#help-36
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Ok so I choose the u of log (t-1)
Now the integral that I obtain is $\int_{\log(c-1)}^{\log(x-1)} \frac{e^{2e^u+2}e^u}{u}du$
BigBen
wait so u = log(t-1)
Yes
It seemed to be the only way to have t in the denominator
Oh wait
I've been confusing myself
Let me work on the sub again then
The options seem to be u =t-1 and u= 1/t-1 but both don't seem to lead anywhere
why not the first one
Well our bounds are off and the integrand is off
don't worry about the bounds yet
let's just focus on integrand
what is "off" about the integrand?
Well to match c) we want e^u. We on the other hand have e^2u+2
ok
well, first of all, e^(2u+2) = e^(2u)e^2
so, up to a constant, it's just e^(2u)/u, right
You took the constant out?
Ye I see that but I didn't go past that since c didn't have that
Rafilouyear2026
Let me see what t=2u leads to
Also why question marks for the bounds? We know the bounda
well Idk you didn't give them to me after substitution u = t-1, so I'm leaving it to you to fill them in
t=2u will get us the correct integrand
Oh ok. There just c-1 and x-1
So our integral right now is $e^2\int_{\log(2)}^{2x-2} \frac{ e^t}{t} dt$
not accounting for constants in front, yes
Oh wait right
BigBen
Hmm. I just need to fix the upper bound now. But I cant make a sub since that would ruin our integrand. Does that mean that e^2 will play a role in correcting our upper bound?
Rafilouyear2026
or rather, to not confuse with this x here
you know exactly what $\int_{\log 2}^{\log X}\frac{e^t}{t}dt$ is for ALL $X$
Rafilouyear2026
so...
we just need to find a correct X
such that the upper bound, 2x-2
becomes log(X)
Oh. e^2x-2
Wait
Oh just algebra. x= (2+logx)/2
But who says we are allowed to choose our x in such a fashion?
huh
x and X are different
you had it earlier
log(X) = 2x-2
so X = e^(2x-2)
I specifically called it X so you wouldn't confuse it with x
Why could I not just say this?
Aren't both of them choosing a specific x and X
uh, no?
The small x you're working with has been arbitrarily fixed at the beginning
so you can't change it in any kind
Isn't the same with big X?
No because 28c has already been proved
so you know, that for ANY x >= 2, that the integral [...] equals Li(x)
so you're allowed to plug in any value you want
you can change the name of the variable if you want to
so you know, that for ANY s >= 2, that the integral [...] equals Li(s)
now, you can apply it to a specific value, for example s = e^(2x-2), with the fixed x from question d
and would you look at that
this is now e^2 Li(s), with s = ...
Ok I see c) is for any X and we just choose one. The one we choose has another x that is chosen but not given explicitly.
Thank you for the help
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How was a≤c+3 derived?
$\mathrm{gcd}(b,c) \le c$ right?
Yes
Annie Maqionde
Ok I get it
its given $a = \mathrm{gcd}(b,c) + 3$
Annie Maqionde
Yes
from there you get it
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Can someone help me with this question. It is related to Arcs
Hint : ||try finding the radius with the pythagorean theorem||
square root 8^2 + 5^2 = 9.43
r=9.43
multiplexer
Hold up you meant BOA = 32°?
BOC = 32 degrees
and hten i subtracted 180 to find BOQ right?
So BOQ = 148 degrees?
and then i can finmd the arc legnth of the whole PQ which is 29.63
and find the arc length of BQ now becuase i have the radius and degree
and i subtracted the arc length of BQ with PQ to find PB
ehh not really, i was thinking BOQ = BOA + AOQ
hm im kidna confused
after i fidn the radius
I find the angle of BOQ right
then after i fidn the angle of BOQ i find the arc length og BQ
and subtract that with hte arc length of PQ
which will result in just the length oif PB
np
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<@&268886789983436800>
<@&268886789983436800>
sniped /j
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Renato
What have you tried
The left direction is easy, just set B=Y
Proof: f(f^-1(B)) = B <=> f surjective
Proof1: f surjective => f(f^-1(B)) = B
(subseteq)
y in f(f^-1(B))
=> there exists some x in f^-1(B) such that y = f(x)
=> there exists some x in X such that y in B
(supseteq)
y in B
=> y in Y
Because f : X -> Y surjective
DEF: forall y in Y, there exists some x in X such that f(x) = y
=> there exists x in X such that y = f(x) in B
=> there exists some x in X such that f(x) in B
=> x in f^-1(B)
=>y = f(x)
=> y in f(f^-1(B))
That direction seems good. How far along are you with the other direction considering what kheer mentioned?
first of all, can we modify this direction to make it less messy?
I did this at like 5am and now that I see it I didnt explained anything and just wrote what I had on my mind
please dont hold anything back, this proof sucks
Hmmmm the argument will remain mostly unchanged. Your proof isn't bad. Maybe you can afford to jump a few steps?\
Like if $y\in f(f^{-1}(B))$, then there is $x \in f^{-1}(B)$ such that $y = f(x)$. From this you instantly have $y \in B$ since $x\in f^{-1}(B)$.\
Azyrashacorki
At the end of the day it's mostly just writing your proof more in words rather than a series of implications.
yeah exactly this is better
(In fact this direction holds regardless of whether f is surjective or not. If f^-1(B) is empty then f(f^-1(B)) is empty, so it's a subset of B.)
subseteq holds regardless of surjectivity of f but supseteq aswell you say?
Oh no sorry I meant like the first inclusion $f(f^{-1}(B)) \subseteq B$.
Azyrashacorki
because in supseteq i did use that f is surjective
Yeah that's what I mean
dont know how to start
For the other direction you mean?
for the direction f surjective <= f(f^-1(B))
Okok
Well as Kheer suggested, since f(f^-1(B)) = B holds for all subsets B of Y, try to see what happens if you take B = Y.
This gives you some equality between sets, so you may use it to show that f is surjective.
B = Y is just one case of when B subseteq Y
it does not prove the general case
Your claim is $(\forall B \subseteq Y. f(f^{-1}(B)) = B.) \implies (f \text{ is surjective}.)$
Azyrashacorki
So in your premise you're assuming that $f(f^{-1}(B)) = B$ for any $B \subseteq Y$.
Azyrashacorki
This says something useful for the case B = Y, which you can use to show surjectivity.
So try and see what your premise says about the case B=Y and then try to find a preimage for any y in Y.
again, we are not proving the general case of forall B subseteq Y when we pick B = Y
you are saying without loss of generality that if we pick B = Y the logic still holds forall B subseteq Y?
Your premise says that f(f^-1(B)) = B for any B you want. You know this to be true.
So in particular f(f^-1(B)) = B when B=Y.
There is no "without loss of generality" implicit in there.
The premise is that f(f^-1(B)) = B for ANY subset of Y.
This necessarily implies that f(f^-1(Y)) = Y.
This would be true for any subset of Y, but using this you can prove that f is surjective.
yes but if we manage to prove that f(f^-1(Y)) subseteq Y implies that f is surjective
we might still encounter some B subset Y such that B ≠ Y and that f(f^-1(B)) = B but f is not surjective
But you're not proving that f(f^-1(Y)) = Y. It's part of your premise.
You're assuming that f(f^-1(B)) = B for any subset B of Y, and you want to show that this means that f is surjective.
I dont think I follow
Say for example, we are given that the statement holds for primes p, with forall a,b in N
p | ab => (p | a or p | b)
we are not proving that this is true by showing that p = 2 works
AH, I see it now, we are not trying to prove this implication, we are trying to prove that assuming this implication holds then f is surjective
f(f^-1(Y)) = Y is just a direct result of your premise essentially
Then from this you can show that f is surjective.
forall y in Y, there exists some x in X such that f(x) in Y?
Well from $f(f^{-1}(Y)) = Y$, you can pick $y \in Y$. Then $y \in f(f^{-1}(Y))$. If you expand what it means for $y$ to be in $f(f^{-1}(Y))$, you should be able to find $x \in X$ such that $f(x) = y$.
Azyrashacorki
forall y in Y, there exists some x in X such that f(x) in Y. In particular there exists some x in X such that y = f(x), then y in f(f^-1(Y))
what are we doing here?
proving that f is surjective, that is, forall y in Y there exists some x in X such that y = f(x)
how easy from 1 to 10 is this exercise?
I have become quite acquainted with preimages and images of sets as of now, I think I can recite the definition from my memory almost instantly
this might look like a shocker but if you see the definitions, you see this is understandable
however the real challenge is using wording for the proof and omitting details that are not explictitly needed in the proof, such as making the proofs self containable as possible
I'd say it's on the easier side in the sense that if you unravel the definitions of preimages and direct images, it follows pretty much directly; you don't need to come up with a trick or something.
thanks
i will take a break perhaps now
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hwk to simplify
does a have any value or js that?
,rotate
24
what have you tried
.rccw
,rccw
What did you do after x=1??
that's one asnwer
i took out log x
no i mean after x=1
i got tht bhai mera mtlb x=1 likhne ke baad kya kiya
log x =y log 2=a
woh pura 0 hai start ka question
the log x (...)=0
ha
udhar to 0 hi rahega na
log x =0
10^0=1
yeah but log(x*...) nahi hai log(x) * .... hai
suppose base 10 hai toh log hata ne keliye 10^0 hoga na
aur 2/(logx/2 )...
Abhi log ko bhul jao
ok
a=0
b+c=0
ha
if log(x) isnt 0 then qwerty =0
lekin phir jo maine likha hai usme galat kya hua
aapne qwerty =1 likh diya
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ty
Your wlcm!
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logab=loga/logb
Please show the original problem, exactly as it was stated to you, with the entire original context. A picture or screenshot is best. If the original problem is not in English, then post it anyway! The additional context might still be helpful. Do your best to provide a translation.
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ya so I dont know how to get theta value
isnt it sqrt(x^2+y^2) for magnitude?
and arctan y/x for direction
magnitude of the resultant would be sqrt((∑x)^2+(∑y)^2)
∑x would be adding the x component of the forces
so ∑x = Gcosa + F
∑y would be adding the y component of the forces
∑y = Gsina
and the angle theta = arctan(∑y/∑x)
what
I do not understand these components
every force has an x and y component
like a diagonal line can be broken up into a horizontal and vertical component
in which if you use pythag on these 2 components you get that force
so g and f give us the force of the pink line
but why is x Gcosa + F
<@&286206848099549185>
How i may help you?
im wondering as how to find ∑x and ∑y
@sterile pebble Has your question been resolved?
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can someone help me with linear and exponential handmodeling
Do you have a specific problem in mind?
YES
this is all it says for the assignment "linear hand-modeling: justify how to obtain initial value of dataset, slope calculation from 2 points, define all variables and numbers with units;
exponential hand-modeling: justify how to obtain initial value of dataset, relative change per year calculation from 2 points, define all variables and numbers with units;"
heres the data and i need to do it by hand
please asian guy help a wasian out
@short vale Has your question been resolved?
help
@short vale Has your question been resolved?
Joy isn’t happy rn?
@short vale Has your question been resolved?
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“Let P be a point inside a circle. Three distinct chords AB, CD, and EF pass through P. If AB=CD=EF, prove that P is the center of the circle.”
Let's draw it out
i actually drew it out and i was trying to use power of a point to solve it
@dense arch Has your question been resolved?
I am not good at proof writing..
Then why do you state this one here? Is it relevant?
I dont know, could be while discussing the approaches
If you don't know then don't say random stuffs here
My bad
Chords of equal length are equidistant from the center, you can use this definition
tysm!!
!done
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can someone help me
what is 2+2=
4
TYSM
is this spam
im so happy if someone says answer
It probably is but its a gd reference
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shhh
I think so, he asked me some very silly & standard stuff
say answer
alr forget it
GNG WHAT IS ANSWER I WANNA GET FREE WIFI
<@&268886789983436800>
wym u mean?😭
Based on past interactions, I have drawn a conclusion.
sorry
hm mods not replying 
Come back tomorrow and dont troll help channels. You've done this in other channels too.
hahaha
this is a very interesting problem actually
once you see the trick, it’s actually quite beautiful, in my opinion
its closed
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guyss solve - Find the domain of the function:- |cos-1(x-4)| + 1/log(3-x)
is that an arccosine
its cos inverse
$cos^{-1}(x-4) + \frac{1}{\log{(3-x)}}$
9k
yess
well for the 1/log(3-x), x<3 since the inside has to be positive
cos^-1 can only evaluate for when the inside is between -1 and 1 so
-1__<x-4<1 => 5>x>__3
hence there is no domain or whatever it's called
no x value satisfies the solution
no real x-value satisfies the equation
or gives a real solution idk how to word it
well bro i asked for domain not the range of the function
what is the domain of arccos?
no x value satisfies the equation, it is literally x epsilon ()
{}
wait
no, i think you’re thinking of the derivative , also, that’s not the derivative of arccos assuming you are thinking of derivatives
can you tell me what a domain is?
{-1,1} i think
x!ϵ{R}
since x!ϵ{R}, then y!ϵ{R}
! indicating the opposite/negation of ϵ or just not a part of the set of real numbers or whatever i was
I feel like it'd just be the range/codomain of cos no?
that isn't even the derivative of arccos it's the derivative of arctan
yes its of tan
tell me, why would you need an equation of x to find the domain of a function of x already previously defined
am I saying this right I can't tell
yes, but you must restrict the domain of cosine.
umm i cant understand what you are saying
and all function have their own domain
i ve got a similar function of which i have already found the domain
did you got enough help
@molten zinc we should start with the basics. what is a domain? can you define it?
what is 1/(1+x^2) telling you about x when you have a function |arccos(x-4)| + 1/log(3-x) to find the domain of?
f ( x ) = cos − 1 ( 2 − | x | 4 ) + ( log e ( 3 − x ) ) like i got the domain of this function
no i wass just trying
[ − 6 , 6 ] this was the answer i got for this one
is that |x| to the power of 4 of |x| times 4 because neither are the domain of f(x) you're describing
for x__>__3, the inside of the logarithm would be nonpositive hence invalid since the inside of logarithms no matter the base have to be positive
it was for the cos part
can you show a pic of the question?
this is the finsl answer [ − 6 , 3 ) − { 2 }
f ( x ) = cos − 1 (( 2 − | x |)/ 4 ) + ( log e ( 3 − x ) ) like i got the domain of this function
you forgot something
this is the full question that i have solved and got the answer and the first question is my doubt
|x| is the absolute value of x
seems like a jee question
please help 😭
yeah mains 2024
what is your doubt then?
then??
my doubt is :- Find the domain of the function:- |cos-1(x-4)| + 1/log(3-x)
this is similar to that one
ohh
well what have you tried
a lot and also diffrentiation
Find the domain of the function:- $|\cos^{-1}(x-4)| + \frac{1}{\log(3-x)}$
how in the world does differentiattion help here?
Annie Maqionde
Show your work, and if possible, explain where you are stuck.
umm maybe u wont be able to understand my approch because i am doing it in rough
upload it anyways
indeed i can
and explain it as well
theres no solution
Please do so.
.close
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Hi everyone, I'd like to ask about the significance of Green's functions in the context of solving PDEs.
Here's what I understand, roughly speaking. An example is a Poisson problem $\nabla^2 \phi = f$ (I guess some people put a minus sign but I don't mind). To determine the solution for an arbitrary $f$, we use the Green's function to first solve it for $f = \delta (x - x_0)$ and then integrate the result times the real f over all the $x_0$.
However, I've also seen it used in the context of the heat equation to derive the heat kernel where we are setting not the inhomogeneous term but the initial condition to a Dirac delta. So I guess my question is, where does it go, and how does my Green's function give me the solution?
Cark Marney 🐢
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Is the question wrong cuz i dont think its solvable with 'different +ve int' (it is a memory based PYQ so.. high chances)
I Started with begger's method to get a starting point and then started making cases for 2 same, 3 same.. but that just didnt feel right
why not?
You normally solve these with stars and bars
whats that?? i applied beggers method.. thats what i was taught
search it up, will you?
aight
khan academy or libretext math
Maybe a different name for the same thing, I don't know beggars method
TIL they are the same thing
https://kingseducation.in/mod/book/view.php?id=290&chapterid=57
Yeah they are the same lol
Okay so you don't need cases. Consider a different variable u1 = x1 - 2
beggers method says nothing about Different +ve integers
or there was this coefficient-in-a-certain-thingy way thing, for this problem i think i'd be coeff of $x^{100}$ in (x^2+x^3...............)(x^1+.......)^3$\\
hm but i dont expect you to know this method, and correct me if im wrong.
Annie Maqionde
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this is one of the most elegant ways if you know it
i have it in my notes but yk,,, never really saw it
its important 💀
That's a useful method if you have a max and min, but with just a min, there's a much easier way
I saw this in my notes.. it is
The non negative integral solutions of x + y + z = 15 is equal to coefficient of a^15 in the expansion of
$(\sum_{i=0}^{15} a^i)^3$
Chetan???
but this too doesnt mention distinct +ve solution
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I don't understand why im wrong
You put parentheses within the parentheses.
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isnt an operation involving a row already being operated on invalid?
This is valid
Note one is happening after the other. They don't happen "at the same time"
@rough nimbus Has your question been resolved?
the point of doing row operations is that they dont effect certain properties of the matrix (i.e. the null space) so any number of these operations is perfectly valid as long as the first one is
youre talking about the using the new value of R2 when operating R3 right? but R3 in next step is oly possible using the value of R2 before it was operated on
can you elaborate a bit on that please?
That’s fine
You can think of it as R3 -> R3 - (R2 - R1)
but it doesnt equate to the elements we are getting in the det? (check R3 in 2nd step of the attached pic, it does not form after R3 -> R3 -(R2 - R1))
ah sorry
just do the 2nd one first
do R3 -> R3 - R2
and then do the R2 -> ... line
Oh yess we can also think that way about it
that makes sense, thanks for the help
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fastest help channel

I need this power
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For his proof of theorem 7.2 how can he say that a,b,c are equations involving two polynomials of the same degree. For b and c the Taylor polynomials are not of the same degree
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I agree, they are not necessarily polynomials of the same degree, but they are polynomials of degree at most n, n-1, or n+1 respectively
Ok so what he said is just wrong
take f(x) = x for instance lol
I'm not seeing the connection?
let me make sure I understand, is $T_n(f)=\sum_{k=0}^n\frac{f^{(k)}(a)}{k!}(x-a)^k$?
Flip
Yes
ok great, so each T_n(f) is at most an n-degree polynomial
Why at most? It is a n degree polynomial?
because the nth term may be 0 itself
the nth term of the summation in T_n(f) involves taking the nth derivative of f
but if f is a polynomial of degree less than n (like a monic polynomial), then that nth derivative is 0
But isn't f always a polynomial of degree n
But an exponential is not a polynomial
Ok. But the taylor polyomial will always be of degree n if the nth derivate of f is not 0
yes
Ok so going back to the question we have Taylor polynomials of n,n+1 and n-1. Clearly they are not the same
(a) seems fair I think, right?
you're adding two <= n-degree polynomials, whose sum is another <= n-degree polynomial
Yes that is but the other two I cant see. And the way he states it makes it seem as though we are applying it for a,b,c. I was worried that I was missing soemthing
the left-hand side of (b) is the derivative of an <= n-degree polynomial, which is an <= n-1 - degree polynomial
Is it really ≤n since we define it as strictly n
Ok so then I am correct in stating his statement doesn't hold for b and c
the inequality only covers the instance where the functions have n'th derivative 0 at x=0 or x=a for whatever agreed-upon a
but like, even in statement (a), f = -g and c1 = c2 could be the case
you might see what they're trying to go for if you tried to prove it yourself
still defending the vibe of their claim, the degree in question may not be the same for each of the three statements
like if you're saying the claim is false because n-1 is not the same as n, then you could be missing the idea
in (a), both sides are degree at most n
in (b), " " at most n-1
in (c), " " at most n+1
in either of the three statements, both sides of their respective equation involve polynomial expressions whose degree is bounded by a common number
So your saying it is the same after you apply the integration operator and the differniation operator
I think I would casually say that this theorem is asserting that T_n is an operator that plays well with addition, differentiation, and integration
Yes I understand that but could his statement be explained then on the left side we have the deirvative of a taylor polynomial of degree ≤n. This of degree ≤n+1 which is the same degree for the one on the right and likewise for the integration
just to be clear, I don't think the proof in the textbook is satisfactory, it only indicates what the idea is
it's easier to just use the definition of T_n in all three statements
Ok so for the first proof I was thinking setting up the polynomial as a sum and simply using the properties of the sums
yes
The other two proofs I don't know how to formulate rigorously
So let's say for b. We have a deirvative of a sum. It can be shown by induction that this is equal to the sum of the deirvative
So then we are applying the deirvative to each term in the sum and by the power rule this should lower each term by 1. But this to me seems more like an explanation than a rigorous proof.
What could I do about that?
I would address the right-hand side
the k'th term in the sum T_(n-1)(f') instructs us to take k derivatives of f'
and crucially this is the same as taking k+1 derivatives of f
that at least motivates the next step in your proof starting from the left-hand side
Why are you calling it the k'th term is it not the n-1 term?
I'm not seeing it
I'm saying when you write T_n(f) as a sum
like you have
\begin{align*}
\frac{\mathrm d}{\mathrm dx}T_n(f)&=\frac{\mathrm d}{\mathrm dx}\sum_{k=0}^n\frac{f^{(k)}(a)}{k!}(x-a)^k\
&=\sum_{k=0}^n\frac{\mathrm d}{\mathrm dx}\frac{f^{(k)}(a)}{k!}(x-a)^k\
&=\ldots
\end{align*}
Flip
Yes I see this. And then we want this to be a sum of n-1 terms where the constant is the same * k(x-a)^k-1.
it should actually be n terms, but you can write it as n+1 terms all the same
you just realize that the first term is 0 and remove it from consideration
$\sum_{k=0}^n\frac{\mathrm d}{\mathrm dx}\frac{f^{(k)}(a)}{k!}(x-a)^k=\frac{\mathrm d}{\mathrm dx}\left(f(a)\right)+\sum_{k=1}^n\frac{\mathrm d}{\mathrm dx}\frac{f^{(k)}(a)}{k!}(x-a)^k=\sum_{k=1}^n\frac{\mathrm d}{\mathrm dx}\frac{f^{(k)}(a)}{k!}(x-a)^k$
Flip
because d/dx(f(a)) = 0
then you fiddle with indices
after taking your derivatives as you mentioned
I see you say j=k-1 and we obtain everything we want in j and simple say k=j
I like to write reindexing like that in my notes as $k\mapsto k-1$ so that $1\mapsto 0$ and $n\mapsto n-1$
Flip
you are completely right though
Wait for integration shouldn't our sum start from 1?. Since there will be no constant
no, I'm pretty sure we still must faithfully apply the definitions where they go
We are going to have $\sum_{k=0}^{n+1} \int \frac{ f^{(k)}(a)}{k!} (x-a)^k$
that seems fine
maybe I'm just not seeing the problem because I haven't gone through the motions myself
So each term will gain an (x-a)
Oh so my sum is wrong
at least if it's meant to be read as the left side
BigBen
I feel like I keep seeing it wrong sorry
$T_{n+1}(g)=T_{n+1}\left(\int_0^xf(t)\mathrm dt\right)=\sum_{k=0}^{n+1}\frac1{k!}\left[\frac{\mathrm d^k}{\mathrm dx^k}\int_0^xf(t)\mathrm dt\right]_{x=a}(x-a)^k$
Ok so I take the integral out and I have it for T_n+1
Why are you taking the derivative?
because $g^{(k)}(a)=\frac{\mathrm d^k}{\mathrm dx^k}(g(x))|_{x=a}$ with $g(x)=\int_0^xf(t)\mathrm dt$
that looks a little better to me
Doesn't the differentian cancel the integral
kinda, the first one does this but not when k=0
Ok makes sense. So for all but k= 0 since it is no derivative.
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yo I'm stuck
nah your antiderivative is wrong
$\int \frac{dx}{x} = \ln |x| + C$ yes but not $\int \frac{dx}{f(x)} = \ln |f(x)| + C$
oh
riemann
riemann
then power rule for integrals
¿Buenas tardes quisiera pregunta,como se desarrolla exactamente los vectores cuando hablamos de fuerza de newtons?
Oye, amigo, tienes que crear tu propio canal
Dirígete a #❓how-to-get-help para obtener ayuda; busca los canales llamados «help» que no tengan ningún nombre junto a ellos.
a es que soy nuevo gracias👍
,w int 0 to 1 x/sqrt(x^2 + 1)
No te preocupes hermano!! Todo bien 👊
correct
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hi i have a problem:
(67f)^3 = c mod n
with f^3 < n
f is the unknown
to solve this i thought of applying the inverse moduli of 67^3 both sides:
which would give:
f^3 = cinv(67^3) mod n
and since f^3 < n
f^3 would be equal to c*inv(67^3)
but the issue is that last is not a perfect cube
where is the mistake in my reasoning
because you needed c to be a cube mod n (a cubic residue) in the first place
(67f)^3 = c mod n means c is equal to a cube mod n
then if d is a cubic root of c mod n, ie d^3 = c mod n
f is d*inv(67)
you can't tell much more than that if you don't give a n and a c
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- Prove that for all $n \in \mathbb{N}$ it holds that $36 \mid 19^n - 18n^2 - 1$.
Renato
6 | 36 => 6 | 19^n - 18n^2 - 1
19^n - 18n^2 - 1 = 1^n - 0 - 1 = 0 (mod 6)
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I’m not sure if I got the graphing correct I also don’t know how to find the b value

spam vs skill
wait
i think
2pie • b = period
Can u make it blurrier
LOLOLOL
Just for u baby
SON😭😭😭😭😭😭😭😭😭😭
What is the question? what are you graphing?
Bro you can’t find ANY value on this 😭😭😭😭😭😭😭
!original
Please show the original problem, exactly as it was stated to you, with the entire original context. A picture or screenshot is best. If the original problem is not in English, then post it anyway! The additional context might still be helpful. Do your best to provide a translation.
!redir
This channel is only for on-topic discussion. Please take casual conversation to #discussion or #chill.
I’m graphing a cos
Idk the name
Post the original question, please.
With full context
If it's not in english, translate
Annie Maqionde
yes
Yes
If I were you I'd take 5 values of $\theta$ and find the corresponding values of $y$, make a table, then plot.
Annie Maqionde
5 cuz it says so in the question
wait lemme try to make a table
We will from now on let OP answer
Since this is not your help channel
Please don't interrupt
It doesn't matter.
Required person will copy from the OP later.
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how do I start
Well I may give some hint on (ii)
Try to show something is congruent
hint semicircle subtends right angle
as in b?
yes. sorry
so here
I joined OQ
so the angle at the centre is twice the angle on the circumference
which qs? a, b or c?
for b
no try to show QRP and SRP are congruent
how tho
radius and common side matches
look at the angles
so QR is the bisector
so angle PQO and SQO equal
meaning POR and SOR too
that’s it right?
observe RQP=RSP = 90 degrees
yea
yes
Yeah
yes
ok
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can someone explain
where the minus comes from
what i did was
sechy=x/2
differentiate with respect to x
dy/dx(sechy multiplied tanhy) = 1/2
you’re missing a - and also the derivative of x/2 is not x/2
respect to y
mb typo
it is function of x in terms of y
but where is the minus coming from
if u derive sec u get secxtanx
i dont see why it doesnt stay the same cos of the hyperbolic function
dont you have to implict diff if you are doing that?
i know abt the one rule
refer to the exponential definition
but like most the time it randomly doesnt apply
sec and sech aren’t the same function
yh
but most the derivatives of the normal function are the same
as its hyperbolic
instead of just assuming the same rules from trig work for hyperbolic just use the exponential definition and figure it out yourself
i dont have that much time in an exam
this is a past paper dw
but still
or yea just do it once
and you will remember it everytime a question comes up
yh fair point
this acc very useful
thank you
but do any of you abt the one rule
where if u have sinh^2x u put a negative in front
still prove for yourself where that negative comes from
its like why it goes from cos^2+sin^2=1 becomes cosh^2-sinh^2=1
because it is hyperbolic functions
not the
regular
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What do you call these things in the calculator? Referring to "x10²⁷." There are some cases where that's also a negative (e.g. x10^-03). What actually are they and how do they work?
Do they have a specific term or name?
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Hi How do you do this no calc?
Integrals without calc? 🤔
yeah, if you do an integral that was calc
It's indefinite integral anyways
They mean calculator but its indefinite anyways
They might mean without a calculator
Elderly won't get this slang
calculators can;t do this as whipl said
Wolfram Alpha is a calculator that can solve it, im assuming there will be various other ones that can as well
$\sin^2(x) + \cos^2(x) = 1$
Then it can be splitted into two smaller integrals, smart
@potent nova Has your question been resolved?
ah okay lm try it
You might want to react to the bot
@potent nova Has your question been resolved?
??
ngl i lurked theough the server and found ur integral and ive been trying stuff for a while but i cant get anywhere either 💀💀🥀
if only it were from 0 to π/2...
if sin^2 = 1- cos^2 then?
$(1-\cos(x)^2)\cdot \cos(x)^4$
This should help
Minλ
@potent nova @potent nova
ik the solution (or one ig) from a calculator app i got and gaw damn
!nosols 😭
As a helper, please do not give out answers that could be copied as a homework solution. Have the student work through the problem themselves and guide them along the way.
its a lengthy integral anyways
How in the world did you get that
im sorry
You are done in like 6 steps, I don't know what's the problem
Your sorry by umamusume have been forgiven because i like that game
hell yeah 🔥🔥🔥
But anyways by expanding the cosines and split it out it wont be that bad
i mean if u go from sin²cos⁴ to cos⁴-cos⁶ and manip a bit u end up with (sincos)²dx idk 🥀🤠
How
maybe im just making errors
Show your work
She is not OP
My skibidi blud
I dont think the question is that bad
if you are comfortable with reducing cos^6x then its not bad 
Or cos^6 =cos^4cos^2
Sure
as long as u know the formula but ive never seen it 🐌
yeah w it is just straight forwars
meisho doto?!?!?!?
uhhh u can do the funny with
sin2x=2sinxcosx => sin2x / 2=sinxcosx and squaring, and cos^2x=(cos2x+1)/2
power reduction is a formula made up by IBP followers who believe derivatives can actually be treated as fractions(they can't trust) we shan't do that sin
yeah p much
😭😭istg ive never seen it in my life until now
yes!!!! my dear baby shes the cutest
@potent nova Has your question been resolved?
What?
I meant the power reduction identity for cos^2(x)
(1+cos(2x))/2
"they can't trust"
It seems the OP has no intention of solving this anyway ...
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hi guys im really confused on how to proof by contradict its just a hard concept for me, and i was wondering if you could check if my answer is right and i didnt know whether to say " asuume that m^2 is not divisible by 2 or that m is not divisible by 2"
the proof should start with the negation of the conclusion. The statement in question has the form
if P then Q
where P is the statement $m^2$ is divisible by 2. and Q is the statement $m$ is divisible by 2.
riemann
The negation of Q is the negation of m is divisible by 2
for proof by contradiction yes
Just negate Q alwyas
WOWWWWWW OMG
Wait let me find a new question just to test this
Sorry, what about these two?
these dont have the if P and Q so for example, the 2nd one i'll just say "assume that there are positive integers for p and q"
but for the first one i make sure that tanx - sinx < 0?
so like flip the sign orrr
how about you focus on one problem at a time and write out your "if P then Q" here
similar to what i did for you here
As in one question at a time 🤣 Yeah sorry im getting ahead of myself
Okay so, for this question, "if tanx - sin x > 0 within 0 < x < 90, then tanx - sinx > 0 within a different range?"
sorry to interrupt but i think i can solve question 16
Icl this ones hard idek wht im saying
Yes pleaseeee
ok
firstly it goes like this
note that, a perfect square when modulo 3 is either 0 or 1
4p^2 - q^2 = p^2-q^2 = 2(mod 3)
where have u got modulu 3 sorry
what do you mean
like where have u gotten that from
you consider 3 cases: x modulo 3 is 0 1 or 2
i mean my english(in math) sucks
forgive me
ok so first are we provin that there are no positive integers for 4p^2 - q^2 =25
lmao its fine 😭 im just in year 13
which is like senior year
so i dont wanna overcomplicate it
i'm 14yrs old
💀 oh damn
it's kind of basic knowledge you know
yeah i just got humbled
ok carry on thank uu
Yeahh maybe you're asian lol
Really smart
you got it right 🙂
🤣 Could tell
for this to happen, there is only one case where p^2 is divisible by 3 and q^2 is not
p^2 is divisible by 3 and 3 is prime so p is divisible by 3, which means p = 3
wait
oops
It's probably more straightforward at this level to factor 4p^2 - q^2 and consider factors of 25.
lemme rethink for a bit
Yeaaa i think it'll be simpler
oh yeah i forgot 🙃
Thank you tho logic guy
sry for overcomplicating things
Noo its ok thank u for trying anyways 🥰
So like i factor out 25 for 5 x 5
Then try to factor 4p^2 - q^2. Should be an identity you've seen before.
Yep

