#help-27
1 messages · Page 286 of 1
no
There are always "exceptions" to the rule, which is why you should always verify your conclusions with other possibilities.
if you dont know what is the meaning of x^2 then you should check first
i meant your conclusion is in the other direction
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I’ll ping mods next time 🙂
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I keep on getting B as the right answer
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You use the average valume theoroem so it should be (1/(6-0))* the integral of the funtion from 0 to 6
so the integral is therefore pi - 3
by finding the area under the curve
sorry, 4pi - 3
and then that gets divided by 6
to get (4pi - 3)/6
recall that speed is simply the norm of the velocity, so the direction in which the object is moving does not matter.
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not sure where ive gone wrong but i cant seem to get any of them answers
you didnt find the velocity constant?
i found it was like 8 or something but i dont think you integrate the constant to get to the distance and im pretty sure i tried and it got me still nowhere near
you have to, because integrating a constant c will give you ct which is part of s
its important
,w int(1/t +4/(2t-1)^2 )dt
Result:
8
vc=8
,w int[ln(t)-2/(2t-1)+8]
hold on give me 2 seconds
alrighty
holy moly
dude when i tried it before with integrating the constant i didnt write it down i did it in my head
and cause it was 8t my and t was 1 i forgot to change the t value for that one
it gave me the right answer
i gotta start sleeping more dude holy jesus
i hope so dude
eating dinner at 2am cause i had work until 12.30 ruined me
that was 4 weeks ago and my sleep schedule hasnt recovered
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Hi, I'm working on a topological proof of the fundamental theorem of algebra, in this proof I am reading they show that the polynomial f composed with Gamma, where Gamma is the circle of radius R in the complex plane, is homotopic with a nowhere zero homotopy to a0g2 for some value of R, where a0 is the (assumed to be non-zero) constant coefficient of the polynomial and g2 is the function g(x) = e^2nipi. I understand this proof, but I've been trying to prove it more directly by showing that the homotopy given in the second screenshot is nowhere zero, could I get some help please?
Please do ask if more context is needed, what I've tried so far is the reverse triangle inequality on |h_Gamma| but I believe the approach doesn't work for s = 1.
Also sorry I've used different variables in my work for consistency with the rest of my writing, hope it isn't too confusing once again I'd be happy to clarify
Obviously treating the case of s = 1 separately is trivial, what I meant to say is as s gets arbitrarily close to 1, (1 - s) gets arbitrarily small so any value of R we fix will not be a sharp enough bound for some s close to 1
@dry robin
@fringe idol Has your question been resolved?
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✅
@fringe idol #point-set-topology may be a good place to ask. Or perhaps #alg-top-geo-top? 
you're free to ask here as well. But usually more advanced questions don't get much engagement in these general help channels
Haha I get it, been using this server for 3 years now and yeeeep definitely noticed fewer responses 🤣
Glad to know im getting to the “more advanced” level
introductory analysis and point set topology is about where the help stops here.
yeah makes sense, normally I’d spend more time thinking about this myself but I’m busy tomorrow and the day after and it seems to be more annoying than anything actually thought provoking so I thought I’d look here for help
but I totally understand if not
but yeah I’ll see if I get a reply, thanks for redirecting me!
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Hello can someone help me verify my work?
@sacred vapor Has your question been resolved?
@sacred vapor Has your question been resolved?
@sacred vapor Has your question been resolved?
(A) is not correct
To properly fill out the table for A, test values like 0, pi/2, pi, 3pi/2 instead
Only testing multiples of 2pi will (unsurprisingly) only give you the same points
You also tested those multiples wrong, recheck the x-coordinate
You also did not graph what you have correctly
instead of plotting (8,4) at (8,4)
you seemingly plotted (4,4) at (4,0)
Oh my God you actually found my post
Is that the only part that’s not correct?
Have you considered that I haven’t checked yet, given A is already this wrong?
no sorry I was hoping that was the only thing wrong
mhm, not an answer to your problem, but rather a heads up: you might find faster help in the physics server 
that would be discord.gg/physics
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This is almost pure math though
✅
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<@&268886789983436800> please move this channel out
Kekw
what?
the helpers really want to see 0 help channels
and this one just hasn’t left for a while
Hours
i cannot move the channels manually in any case, itll break the bot
you mean 40 minutes
also im pretty sure the bot will never move all the channels out because that is literally impossible to do in discord
It has been done before
yes
how does that work
Either that or the image we saw was photoshopped
it certainly cant be done as a regular moderator
maybe API calls bypass this limitation
cant you do .forceclose?
huh
is that not a command
i dont see why itd exist in any case
the reason there is a delay in moving channels is because of API limits on the bot's side
i think im scizophrenic
us asking nicely doesnt magically get rid of these API limits
i swear there was a command that instantly sent it to the shadow realm
(not true)
if there is its not documented anywhere and not in bot/plugins/clopen.py
specifically, make_hidden() is only called at one point in the code, during the scheduler
to my knowledge there is no way to manually invoke the scheduler on a specific channel
(i know the channel is hidden now so yall cant respond)
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Need help with all parts
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i wanna check my work, i am asked to approximate the integral using midpoint rule
looks about right
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✅
,w rienmenn sum sin(\sqrt{x} from 0 to 8 ,with 4 intevrals
Wolfram Alpha doesn't understand your query!
Perhaps try rephrasing your question?
Click here to refine your query online
Poor riemann
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how to solve this
!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
@lusty stone Has your question been resolved?
that's the problem
<@&286206848099549185>
To find the height of an isosceles triangle is an easy task. Draw the perpendicular from the vertex A to the terminated line BC. Use congruency of triangle to prove that the perpendicular would also bisect the side BC. Use pythagoras theorem to find the altitude.
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Alr so i had this math problem on a test and i didnt know what to do at all so if someone could help me so the basic translation for the text is:
set the angle at which the curves are cut
We have this formula that i think we’re supposed to use im not to sure it goes:
a^2k^2-b^2+l^2=0
If anyone decides to help just ping me
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Law
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You cant reopen this channel
well whatever
Create a new one
u sure? its still here
Yes, do not worry
channel is closed so you won't be occupying two
Takes a few minutes for channel to get reset
alr alr ty
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having trouble understanding what this question is asking
can the rule to form a new heap be anything?
like say i have n=7 , can i have 4 and 3 then 2 and 1?
yeah, then 2 splits into 1 and 1
then 4 splits, maybe 3 and 1 then 2 and 1 then 1 and 1
6 splits overall
They never said we can't split stones 😈 Makes the sum infinite by grinding up the stones
Nope you have to split all heaps! Otherwise how do you end up with n heaps of 1?
the n-1 moves wont make much sense then
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If I have some set A, and some set B, and im asked to find the intersection between them, for an assignment for a class, is it proper to return a set of elements, or set builder notation of the set.
Like if the resulting set is {5, 11, 17}, and using the sets directly, I obtained {2m+1 | 3k - 1 = 2m + 1 and m,k are natrual and k <= 7}, is this okay?
I understand {6k - 1 | k is natrual and <= 3} is also an equivalent set but the set i "obtained" is directly from the given the sets and rules of algebra so i assume it would be a better answer?
I also like it more since it shows explicity where the answer arose from analytically
proper is up to you, i suspect a teacher wouldn't really care but most people would not use set builder for a set that only contains three elements
good question idk
since all those are just equivalent ways to represent the same answer, pick whatever is easier to represent your answer
If you're unsure, why not both?
write both
Giving two answers to math problems always goes well and never causes issues ever /s
set builder might be better for a set with either infinite elements or finitely many elements that you're too lazy to write
but yeah no harm in both so long as you're positive they're equivalent
Alright cool, I just like the way I did it since it is explicity the answer from the given information
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I also like the way you did it
thank you
Though I suspect {5,11,17} would be more than enough, but writing both doesn't hurt
true
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tangents are drawn to circle x^2+y^2=8 at the points where the line x+2y=4 intersects the circle. Find the point of intersection of tangents
!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
well start by finding the points of intersection
!show
Show your work, and if possible, explain where you are stuck.
cool
The line is x+2y=4
first find the points of intersection
ok
with the circle how to do so?
x^2+y^2=8?
need to replace alpha and beta here?
you have $x=4-2y$
ƒ( wai ina teacup)= I don't know
ƒ( wai ina teacup)= I don't know
my hint says to replace x^2 to xalpha
and y^2 to b beta
and write eqn as xalpha + y beta =8
but i don't understand how they did this
what
yea
which formula?
for tangent to a point on a circle first
and then a formula for the solution of the two tangents
i have a time limit on the test can u tell me what formula to use
how much time you got left?
surprised you got a test so close to xmas
after 1 week
This looks like a JEE type question
ye
hm?
i mean in jee i won't have time to solve this lengthy method
no i still have a year for jee
ah
ah
this question is from the blackbooks author
Okay, so I'll derive the formula first, you understand than and then use it?
k
I mean i can do the calculation part
I'm talking about in general '
okay, so firstly, supposing an arbitrary circle centered at origin and a line $ax+by +c=0$, the points of intersection are
\
[
x = \frac{-\sqrt{b^2 \left(a^2r^2 + b^2r^2 - c^2\right)} - ac}{a^2 + b^2}, \quad
y = \frac{a\sqrt{b^2 \left(a^2r^2 + b^2r^2 - c^2\right)} - b^2c}{b \left(a^2 + b^2\right)}
]
and
[
x = \frac{\sqrt{b^2 \left(a^2 r^2 + b^2 r^2 - c^2\right)} - ac}{a^2 + b^2}, \quad
y = \frac{b^2(-c) - a\sqrt{b^2 \left(a^2 r^2 + b^2 r^2 - c^2\right)}}{b(a^2 + b^2)}
]
\
Then differentiating the equation of the circle, we get $y' = \frac{-y}{x}$ or
$y ' = - \frac \frac{a\sqrt{b^2 \left(a^2r^2 + b^2r^2 - c^2\right)} - b^2c}{b \left(a^2 + b^2\right)}}{\frac{-\sqrt{b^2 \left(a^2r^2 + b^2r^2 - c^2\right)} - ac}{a^2 + b^2}, \quad}$ for one line and
\
$y' = - \frac{\frac{a\sqrt{b^2 \left(a^2r^2 + b^2r^2 - c^2\right)} - b^2c}{b \left(a^2 + b^2\right)}}{\frac{-\sqrt{b^2 \left(a^2r^2 + b^2r^2 - c^2\right)} - ac}{a^2 + b^2}, \quad}$
|
ok
Supposing an arbitrary circle centered at origin and a line ( ax+by +c=0 ), the points of intersection are
\
[
x = \frac{-\sqrt{b^2 \left(a^2r^2 + b^2r^2 - c^2\right)} - ac}{a^2 + b^2}, \quad
y = \frac{a\sqrt{b^2 \left(a^2r^2 + b^2r^2 - c^2\right)} - b^2c}{b \left(a^2 + b^2\right)}
]
and
[
x = \frac{\sqrt{b^2 \left(a^2 r^2 + b^2 r^2 - c^2\right)} - ac}{a^2 + b^2}, \quad
y = \frac{b^2(-c) - a\sqrt{b^2 \left(a^2 r^2 + b^2 r^2 - c^2\right)}}{b(a^2 + b^2)}
]
\
Then differentiating the equation of the circle, we get ( y' = \frac{-y}{x} ) or
[
y' = - \frac{\frac{a\sqrt{b^2 \left(a^2r^2 + b^2r^2 - c^2\right)} - b^2c}{b \left(a^2 + b^2\right)}}{\frac{-\sqrt{b^2 \left(a^2r^2 + b^2r^2 - c^2\right)} - ac}{a^2 + b^2}}
]
for one line and
\
[
y' = - \frac{\frac{b^2(-c) - a\sqrt{b^2 \left(a^2r^2 + b^2r^2 - c^2\right)}}{b(a^2 + b^2)}}{\frac{\sqrt{b^2 \left(a^2r^2 + b^2r^2 - c^2\right)} - ac}{a^2 + b^2}}
]
\
ƒ( wai ina teacup)= I don't know
We then find the equations of the tangents using thsi
what
then xx1+yy1=8
Let me see if my jee books have a formula for this( older ones)
@lost laurel oh you're indian?
yeah, but I didn't really care much about JEE
did u give jee?
Yeah
oh
so not great, yeah
its great for first attempt
any general tips for me?
take breaks for one thing
ye i do take breaks
I didn't, even during my drop year, I regret it now
oh
next focus on concepts
i study from vikas gupta
online
for maths
which books should i use
currently im only doing resonance modules
I used arihant books
and for maths vikas Gupta's sheets
meanwhile me who watches lectures most of the time
And solves books / modules rarely
🤡
yea
one whole year atleast
can i complete 12th syllabus in 4 months
if i study 12hr+/ day
daily
consistently
i will drink coffee
For instance, I'm currently doing maths at uni, I used to study 12 hours a day for most of the semseter, was so burnt out towards the end , that I didn't study during exam week and the week before that
anyway, back to your question, i"ll look for a formula
i studied 15hr in 10th for 2-3 months
Near boards
💀
got 92%
fucked up sst
and hindi
ye
effective study time was around 12hrs
xx1+yy1+g(x+x1)+f(y+y1)+c=0
i think they used that here
but there are no terms for x and y and constant
this is the eqn of a tangent formula
looks familiar
yes
so you'll need the points at which the lie intersects the circle
the circles formula is x^2+y^2=8
no
(x1,y1) is the tangents coordinates
so they made two eqns for the tangents
and they should be the same
okay, so that makes sense
,w solve x^2+y^2=8 , x+2y=4
wrong answer
wrong
that's better
Answer is incorrect
this is the point of intersection of the line and circle
so from this you get the equations of the tangents
and then you can find where the lines intersect
I just saw the solution
it says x+2y=4 and xalpha+ybeta=8
and then a1/a2=b1/b2=c1/c2
so u get (2,4)
alpha/1=beta/2=8/4
but how
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Given triangle ABC. M, N, P belong to BC, AC, AB so that BM = 3CM. CN = 2AN. AP = 4PB. I, J, K is the intersection of AM, BN, CP. the area of triangle IJK = 2. Find the area of triangle ABC.
@mighty plover Has your question been resolved?
wait
<@&286206848099549185>
CN = 2AN
i guess it's not drawn to scale then?
@mighty plover Has your question been resolved?
annoying problem
if triangle ABM has the area 3S, triangle MAC will have area S
and if triangle ACP has the area 4P, the triangle BCP will have the area P
and if triangle ABN has the area 2L, the triangle NBC will have area L
from that you'll work the areas of triangles PJB, KMC and INA out in terms of S, P and L
then substract them all from the area of the triangle ABC 3 times
because Area(ABC)=4S=5P=3L
then you'll set those three equations equal
and work out the area IJK in terms of S P L
and find area ABC
i'll see if there's an easier solution
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hints plesae
a lot of theorems are about proving "common sense"
it turns out that the common sense is not always true
ye how do i got about doing this
i wrote my statements
eps delta
but how to relate
yep
i wrote two statements
one for fx, one for gx
how to relate them
you have f(x)<=g(x) to relate them
yes i know
can you be more specific?
|fx - L| < epsilon
|gx - B| < epsilon
i used B because gx has a diff limit than fx at C
what should be my approach now
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Just need a sanity check on this, but [\mathcal F\left{\cos(5\omega t)\right} = \pi\left[\delta(\omega-5\omega) + \delta(\omega + 5\omega)\right]
]
is that correct
Aero
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We're about to learn permutations so Im advance reading right now and I'm quite confused on what the formula nPr means
like
what does the n stands for
and
what does the r stands for
Hello
Hello
nPr is basically how to select r things from n distinct things
can you give an example please?
So say that you have 10 apples
I don't understand it very much
And they are labeled from 1 to 10
Then, 10 P 4 is the number of ways to select 4 apples from the 10, with one condition:
For example, if you select 1, 3, 5, 7 its not the same as selecting 1, 3, 7 then 5
Order matters here, unlike for C (combination)
@valid barn
Can I ask if I'm understanding the condition correctly?
So in Permutations say 1,2,3,4 is different from 1,3,2,4
While in combinations
1,2,3,4 is the same as 1,3,2,4?
yes, combinations dont care about the order
Yes
So in Permutations we have a lot of answers while in combinations we have less?
the number of permutations in a set of n elements is n!
how about combinations though
n!/p!(n-p)!
no, permutations is n! /(n-r)!
Ya
Alright ty fellas I'ma come back again if I got any other questions
Permutations: nPr = n! / (n-r)!
Combinations: nCr = n! / r!(n-r)!
thats a particular case of permutations
but if we want to find n permutations in a set of n elements its n!
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yo chat sorry
rak³en
back to this
Have you considered king's rule
@stone stump (sorry for pining) k is a real number to ensure that this integral doesn't diverge 🙂
no, thx for reminding meh
$$\int_0^1 \frac{(1-u)^a}{ku + (1-k)} \sqrt{\frac{1-u}{u}} du$$
rak³en
pret sure this is the same as subbing in 1-u = z
WA (for alpha =0 and 1) began by subbin in $\sqrt{1-u} = s$, can't simplify it tho
rak³en
@finite briar Has your question been resolved?
<@&286206848099549185>
みなさん てつだってください
hmm
how do i partial fraction $\frac{x^{m+2}}{1-ax^2}$? $a$ and $m$ are arbitary non-negative integers
rak³en
jesus you need polynomial long division first
thats...inconvenient, I guess
rip
how do I even do long division with a variable power
like how do you know when you reach the remainder term
because you'll have like m-something right
and u will just keep getting that
i dont think you can
but i might be wrong
if there is it will be something horrible
and recursive
hmm
@simple seal can't seem to find a pattern, did you?
show me what u got
errr lemme make it a bit non rough
how do you think kings rule is derived
I dont remember honestly
but I assume that it is how its done
@finite briar Has your question been resolved?
@simple seal
I can see the pattern...but how do I write this as a sum? Cus else I won't be able to integrate
<@&286206848099549185>
yes
@simple seal why do you think they're wrong?
theres a x^9 in the last line which seems off
thats not 9 thats 4 💀
mf that is oiterally a 9
anyways
probably easier looking at evens and odds individually
😅
and see if you can find a way to combine
hmm let meh seh
@finite briar Has your question been resolved?
is it horrifying
show me
partial fractioning this gives and putting in $x= \cos(x)$, $m = 2\alpha$, $a=k$ should give you the target integral
rak³en
ahat is the target integral
.
ah
okay so i solved $$\int_0^{\frac{\pi}{2}} \frac{\cos^{2\alpha+2} \theta}{1-k \cos^2 \theta} d \theta$$
which is different from what I wanted
rak³en
yikes
this is..gimme 1 sec
rak³en
$$ 2 \int_0^1 \frac{u^{\alpha}}{1-ku} \sqrt{u(1-u)} du $$
target was
rak³en
but this has a very nice closed form
so whats the goal now
find this, attempt 2 🙂
kings rule?
if u get the time do check if this comes out to be:
$$ 2 \int_0^1 \frac{u^{\alpha}}{1-ku} \sqrt{u(1-u)} du = \sum_{n=1}^{2 \alpha + 2} \frac{1}{2k^n} B \left(\frac{1}{2}, \frac{n+1}{2} \right) $$
rak³en
yowza beta function appearance
yes thats why its so nice
@simple seal its wrong 😭
target integral
once again a different integral
lol
$\sum_{r=0}^\infty k^r\int_0^1 u^{\alpha+r+1/2}(1-u)^{-1/2}\dd{u}$
kheerii
this is the best you can do for general alpha
i turned target into this by accident, then i turned it into trig integral, which i wrongly solved to get that finite series
for integer alpha theres a simplication no?
there might be idk
thats what I wanna find
what's the original question?
this
integers
well then you can't do this
you're gonna need a different approach altogether
cus divergence?
yeah
i am trying to partial fraction the non square rt part
u^a/(1-ku)
Hmm seems tedious
(a is a + integer)
very
I think you should sub u = sin^2 t and then sub tan t/2 and see where that takes you
nani?
oh lol
i didnt run into any divergence issues so it seemed fine
does it converge for -10
should check these things before hand
lemme try that
yes
well you can series expand for -1 < k < 1
but yeah not for negative integers
he said k is an integer though
the tan t/2 sub seems..not good to me
the sin^2 leaves meh with
$2 \int_0^{\frac{\pi}{2}} \frac{ \sin^{2 \alpha+ 2} (t) dt}{1-k\sin^2 (t)}$
rak³en
this doesnt seem like a weistrass sub at all imo
I've a feeling that if I do the painful partial fraction then this is simply a sum of a bunch of elliptic integrals
but I hope there is some other way
deleted question on MSE
😭
managed to write it down back then and found it while traversing the pages of nb
welp i gtg study science
if someone makes progress on this, please dm (or ping somewhere where I dont have have to scroll a billion msgs up)
integration is fun 🙂
i've got another one after this (https://math.stackexchange.com/questions/5014354/evaluate-int-01-frac-lnx-ln-left-frac1-x1x-right-sqrtx)
that is from an active question (asked 12hrs ago)
no answers, only 1 comment by claude sama
I'll leave then
time to ram my highschool brain into it and see if i can do anything (probs not)
a high change no (tho technically speaking am in HS too, so ig you should try it)
the thing is these require a big knowledge of function you know can't be reduced further, or forms that have already been turned into these special functions
like the aforemention, beta function, the gamma function( real factorial ), riemann zeta, direchlet eta
as well as stuff like the sine integral, cosine integral, fresnel integrals
(PS I simply google, and once I goggle I usually remember the definition, and from there its HS integration thinking converting the given form into that form)
looks horrible
have fun
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Hello! How do I get to the DetN and Deti here?
I get how to get the normal det 
hi again
Hi
$\begin{vmatrix} a & b & c \ d & e & f \ g & h & i \end{vmatrix} = a \begin{vmatrix} e & f \ h & i \end{vmatrix} - b\begin{vmatrix} d & f \ g & i \end{vmatrix} + c \begin{vmatrix} d & e \ g & h \end{vmatrix}$
oops
I get how you get the normal Determinante, but how do I get detN? 
well
lemme write
$\det_N = dG \begin{vmatrix} PL_i & L \ 0 & Y_N \end{vmatrix} - (-I_i) \begin{vmatrix} 0 & L \ 0 & Y_N \end{vmatrix} + 0 \begin{vmatrix} 0 & PL_i \ 0 & 0 \end{vmatrix}$
Herels
I get that part, but how do I get to the starting matrix for detN? 
i'll need context for that
I got the det and now the next step would be to get the detN and Deti
yes and you want to know how they got the matrix
For the detN and Deti, yup
what are det_N and det_I supposed to represent tho
I don't know
do you have the whole context ?
No, I will translate 1 sec
Sorry, 1 more sec, it's tough to translate that
in which we replace the corresponding column with the vector of the exogenous variables
He said that, but I don't understand what he means by that
well i saw that they replaced some of the column from the first matrix
for det_N, they replaced the first column of the first matrix
for det_i, the second column
now why did they do that ? i have no idea
np
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Where did I mess up?
I can’t seem to figure out why my integration of 1/(e^y-1) is wrong
Tag me please
@restive river Has your question been resolved?
,w int 1/(e^y-1)
$xdy=(e^y-1)dx$
ƒ( wai ina teacup)= I don't know
ƒ( wai ina teacup)= I don't know
let $e^y=t$
ƒ( wai ina teacup)= I don't know
$\frac{dx}{x} =\frac{dt}{t(t-1)}$
ƒ( wai ina teacup)= I don't know
Yes, but why is what I’ve done wrong?
I don’t understand
I wrote that down with so much confidence
so you subbed $1+e^{-y} =t$
ƒ( wai ina teacup)= I don't know
$e^{-y}/(1+e^{-y}) = \frac{1}{e^y \cdot e^y+1)/e^y}$
ƒ( wai ina teacup)= I don't know
okay, so this sub should work
Integrate bothe sides
Small correction. It’s e^y-1 and not e^y+1
sure, but one issue
ln(x) = int of 1/t(t-1) dt
what's the derivative of e^{-y}-1
-e^-y
I don't think you've written that
I have 1 - e^-y. So the derivative of that is e^-y
$(1+e^{-x} = 1+ \frac{1}{e^x}$
ƒ( wai ina teacup)= I don't know
now ?
Oh hell
It must be like that then
Thank you so much
I appreciate it very much
Have a good one:)
.cmose
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Three different natural numbers $x$, $y$ and $z$ each have exactly three natural-number factors. How many factors does $x^{2}y^{3}z^{4}$ have?
938c2cc0dcc05f2b68c4287040cfcf71
can someone explain what they want me to find?
$x,y,z$ each have 3 factors
ƒ( wai ina teacup)= I don't know
how do you know that, is given but, why is that
which kind of numbers have only three factors
and how does that help in finding the factors for x^2y^3z^4
every number has 1 and itself as a factor
so you're looking for numbers that have only 1 additional factor
primes won't have any, so they're out
have you thought about this exercise? how is the exponent related?
they're talking about all factors not prime factors, i think
so 1 counts
i haven't thought too much yet
i got an answer
i won't spoil unless you want me to
dont spoil
ok
can u give me a hint
start by answering this
like, depends if x,y,z is prime
okay, let's take it case-by-case
what if x is prime, how many factors does it have?
3
2
yes
and do they all have themself as a factor?
1 and itself
yes
all primes have 2 factors
they can't have a third factor
we're looking for numbers with 3 factors
it can't be primes
2
how many factors does 2 have?
2
1
1 has 1 factor
2^3
unsure
1,2,4,8
yes, four factors
too many this time
hint: factors often come in pairs
8 is 1*8 and 2*4
but we only want 3 factors so they can't come in pairs
yeah 6 has 4 factors again
4 = <(4,1),(2,2)>
yes
4 = {4,1,2}
yeah 4 has 3 factors
yes: {4}
NO {primes, 2, 1, 8, 6}
YES {4}
4 had 3 factors because one if its factors was repeated
9
9 = <(9,1),(3,3)>
yes = {4,9}
(x^2)^2 + (y^2)^3 + (z^2)^4 = x^2 + y^3 + z^4
x^4 + y^6 + z^8 := x^2 + y^3 + z^4
5x7x9
oh, you got it somehow
,calc 579
Result:
315
sorry, I am bad at explaining but I think you understand that only primes squared have three factors, 4 = 2^2 , 9 = 3^2 and we coulsve tried with 25 = 5^2
from there we need to find the real exponent and sum 1, this is the tricky part which I dont really understand completely
also there is an assumption being made that we are talking about distinct primes dont we?
it was stated in the problem
different natural numbers, right
yeah
idk how I got it
the nunber of divisors, from the prime factorization, the number of the exponents + 1
someone explained to me for example 2^3 has 4 factors
8 = {1,2,4,8}
2^n have n+1 factors
because 2 is prime
idk, why I cant provide proof, because I havent learnt proofs, but I will try to prove it soon
idk why is true
someone told me I cant remember if it was today or yesterday
you also told me today
I just, find it amazing
Ah
Note that the factors must be of the form 2^x, where 0<=x<=n
Thats it actually
we can generalize it for all the primes
is something I have discovered in the last few days, not only for 2 but for any primes, I will try to find more info about it, if you guys want to comment more about it, please feel free to reach me out
You may want to check out the results for the sum of the divisors and the product of the divisors of a number while you're at it
I will say that the product is more intuitive than the sum
so if you wanna try and discover the results for yourself
I'd start with the product
thanks, i will keep the channel open for a bit in case someone wants to comment other findings
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if you draw square ABCD and extend the sides by equal lengths to form square EFGH, find angle HEB so that the area of ABCD is half the area of EFGH?
Guys what is 1+10???
<@&286206848099549185>
!15m
Sum help pls
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go somewhere else to troll
what have you tried?
😦
it helps to draw a picture
i did
wait a min
?
wait
there's figure on the book lmao
at the back
i let the extended sides be x
if it works lmao
i literally have no idea
T_T
both figures work actually
but i'll go with the one in the book
denote the smaller square's side as a, the bigger square's as b
you know that the bigger square's area is twice as larger as that of the smaller square, so b^2 = 2a^2
you can now calculate the relationship between a and b
denote by c the extended length; in particular, c = HA = DG = CF = BE
using pythagorean you can find the relation between c and a (or c and b)
use trig to find angle HEB
are you following so far?
(a+c)^2 + c^2 = b^2?
what?
i mean, sure
and then what?
but please read everything i said again
start here
yes
how?
b^2 = 2a^2
what do you propose to do?
such that on one side you have only b, on the other side you have only a (with some extra numbers)
b = a * sqrt(2)