#help-39
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wait whats the goal here
is it just to simplify
you can factor out (1/(n+1)^2)
and then break it up more
?
both terms have 1/(n+1)^2, no?
yea but i want to get 2 fractions it is a part of a bigger problem
whats the whole problem
see what happens if you look at a_n+2
?
how can we find
you here?
you can call what's inside the sum b_n
you want to find sum of b_n from n=1 to inf
by simplifying you'll find that b_(n+1)=1/2 * b_n which is a geometric serie
by calculating b_1 you'll conclude that b_n=(-1)(1/2)^(n-1)
and that makes it easy to calculate sum of b_n (your question)
@bright apex got it!?
i sec
$you can call what's inside the sum b_n
you want to find sum of b_n from n=1 to inf
by simplifying you'll find that b_(n+1)=1/2 * b_n which is a geometric serie
by calculating b_1 you'll conclude that b_n=(-1)(1/2)^(n-1)$
ArsH
no I dont
ok let's do it step by step
you wrote bn?
what's bn
bn=what's inside your sum
yes exactly
k
... so it's easy to find
how
just simpfly b(n+1)
i want to find how we got the geometric series
b(n+1)=a(n+1)-2/(n+1)²
= (1/2)an + (n²-2n-1)/n²(n+1)² - 2/(n+1)²
= (1/2)an + (n²-2n-1-2n²)/n²(n+1)²
= (1/2)an - 1/n²
=(1/2)(an - 2/n²)
=(1/2)bn
so
b(n+1)=(1/2)bn
focus carefully
then
b(1)=a(1) - 2/1² = 1-2 = -1
so by definition of geometric series:
b(n)=(-1)(1/2)^(n-1)
there's no need to split the fraction
you can start from here assuming what's inside the sum is bn
then go from here
i want to learn that
i have not learned gp and sum of all terms of gp
you want to learn splitting fractions?
what do you mean by gp?
yes
geometric progression
it goes like this
(n²-2n-1)/n²(n+1)² = a/n + b/n² + c/n+1 + d/(n+1)²
but in that question we don't need to split the fraction
we call bn is a geometric progression we see:
b(n+1)=r*bn where r is the common ration
in our case we found b(n+1)=(1/2)bn so bn is a gp with r=1/2
then we can conclude that
bn=b1*(1/2)^(n-1)
can u explain this
b1=(-1)
you always split fractions like this
for example
1/(n+1)(n+3)² = a/(n+1) + b/(n+3) + c/(n+3)²
now you need to find those constents ( a b c d ..)
d/n
here
to find a:
. multiply both sides by n+1 then make n=-1 you'll directly find a
okey mention me if you need me
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idk at all how to tell, i don't know when i was supposed to learn this
@scarlet glade Has your question been resolved?
so like is the 4rth a hyperbola?
ohhh that helps a lot
the hyperbolic paraboloid doesn't have an axis tho
Yeah ig they don't include the "axis" for that one
The elliptical paraboloids, if you look at their graph, very blatantly point in a direction
Then the difference between elliptical and hyperbolic
elliptical the quadratic terms have the same sign
Like z = x²+y²
But hyperbolic paraboloid they're opposite
Like z = x²-y²
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no problem
just noticed i literally could have guessed abcde 😭
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Presumably the indexing starts at 1
They're writing n >= m because that's how convergence is shown (for all n past a certain point, which we can call m)
They could have picked any natural number for m
if you dont like choosing your m as 1 then you can also artificially choose m = 42069
Careful someone might pick a certain other number 
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ok i need help with this again so i did the cross product of the normal vector of the 2 intersecting planes and then the cross product of that vector and the normal vector of the plane that is perpendicular to the plane we are looking for but how do we find a point to make an equation for the plane
@dawn arrow Has your question been resolved?
cani get some helkp
Your working looks right except it should be <1, -4, 1> instead of <1, -5, 1> but that seems to be a typo, and you also need to find a point on the plane so you can gather an equation
You can get any point that satisfies x - z = 2 and y + 4z = 1 since the line of intersection is always on the plane
but why are we getting the point from those 2 planes that intersect
they intersect at one line
and they are separate planes
Because we want to find a point on the plane whose equation we are trying to find
And since we know the plane passes through the line of intersection, we can use any point from that line
right
doesnt this imply that we are using any point thats on these 2 planes and not just the line of intersection
this is so confusing 💔
Any point that is common with the intersection of those 2 planes yeah, but that's just entirely the line of intersection
The only(?) way to find a point characterizing the plane is to utilize the line of intersection
yep
at least the directional vector of the line of intersection
but you don't need to use that to find a point on the line
you just want one ordered triple that satisfies x - z = 2 and y + 4z = 1, you could for example set z = 0 to get x = 2 and y = 1
i guess my confusion lies in the fact that the 2 planes that intersect are their own planes and i can not grasp the idea that we can just grab any point from these 2 planes because they only intersect at one line and so grabbing just any old point from either of these 2 planes could also be at a point where the 2 planes do not intersect so how would that work
im sorry 😭
we're grabbing a point from the intersection of the two planes which will always be on the line of intersection, i.e. simultaneously solving x - z = 2 and y + 4z = 1
because the requirement for our plane is that it passes through the intersection of the two planes
i get that but how do we know that the point that we pick is specifically from the line of intersection and not a random point on either of the planes 💔
Because the intersection of the planes x - z = 2 and y + 4z = 1 is the line of intersection
The intersection of two non-parallel planes is always a line
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I realised that if I didn’t get rid of sqrt(x^2), I have +-, but otherwise I have only + if I got rid of it earlier
How do I make sure I always have options?
its because its not a positive once you take away the sqrt over x^2
sqrtx^2 = |x|
in which now |x|= 10, so x=10 & x=-10
ohhh Tyty
or
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does musical isomorphism basically turn vector fields into k forms ?
@vast berry Has your question been resolved?
Not at the same time
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In an urn there are 2 red balls and 6 white ones. Before one is drawn, one is removed from the urn without seeing it. Calculate the probability that the first ball drawn is red.
I considered 2 events A="probability of drawing a red ball" B="ball removed"
so $P(A|B)=\frac{P(A\cap B}{P(B)}=\frac{P(A)P(B|A)}{P(B)}=\frac{6/8\cdot 1/7}{1/8}=6/7$
Goofy Joe
but it's wrong
B = which ball removed ?
a random ball
the probability red is drawn depends on which ball is removed
it changes for red removed and non red removed
so should the 2 cases be treated separately?
yeah
?
P(A) = P(B_r)P(A|B_r) + P(B_w)P(A|B_w)
so 1/4?
yeah
But what difference does it make if I see the ball or not? That is, why in this case it is as if the ball was not removed?
if you know which ball you had removed you would just do P(A|ball)
but why in this case the final probability comes out as if I had not removed the ball, that is 2/8?
because the cases become balanced likely ig idk how to phrase it
um sorry but i don't have a good prob knowledge but many do
they will explain it better
but the event "a ball was removed" is independent of the event "a ball is red", why?
more i think of this it becomes that when you fix a ball being removed the sample space gets reduced but yh
there is a more theoretic explanation
but even if I remove 2 it doesn't change, why?
@green aurora Has your question been resolved?
<@&268886789983436800>
@green aurora Has your question been resolved?
why not try and generalize it and see
Given there are r red balls and w white balls, what's the probability that the first ball drawn is red, given that one ball is removed from the urn beforehand without seeing it?
,texsp $$\frac{r}{r+w}\cdot\frac{r-1}{r+w-1}+\frac{w}{r+w}\cdot\frac{r}{r+w-1}=\frac{r\left(r+w-1\right)}{\left(r+w\right)\left(r+w-1\right)}=\frac{r}{r+w}$$
Roy
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how do i simplify the fraction to look like the second image as efficiently as possible, I've tried to expand and simplify but I haven't been able to simplify it to look it
multiply top and bottom by (x-2)
Multiply the numerator and denominator by $(x-2)$
lol the sync
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Hi I'm reviewing my old practice test and don't understand the process of doing this problem it's been a while since we've done it 😭
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what's $2^{\cdot}$ ?
Idk which to take out
Ann
Omg
what's 2 to the power of "dot"
Oh that was a mistake
ok then what should go in there instead
One
right
anyway, 2^(-3x) is best kept as is
$2^{1} \cdot 2^{2x} \cdot 2^{-2}$ should be combined into a single power
Ann
Oh
can you erase the line starting with "(2^x)^-3 ...", do what i said, and stop there
Yes pls
oki
girl don't overthink it
ok, so you did not follow the instruction of "do what i said and stop there". you did not, in fact, stop there.
you jumped ahead.
...though your steps are correct
you got it down to 5x = 1 and divided by 5, so..
what's the issue exactly?
Understanding how to solve this
And I’m sorry for jumping
I rlly rhgouht ie as doing what u said
Well except the stop sort
Part
girl you got it down to literally 1 step away from the solution
even less than that
bc you basically executed the last step
I did it unconsciously though
if you were just told to solve the equation 5x=1 and that was the entire question, would you know what to do?
Something it feel like I’m solving but my Brian Isnt there
Yes
Wait no
ok then do it
yes
.
????
You said to stop tlajing w capital
where and when did i say that?
either you misunderstood me somewhere, or you are straight up imagining things i said which i never did
yo
if you were just told to solve the equation 5x=1 and that was the entire question, would you know what to do?
answer me this now. yes or no. please don't flip flop.
Hello
how r u
Yes
Ik good wby
hello and welcome to the server. #discussion is our place for chat
good i want to lock in for gcse
ok then do it
oh my bad
Ok
Uh you divide Bith side by 5
So you got 1/5 =c
X
you can just put the value in the question to recheck
@crimson haven Has your question been resolved?
@crimson haven Has your question been resolved?
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Hello, could someone check if this proof looks good please?
\begin{Definition}[Natural numbers]
The set of the \emph{natural numbers} is the set $\bN = \{1,2,3,4,5,\dots\}$.
\end{Definition}
\begin{Theorem}
Suppose $n \in \bN$, then $5 \mid (n^5 - n)$.
\end{Theorem}
\begin{proof}
Let $n \in \bN$. We proceed by induction.\\
\underline{Base Case.} The base case is when $n = 1$, and $5 \mid (1^5 - 1)$ as desired.\\
\underline{Inductive Hypothesis.} Let $k \in \bN$, and assume $5 \mid (k^5 - k)$.\\
\underline{Induction step.} We aim to prove that the result holds for $k + 1$.
That is, we wish to show that $5 \mid ((k + 1)^5 - (k + 1))$.
To do this, we begin with the expression $(k + 1)^5 - (k + 1)$:
\begin{align*}
(k + 1)^5 - (k + 1) &= k^5 + 5k^4 + 10k^3 + 10k^2 + 5k + 1 - k - 1 \\
&= k^5 - k + 5k^4 + 10k^3 + 10k^2 + 5k
\end{align*}
By the inductive hypothesis, $5 \mid (k^5 - k)$, and so, by definition of divisibility,
$k^5 - k = 5l$ for some integer $l$.
Then,
\begin{align*}
k^5 - k + 5k^4 + 10k^3 + 10k^2 + 5k &= 5l + 5(k^4 + 2k^3 + 2k^2 + k) \\
&= 5(l + k^4 + 2k^3 + 2k^2 + k)
\end{align*}
Since $k$ and $l$ are integers, so is $l + k^4 + 2k^3 + 2k^2 + k$.
Then, $(k + 1)^5 - (k + 1) = 5m$ where $m = l + k^4 + 2k^3 + 2k^2 + k$.
Thus, by the definition of divisibility, $5 \mid ((k + 1)^5 - (k + 1))$.
Therefore, by induction, $5 \mid (k^5 - k)$ for all $n \in \bN$.
\end{proof}
Mor Bras
seems fine to me
seems ok if your goal was to prove it by induction
you worked the goal to the hypothesis and you could consider working the hypothesis to the goal
it's a style difference
equally valid
This is actually quite interesting, I think it could be used to prove fermat's little theorem by binomial coefficients + induction
the statement p | n^p - n is valid for every prime btw
For sure
To work the hypothesis to the goal, you'd start with 5 | k^5 - k and have 5 | k^5 - k + 5 m for all m. Then specialize for m = 5k^4 + ... and prove 5 | (k + 1)^5 - (k + 1) by rewrites.
I feel that it's more straight forward than showing that 0 is not in the set of values modulo p and that every element in that set doesn't appear more than once
Thank you for the comments!
.close
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Let $\theta_1, \theta_2, \theta_3, \dots, \theta_n$ be $n$ angles. Let $s_r$ denote the sum of the tangents of these angles taken $r$ at a time (e.g., $s_1 = \sum \tan \theta_1$, $s_2 = \sum \tan \theta_1 \tan \theta_2$, etc.). Prove that:$$\tan(\theta_1 + \theta_2 + \dots + \theta_n) = \frac{s_1 - s_3 + s_5 - \dots}{1 - s_2 + s_4 - \dots}$$
Swastik
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Hi?
solve it
What do u need help with?
its a question from sl loney
trignometry and theory of equations and something
I have 3+ on that sry🙏😭😭😭
ok np just be safe while you can
🤩
let me put some dirt in your eyes
idk maybe try induction
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dipole
q = 5 uC
d = 3cm
therefore p = 1.5E-7 C m j
Field
k = 9E9
q = -10 uC
r = 1.323 cm -- from sqrt(2^2 - 1.5^2)
E = -5.1419E8 i
j x -i = k
but we just need magnitude so
|p*E| = 77.14 N m
but its saying wrong
any idea what I missed?
The electric field due to the dipole at the perpendicular bisector is :
Kp/r^3
It says only find the torque from the point charge right?
but it says find the torque exerted by the -10uC charge?
Ohk
Then use the formula I told for Electric field
And u have to find a dipole by each charge on 10uC
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i am a little confused, is this saying rho=0, phi=0,pi and theta=0,2pi is allowed or is not allowed here?
technically a change of variables requires an invertible transformation with invertible derivative but the text says it still works in this case by taking limits
so my i guess my question is when we integrate we are allowed to use these bounds e.g phi=0,pi and theta = 0,2pi
yes its valid and the text tells us we can use limits to prove that its valid
okay thanks
np
.solved
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... and what does amp(z) mean at all
i guess it is principal argument
show
!noai
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ok so in fact amp(z) means arg(z) only they decided to use the rarer or older word for whatever reason.
i see
anyway do you know what z and -z look like on an argand diagram
z=x+iy
-z=-x-yi
@fading ledge Has your question been resolved?
@fading ledge pick a random complex number and call it z. plot z and -z. whats the visual difference?
Rotation π clock or anticlockwise
@lilac jackal
great
Am I wrong?
that is exactly what you get by adding or subtracting pi to the argument
in other words the difference in their args is pi
thats the visual intuition for this claim
you see me say "great", not slap an ❌ react, and think you might be wrong?
So what are these cases?
in order to remain in the principal argument range you need to not cross the negative x axis in your rotation
Here
so these cases represent when the necessary rotation is half turn CW vs. half turn CCW
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whats the q
i did not understand the solution
what part of it
conjugate of re^(iθ) is re^(-iθ)
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im solving an integral but im stuck on this
!xy
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solve the integral
Uhm, A = B = 1/2?
It's just a system of linear equations
A+B=1 and 4A-4B=0
why is A+B=1 and 4A-4B=0
because you compare the coefficients on both sides?
you're doing partial fractions right
yeah
equate coefficients :p
im still lost
on the left it says x^2
on the right we have (A+B)x^2 + (4A-4B)
we can look at the lhs and see that we need an x^2 on the rhs
hence, i need to set A+B = 1 so that on the rhs i have an x^2
similarly, i can do the same thing with the 4A-4B
since there's no constant term, I can say that 4A-4B = 0
im sorry but why
wdym
lhs has x^2
so we equate and say we need an x^2 on the rhs
oh we want x^2 = x^2
and lhs is x^2 + 0 which would mean that 4A - 4B=0
and A+B=1 becasue 1*x^2 is x^2
Write the LHS as 1x^2 + 0x + 0
you want the coefficients to match in order for the equation to hold for all x, right?
this is equating coefficients you need to remember this from middle school
i was getting confused for no reason ngl
No worries we get confused by strange things sometimes
Who helps here?
.close
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You don't need to perform partial fractions
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@vestal pelican, write it as $\frac{1}{2}\int_{ }^{ }\frac{x^{2}-4+x^{2}+4}{\left(x^{2}-4\right)\left(x^{2}+4\right)}dx$
Roy
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We forced it out so we can do that to the numerator
Or else we can't get two copies of x^2
Can you show me a detailed way how u got there pls
it isn't so hard to arrive at that
\begin{align*}
&\frac{x^{2}}{\left(x^{2}-4\right)\left(x^{2}+4\right)} \
&=\frac{1}{2}\frac{2x^{2}}{\left(x^{2}-4\right)\left(x^{2}+4\right)} \
&=\frac{1}{2}\frac{x^{2}-4+x^{2}+4}{\left(x^{2}-4\right)\left(x^{2}+4\right)} \
&= \frac{1}{2}\left(\frac{1}{x^{2}-4}+\frac{1}{x^{2}+4}\right)
\end{align*}
Roy
@vestal pelican
Still confused with that 1/2
What are you exactly confused about
$\frac{1}{2}\cdot2=1$
Roy
Aha got it
Now confused with the last part how did it split and how did the numerator become 1
$\frac{\left(x^{2}-4\right)+\left(x^{2}+4\right)}{\left(x^{2}-4\right)\left(x^{2}+4\right)}=\frac{x^{2}-4}{\left(x^{2}-4\right)\left(x^{2}+4\right)}+\frac{x^{2}+4}{\left(x^{2}-4\right)\left(x^{2}+4\right)}$
Roy
Then cancel out common factors
as someone who hates partial fractions I will take any opportunity to avoid them
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I hate them too
Gawd dayum
I mean they're fine when it's not a very weird integral but this one was a pain
you can do something similar to $\frac{1}{\left(x+a\right)\left(x+b\right)}$
Roy
in this case you divide and multiply by b - a or a - b
You can do this trick everytime you'd do partial fractions, you just need to guess how to rewrite the numerator
$$\frac{1}{b-a}\frac{b-a}{\left(x+a\right)\left(x+b\right)}$$
$$=\frac{1}{b-a}\frac{\left(x+b\right)-\left(x+a\right)}{\left(x+a\right)\left(x+b\right)}$$
$$=\frac{1}{b-a}\left(\frac{1}{x+a}-\frac{1}{x-b}\right)$$
Roy
if you practice it a lot you'll get some intuition for what to divide
@vestal pelican if you've got no more questions, you can close this helpdesk with .close
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So I had an exam where I simplified the problem to the following recurrence and I dont know how I am supposed to solve this recurrence:
$ a p_{j} = b p_{j+1} + c p_{j-1}$ where $b + c = a$, but im also interested in the general case.
,tex $ ap_j = bp_{j+1} + cp_{j-1} $?
have you tried to solve the characteristic equation
k
,tex
If you have a recurrence relation
[ x_{n} + a_1 x_{n-1} + a_2 x_{n-2} + \cdots + a_k x_{n-k} = 0 ]
Then the characteristic polynomial is
[ x^n + a_1 x^{n-1} + a_2 x^{n-2} + \cdots + a_k ]
If q_1, q_2, ..., q_j are distinct roots to the characteristic polynomial P then { q_1^n, q_2^n, ..., q_j^n } is a linearly independent set of solutions to x_n
In general, for roots with multiplicities say q_1 with multiplicity m then q_1^n, nq_1^n, ..., n^(m-1) q_1^n are linearly independent solutions
This gives you a basis for the solution space and by plugging in initial conditions x_1, x_2, ..., x_k you can determine the general form for x_n
You can look up "linear homogeneous recurrence relations".
I think only some linear algebra is required to understand the proof
okay then I can manage
Sorry, the n's in the polynomial should be changed to k's
oh yeah no worries I got the idea
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i need help
?
how does this work
can someone tell me where i can find some good course explaining polar coordinates and its differentiation on youtube
i searched a lot
couldnt find
what i wanted
yes
basically
they are trying to find
force of inteaction
between the dipoles
ohh alr alr
i just always differentiate the field and multiply with the dipole
but the thing is
i wann properly
understand
the del operator
and how it works on polar coordinates
sorry my discord lagged and showed it as open 
thats alright
hmm alr alr sorry then i thought ill be able to help but havent learnt this wrt polar coordinates
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help to understand this site pls
I don't understand what the graphs on the right represent
for example now I clicked on draw card and that green square with 6.25 written on it came out, but I don't know what it means
the cards are from 1 to 10
you drew a 3 so the value of (x-mu)^2 is (3 - 5.5)^2 = 6.25
and since that's your only drawn card so far, this squared difference is the only one being averaged
eventually if you draw more cards you will see the green square going up and down a bit as it reflects the running average value of (x-5.5)^2
i think the intent is just to show that the two values converge eventually
but the axis has nothing to do with it
i suppose
the "value" axis is kinda weird
What does it mean to do E[X^2]?
i know what E[X] is
it would be the average over many attempts
if X="number of people taking their hat" , how do you calculate the variance?

"number of people taking their hat" is a bit unclear as a description
ah.
so the hats are shuffled and redistributed, and we want the variance of the number of people who get their own hat back.
there are two approaches here that i can see:
- find the pmf of X and then the mean and then finally the variance formulaically
- mess around with a sum of indicator variables for "the k'th person receives the k'th hat" and somehow get the variance from that (but keeping in mind these indicators won't be independent so there can be some difficulty)
(these are NOT steps, these are an either/or choice!!!)
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<@&286206848099549185>
Hello there
Hello\
!15m please
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!15m
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whoops sent it twice
it was me
1 only probably
Like a person can want to not answer the question, because of bais
Maybe
I'd say none
Rest are maybe not related to bias
I think none 2 only
There's probably 1 or 2 or both
The margin of error is likely not even related to systematic biases
Refusing to answer is different though?
Not related to the system
Related to the person
Who has bias
Possibly
Is there any more context for this problem
Conducted by phone or telephone?
no thats all
a phone isnt a telephone which means unrepvoive bais
Most people have phones, not telephones.
but the people had telpeohnes couldnt be contacted
I think telephone aand phone are referring to the same thing here
no they arent
Probably
These all seem like biases that would need a larger margin of error to account for
What kind of question is this?
Yeah
But maybe it is low
Hm
Does it even make sense to assign a number to correct such sources of bias? Margin of error usually only corrects sampling error
I haven't taken statistics or whatever this is yet so take what I say w/ a grain of salt
nope
I gave you the formula
Alright
Yeah, that's why I think hte answer is c, but it's been a long time since i did stats
Yeah no I'm unknowledgable here then
If we look at this, none of the parameters are related to I, II or III
It should make sense, like do you just go "Oh, people without telephones could not be in the sample, let's just randomly throw in 10% margin of error to account for that
that'd be quite random
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can some1 share with me all kinds of trigonometric formulas and advanced trigonometry like quadrants of which ratios are positive negative and maths related to it for practice as I'll also need to understand the concept of it first
This isn't a math question
Ask in #geometry-and-trigonometry or just Google any trig book
#book-recommendations probably has some
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Is this right
yes
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sec
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My professor didn't teach us how to prove this specific type of question (if...then)
I proved based on what I thought was logical
Is this correct?
it is
Ah, set theory. Unfortunately, I dont know much literature related to set theory.
i feel so
But I will take a look at what you have
Maybe I actually am a genius
Looks good to me. Though the handwriting could use some improvement
I would be lying if I said I'm working on it
Set theory is really fun math.
Its the first math I actually started enjoying
Lol thats okay me neither. Heres a pic
Man
Is English your first language
Ive tried making it more legible but I just dont have the ability.
It is!
I feel sorry for you
Same
Though I can't say anything cuz my handwriting is even worse in my main language
We should close this channel
Yeah me too. Unfortunately I just dont have the manual dexterity to write well.
Thank you!
.close
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would these not both be correct
the only number for real roots it could have are 5 3 and 1
which are all odd
it says it contains the term 8x^5
not that the leading term is 8x^5

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How can i calculate the exact value of log using a calculator that isnt log_10
Like log_3 (100)
,tex .log rules
Xavier 🌺
The last one
oh nice
#1071226369071136979 for your perusal
Huh
!original pls then
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So log_3 100 is just log 100 / log 3
Yes
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does the next page have options (3) and (4) for this question? both of the ones you gave seem impossible to conclude.
also
in the book
@fading ledge Has your question been resolved?
Yeah
ok can you show options 3 and 4
hm, so they're saying that the laurent series cuts off at some negative-power term?
"OH YES LET ME ASK IF ANN IS GONE LIKE 3 FUCKING SECONDS AFTER I PING HER AND THEN SEE HER TYPING"
that was rude and upsetting mate
the issue is not the ping
the issue is that you pinged me and then gave me no more than like 3 fucking seconds to even see the ping and respond to it
and then already concluded that i was gone
Ohh it is just ny type of saying
Gone means nothing much
Don't make it wrong
Okay let's back to the question
Yes
-infinity to -1
And 0 to infinity
so "gone" does not mean "gone"
am i to understand you thusly
ok anyway
they're saying it's holomorphic in 0 < |z| < ε (with poorly typeset epsilon)
... i guess this means that there's no essential singularity at 0
Hmm yes
Essential
i see
So??
if option 2 were incorrect then we would have nonzero coeffs on negative powers all the way down and then maybe see something resembling e^(1/z) and then i... wanna say it would not be holomorphic???
but i am honestly not 100% sure on this at all
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let A a non-empty set, how can I i prove that there's no bijection between A and pertation of A??
use a diagonal arguement
what are they
partition?
yes
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exactly
for that: have you heard of cantor's diagonal argument
can you do more details, im really looking forward
A can be potentially infinite?
This seems like a pretty difficult problem to be assigned without any hints
im not even sure how to hint at it without giving the key idea away
The trick is to assume the existence of such a bijection from A to P(A), and then use it to try to construct an element not in the image
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@feral sedge @toxic lichen @burnt helm im so sorry for the mention, but do you got any idea?
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How do i do this wth😭
Do you know how to get the number of digits using log_10 ?
No
Let’s say $\log_{10} x = y$
Then $10^y = x$
Starlord
Look at log_10 of 10, 100, 1000, etc and see the pattern
How many digits would x have depending on y’s value ?
Uh
X has one more digit than y if u use powers of 10?
Wait so
Log 4^100 =100 log 4
So about 60
And then u plus 1
so is it 61?
yes
i forgot but
for a similar type of question we had used this
https://math.stackexchange.com/a/2006181
@green meteor Has your question been resolved?
ok so i searched up yh that is how it is done
Wait
Is this correct
4^100=10^a+b where a is an integer and b is a fraction from 0-1
So log 4^100 =60 + 0.206….
So 4^100=10^60 + 10^0.206
And u have a and b
The questions says 10^b is less than 2 but it is also more than 1 cause b>0
yh
So 1<10^b<2
Make it 4^100
By times 10^60
So 10^60<4^100<2 x 10^60
And so 4^100 between 1….. and 1.999x …
so it starts with 1?
yh
How are u supposed to learn this b4 log
Wth
It went from log inequalities to these questions
ic
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Thanks
pure is wierd icl
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um?
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if you have an attempt, please share it!
well, that 3x somehow became a 3 after factoring a 3 out.
also, you can divide both sides by 3 straight away to get rid of it.
what have you corrected your work to?
one second
I took out the three
show me the revised work please 😄
can you show your corrected work?
you did not fix the first issue I pointed out.
this issue is still present.
Ohhhhhhhhhhhhhhhh
Yes
I'll let the other helpers handle this then.
what
Its still a fraction
its just completing the square
show revised work pls
Yaa
please show your corrected work.
Yes
where'd 2/3 come from?
2/3 is wroung
imo, just disregard the 3 right after you factor it out to avoid confusion
so from 3x^2 + 3x - 6 you get x^2 + x - 2
then work your way from there
Oki
in completing the square, i reccomend transposing the constant term to the other side as to avoid confusion with all other variables.
This is the real
that's one way to do it
but i dont think he knows this method
the colloquial way of doing it is transposition of the constant term to the right side then proceeding
Yaa this is Indian way
The question said to complete the square
Yaa i know
he employed factoring w/ regrouping
hold on let me actually do the problem myself
There are 4 way to slove
that method is inefficient imo
!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.
@wary tusk
Yes
i see your problem now
I am right ??
where'd this come from?
Thats from the completing square method
It says to (b/2)^2
what's b in this equation
It became 1
ah no
Can I help ?
Can I help ?
Let me correct it
you don't need to ask for permission to help so long as you aren't tossing the full solution directly, unprompted.
but also, keep in mind that others are already helping, so try not to derail the current helper

