#help-36
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resistivity is a property of the material, isn't it
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✅ Original question: #help-36 message
wait ik my teacher told me that 2
but rho = RA/L
here resistivity seems to be dependent on area and length
it's like saying density varies if you cut a material in half
R varies too
there are two kinds of properties, intrinsic and extrinsic properties
intrinsic properties are always (ideally) constant for a material (I mean there are factors, but we usually ignore them at elementary level)
if it is a copper wire and you do that to it, it won't transmute alchemy-style into an iron wire
it'll remain a copper wire and have the resistivity of copper
and things like density, resistivity are intrinsic
do keep in mind, this is not the be-all and end-all formula for resistance. The resistivity, cross-sectional area, and current density are all assumed to be perfectly uniform throughout the material
ok
why is it so?
like
ok they dont change bcz of their behaviour
there is ntg more to it right?
The actual formulation would be [
R = \4{\int \vv E\vd \dd\vv\ell}{\iint \vv J \vd \dd\vv A}
]
generally
but i reckon you dont have to worry about that
why is give integration twice in the denominator?
wait this isnot school lvl right?
it's extremely NOT school level
ok then I will stop here I shouldn't go any further yet with this
thnx everyone here for helping
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Hi! I am trying to figure out how I would solve this! The question asks “What interval of amounts of cheese represent the middle 60% of amounts dispensed?” The mean is 3 ounces and it has a standard deviation of 0.2. I am just confused on how to get middle percentage.
I think I might have found the solution could anyone let me know if it is off?
I am still mastering telepathy
Sorry I thought it sent😭
but using the top and bottom how would you calculate to get the middle percentage
can you send the entire question please
stats
!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
2
mari is that the answer key
oh
Im confused on how to continue 3D
It says to get the middle 60 percent
So i assumed I should get the top percent and bottom
it's correct
I think it means between 20% and 80%
Oh so just put it as an interval?
yes
its kinda clicking now
IG middle usually means equal parts above and below the centre
okay thank you guys :))
no worries sending u love
lol thanjs
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Is my work right
I assume ms is milliseconds?
Yeah
one way I saw someone do it is
imagine if it's 5 seconds to millisecond
we know that 1 second = 10^3 ms
so just replace the second with 10^3ms
so it goes from 5 seconds to 5 (10^3 ms), and then just get 5*10^3
But my work is right, right? I wasn't sure how we got the exponent of 6 because one of the 3's were negative so I just flipped it
yeah yeah it's fine, you could just write it a bit more systematically though
Alright thank you, imean I didn't make anything up right
yes yes, solving wise it's fine
@tough crystal Has your question been resolved?
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i don't understand this proof of cantor's theorem
like ok, a € X, ergo a !€ f(a)... so what?
i don't see how we get from a € X to a !€ X
where do we get that second part from
If f is a bijection
in this case f is surjective
hold on
Is a in X or not in X?
why is X = f(a)?
f: A->P(A) is surjective
it's an element of the codomain
So X must be the image of something
right?
right
So, X = f(a) for some a
ok following
well didnt we just say it isnt?
Well, if a is not in X
Then a is in f(a)
Because that's what it means not to be in X
But this is "a is in X"
So, "a not in X" implies "a in X"
That's not possible
So does that means a is in X?
Well, the other way around
If a is in X
Then a is not in f(a) (definition of X)
Then a is not in X (f(a) = X)
goooot it
ok ok i see now thanks
and that's russel's paradox right?
at least it feels like it
Well it's close
Russel's paradox is that there isn't a set of all sets
Otherwise you can create the set of sets that don't contain themselves as an element
well it's the same kind of short-circuit where a -> !a -> a -> !a ...
so "x not in x", a bit different from "x not in f(x)"
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huh?
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For number 10 if f has a derivative everywhere on [a,b] isn't f' defined everywhere and thus continuous and then you can just apply the intermediate value theorem directly?
"defined everywhere and thus continuous"
why thus?
derivatives don't have to be continuous
they can't have step discontinuities but they can have the "oscillate to death" kind
f(x) = x²sin(1/x) prime counterexample (with f(0) = 0)
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I have a quick question with math that should be fast to solve. It regards problems such as
0.000000000001 = 1.00 x 10^-11 = 1.00e-11
That is an example problem and I have a few more I tried to solve but the system keeps saying I’m getting it wrong so if someone could look over it for me please 🙏
try e-12 instead of e-11
you counted wrong
The first one is an example
its not -14
lmao oops
but ngl if its not that, the rest seem correct
now that Im looking at it again, -14 looks correct...
thats no good
oh right
4.74 not 4.70
Ohhh let me try that
Ok I got the rounding wrong for the last one but almost there
also, 4.98149 does not round to 5.00
keep in mind you have three significant digits
that means 4.98, not 5.0
I got it!!
Thank you
This problem was killing me and I couldn’t figure out why despite being close 😭
np
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Did I convert everything right?
Ignore the random letters, that was me marking that I wanted to check it lol
good
the exponent is -3, not 3
good
probably fine ... depends on rounding rules ig?
also you can check this in #bots
ex:
,w (810^3)(2.3785*10^4) scientific notation
She didn't state what it was so Im not sure I just left it at what my calculator ended at
yes
Okay thank you so much and thank you about the bot, that's good to know

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@restive sinew Has your question been resolved?
do you know GENERAL solution of sin(x)=0 for all real x? @restive sinew
@restive sinew Has your question been resolved?
i am not curious about that
i am thinking what formula they used for z=n case
sinx=0 when x=n pi
and it is obviously written there
i am asking what did they use it here
okay i got it by simply google search
thanks
they used this formula
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It's just the residue at a simple pole
You can get that form with g'(z0) in the denominator by performing L'hopitals
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can someone please explain this binomial problem?
ok
nvm but uh, i'll alert helpers in the discussion cause this is not within what I know
oh ok thanks though!
another thing cos i forget binomial lol
ok
seems like everyone's busy
if there's no one after 15 mins just ping helpers]
or what I like to do is ask chatgpt to teach me through, although I don't recommend it to tell you sols.
alright i think thats better
cos most helpers are on the american side, so its kinda night time for them now
theres a handful of us in the asian continent but not a lot
i can refer you to another one...
Oh ok thanks
Could you briefly explain where you are stuck at?
the whole thing i understand whats happening with the dice but not how they get each binomial
Because there are only 2 results
Success or not
It does fulfill the requirement of being a binomial situation
i see but why is there p(x=0)?
i get that throw the dice four times but whats the 0 for
You get no success in the 4 attempts
No worries, anything else?
nope 🙂
Alright, have a good one 
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dw
ty
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Hey! I'm trying to find a reliable way to compute the normal direction of a 3d plane given the positions of it's four points/corners. Let's say we have a random point generator that spawns points on an irregular ground surface, forming a 3d plane at any of these points would cause the plane to intersect with the surrounding ground surface since the individual spawn point up vector (which is used by the plane) does not account for the 4 corner points of the plane. So my solution is to get the 4 corner points of my plane (p1, p2, p3, p4) and snap them to the surface right below them and then calculate the plane normal direction from these points instead.
For my usecase, I've determined that computing the normal direction using only the 3 points of my plane isn't sufficient enough for getting the least "interesectable" orientation for the plane if that makes sense. Imagine the top right point (p3) as the final third point used for computing the plane normal direction, if you rotate that plane 45 deg around itself such that that the top left corner (p4) is facing a steep ramp, and you move that plane towards that ramp, the plane normal direction wouldn't get updated at all and you would get an intersecting plane, unlike if you rotate the plane -45 deg such that the third point (top right) is facing that ramp, which then it would update the normal direction correctly.
My first solution was to get the halfway point between the top two as my third point:
vector p3 = p3-(p3-p4)/2;
vector N = cross((p1-p2), (p2-p3));
but idk if that would be a good way to do that.
My other solution was to flip the plane direction horizontally to use the fourth point as the third point and get the median vector between the two:
vector N1 = -cross( ( p1-p2 ), ( p4-p2 ) );
vector N2 = cross( ( p2-p1 ), ( p3-p1 ) );
vector N = ( N1 * 0.5 )+( N2 * 0.5 );
Seems to work a bit better than my first method but I'm still wondering if there's a correct way to do this (:
@spring basin Has your question been resolved?
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✅ Original question: #help-36 message
@spring basin Has your question been resolved?
I did not understand any of that and I suspect I'm not the only one who tried. You probably should post a detailed picture of a problematic situation and then describe precisely why it's problematic and what you would want instead, ideally with another picture or drawing.
@spring basin
ahh I see, well that makes sense why no one was replaying haha, I'll try to demonstrate the problem a bit better
<@&268886789983436800>
?
<@&268886789983436800>
what
you're not owed an explanation for someone modpinging
don't post inappropriate gifs in help channels
shitposting goes in #chill
Yeah, not particularly a smart idea to send annoying .gifs in a help channel and then try and ping us
have a day off 
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So far this is what I have:
If $W$ is not full rank, then $\operatorname{det}W = 0$ and also $\operatorname{detA} = 0$ as $A$ is also not full rank.
If $W$ is full rank, the rows of $V$ are linear combinations of the rows of $W$, so by subtracting multiples of the rows of $W$ we get that [ \operatorname{det}A = \operatorname{det}\begin{pmatrix}U&0 \ 0&W\end{pmatrix}. ]
kheer257
How do I show that that last determinant is detU * detW?
I know I can just induct on the size of U but I'm looking for a better way
if you know the formula for determinant using permutations you can use that
mm
well, that or you can do some kinda geometric volume-scaling-factor argument on R^(m+n)
😭
I think I'll just do the induction lol
well actually
is it true that without swaps, any non-singular matrix can be reduced to a diagonal matrix?
@spring haven Has your question been resolved?
row swaps are redundant bc you can accomplish the same via row additions and scalings i think
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<@&268886789983436800>
<@&268886789983436800> user id: 919239993686368336
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hi guys im new into this server
as mentioned ask your question if you need help
or close the channel
use a social channel like #discussion if you just want to chat.
!redir
This channel is only for on-topic discussion. Please take casual conversation to #discussion or #chill.
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<@&268886789983436800> um...
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🤔 what was the matter
I'm not sure how that helped, but I'm glad to have helped!
they deleted their own post, then attempted to dodge consequences by leaving the server.
... what happened
they think they can dodge by leaving
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Why is the set of points [−3,+∞) ? It looks like it's only going till 7.
there is no indication the graph stops there.
Zoom out. Other than that this looks like parabole
i assume you mean the range/image?
so it's assumed that the graph continues forever upwards.
It's just poorly drawn tbh
it stops right before 7, and the drawn graph still continues tho
so how can I assume
круто
Cuz when u give it any number positive it can give u answee
Russian
yep
Its a poorly drawn graph, usually its more consistent to guide yourself using the formula for the function
normally, such a graph should have arrows at its endpoints.
but you can convince yourself using the domain of the function.
when problems are badly stated like this one, you go with what is the most likely intent
Russian speaking*
we are talking about the y values here surely?
yeah
What
um, why is there another conversation ongoing here?
The function u can said it's completely finished when u put number and can't get an answer
whatg does that mean
Like for example
uhh
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Wdym
see #❓how-to-get-help for how help channels work.
I think it's pretty clear what she means
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Given the vertex of the parabola, a point P on the parabola and the angle between line VP and axis, how do we construct the focus using straight edge and compass
@opal plinth I was unable to see your message due to a network issue
How would I construct the tangent at point P
The tangent to x^2 at x=p goes through (p/2,0)
But why are we choosing x² as the paraboal
All parabolas are the same
I guess it will
green = red
Now that I have this tangent
Vertex of the parabola is the lowest point
I guess I can construct the normal
Then I will get my focus
Thanks for the help @opal plinth
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Exercise 2 1st request
Foundations
How can I prove that the power set of the cartesian product AxB on the lhs is included in the cartesian product of the 2 power sets on the rhs
Prove or disprove
Ofc yeah
But what do I use
A power set is a set of sets
Do you think it's true or false?
I think it's true
So I can only
Let X (a set) belong to P(AxB)
But AxB is a cartesian product so it should be 2 subsets
So you would need to write
X = X1 × X2
X E A, Y E B
So you already see a problem
Oh yeah
And at the same it needs to be a couple of sets
Powerset is all the possible sets that can be found from all the elements in a set
How can I use that
So at the same time, X is a set
And a couple of sets (X1,X2)
They're not the same kind of object...
So it's hard to say they're equal
So... Is it a contradiction?
The way the exercise asks, yes
Multiple things wrong
First, $X \subseteq A \times B$ implies $X \subseteq A$ and $X\subseteq B$??
Rafilouyear2026
Oh it doesn't
Did you mix up cartesian product with intersection?
I know it was wrong but I had to turn up with something on google classroom
Can't I say
{X,Y} belongs to P(AxB)?
Is {X,Y} a subset of A×B?
No🥲
Right
But why
(X,Y) btw again
Asking if (X,Y) is a subset of something is wrong to begin with
A point is not a set
Exactly
It's the other way around tho
Ts too hard and our proff didn't teach us
You start with X a subset of A×B
I really doubt it's gonna be in the exam
And you have to prove/disprove that it's = (X1,X2)
Yeah?
Again because points not sets
Exactly
Though, I believe maybe the professor was looking for something else
Instead of P(A) × P(B)
No she told me because it's cartesian I should start with a point?
I know it's worng
Maybe they meant ${X_1\times X_2:: X_1\in P(A), X_2\in P(B)}$
Rafilouyear2026
Ok, then point ≠ set
Or, and this is based on you mixing up cartesian product and intersection
$P(A\cap B) = P(A)\cap P(B)$
Rafilouyear2026
I don't have them mixed up I was just trying😭
I'm the best student in foundations in my college
However out professor gave us the assignment without giving us an example before it
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\textbf{Exercise 1.} Define on $\mathbb{Z}$ the relation $R$ given by
[
n , R , m \iff 10 \mid \left(n^2 + 4m^2 + m - 6n\right).
]
\begin{enumerate}[label=\alph*)]
\item Prove that
[
n , R , m \iff 5 \mid \left(n^2 - m^2 + m - n\right)
\quad \text{and} \quad
n \equiv m \pmod{2}.
]
\item Prove that $R$ is an equivalence relation.
\end{enumerate}
Renato
@gentle zephyr Has your question been resolved?
note that n^2 - m^2 + m - n is equivalent to n^2 + 4m^2 + m - 6n modulo 5, and n^2 + 4m^2 + m - 6n is even (0 mod 2) if and only n = m (mod 2)
,align
10\mid (n^2+4m^2+m-6n) &\iff 10\mid (n^2-6m^2+m-6n)\
&\iff 10\mid(n^2-m^2+m-n -5(m^2+n))\
&\implies 5\mid (n^2-m^2+m-n -5(m^2+n))\
&\iff 5\mid(n^2-m^2+m-n)
Axe
Yeah I think since 2 and 5 are coprime, you can say $10\mid x\iff 5\mid x \land 2\mid x$
Axe
@gentle zephyr Has your question been resolved?
What did you do in the second iff
just algebra
Completed the square
i wanted to make it look like n^2 - m^2 + m - n as much as possible
there's a more direct route
,align
10\mid (n^2+4m^2+m-6n) &\implies 5\mid (n^2+4m^2+m-6n)\
&\iff 5\mid (n^2-m^2+m-n)
Axe
The issue here is the one sided implication
yeah
use this
its not really an issue
this proves the first half of the implication mRn implies 5|... and m\equiv n mod 2
Care to elaborate?
this doesn't address mod 2
right, thats why i said it proves half of the implication
not even half
the implication nRm implies 5|n^2-m^2+m-n and n\equiv m mod 2 can be split into nRm implies 5|n^2-m^2+m-n and nRm implies n\equiv m mod 2, what you have done prove the first part
which i believe is half of this implication
oh, sorry i misunderstood
yep this is true
-# i go through this in a bit more detail in https://pseudonium.github.io/2026/01/18/Products_Categorically.html
np, i figured that you were talking about the equivalence not just the one sided implication
This is CRT or what?
in general it's true that $\text{lcm}(a, b) | x \iff a | x \text{ and } b | x$
Pseudo (Cat theory #1 Fan)
where exactly are you stuck renato
yes
Don't know how to start a)
A lot of hints where given but
Don't know how to connect them
ok so you know nRm\iff 10|n^2+4m^2+m-6n
i would recommend starting with axe's hint
$10 | n^2 + 4m^2 + m - 6n \iff 5 | n^2 + 4m^2 + m - 6n \text{ and } 2 | n^2 + 4m^2 + m - 6n$
Pseudo (Cat theory #1 Fan)
check this, is there something here that you dont follow?
btw does replying to the output of the bot ping the user?
no, it doesn't
ohh ok, thanks for the info
Yes
Now what?
try manipulating $5 | n^2 + 4m^2 + m - 6n$
Pseudo (Cat theory #1 Fan)
After simplification I get 5 | n^2 - m^2 + m - n
yep, that's exactly what you want to show
Because 4 = -1 under mod 5
so $5 | n^2 + 4m^2 + m - 6n \iff 5 | n^2 - m^2 + m - n$, right?
Pseudo (Cat theory #1 Fan)
Yes now what
do the same for $2 | n^2 + 4m^2 + m - 6n$
Pseudo (Cat theory #1 Fan)
2 | n^2 + m
Pseudo (Cat theory #1 Fan)
N^2 + M = 0 (mod 2)
yep
N^2 = -M (mod 2)
N^2 = M (mod 2)
Because -1 = 1 (mod 2)
yep
Pseudo (Cat theory #1 Fan)
this is cause $0^2 \equiv 0 \pmod 2$ and $1^2 \equiv 1 \pmod 2$
Pseudo (Cat theory #1 Fan)
Oh. I can use a remainder table
yep!
Very very nice
so that completes part a
You remember this in the back of your head or is it just plain obvious under mod 2
both
I literally didn't saw it
you can derive lots of these kinds of identities using remainder tables
here's another important one
$x^2 \equiv 0 \text{ or } 1 \pmod 3$
Pseudo (Cat theory #1 Fan)
Nice.
cause $0^2 \equiv 0 \pmod 3, 1^2 \equiv 1 \pmod 3, 2^2 \equiv 1 \pmod 3$
Pseudo (Cat theory #1 Fan)
Very interesting
i think it's case of - it's easy to verify, but hard to come up with yourself independently if you've never seen it before
We literally proved a) in a couple minutes
yep
I have seen it before, but you made me remember to keep my guard up, I literally forgot about divisibility almost as a whole
n R n <=> 10 | n^2 + 4n^2 + n - 6n
<=> 10 | 5n^2 - 5n
We might need to use the proved identity for part b)
yes that'll be helpful
in fact, you can split part b into 2 parts
i) show that $n \equiv m \pmod 2$ is an equivalence relation
Pseudo (Cat theory #1 Fan)
ii) show that $5 | n^2 - m^2 + m - n$ is an equivalence relation
Pseudo (Cat theory #1 Fan)
Reflexivity is shown easily because modular equivalence preserves commutativity
Is hard
@gentle zephyr Has your question been resolved?
@gentle zephyr Has your question been resolved?
bro is this even math 😭
It's deep math 
how deep 🙂
yes
What are you stuck on

@gentle zephyr Has your question been resolved?
<@&268886789983436800> troll
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,rccw
you'll probably need to rotate them yourself, since the last image is not the one that needs rotating.
troll
did OP get banned?
Where's the message delete thing
OP has left the server
and yeah that.
.close
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Well it is what it is
is the bot now capable of sustaining help channels without initial messages?
actually wrong place to ask, sorry.
Nah it's fine to ask lol
I don't think so
I think I'd find out if such a big change happened
lets test
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wha-
consider triangle BAC and what can be said about it
two tangents drawn from a single point to a circle are equal in length
why am i getting 55°..
because you should get 55 ?
fr?
if you're doubting, why not share your steps?
then helpers can see how you got it and comment on that.
yea ty
well this works as well the angle bisector is perpendicular to the chord, but yh hard way
my way was easier tho..
anyways Ill ask more questions cs i get stuck on simple probs like this
mine doesn't require any further constructions
maths is weird for me..cud be that
idk
-# yeh ask questions help me get green
Ik im a bit late but since the sum of the angles of any triangle is 180, and since we are facing an isosceles triangle, these two unknown angles will be equal, we can then say then that (x=value of the angle) : 70 + 2x = 180, so x=55
issok...ic ic
aite twin
im getting a diff ans from the one marked
.
the answer should be 2
yh answer should be 2
the radius of c2 is 4 so the diameter is 8 which is also equal to the radius of c3, and subtract that from 10 and u get the radius of c1 is 2
js say "ur reasoning was correct" frfr
ur reasoning was correct
ur reasoning was correct
this is so funny idk why
Lemme get more questions
alr
@jaunty isle @tranquil pine
am i tripping or its js the question
it ltrl says AB=4 which is named as x
yh a typo or something
they probablly switched the places of x and 4 or something like that
yep
yh
this is the easiest shi Ive ever done in my life
like related to mathd
maths*
wait until the test comes up tmr..
gl
,rccw
how strecthed that image is
idk why
so
,rccw
better
hm
so what do you think
2 pi
right
see 360 degrees correspond to 2pi
1sec let me check the formula
2 pi r * (thetha/2pi)
yh R\theta is
its unitary method i guess
what i did was so shitty..
i put r as 3 and cancelled it out w the 3 in denominator
well it matched with what was supposed to be done
mhmm
remember this from now
i dont get it
or this , where theta is in radians
what
the formula?
what is the circumference of a circle
2 pi r
lowk..
(i kind of skipped that lecture)
(and didnt bother myself learning em on my own)
hm.. nw radians is just another unit to measure angle,
360degree = 2pi radians
you should know them tbf
kk
mhm ic
mb typo 360 degree
😪
so you can see, a circle is 360 degrees
so pi=180 radians?
hmm
mm. not quite pi radians = 180 degrees
mm?
,, \pi radians = 180^\circ
cuz like
firestepper
360/2 🤷🏻♀️
ok nvm that
so in 2pir you can see that we do nothing but simply multiply r by 2pi, which is the angle subtended by the arc, a whole circle here 360 degrees
so basically what we are doing to find the arc length is multiply the give angle in radians by radius
moreover why this, is 1 radian is defined as the length of arc which is equal to its radius
hmmm
I seeee.....
my fam is excluding me wait a sec brb
diagram not to scale but image this sector, a partition of a circle of radius r, what we have in a circle are 2pi,(360) such sectors so basically by unitary method you can arrive at the result, lenght of arc = r\theta
aight gtg as well
@frozen sinew Has your question been resolved?
i'm back
np
@frozen sinew Has your question been resolved?
@frozen sinew Has your question been resolved?
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how can i find the domaine
it should be the same as the domain of log x
guys can i hop to calculus after trig
you can rewrite that log as ln(x)/ ln(1,25)
!occupied
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and the domain of ln(x) is R+*
?
ln (1,25) > 0
for leibniz
oh ok
huh
wdym
do you know what the domain of definition of a function is
wait the domaine is xer?
xer ?
I thought the question was in which domaine the function g is defined
like ]-infinite,+infinite[?
thats the question
oh
well no cause x I --> ln(x) is defined in R+*
like all positive non 0 real numbers
yes everything after 0 without 0 included
idk wtf that is but i call it R+*
so it decreases
because the a is negative
-3
derivate the function to find the variations
how
-3/(xln(1,25))
decreases
yep
it decreases in the whole interval
oh
why ]-3 ; -infinite[ ??
]infinite,-infinite[
i think you made a big confusion
what did the derivative do
g is not defined in all of R
so its decreasing in ]0,infinite[
@soft pewter Has your question been resolved?
.close
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. Reopen
for g(x) = ln(-5(x+1)) how can ifind the domaine
if g(x) = ln(x) could u tell the domain
log_e (-5x-5)?
yes that is what ur function is expanded but could u answer what i asked u first
i cant because i need the argument
what numbers are legal inputs for ln
log_e
not answering my question
any number above 0
ok
so your function is ln(-5(x+1))
what expression is passed as input to ln here?
(x+1)
no
(-5(x+1))
why equals
oh
no, not >
yes
because negative number is divided
x < 1
Does infinity use ( or [ ? @soft pewter
in french-style bracketing it uses a prongs-outward bracket
so it is correct but french-accented
also "domain" has no final e in english
I didn't know French math had it different thanks 
the variation is decreasing ]-infinite,1[
Wait, in french they use [] for infinity??
la variables
yeah but its not included
So, definition is interchanged?
]-infinite is the same as (-infinite
is this good
no
in french they say ]a, b[ for open intervals and [a, b] for closed ones
@soft pewter i already approved your answer here
lmao
i can repeat it 17 more times if you need me to
This makes more sense than english ones tbh
so ] = (
and [ = )
no but the variation
yes it's decreasing all throughout
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I am having trouble with this one:
Not only france
Where did you get this from?
hlo
How did u solve this
just addition if they are on same side and subtraction if not
dot + dot make box
and dot + box cancel
add 1 st 2 columns
dot + nothing is nothing
whats box + box finna do
box+nothing is noting
i think it might make dot based of the dot pattern
yea
I tought It was some kind of pattern 😭
i dont see how box+bow is dot
for each row the first 2 combined make the third
is usually the pattern for these
u gotta observe
its just a guess based off how dot + dot works
i was just thinging like the 2 and 3 element in the first row have box+box which dispears
is this the ans?
but thats backwards, so maybe yeah its dot
ye that is my guess
nice
This
precisely my question
i thoght i was banned or sum shi
I have to study these for my job interviews, so its prep
best of luck
are u training for quant or sum
idk what quant is, its just CS stuff
j*b
how can you say that offensive word?
idk why companies do i q stuff for coding jobs just test the actual skill
i remember reading a study and the leet correlation with development was pretty ass
All this for a job where you'd spend your time either sitting on a desk and doing stuff with no mental stimulation or doing something unrelated to your work
another here, if someone can help
oh nvm
i got it
you can try tho
options
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So I found the joint pdf of U, V but the problem now is that I dont know how to solve this integral
$$ \int_0^\infty f_{U,V}(u,v) dv = \tfrac18 \int_0^\infty v^2 e^{\frac{-v(1+ u)}{2}}dv$$
Branshi (Hints only plz)
been so long since ive solved integrals
forgot most of the techniques
mm this might be an integration by parts
if I let $s = \frac{-(1+u)}{2}$ then I get
$$ \tfrac18 \int_0^\infty v^2 e^{sv}dv$$
Branshi (Hints only plz)
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Is this right i dont have answers
,w 2cot^3 (x)+3csc^2 x-8cot x=0, 0 \leq x \leq pi
What
Yes
Your answers are rounded to the nearest tenth
Yea u have to for the exam
Also wolfram alpha usually just does tangent half angle sub because polynomials
Hence why there’s factors of 2 on the arctan
You can cut these bits out
You end up only testing one root anyway so it’s not like you’re exhaustively checking all rational roots
And the spurious = after “quadratic”
Idk what that does tbh
Wow I love rational root theorem
o ok
the book taught me that idk either
alr thanks
.close
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Let's say I have a digit number 1-9. and I have 3x3 matrix. I want to map the each digit to an element in that matrix. like number 3 points to third element of first row in 3x3 matrix. Is their way I can convert the number 1-9 into the number that gives me the position in matrix like i,j ?
