this case
i've tinkered around a bit
the answer is Ø
no solutions exist
whatever you try they all just cancel out
does the answer have to be word for word or is it checked manually by the teacher
wait is there infinate solutions or not a solution
there isnt any solutions
wait is there infinite solutions or not a solution
if i am correct no solutions
if the lines are on top of each other there would be infinite though?
since they are constantly touching each other
im not sure though
we might want someone else to verify
these are not the same value afaik
if you multiply the bottom one by 3
it becomes
12x+15y=-6
they're not the same
yeah im correct
they're parallel
checked on desmos
i checked on desmos too
and i only see one line
doesnt that mean one is under the other
zoom in
how do i show my work for this one
can you submit images?
or does it have to be just a written thing
and is it a type of test where you have to enter an exact answer or you can enter something and it is checked later by the teacher
just written im not allowed a graphing calc for this assignment
well i am
its just
you cant use it as evidence
ah
well its checked by the computer first
then the teacher verifies
that the computer marked it right
so normaly i get like a 50%
then my teacher marks it and its a 90
or above
well i mean you could write that the unknowns cancel each other out if the second one is multiplied by -3 or if both are multiplied by a common factor ( one of the signs flipped of course due to being forced to use the method of elimination)
i dont know if the computer will like that though
if you could send an image into that prompt this proof would be much easier
its only like a few lines of actual math
i guess i would just submit this
since it is checked by a teacher too
ok
can i just write 0x+0y=-9 on my paper then write that the lines will be parrel without the same y intercept
or how do i explain i know they will be parrelel
without using a graping calc
hm
when the 2nd unknowns are multiplied by -3 the yielded answer is smaller than the 1st one
so i guess because the 2nd is not equivalent to the 1st
the yielded graphs are parallel and as such they have no meeting point
their slope ( i think thats what its called i am from croatia my english is not top notch when it comes to math jargon lol)
is the same
can i write "since both 0 and y =0, and they do not = 0 it means that they are on the same slope with a different y-intercept, this means they are parallel while not overlapping"
since both x and y equal to 0, and the 2 equations arent equivalent to each other, it means that they are on the same slope with a different y-intercept, which means that they are parallel yet never overlap nor meet
that should be good?
think so
did everything i do so far here look corrct?
just want to make sure i didnt make mistakes before i do the big work
yeah it is correct
how do i do elimination
so i need to make s
33
by multiplying the first one by 11
and the 2nd one by 3
-3
or -11 the first one its optional
one of them has to be negative
basically when you do that and cancel the unknown all you're doing is adding the equations together
ok, but is that the correct thing to do?
yeah when you're asked to do elimination
there is multiple methods of solving but they want explicitly elimination
ok
sorry my power went out so i might be a bit slow now
im using my hotspopto
hotspot*
hopefully my laptop doesn't die
@wild meteor Has your question been resolved?
<@&286206848099549185>
i did something wrong
but what
i need help
wait no i didnt
.close
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What are the next 5 terms in the sequence 1,1,2,3,5,8,13?
I can’t c the pattern
Fibonacci sequence
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Is this correct so far and how would I do the top two questions?
,rccw
that doesnt look like proper sets
and they would be wrong even if they were
how did you come to your domain and range exactly?
we'll start there
i created a set for the domain based off of each x value for the points, then i did the same for the Y
that would work if the function were just those points
but it isnt
i can see that f has point at -6, -2.1, 4,5, etc
isnt that what each point is?
no
youve tried to say the domain is only those points
but f is defined outside of them also
i dont understand
like you can say the domain of 1/x is (-inf,0) U (0, inf)
that encloses all values 1/x can take as inputs
what youve done is like saying the domain of it is (-3, -2, -1, 1, 2 ,3) just because its defined for those points
which isnt the true domain
okay, how do i do this correctly then?
do you believe f is undefined for any x value?
im not sure i understand
what do you think the domain of a function is?
a set of x values for each point on the graph
not really no
the domain of a function is the set of values a function can take as an argument
more practically its the set of all values that if you input into the function youll get a defined value as the output
alright
from the graph of f, do you think it has any points where it doesnt have a defined value?
i mean anything outside of the line
im not sure what your question means
you're making this seem incredibly complicated
from what i've been told and taught i take the set of x and put that down to get the domain
but what you wrote isnt the complete set of x is what im saying to you
what about 4.1? 4.1111111111111111? 4.24224434?
those are all in the domain
(negative infinity, infinity)
so then when would it be numbers instead of infinity
you mean if the domain was literally just something like {1,2,3}?
yes
no
if the domain was (-2,5) that could still be a line
its just not discrete values
so i can have a line or wave and have it still not be infinity?
how do the graph the points then
it could be any shape, as long as an x doesnt map to two values (for a function)
thats function specific
what do you think it is
(negative infinity, 5)
(negative infinity, 5]
what about the increasing and decreasing intervals?
you seem to have the idea of what they mean, wanna have another go?
negative infinity to 5, then 1 to four
is that increasing then decreasing?
no just the increasing points
not quite
first off, -inf to 5 contains 1 to 4
and there is decreasing between -inf and 5
eg at -2
but there are two rises
there are, but your bounds are wrong
how so?
5
5 is on the far right
you dont write y values as your intervals
its in terms of x
rewrite them
so i can see what you really meant
ah so negative infinity to -4 then 1 to 5
much better
for decreasing -4 to 1 then 5 to negative infinity
(-4, 1) (negative infinity, 5)
those should be the easiest honestly
you just find the y value for each input
youve already done that
oh 0 and 3?
yup, that simple
thanks! thats not bad at all
no worries
are you aware thats a parabola?
nope lol
,w graph x^2
that shape is a parabola
how did you do that so fast
magic
anywho, all quadratics have that shape, or a flipped one
you can identify the transformations and then just move the x^2 graph about to match it
do you know where the vertex is?
if youre opting to sub in specific values in a table, youll want to center around that
no i dont, i was asking how to graph it
im not sure about the other stuff but i feel graphing it is a good place to start
y=(x-1)^2+2 is a parabola in vertex form
y=a(x-h)^2+k which means the vertex is (h,k)
this is the shape
you can get some good values if you want to by doing this
im not sure i understand
which bit?
thats what ive been telling you though
theres literally no more i can give you on how to graph it
its all there
apart from finding roots and y intercept
thats it
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: Bingo is a game in which each player has a square card with k
rows (horizontal) and k columns (vertical), where k^2 distinct numbers taken from
set {1, 2, 3, . . . , N}. Numbers are drawn one by one and players must mark on the
card the drawn numbers. We have two game types, A and B.
Mode B: Here, whoever completes a line on the card wins the game. From this
At this point, let's consider this type of game.
(a) Two cards are said to be similar if the two cards always win the game together,
that is: for any line on the first card there is a line on the second card that
have exactly the same numbers. Once a card is fixed, calculate the number of cards
similar to her.
(b) You want to make bingo so that each person plays with a single card and not
there are 2 similar cards. What is the largest number of people who can participate?
!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
how did you get (k!)^2 for a)? just interested in the reasoning
also are both columns and rows considered lines?
or only rows
seems to be correct
ok ok, thank you so much
just wanna be sure
mm
you reasoned as k! ways to permute rows and k! ways to permute columns?
yes
because
i'll take an easy example and see if there's something wrong or now
take grid
1 2 3
4 5 6
7 8 9
permute rows 1,2
4 5 6
1 2 3
7 8 9
permute columns 1 and 2
5 4 6
2 1 3
8 7 9
ok no maybe there's nothing
yes, its correct, not?
yes, but we need to argue a bit about why
so two cards are similar if there's a finite amount of row permutations and column permutations that link them
rows: you can permute k rows of the card in k! ways
permuting columns: for each permutation of the rows, you can permute the k columns in k! ways
And that simplifies down to 1 row permutation and 1 column permutation
because
a row permutation followed by column permutation
is the same as column permutation followed by row permutation
it gives the same result
yes
so if you had
(row permutation) then (column permutation) then (row permutation) then (column permutation)
you are allowed to regroup the row permutations together, same for column
because it's commutative
(only between a row permutation and a column permutation, since two row permutations won't commute)
so we regroup them into
(1 big row permutation) then (1 big column permutation)
which leads to what we did here
k! possible row permutations
k! possible column permutations
wait I realized
so it gives the samething, no? but with a complex reasoning
there's another operation we can do
transposing
ie
1 2
3 4
can become
1 3
2 4
and I'm not sure if you can get that with row/column permutations
since the diagonal needs to stay in place
so 2 (k!)^2
but at the same time it doesn't make sense, because when you only have 1 number it should be only one possibility
but here we're saying it's 2
ok in the meantime I'll show what happens for small values of k
k=1, one way
k=2
1 2
3 4
1 3
2 4
yeah 8 ways for k=2
so
is 2(k!)^2?
to be honest
I understood your reasoning, but I don't understand why mine is wrong
two cards are similar if they share the same lines
however we interpreted that as "they have the same rows and they have the same columns"
k=0 makes very little sense so avoid it
k=1 would just give 1
I'm making a python script to compute the number of ways with other values of k so if you have some time to wait
@vast shale Has your question been resolved?
sorry for the wait @vast shale the code is working
for k=2, k=3 the value 2(k!)^2 is correct
The code has been running for 2 minutes computing for the case k = 4
so, its not correct for k=4?
no it's just that my code is so inefficient that it takes too long 😢
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This one seems really intuitive, but I cannot prove it.
Let A in R^n be an open set, with n >= 2. Given a in R^n - A, the set A U {a} is open if, and only if, a is an isolated point in the boundary of A. Equivalently: there exists a ball B = B(a,r) such B-{a} is contained in A.
Well, what I really want to use is the fact that A is in R^n with n>= 2. We can find a sequence of points in the interior of R^n - A if such ball does not exists, but that doesn't seem to help me getting more points in the boundary.
wait if a is on the boundary of A then this should be false no?
a is on the boundary of A
No, consider an ball with a single point in the middle missing
Let a be that point in the middle
yeah this is was my drawing as well
the thing is this is not true for n = 1.
A = (-inf,a)
yea but as its on the boundary if A, part of the ball would be outside A no?
No, read my example again
Anyways
Equivalently: there exists a ball B = B(a,r) such that B-{a} is contained in A
This is pretty much the definition of open right
Like, you already know that property holds for every point in A
if it holds for a as well then A U {a} is open
no, but a is not in A
Yes I know
Which one is harder?
ohh yea i got it sorry
np
if a is an isolated point from the boundary of A, then AU{a} is open
well we already know if we choose a point in A then it'll have a neighborhood that's in A and thus in A U {a}
all we need to do is check that that property holds for a as well
yes
That's the property I quoted here
From your initial message you seem to know that that is equivalent to a being isolated
hmmm not really, for me isolated means that there exists a ball such that a is the only point from its set in that ball. But in this case we could "hipothetically" cointain points from A and int(Rn - A)
as in the case of (-inf,a)
yea so all points in the ball excluding a would be in A right
Oh, it sounded like you knew it was equivalent
no no, the questions says it's equivalent. if you prove this proposition the if and only if one follows and vice versa
sorry bad english i'm translating from my portuguese book
oh ok
no worries
What you want to do is imagine a neighborhood of an isolated point on the boundary @zinc heron
Or rather an open ball of radius r
For the sake of contradiction assume every such ball contains points not in A.
Because it's on the boundary, it also clearly contains points in A.
Remove a from the ball, the resulting space is still path connected. Find a path from the inside of A to the outside of A, this path must contain a boundary point
Ah well you can construct the specific path
i'll take a closer look into it. thanks
Np
yeah there's a theorem here that may help
well thank you very much
sometimes books do that lol
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can someone please explain to me why the eigen values are -3 and 1
shouldnt it be 3 and negative 1?
-1+-2
just the last line
sqrt(1+3) is 2
shouldnt the eigan thing factor to -3 +1
sorry
the line before that then
how did he get to that line
(x+3)(x-1) thats fine sure
nw
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$\frac{(|z|-1)(1+iz)}{z-\frac1{\bar{z}}} = i$
$(|z|-1)(1+iz)=\frac{i\bar{z}}{|z|^2}$
not sure what to do next
solve for z
yeah, thats how i got the |z|^2
looks messy, but sure let me try
,,
\begin{cases}
|z|-b|z|-1+b=\frac{b}{|z|^2}\
a|z|-a=\frac{a}{|z|^2}
\end{cases}
you mean $(|z|-1)(1+iz)=iz(1-\frac{1}{|z|^2})$
rafilou2003
what is |z|
absolute value of z...?
yes, but it's value?
i dont think i want to solve a system of equations with square roots
wait a minute till i try to solve it
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i think this has no solutions
if you want to find a solution, first note that |z| is different from 1, then write z = f(|z|)
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hi
hi
HI How to get domain and range of (x+4)/(x-3) and all asympotes
for domain, what values can x not be
0
if x=0
we have -4/3
so x can be 0
but x cant be 3
since we will have 7/0
which is undefned
oh thanks
and as x approaches infinity, the +4 and -3 becomes insignificant so the only thing that would matter would be x/x = 1
so the horizontal asymptote would be y = 1
oh thanks I understand now
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hello
I tried to calculate the area under a x² curve
y = x²
x² is rotating
so that means
what interval and axis
V = pi * Integral ( y² ) dx
post the full question
are you trying to calculate the volume when rotating around the y axis
"Show the formula for calculating the volume under a x² rotating curve from point a to b"
I said area my bad
the hell does that mean
exactly what it says
define a rotating curve
a formula for calculating the volume under a x² curve rotating from a to b
assume x² is like a cup
its a rotating
function
and x² is like the radius of the cup
you're using the wrong terms but i get it
ok then what's the formula
are you rotating around the x or the y axis?
V = pi * Integral (y²)dx = pi * integral(x^4)dx
x axis
man I think thats my problem
should be around y axis no
anyways
the solution would be
if it is the formula is different
you're messing up the formula
pi*b^5/5-pi x a^5/5
you use that formula when rotating you don't get "holes"
you do get holes here
wait let's clarify
assuming rotation around x-axis, sure that works
my problem is that
then it's correct
ok then the formula is correct
well
negative how?
for the volume
from a to b means you have to do b-a
wait
setting the integral up like this
a <= b
sad
im sorry guys
im really sorry
didnt intend to waste time
it should always be positive lol
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no problem
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Helo
I play a minecraft World and im trying to transform a rectangular area to a ellipse.
Length of the rectangle is 168 and width is 129
I don't know how to calculate an ellipse in which the rectangle fits perfectly.
If possible give me an easy explanation how I can calculate that.
Thank you guys for your efforts
,,a \cdot b \cdot \pi = 168 \cdot129
coolseph (𝔸dωn𝓲²s)
there are many possiblities to construct an ellipse that has the same area as that rectangle
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How can I show the monotony intervals of a function?
find its critical points
how ?
,rcw
critical points are:
- points where the derivative is equal to 0
- points where the derivative is not defined
- points where the function is not defined or discontinuous
what are you trying to find, exactly?
i need to determin the intervals of monotony
okay. in this one it looks like you've found those?
you can see that on (-oo, 0) it's decreasing, for example
so I just need to make the graf, noting more ?
i suppose that depends on the format you're expected to put it in
is good, a friend texted me and said i need to '' matematicaly write'' the graf too
thx for the help
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i Know this is not a true question. But i want any good source that covers all lines integrals topic and explain like I am five. I did not find any good ones
I am more into videos
khan academy ?
does khan academy covers everything in calclus 2 level ?
like green's theorem and all stuff?
it has multivar calc i think
okay thanks
@polar vine Has your question been resolved?
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I am kinda lost right now haha, but how can I convert this integral in terms of polar coordinates?
$$\iiint_V 1 : \dd V = \int_0^9 \int_{-3}^3 \int_{-\sqrt{9-x^2}}^{\sqrt{9-x^2}} \dd y \dd x \dd z $$
I tried to parameterize the volume $$\vec{v}(x,y,z) = \begin{pmatrix} x \ y \ z \end{pmatrix} = \begin{pmatrix} x \ y \ 9-x^2-y^2 \end{pmatrix} $$ into
$$\vec{x}(\theta,r) = \begin{pmatrix} r\cos\theta \ r\sin\theta \ 9-r^2\cos^2\theta-r^2\sin^2\theta \end{pmatrix} = \begin{pmatrix} r\cos\theta \ r\sin\theta \ 9-r^2 \end{pmatrix} \quad r\in [0,3], : \theta \in [0,2\pi]$$
coolseph (𝔸dωn𝓲²s)
how u gonna access the other dimension with only one varying angle? :D
introduce another free angle but consider the bounds on it, or rather the angle you currently have written
ok let it be phi
uhm
do i need spherical coordinates?
yeah... but I was just gonna ask im slightly confused by the original integral written
is it a volume of sphere question?
$$\vec{x}(\theta,\varphi,r) = \begin{pmatrix} r\cos\theta\cos\varphi \ r\sin\theta\cos\varphi \ (9-r^2)\cos\varphi \end{pmatrix} \quad r\in [0,3], : \theta \in [0,2\pi]$$
coolseph (𝔸dωn𝓲²s)
haha it was a task of calculating the flux
Flux of $S={\vec{x}\in \mathbb{R}^3 : : : z = 9-x^2-y^2, : z \geq 0 }$ with $\vec{\textbf{F}} = \begin{pmatrix} -x \ 2xz \ 2z+1 \end{pmatrix}\$
coolseph (𝔸dωn𝓲²s)
and I used gaussian theorem
But I was rather interested on how to do it with other coordinates
really?
I just cant set up the integral bounds haha
It's basically a circle
and then I am integrating over height
so maybe I need a second radius, or like 2nd angle
,,\int_0^9 \int_0^{2\pi} \int_0^3 r : \dd r \dd \theta \dd z
coolseph (𝔸dωn𝓲²s)
you did it using divergence theorem?
yea
\begin{align*}
\iint_S \vec{\textbf{F}} \circ \vec{\textbf{N}} + \iint_{S'} \vec{\textbf{F}} \circ \vec{\textbf{N}}
&= \iiint_V \vec{\grad} \circ \vec{\textbf{F}} : \dd V \
\end{align*}
where $S'={\vec{x}\in \mathbb{R}^3 : : : x^2+y^2 \leq 9, : z = 0 }$
coolseph (𝔸dωn𝓲²s)
you can split it up into arbitrary sections
with some limitations on things
you can't have jumpy around bits
you can split something like a sphere into two halves
but you can't take some crazy subset of the sphere
anyway
SO HE was right
yea
cross prduct
and you wanna find a good way to write down dA
of the tangent vectors
cuz you have $\iint \vec{F} \cdot \hat{n} dA$
Katharine
yea
oh i forgor the differentials
and then you find dA
there's no triple integral
as you're doing it directly
you integrate over the surface
triple is when you use divergence theorem
and calculate over the volume contained in the closed surface
i say that but you can use triple integrals but i wouldn't as that requires the integration limits to be funky
yes i wanted this 🙏🏻 sorry
you want to use divergence theorem?
yes
i was interested if can somehow switch the coordinates
\begin{align*}
\iint_S \vec{\textbf{F}} \circ \vec{\textbf{N}} : \dd S + \iint_{S'} \vec{\textbf{F}} \circ \vec{\textbf{N}} : \dd S'
&= \iiint_V \vec{\grad} \circ \vec{\textbf{F}} : \dd V \
&= \iiint_V (-1+0+2) \dd V \
&= \iiint_V \dd V \
&= \int_0^9 \int_{-3}^3 \int_{-\sqrt{9-x^2}}^{\sqrt{9-x^2}} \dd y \dd x \dd z \
&= \int_0^9 \int_{-3}^3 2\int_{0}^{\sqrt{9-x^2}} \dd y \dd x \dd z \
&= \int_0^9 2\int_{0}^3 2\sqrt{9-x^2} : \dd x \dd z \
&= \cancel{4}\int_0^9 \underbrace{\int_{0}^3 \sqrt{9-x^2} : \dd x}_{= \frac{1}{\cancel{4}}\cdot \pi \cdot 3^2} : \dd z \
&= \int_0^9 9\pi : \dd z \
&= 81\pi
\end{align*}
coolseph (𝔸dωn𝓲²s)
I did it this way
but was wondering
if I could somehow switch from dydxdz to polar coordinates or something like that
you could use cylindrical
polar but also z
dz
dr dtheta dz
if you want to find the volume version
yea i did that above
.
but is that all?
like couldnt I also somehow switch dz
i mean you could
but it would make it worse
because the shape you want is not symmetric in any way along z
it is constantly different as you go along the z axis
if you wanna calculate the integral directly i think something like dtheta dz
or dtheta dr
and then have z be a function of r
or vice versa
that will give you dA
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The first question
ah geez
@vast shale Has your question been resolved?
Will changing it from $\int$ t^m/(2+t^m) dt to $\int$ 1/(2t^{-m}+ 1) dt be useful in this case
you have to ❌ or it will lock
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What
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How do I find the axis of symmetry using either the table or graph?
to find it using the table you find two x values with the same output (y value) and average them
put x= to it and that's the axis
Hmm okay
Is it viable if I use the vertex formula?
Okay I solved it thx for info!!
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usually x(t) and y(t)
it makes more sense if you look at one with arrows
maybe something like this
this used to be and still kind of is a decent site for these
you should try playing around
click on the upper left, and select system
but this?
well, it goes in that direction laterally
but also dy/dt at that point is going to impact the a;rrow
yeah iknow
so if dy/dt is 0 at that point
and dx/dt is negative
then it will point directly left
yes
because only the sign of x' is going to contribute to its leftness or rightness
theres a nullcline here that is very helpful
a nullcline is a curve along which at least one of x' or y' is equivalently 0
y=2?
why is it helpful?
there vectors for dy/dx
well, i dont know if vectors is the most helpful word
but why would a nuciline be usefull?
so a purple line is maybe better thought of as a trajectory
if you pick an initial point, so ( x(0), y(0) ) along a purple line
it will move along that purple line, it will stay on it
like the blue and red lines here
so try to interpret what is going on at y=2
lets say we pick an initial point ( x(0), y(0) ) = (0,2)
what happens?
y will not change for all x @pallid zenith
yea, i think that at least within the range of the plot, it looks like y will stay about the same
can you express this mathematically?
maybe an equation
maybe some kind of equation that expresses the change of y 
yea, maybe more specifically, if y=2, then y'=0
we dont know anything about it, really
but why is it useful for this plot
well, at least not from this observation
yh for the ranges of the plot atleast
they give you some candidates
right
so the usual strategy is one of two
either you try to plot each, and see if they match
trial-and-error
or you try to identify features you know must exist
and rule some out
process-of-elimination
were doing the second
we know that y'=0 where y=2
(at least within the range of the plot, yadda)
so, can you identify any systems where this isnt the case?
then, we can reject them as candidates
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you got it? 
ah ok
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<@&286206848099549185>
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What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
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2
What does this mean? Is it a command of some sort?
ok so it looks like it's oriented clockwise
May you please help me?
I'm trying the problem rn
Okay
what part did you get stuck on
Okay just a sec I'll show you my work...
Sorry I have so many papers idk where I put my work. It may take me some time.
Okay I think I'll just change it to 1 and start all over again.
I used exactly this it did not work out.
I don
So basically, the point is that instead of evaluating the line integral directly, we can instead calculate the double integral, which is often easier
oh okay
thanks!
How would you set it up?
So here $L=e^{-x}+y^2$ and $M=e^{-y}+x^2$
Ari
and these are just taken from the vector field given
So $M_y - L_x = 2x - 2y$. So that's what goes inside the double integral.
Ari
@uncut tendon were you able to get this far