#help-27
1 messages Ā· Page 302 of 1
if its just dust, couldn't you just, like, wipe it off and be all good?
if you remove the embers from the building, the light they gave off is not left behind
yes
if you spill it on the floor, you wipe it off and you;re good
then you have to bury the rug
we can't stop it, we wait until it burns out
@dry oak oh also UV from the sun is the same thing right?
so that's confusing
yeaaa idk about the sun, but ive heard that it damages skin cells and can cause cancer, i tan anyway :P
oh ok microwave is the opposite end, i thought it's between uv and gamma
makes sense then
so the left side cooks you a lot, but doesn't touch dna
and the right side is opposite
i guess it's like that
dang so higher frequency is basically more dangerous
which one here is radiation?
They're all radiation
all of this is radiation, starting from UV it's "dangerous"
starting from X-Ray it's nuclear
A bit wrong
All rays can be generated without nuclear
Photon is a bit special
They carry energy using a packet
Before Enstein
huh? dont we get xray in hospitals š
Photoelectric effect is unexplainable
People thought photon energy derive from intensity
But its frequency
Its a long paper
@dry oakalso nuclear bombs do all of this, and the goal is to make the left side radiation, one that cooks
the "dangerous" side is pointless
just can;t avoid it
Nope
Pretty sure a bunker build underground from steel (for support) and lead (for shielding) can stop the gamma ray
water can stop radiation too right? hence the blue light effect
Not that effective agaisnt gamma
You want dense material like lead and tungsten or depleted uranium
can't avoid producing it i meant
i started doubting that it's insignificant in total energy
but seems true, it's less than a third at least
The X-rays you get in a hospital are called hard X-rays, and they're more on the right of that image, so they're more energetic. Because of how energetic they are, X-rays can give you increased risk for cancer, if they are absorbed by DNA and cause mutations. But for medical use, X-rays are generally very controlled and you are only exposed to them for a very short amount of time. Generally, if you are in need of getting an X-ray, the benefits of getting the X-ray and being able to get a medical diagnosis and treatment outweigh the potential risks. X-rays generally come from electrons, not the nucleus of an atom. This happens when an electron jumps down from a higher energy level to a lower one, releasing the energy in the form of a photon. The nucleus of an atom generally emits gamma rays, which are even more energetic.
For the discovery of X rays, the physicist Rƶntgen was awarded the first Nobel Prize in Physics
But yes, everything from radio waves to microwaves to the light you see to X-rays operates under the same principle. The only difference is the frequency of the radiation, which changes how much energy each photon has. This form of radiation is called "electromagnetic" radiation because it travels as a wave through the electromagnetic field.
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could someone verify (numerically) if $$\psi \left(\frac{2n+1}{4} \right) - \psi \left(\frac{2n+3}{4} \right) = \Phi \left(-1, 1 \frac{2n+3}{4} \right)$$? Here $\psi$ is the digamma function and $\Phi$ is the lerch transcendant
rak³en
Okay nvm seems false
yeah def false
chat could yall help me with this
I used the fact $\psi(z) = \gamma + \int_0^1 \frac{1-t^z}{1-t}dt$
rak³en
so basically that means $$\psi \left(\frac{2n+1}{4} \right) - \psi \left(\frac{2n+3}{4} \right) = \int_{0}^{1} \frac{ t^{\frac{2n+3}{4}} - t^{\frac{2n+1}{4}} }{1-t} dt$
At n = 1, LHS is pi - 4, rhs is 
rak³en
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yes i confirmed that with wolfram just now
hence this
wait actually nvm got my blunder
thx
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Hey lol
Tf isn't the imaging going
is this correct?
also assume first line is 100% correct
also i think the mistake is when i switch the sum and the integral
(done by fubinis theorem, but i never check the conditions xd)
pretty sure its simply convergence though, which it should
HMMMMMMMMMMMM
OKAY so I am getting
rak³en
Where in reality it is
rak³en
umm
hmmm did you miis the change from 1/2 to 1/4?
you're geting: 1/2 of left sde = Right side tho
oh yeah lol right i missed wayy too much
1 sec lemme re latex
got $\psi \left( \frac{2n+3}{4} \right) - \psi \left( \frac{2n+1}{4} \right) = 2\Phi \left(-1,1, \frac{2n+5}{2} \right)$, but supposed to be $\psi \left( \frac{2n+3}{4} \right) - \psi \left( \frac{2n+1}{4} \right) = 2\Phi \left(-1,1, \frac{2n+1}{2} \right)$
rak³en
And I can't spot the mistake š
the mistake shouldnt be after this page, because all I did was simply write it as a lerch transcendant on the next page
also I gtg for a bath so yall if someone finds the mistake pls do share it
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$\psi(z) = - \gamma + \int_0^1 \left(\frac{1-t^{z-1}}{1-t}\right) \dd t$
is the right formula. what you're using has {z} in place of {z - 1} in the integral @finite briar
that is shifting your Lerch transcendent's a by 2
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Hi, when doing data normalization, how do we choose between max-normalization or min-max normalization?
OMFG TYSM!
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I drew a lil diagram sorry its not the best
The equation of the circle is (x+1)^2 + (y+2)^2 = 9
a few different approaches exist
We dont have either the x or y coordinate of the tangent
I would recommend subbing in y = ax + b, expanding and rearranging to get a quadratic in x
then you can use the fact you need discriminant = b^2 - 4ac = 0
since you only want 1 x-value, for 1 intersection -> tangent
and also -2 = a * 11 + b, so you have -2 - 11a = b
so you really just have a quadratic in x, and a as some unknown constant
1 moment im rereading a few times to try and understand
Ok I think I get it all except this bit
Where do these numbers come from?
you sub (x, y) = (11, -2) into y = ax + b
Ahh
Alright I will try
(x + 1)^2 + (y + 2)^2 = 9
(x + 1)^2 + ((mx + c) + 2)^2 = 9
x^2 + 2x + 1 + (mx + c + 2)^2 - 9 = 0
(mx + c + 2)^2 is really really messy šµāš«
( ... = 0 at the end there)
Yh it'll be a little
Treat it as ( [mx] + [c + 2] )^2
(because it will sort out your x-powers for you)
This -2 and 11
up to you, so you'd get mx + c + 2 = mx - 2 - 11m + 2
yeah actually that's easier now
Ok thank god š
x^2 + 2x + 1 + (mx + c + 2)^2 - 9 = 0
x^2 + 2x + 1 + (mx - 2 - 11m + 2)^2 - 9 = 0
x^2 + 2x + 1 + (mx - 11m)^2 - 9 = 0
x^2 + 2x - 8 + (m^2)(x^2) - 22xm^2 + 121m^2 = 0
Actually im not sure
What is a, b and c in b^2 -4ac
Do I get a = 1 from x^2? Or is it a = m^2 because of the (m^2)(x^2)?
Im stuck on this part
try collecting the terms of x^2, the terms of x, and the constant terms (including 121m^2)
also you mean -22xm^2
What do you mean sry
I think thats the part im stuck on
Like is x^2 the only x^2 term or is (m^2)(x^2) also an x^2 term
you can group x^2 + m^2 x^2 = (1 + m^2) x^2
Ah ok
Ahhh I see what I need to do
x^2 + 2x - 8 + (m^2)(x^2) - 22xm^2 + 121m^2 = 0
(1 + m^2) x^2 + (2 - 22m^2) x + (-8 + 121m^2)
So a = (1 + m^2)
b = (2 - 22m^2)
c = (-8 + 121m^2)
b^2 - 4ac = 0
(2 - 22m^2)^2 - 4(1 + m^2)(-8 + 121m^2) = 0
4 - 88m^2 + (- 4 - 4m^2)(-8 + 121m^2) = 0
4 - 88u + (- 4 - 4u)(-8 + 121u) = 0
4 - 88u - 484u^2 - 452u + 32 = 0
-484u^2 -540u + 36 = 0
-4(121u^2 + 135u - 9) = 0
yeah hold on
(2 - 22m^2)^2 = 4 - 88m^2 + (-22m^2)^2
= 4 - 88u + 484u^2
so you actually just get 4 - 88u - 452u + 32 = 0, everything else is right
4 - 88u + 484u^2 - 452u + 32 = 0
no, you are missing +484u^2
so if you add it back you get 4 - 88u - 484u^2 - 452u + 32 + 484u^2 = 0
Ohhh
I thought you meant my sign was wrong haha
Okok I see
4 - 88u - 484u^2 - 452u + 32 + 484u^2 = 0
36 - 540u = 0
540u = 36
u = 36/540
u = 1/15
m^2 = 1/15
m = +-sqrt(1/15)
Those are the slopes of the tangents
yeah
you just need one of the tangents so you can choose say m = sqrt(1/15)
also remember from the very beginning, -2 - 11m = c
For a min i forgot what the original question was š
So many u's and m^2's
but ok
-2 - 11m = c
-2 - 11(sqrt(1/15)) = c
Cant simplify that
yeah just leave it then
you mean, x/sqrt(15) - 11sqrt(1/15) - 2
Ah yeye
wait can I ask you, how far are you in trig?
could you simplify something like tan(arcsin(u)) using a right triangle?
š¤©
I have covered the whole course but I took a looooong break and now I have to relearn / remember everything hehe
I have a quicker way if you know that, cause this question is quite specific
the centre happens to lie on the same horizontal line as (11, -2)
I dont think so...
okay then don't worry about it
Is it an identity of some kind?
yeah, it's actually not that bad
Could you teach me? If you dont mind
if theta = arcsin(u), then sin(theta) = u
so you can let opposite = u and hypotenuse = 1
so adjacent = sqrt(1 - u^2)
and tan(theta) = u/sqrt(1 - u^2)
for this question u happens to be 3/12 = 1/4
tan(theta) = sin(theta)/cos(theta) = y/x
so that gives you the slope of a line
Ok 1 moment I need to reread that a few times to understand
,w 1/sqrt(15)
Ah cool
That is actually a really neat way of doing it
I thiiiiiiiiiink I get it but im gonna do some more examples with this method to make sure I do
yeah then the identity follows if you replace 3 with u, and 12 with 1
so that sin theta = opp/adj = u/1 = u
Ah yeye I think I get it
My brain is fried after this question so Im gonna take a quick break before I try some more examples hehe
But thank you sooooo much for your help
no worries!
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so we got this exercise, dont mind the different language because ill show my solution so that should help
thing is, i came up with a solution, got to the right answer....but the solution has a flaw in it that actually makes me wonder why it works
at the top of the page i put what we know so that its easier to understand
the problem here, is that i amplified with z-|z|
so multiplied and divided
which we dont know if its zero or not
because if it zero, then i couldnt do that
one of the multiple choice actually even sais that z=1 so it was a possibility
anyone got a clue why this works?
if $\overline{z} \neq -|z|$ then $z \neq -|z|$ as well
artemetra
because |z| is real
You have to check, for which z, you have Im(z² + 2z|z|) = 0
it sais that z is complex
so for no z
or wait
idk what you wrote there honestly
but it makes sense that z is different that |z|
since one is complex and one is real
|z| not equal z conjugate implies z is not purely real
or wait
The conditions should be Im(z) = 0 or Re(z) + |z| = 0
No need to over complicate
Since it says w is real, multiply num, denom with (z + |z|)
(z{bar} + |z|)(z + |z|) is now real
So, (z + |z|)² is real
=> z² + 2z|z| is real
Plug z = a + ib, and you have your conditions, 2ab + 2b|z| = 0
So, b = 0 or a + |z| = 0
i dont understand what youre saying by multiply with denom conjugate
like, z conj - |z|?
multiply num, denom with (z + |z|)
how do you know that thats different than 0
huh? what is different than zero
YES
whats the conjugate of a sum
if im(z)=0 doesnt that just mean that z is real?
just hold on until i write it down, i may have some more questions if i dont get something
what do i do now
@slender mirage
basically, multiplying algebraic expressions and expanding
how would you do it otherwise?
It's like I give you (a + b)(b + c)(c + a) and you expand it all the way to get 2abc + ...
=_= I never told you to expand denominator
what are you supposed ot do?
isnt that what you do?
NO, not when it's not required
but you will =_=
we multiplied denominator with its conjugate because
For any complex number w, ww{bar} = |w|² is real
So denominator is real even if you do not multiply and expand
Got it?
NO
=_=
all this time
the denom is (z{bar} + |z|) yes?
i feel violent
no no lmao
good
brother, what do you want me to do
i dont understand
shouldnt i have multiplied how i just did/
sure
denom is (z{bar} + |z|) yes?
damn right
(z + |z|) is its conjugate yes?
hell yea
=_=
so the denom automatically becomes real, yes?
Yes. No?
damn
so we gotta have z² + 2z|z| as real
plug z = a + ib
i thought that if (z+|z|)^2 is real then z+|z| is also real
i need to check this myself
it doesn't mean that 
howd did you get that so easy?
im tempted to just literally see what (a+bi)^2 is
you only need the imaginary part 
and then substitute in z as well
Yes that is what I did 
picked the imaginary part from the expression after substitution
did not -_-
so you would get 2b(a+|z|)=0
Yes lol, solve that equation now
oh yea, thats right
what is |z|
ā
sensational
this was way harder than i thought
which we could've just guessed by putting numbers
thought itd be easy peasy
=_= which part of what I showed you was hard
you sound like u just like gambling, man
none i guess, its just some properties i forgot about
im reminding you that im recapping for an exam rn
no
when you do competitive exams a lot, you need to have a way to quickly deal with stupid problems
so thats why i forgot some things
those problems are called no brainers
damn
unfortunately
there's not many no brainer problem up here
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$(-4)^{73} / 2^{144} - 25^{12} / 5^{23}$ idk how to start
Simon James B
$(-2^2)^{73} / 2^{144} - (5^2)^{12} / 5^{23}$ like this?
Simon James B
but from here i am stuck
Try expanding out the brackets
He doesn't have that though, he's got (-4)^oddnumber
Simplify the right side first before the left. The right side is much easier
.
still confused on what to od
depression
I know! But is this the easiest way? we are supposed to do to the easiest
That is the easiest way
Okay I just re-read
Just simplify it down and the answer will fall out
$-2^{146} / 2^{144} - 5^{60} / 5^{23}$
Simon James B
Just sub in and simplify
but we do not have the same base how do i make 2 negative
-(2^146)=-2x2^145
?
or it does not matter
Sub this
Do you know how to factor?
That's true
$-2^2 -5^{37}$
You still need to double check your arithmetic from back here
Simon James B
Check the right side
Simon James B
No just evaluate the right side
How did you work out 5^37
Reduce it to a whole number
IDKK
Do this first $(5^2)^{12}$
David
5^24
Yes so 5^24/5^23=...
5
-5?
So the right side is equivalent to -5
Now put that together with your answer for the left.
hold on cuz idk what is the answer from the lest side
Ping me when you're ready
I do not understand this problem at all.
- (2)^73 / 2^144 - (5^2)^12 / 5^23
- 2 ^146 / 2^ 144 - 5^24/ 5^23
-2^2 - 5
-4-5 = -9
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Yes
.close
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pls...
Click on "mode"
ok
That's in radians.
Convert it into degrees.
And in the 4th row, change to DEGREE instead of RADIAN
In my limited experience studying physics, you only need degrees
Ok thnxs
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does a polynomial like f(x) = (x+1)^2 (x-2)^2 have a vertex when graphed?
From the given function there are definitely 3 vertex
2 lies on x-axis which are zeros of the function and 1 above x-axis
x< -1 fn , x (-1,2) fn , x >2 fn
yeah- got the x intercepts
Did you try graphing it?
You can expand f(x) and solve f'(x)=0 which instantly gives 3 critical points
I did after, I've never seen a graph like this one before so I got a little confused.
minimums and maximums right?
But in this case its unnecessary because you can guess how many vertex
Ye
Guess: f(x)=0 has 2 double roots so they act as vertex as well, between them must also have 1 more vertex otherwise the graph doesnt exist
Double roots act as vertex because f(x) doesnt change sign through those points
Ye, expand, solve f'=0
whats that little ' for?
f'(x)=0, to be more clear
Notation for derivative
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What?
how does bro see this
ššš
why cant you use usub
I have not learned of any such trig sub yet
Iām supposed to
the next thing that came into mind would be u = x² that would cancel an x
and then another linear substitution with u+4
Bro what is linear substitution
I just started Calc 2 bro ššš
I can only use u sub
when you substitute something in the form of ax+b
that's also u-sub lol
just a fancy name
Oh
yea try u = x²
I assumed it was some crazy bs idk
What am I to do with this Z
did you first apply the u-sub
Am rn
Ngl bro he did not prepare us for a lot of the questions on this hw
How are they assigning this after 1 lecture
@faint gorge
you forgot the dx and to change that into du
anti-algebraist šødĻnš²Ā²s
And then another "u-sub" let's call it z and that will be z = u+4
and then use power rule
Where does the * 1/2x come from
differentiate u = x^2
So u sub inside u sub?
basically and that's pretty common
you could have done u = x²+4 too but I was afraid that would be too much at first
anyway gtg u will figure it hopefully
If you donāt mind would you also tell me how Iād go about this?
same
it's the very same procedure
rewrite everything in terms of u and change dx in terms of du
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can i get some help solving this
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1. I don't know where to begin.
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1
what have you tried?
i really dont even know where to start so nothing yet
What can you do to the left side to get just s by itself?
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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.
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
1
draw a sketch
how?
well you could start by getting a pencil and some paper...
I see an equation. is it in a standard form that you recognize?
if not, can you put it into one?
it says ellipse. is there something in your book or notes about an ellipse?
wanted to confirm this is the sketch
I mean it's a graph so sure
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For Calculus 2, how do I get the volume for this ? I'm honestly very confused and don't know how to do it on paper.
,w plot y=x^2, x=y^2
do you know the disk method
Kinda, it's using the area of the circle as the first step, right?
yes.
$\int_a^b \pi (r(x))^2dx$ or in terms of $y$, where $r(x)$ or $r(y)$ is the radius function.
;(
but here, there is 2 radii.
So for x, it'd be pi (x^2)? then y, pi (y^2)?
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i made a GP like:
a/r^3, a/r^2, a/r, a, ar, ar^2, ar^3, ar^4
3rd * 5th = a^2 = 49 => a=7
nvm
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idk how to solve
what i tried :
took b as the common diff, a as the first term, thought of it like an AP
but idts im going anywhere with that
You should start by calculating m
There's quite a limited number of values for a and b to try so it shouldn't take long to just count the elements of R
wont that waste time, if i try finding it by counting?
anything beyond n=3 results in 0
so if m >= 3 you only need to go upto n=3
ah wait you still need m though
yeah you just need to count then
yes
I think you can use binary here? not sure but give it a try
what is binary?
yeah no that is too overkill
you can simply determine the row by trial and error
(if you notice that you can determine the first and final number of the row)
for example, to know 8 is in what row, guess that 8 is in-between 7 and 10
the first and final numbers of a row also have a formula that is easy to derive
what i would recommend is to write the upper and lower bound of a row as a formula of k
notice that the lowerbound for each row is 1, 2, 4, 7, 11, ...
1 + 0 = 1
1 + 1 = 2
2 + 2 = 4
4 + 3 = 7
7 + 4 = 11
one can see that as the pattern continues, the second term increments. thus this is a quadratic trend
likewise for the upperbound
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Now, solving the recursive relation gives L(n) = n(n+1)/2.
Also, the start term of nth row is nothing but L(n - 1) + 1```
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oh well i did it a little differently, i got it tho
Result:
5356
looks like it does contain 5310. Congratulations
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need to write the negation of this
i.e f is not increasing smth
My attempt
f is not increasing if $f(x) \geq f(y)$ for some x,y such that $x<y$

negation of < is not >
i forgot the difference between increasing and strictly increasing
so wasnt sure if i had to include equals to
Theyāre the same
they are the same
There is a difference between increasing and nondecreasing
i thought increasing was >= strict increasing was >
for me increasing and strictly increasing are different
i guess 1 2 3 3 4 is increasing but not strictly increasing
but it seems like the question writer doesn't bother to make a distinction between the two
Well either way the given definition of increasing in this question is f(x) is strictly less than f(y) for x<y
So what is the negation?
the distinction is important
f(x) < f(y) whenever x < y implies increasing but the converse is not true
š ?
In this case, yes
idk who put that i think it was arya but 
it was OP making changes to their latex
if you're required to entirely negate it, should look like:
||f is an increasing function and there exists x < y such that f(x) ā„ f(y)||
however, I think you want something different
ii
:p
increasing function ?
:p I assumed you wanted to negate the whole statement, turns out it only requires you to negate the increasing property
No lmao, one is ¬(p -> (q -> r)) other is ¬p -> ¬(q -> r)
they're not the same
So basically, what you wish to express is: \ f is not increasing if $\exists x, y,$ s.t. $x < y$ and $f(x) \geq f(y)$
s.t ?
thanks
nope
i should make a truth table to check that right?
or simplify, it's easy to do that
š
Lmao, you should get back on topic
I need to go too. I'm running late on my Curves n Surfaces assignment
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A password contains the digits 0,1,...,9 with no restrictions, except it has to have at least two and at most four digits. Also, the password must contain an 8. How many possible passwords are there?
no i get much more
how much š
wdym
oh yeah, it's jsut a conicnidence
wait so itās much higher
like you missed 10 paswrods and found 9 extra
well you started from 10, there are 10 passwords less than 10 i forgot about 8 facepalm
but you still got 18 anyway
the right number is 19
okay
but for example, from 100 to 199 there are 19 numbers right?
and from 800 to 899 there are 100
and from 200,300,400,500,600,700 and 900 there are also 19 numbers for each of them
so
isnāt it 19*8+100?
or am I missing something
now you're missing 19 from 000 to 099
008 is valid
sure
its a password, not a number
oh
that's why they said no restrictions
ohh
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ok final answer 3729
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My book tells me that a function such as the one on the upper part of the image cannot have a primitive function because of darboux's theorem.
However could a function such as the one on the bottom have one?
Thanks in advance
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any idea on how to integrate this
lemme try
wont it come like this
nah it seems way too complecated
ther's gotta be a better method
ight lemme try soemthing
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rak³en
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BRUH
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Kind of confused as to How I'd sketch this
jacobian 
it's pretty simple to see the region 1 ⤠u ⤠2
the region 1 ⤠uv ⤠2 is a little harder but still very doable
Oh, I thought one of the axes was a hyperbola here š¤¦
It's the region between two hyperbolas is it not?
sure seems good
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Evaluate $\int \int_{S} x^2 y^2 dy$ where it's bounded by $y=0, y=x, x+y=1$
What a wonderful world!
So like the integral before I change the order would be
$\int_{0}^{0.5} \int_{y}^{1-y} x^2y^2 dx dy$
I think you mean y to 1-y right?
and do you have to use a change of variable?
Yes
What a wonderful world!
well you said the transformation was y = v, x = 1-u if you move stuff around
yeah
oops
that works too
yeah, best thing to do is graph the transformation
I am
you kinda have to in order to know the new bounds
oh good
oh I gotta go for now sorry, hopefully someone else can help or you can finish it off š«”
Why would this go from 0 to 0.5
I think 0 to 1
y=x intersecst y+x=1 at (0,5,0.5)
no my bad
yea
you are right
now what's the sub you plan to do
so is $\int_{0}^{0.5} \int_{y}^{1-y} x^2y^2 dx dy$ fine?
What a wonderful world!
yea
this wont do anything
maybe u = x² and v = y²
if think anything else would make it worse than it is
What a wonderful world!
Is that right
I think the jaboian is missing
oh right
I can manage that
is it fine other than that
I want to ensure I know how to change the limits easily
the bounds for u might be off
Hmm?
x = (1-y) and x² = u
So u = (1-y)² = (1-sqrt(v))²
and for lower x = y then x² = y² = v
yea
I feel this sub made things worse lol
Let me check if my book suggests any subs
[ \int_{0}^{0.25} \int_{v}^{(1- \sqrt{v})^2} uv \cdot \abs{J} : du dv ]
anti-algebraist šødĻnš²Ā²s
ok then let's do that
so $u= \frac{x+y}{2}; v= \frac{x-y}{2}$
What a wonderful world!
ok
I don't think this helps much
y in [0, 0.5] and x in [y, 1-y]
Yeah, trying to sketch the region though
I think you need to get the intersections
yeah, trying to figure that out
well that's here
and then plug them into your substitution and draw the new intersections in the uv plane
wait
so I have x=u+v
and y = u-v
one boundary is x=y
so u+v=u-v
so v=0
another boundary is 1-y=x
so 1-(u-v)= u+v
so 1-u+v=u+v
which gives be u=1/2
which is very sus
Any suggestions
The new points are (0,0), (0,0.5) and (0.5,0.5)
How did you get that
the intersections of this plugged into the sub
What I did was,
uh
x=y
so u+v=u-v
so v=0
then $u+v=1-(u-v) \implies u+v= v+1-u$
What a wonderful world!
so u=1/2
(u,v) or (v,u)?


