#help-28
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from coulomb's
$\epsilon_0$ is the electric permittivity of a vacuum
cloud
it's related to the coulomb constant by the above formula
that k equals this
this is the expression for field around an infinite plane sheet no?
for now you can think of it as being an "electric constant" which relates different quantities in electricity, like the coulomb constant. it turns out that formulas are usually nicer if expressed using this constant rather than k, which is why it's usually used more outside of coulomb's law
yes but i didnt learn it the teacher kinda just threw it out like that
ah oay ty
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single handedly steam rolling me

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you'll get the hang of it
huh, I opened this? 
interesting, I don't see my message below the bot message

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hahahah tytyy
@nimble crane do you still need help?
It is done
I didn't even send the problem yet!
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,rotate
,rotate
,rotate
do you know the formation of a quadratic from the roots?
Ye isn't it x-alpha x-beta
if u and v are the roots of a quadratic then the quadratic is given by
k[x² - (u+v)x -uv], where k is a constant you can generally set as 1
Ye
so you just gotta treat (apla-beta)² and ( alpha +beta)² as your new u and v
Isn't it difference of two squares
yeah the coefficient " b" in the new expression is the difference of two squares
you'll need to find alpha and beta though by solving the given quadratic
One bracket is 25 correct
lemme check
the discriminant is negative :((
how'd u get 25
-5^2
oh i dont think you need to solve the quadratic
you just need the reaction between roots
relationship **
alpha + beta = -b/a
alpha * beta = c/a
you can find the new quadratic now
Ye equation 1 is -5 and equation 2 is 7
but you need ( alpha - beta)² so expand and try to transform it to a from you know
(a-b)² = (a+b)² - 4ab
just simply substitute now
Is it u-v because we are finding alpha-beta
no no
your u now will be (alpha-beta)²
and v will be (aplha+beta)² or vise versa
why its u-v is a different reason
it comes from the comparison of
a standard quadratic a(x-u)(x-v) with its standard form ax² + bx + c
yes this is it
Have we found aloha -beta squared
it can be easily found with this identity
are you sure 😈
So I did 4+7 instead of times 🙄
🤫
So -3
R they supposed to switch
Bc I get -38
28
Instead of -22 or 22
But how was I supposed to know say it wasn't multiple choice
the sign can sometimes change depending on which one you consider u and which one v
both of the answers would've been valid and you'd have to write both
lovely
corrected
u+v
and negative sign is there
also -uv
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Q7 I'm trying to find alpha
,rotate
@neat sentinel do you know vieta's formulas?
well, i guess this is what the chapter's on
your a is 2 tho
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Sorry really easy question but I graphed this correctly right?
I looked on Desmos and the x intercepts were ( -pi,0)
Oki tyyy
2π/2 = π
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from the graphs of 2 polar functions, how do you know which one is the inner and which one is the outer
the one that's closer to the origin is the inner function
imagine drawing a line extending straight out from the origin, then the first one you hit is the inner function, and the second one you hit is the outer function
You can also partition the area
but that line will hit the function depending on the theta
Yes
if that's the case then you have to split the integral
just like in the cartesian case
^
wdym by that
It’s typically easier to partition it when you’re given a visual graph
wdym
Take on function till it intersects the other, then continue the integration with the other function
if you get two separate sets of bounds then you have to split into two integrals with those bounds
Like here
$2\qty(\frac12\int_0^{\frac{\pi}{3}}(1+\cos(\theta))^2d\theta+\frac12\int_{\frac{\pi}{3}}^{\frac{\pi}{2}}(3\cos(\theta))^2d\theta)$
;(
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Can someone check this i am supposed to find the quadratic equation
Btw the (-2,3) is the vertex its just that my lines on the graph were off
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how do i solve this without power series? im in an introductory diff eq class
@pallid tundra Has your question been resolved?
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try using variation of parameters
https://tutorial.math.lamar.edu/classes/DE/VariationofParameters.aspx
In this section we introduce the method of variation of parameters to find particular solutions to nonhomogeneous differential equation. We give a detailed examination of the method as well as derive a formula that can be used to find particular solutions.
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Pls help
But here f' is 3
^
So you must compensate by dividing by 3
And the numerator is one
So you must make thr numerator 3 without changing the value of the integral
So make it 1/3 * integral 3/(3x+2)
OK, I need help with integrating ln, how do you do this.
I thought we just put ln|something|
How do you integrate ln?
You want to integrate ln or 1/smth
You cannot
Well, tell me like that then
How to fix it?
Also, why not?
I thought that "S1/something not raise to power dx" you integrate by ln|something not raise to power|
If you understand me!
I feel like I don't know ln anymore
The integral is ln you're not integrating ln tho
This is actually the original task
but I replaced dx with 1
is that not the same?
hmmm
It is but that's not the issue, for the integration to be ln|f(x)| you need to have it in the form f'(x)/f(x)
Do you understand this
f'(x)/f(x)
We don't have this?
derivation?
Yes
3, right?
aha
So if we put it in this form
We should make it integral 3/(3x+2)
But
We just multiplied by 3
So we need to compensate for it
By also dividing by 3
So outside of the integral multiply by 1/3
No
outside multiply by 1/3, okay, got it
The integration of 3/(3x+2) is ln|3x+2|
Its the same as writing 1 as 3*1/3
Yes
^
Ok now we integrate 3/(3x+2)
3 integrated is 3x?
Ok?
where did the 3 go
We don't integrate the 3
We integrate this as a whole
When you integrate 1/x you don't integrate the 1 correct?
What's the integration of 1/(x+3)
ln|x+3|
Ok so what's the integration of 1/(2x+1)
1/2 * ln |2x+1|
Yes
You need to make it in this form then multiply it by half
Yes
For your question you will make the numerator 3 and multiply by 1/3
So it's like you changed nothing
Because you did 3*(1/3)
Well you technically can but you don't need to
I gtg but send it and someone will check it for you
Is this ok?
@torn jolt okay, thanks for help 🙂
Is this okay?
these two last images that show theory answers
P means Area
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I have watched many videos on this and I still can remember or figure out how to solve this. I need to find the primeter of triangle SOW. I need to know a formula or a away to solve this.
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What is m
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✅
what does m mean
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How are they getting 2/11? for this example? Once again my college uses Pearson and it skips steps
they wrote $5\frac{1}{2}$ as 11/2
aerial.ace
That doesn't really explain much? If they wrote it as 11/2 why is it 2/11?
hours to complete job is 11/2 then what would be part of job done in 1 hour
Would an easier way be of thinking of it as multiplying the hours completed by 2 becuase it was done by two workers?
I don't understand your question
if it takes 11/2 hours to complete a job then in 1 hour 2/11 of the job is done
np 
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no clue how to find v'
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I don’t think I can proceed anymore, I’ll need a tip of some sort.
I’ve tried using by parts to simplify I_n+1, but to no avail
I’ve checked the validity of the given relation
I’ve checked my differentiation
I’ve tried playing with fraction reduction
Or try using the arcsin form, didn’t work
<@&286206848099549185>
Hello I can try, but I’m not sure if I’ll arrive at the answer
Ya sure, thanks
Damn, I kinda wanna ping helpers again
I still can’t figure it out
Is the question too uninteresting or what
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why doesnt the - cancel out
Which -s are you talking about
$$\textcolor{red}-\frac 17 \sum_{n = 0}^\infty \qty(\textcolor{orange}-\frac{x \textcolor{yellow}- 8}7)^n$$
King Leo
@wicked zodiac which two -s should cancel out (red/orange/blue)
Its because the orange - is being raised to the nth power. it is not always negative
On the other hand, -1/7 is merely a constant, which is always negative
Wait i didnt see your new question
Yea
$$-\frac 17 \sum_{n = 0}^\infty \qty(-\frac{x - 8}7)^n$$
$$-\frac 17 \sum_{n = 0}^\infty (-1)^n \qty(\frac{x - 8}7)^n$$
$$\frac 17 \sum_{n = 0}^\infty (-1)^{n + 1} \qty(\frac{x - 8}7)^n$$
$$\frac 17 \sum_{n = 0}^\infty (-1)^{n + 1} \frac{(x - 8)^n}{7^n}$$
$$\sum_{n = 0}^\infty (-1)^{n + 1} \frac{(x - 8)^n}{7^{n + 1}}$$
King Leo
!done
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Dont know where to go from there? I know it’s ln but them I’m stuck
Just integrate both the sides
Also is there a better way do this ;-:
Nah I'd say its fine. You just showed every step of solving ( even the cross multiplication ones ) thats why it looks long
im following a video as i do it so genetic fear of fucking up... you need make sure that dx or dy is on top correct? not as 1/dx or 1/dy
Yes
Is this correct? I really dont use e or ln a lot
wait, do you move the 1/5 over before hand?
Nice
got to say ... that ugly
@spiral viper
Oh yeah btw you forgot the + C
C times? Or C +
Oh okay see
When integrating you have a + C at the end , which we call an Arbitrary constant
So you'd say
ln|y| = 5ln|4+x| + C
Now I can rewrite 5ln|4+x| = ln|(4+x)^5|
And I can also rewrite C = ln(c)
Cuz you both are constants
Now we have a rule that ln(a) + ln(b) = ln(ab)
So here we get
ln|y| = ln|c(4+x)^5|
Or e ^ ln|y| = e^ln|c(4+x)^5|
Which further simplified gives
y = c(4+x)^5
lol
i appercate it though
🙂
i think im too smooth brain to understand
but ur epic for explaining it B)
Thanks
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im stuck on a
and im not even sure if i did aroc right either 😭
is that correct or is it (r"(10)-r"(7))/10-7
i might be overthinking
it is
do i have to justify to get points as well?
this isnt so bad then i guess im js paranoid 😭
i might need help on the next questions though
hang tight 🙏
do i justify b by saying "there is not a time t between t=0 and t=3 because r' is negative?"
i might be wrong with my answer too
what
you’re looking at plenty of times where it’s negative
wdym
lemme reread
is -6 in between -6.1 and -3.5?
BOMBOCLATT I THOUGHT IT MEANT r(t)=6 😭
yes
what theorem should you state
"there is a time t between t=0 and t=3 where r'(t)=6 because r'(t) is increasing between 0<t<3?"
mean value? (i think)
no
avg value?
list the ones you know
🤔
no
what theorem is concerned with guaranteeing a function takes on a particular value in an interval
what unit is this
searching my first semester notes
maybe unit 1 actually
Differentiability Implies Continuous
instantaneous velocity?
no
nah mate
thats all i could find 😭
IVT
ivt?
intermediate value theorem
i completely skipped it when scrolling
how would i justify this efficiently for the ap reader
"according to intermediate value theorem, f is a continuous..."
since r is twice differentiable, r’ is differentiable and therefore continuous implying that there exists a time t in the interval [0,3] such that r’(t) is between r’(0) and r’(3) or equivalently, r’(t) is between -6.1 and -5, thus since -6.1 < -6 < -5 there exists a time t such that r’(t) = -6
word it how you’d like
but mention intermediate value theorem
i should’ve said that in there
"by IVT.."
so i dont have to type out a full complex sentence right?
i mean
youll want to state the conditions necessary
r’ is differentiable
and so continuous
and explain that you can apply IVT
sure and maybe say -6.1 < -6 < -5
it’s light
im already lost
im going back to my notes
wait i thought the ap exam would be nice enough to provide the formula for cone volume 😭
they did
alright
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i found one value or gamma which is -1
original question please?
q9
then i found alpha and beta but the signs are inversed
the server locked me out of my original channel
also btw your work is quite messy with the "scribble individual numbers out" thing
if a line is mistaken, you should cross it out entirely and rewrite it correctly
ye i thought i made a different mistake and went to fix it but i was correct originally
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$\text{Prove that if } f: \mathbb{R} \to \mathbb{R} \text{ is a continuous function of order 3, then f(x) = x.}$
water beam
!help
To ask for mathematics help on this server, please open your own help channel or help thread. See #❓how-to-get-help for instructions.
Get your own channel
you don't need to put a thousand \text commands btw
you can include formulas in the middle of your message $y=x^2$ like this
Ann
anyway
I would do that but I’m outside on a phone so instead I got gpt to latex for me
what do you mean by order 3? do you mean that the composition of 3 copies of itself gives the identity?
So in the question it defined a function to be order 3 if f(f(f(x))) = x
ok so yes
what you want to prove essentially is that every real number is a fixed point for f
so perhaps try to suppose that there is a real number a which isn't a fixed point, and see what you might derive from that
in particular you will know that f(a) and f^2(a) cannot be fixed points either
how
read #❓how-to-get-help for instructions
also important is that you know f is a bijection!
so if there is a real number a where f(a) neq a then can f(a)>a and f(a)<a
Since a isn’t a fixed point it can be anywhere on the graph
"not a fixed point" means f(a) != a not anything else
O
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It's a theorem that if P(A| B) = P(A), then P(A | ¬B) = P(A). Do you happened to know the name of this theorem?
@rancid skiff Has your question been resolved?
that's just the definition of independent events
P(A | B) = P(A) implies A, B are independent
thanks :)
yeah and then there's some sort of derivation afterwards, idk
no worries
P(A and B) = P(A) P(B) , then P(A and B') = P(A) P(B')
now add the two equalities together and you get P(A) = P(A) * (P(B) + P(B')), so a valid proof would start from this and work backwards to find P(A and B')
so, um what about P(C | A¬B)=P(C |¬B), does that imply P(C | AB)=P(C |B) as well?
@rancid skiff Has your question been resolved?
<@&286206848099549185> does anyone happened to do know? :) Thanks in advance !
!showwork
Show your work, and if possible, explain where you are stuck.
To be proved: P(C | A¬B)=P(C |¬B) implies P(C | AB)=P(C |B).
I proved that
(1) P(C | A¬B)=P(C |¬B) -> P(C | ¬A¬B)=P(C |¬B)
and
(2) P(C | AB)=P(C | B) -> P(C | ¬AB)=P(C | B)
But I don't know how useful that is for proving that P(C | A¬B)=P(C |¬B) -> P(C | AB)=P(C |B)...
@rancid skiff Has your question been resolved?
@rancid skiff Has your question been resolved?
so first lets recall some basic syntactic laws (and hopefully their semantics are intuitive)
definition of conditional probability: P(X|Y) = P(XY)/P(Y)
joint probability:
P(X) P(Y) = P(XY)
complement:
P(A) - P(AB) = P(A -B)
where the -B is my shorthand for "not B"
you can prove this by bashing
for convenience of writing, im going to ignore the P( ) bits, but just know that there is a P() around each term, and we are allowed to do this joint probability means the P function distributes over multiplication
but even if you dont believe me, you can go back and rewrite it with the P() notation to double check
$$\frac{A\neg B C}{A \neg B} = \frac{\neg B C}{\neg B}$$
Cozmogrgdfschkipkhrshtensi
this is the given, the precondition
$$\frac{AC - AB C}{A - A B} = \frac{C - B C}{1-B}$$
Cozmogrgdfschkipkhrshtensi
complement
now multiply out the denominators
(AC-ABC)(1-B) = (C-BC)(A-AB)
after some rearranging you should get
P(ABC) P(B) = P(AB) P(BC)
and that can be turned into your conclusion
not sure if i made a mistake somewhere
something feels a bit off
oh ahaha i think i see it
so the statement you are trying to prove
if you can write it in the form "If f, then g"
i think the idea is that im assuming joint probability when it may not necessarily hold in general
so the missing piece i think is to show that f implies joint probability
and then joint probability implies g
mmmmm i think im close
yeah this last step seems tricky, maybe im approaching it wrong
damn i thought i had it
sorry
@rancid skiff Has your question been resolved?
thanks for your thoughts!!!!
very much appreciate it
I ask chatgpt and they told me this
We want to analyze whether:
[
P(C \mid A, \neg B) = P(C \mid \neg B)
]
implies:
[
P(C \mid A, B) = P(C \mid B).
]
Step 1: Using the Law of Total Probability
We express ( P(C \mid A) ) using the law of total probability:
[
P(C \mid A) = P(C \mid A, B) P(B \mid A) + P(C \mid A, \neg B) P(\neg B \mid A).
]
By assumption,
[
P(C \mid A, \neg B) = P(C \mid \neg B),
]
so substituting this into the equation,
[
P(C \mid A) = P(C \mid A, B) P(B \mid A) + P(C \mid \neg B) P(\neg B \mid A).
]
Similarly, applying the law of total probability to ( P(C) ):
[
P(C) = P(C \mid B) P(B) + P(C \mid \neg B) P(\neg B).
]
If we assume that ( P(C \mid A) = P(C) ) (which is a necessary assumption for full independence),
[
P(C \mid A, B) P(B \mid A) + P(C \mid \neg B) P(\neg B \mid A) = P(C \mid B) P(B) + P(C \mid \neg B) P(\neg B).
]
Since we are given ( P(C \mid A, \neg B) = P(C \mid \neg B) ), this condition alone does not necessarily force ( P(C \mid A, B) = P(C \mid B) ).
To conclude ( P(C \mid A, B) = P(C \mid B) ), we would need additional assumptions, such as independence between ( A ) and ( C ) given ( B ).
Step 2: A Counterexample
Consider a probability space where:
- ( B ) affects ( C ),
- ( A ) only influences ( C ) when ( B ) is true.
For instance, suppose:
[
P(C \mid A, \neg B) = P(C \mid \neg B) = 0.5.
]
But suppose ( A ) significantly alters ( C ) when ( B ) is true:
[
P(C \mid A, B) \neq P(C \mid B).
]
Then the assumption ( P(C \mid A, \neg B) = P(C \mid \neg B) ) holds, but the conclusion ( P(C \mid A, B) = P(C \mid B) ) does not necessarily follow.
Conclusion
$P(C \mid A, \neg B) = P(C \mid \neg B) \quad \not\Rightarrow \quad P(C \mid A, B) = P(C \mid B)$
The implication does not necessarily hold in general unless additional assumptions (such as independence or symmetry) are made.
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"but suppose A significantly alters C when B is true"
thats not particularly rigorous or formal
otherwise i think its basically saying exactly what i said
but more confusing
@rancid skiff Has your question been resolved?
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not sure what answer you're expecting
Me too
they're proofs of the established circle theorems...
you can look at a concise list of circle theorems,
you usually won't have to proof them every time when doing questions
the video shows you where they come from
learning where they come from usually makes it easier to remember
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Can I solve this problem using double identities?
probably
yeah that looks correct
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you might get a different C though
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If 4 points A(a,b) , B(x,y) , C (s,j) , D(m,n) are concyclic then what’s the formula for it
formula for what
for what? the radius? the coordinate of the center?
you cant just say "whats the formula for triangle"
Coordinate center ig
choose 3 points of your liking and find the circumcenter's coordinate
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Check please
My solution is kinda messy
btw my answer is 2x^2+72
It says to factor and to simplify
arent 2x-12 and x-6 in denominator?
(2x-12)(x-6) is not equal to 2x^2 + 72
why did you pull them up to the numerator in the answer?
Huh?
- what Ann just said
that also
wait how do i do that
?
can't do that with the (x-4)s - you'd get (x-4)^2 not 1
i think idk bro
so what do i do now
ahhh hold on lemme fix it
also you probably are not expected to re-expand stuff afterwards
(but if you do want to do it anyway, then you have to do it correctly. you messed it up)
why are you now cancelling the thing you cannot cancel, but not cancelling the thing you can cancel
which can i cancel
you can cancel out a factor on the top with an identical factor on the bottom
the key thing is that one of them has to be on the top and the other on the bottom
In one fraction or
?
NEVER two on the same side
Okay
also your product of fractions might as well be one big fraction anyway
so that part does not matter
i dont see any
oh that makes the answer much neater
you just swapped out the $\divisionsymbol$ for a $\times$ between the fractions
Ann
and then you like
Uhh, I just noticed, you swapped division sign by multiplication sign, but did no other changes
^
yeah
keep change flip, yes?
wait so what do i do
you must do the flip part
Flip the second fraction
basically your factorizations seem to be correct
but your entire second column needs to be redone
erase it all and redo it from the beginning but do it properly
you still have not flipped the 2nd fraction.
again. redo the thing.
from the beginning.
do not try to edit your earlier work, it will only be confusing for you AND for us.
this also, but she's now fixed her mistakes.
So you can cancel (x-6)
so now you have $\frac{(x-4)(x+2)(x-6)(x-5)}{2(x-6)(x+2)(x-5)(x-4)}$ to follow tines' suggestion
Ann
yes
and a lot of shit cancels out don't it
yes
so what'll we be left with
careful w/ this
tines no
you spoiled it
i was asking lei
@torn jolt
bingo
okayy thankss
🎉

.close this channel and open a new one when the need arises, then
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?
repost your question once more
what do you mean by "standard form"?
5*10^-1 ?
is that the exact wording your teacher used?
1/2 is as simple as things can get
@torn jolt did your teacher write the requirement(s) down anywhere?
ok show us
I have a feeling the question was y = <that big fraction division> and therefore standard form is y = 1/2
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Hi again um I forgot to ask if my new solution is right im a bit braindead 🤕
yes if asked to round
otherwise ideally you should simplify the sqrt(4) and leave the value exact
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For this when we make the assumption of x greater than a how can we jump to the next part where they say n(x-a) greater than y
Because we are saying x greater than a not x greater than a +y/n
Limit not working here ?
have a look at theorem 1.30
I have a feeling it's going to be the archimedean principle
(and in particular, x > a means that x - a > 0)
It is but I don't get how we make the jump
But how can we reach n(x-a) greater than y from here
Because 1.14 says x is less than or equal to it
How can we flip the sign
so x-a > 0
and by the principle of archimedes, we know that we can find some n such that n(x-a) > y
right?
it's a weird way of saying "we can make numbers as big as we like"
(the whole aim here is that you're proving this by contradiction: you assume what you have isn't true, so x >= a and x != a, that forces x > a and leads you to something that is clearly crazy, so really x has to be equal to a)
and if n(x-a) > y, then x-a > y/n
(n is positive nonzero integer so we gucci)
which means x > a + y/n. for this specific value of n.
but we've assumed for every integer x above 1, that x <= a + y/n.
Wait isn't this only x greater than a
So you are saying that we assume x greater than a. Which means x-a greater than 0. Using nx greater than y where x equals x-a
Then we say this contradicts the second part of the inequality so x cannot be greater than a?
So you are saying that we assume x greater than a
yup
Which means x-a greater than 0
yup
Using nx greater than y where x equals x-a
yeah but I guess it's better to say nk > y where k = x-a, or just n(x-a) > y
Then we say this contradicts the second part of the inequality
we have reached a contradiction because we have proven "starting from the assumption x <= a + y/n for all integers >=1 n, and for x > a, we can prove that there is some n' such that x > a + y/n'"
both of these cannot be true
our assumption has led us to deduce nonsense. a contradiction
because our assumption includes "a <= x", we don't even need to write out the case for that. "if x < a, then contradiction immediately" is just unnecessary
Wait im losing you at the end how does we prove that just x is greater than a+y/n
so can we start at "we know there exists n' such that n'(x-a) > y"
I want to use n' to make it clear this is a specific value of n'
we would!
and the archimedean property/I.30 says that n' is a positive (>0) integer
so we only actually need greater or equal to 1
and rearrange the inequality
n'(x-a) > y
x-a > y/n' (this does not need sign switching because n' is positive)
x > a + y/n'
Two questions I'm confused how this connects to our original thought where we started with x greater than a. And also by saying n' greater than 1 aren't we already contradicting our boundaries for the inequality
'Two questions I'm confused how this connects to our original thought where we started with x greater than a'
we are breaking down the cases of what x can be relative to a into 3 cases: less than, equal, or greater than
less than doesn't make sense so we can ignore that case
if we can prove that greater than doesn't make sense either, then the only remaining option is x=a
Ok
' And also by saying n' greater than 1 aren't we already contradicting our boundaries for the inequality'
this is why I wanted to use n' - it's not the same as the n in the original theorem. the n in the original theorem is any integer n such that n >= 1
which, of course, must include the specific n'
right? 🙂
if the question says for all of something, then finding one case when it doesn't is good enough to prove it's a contradiction
Wait I'm confused on this so your saying if it says for all n less than equal to 1 then finding one case where n is one of those values and it contradicts any part of the inequality of enough to contradict our original statement
if we had some other theorem that said "blah blah blah, for all n <= 1, then something is true" and we could prove that when n = -3 it isn't true, then we've got a contradiction
yep
So is this our contradiction
we can find some n that makes this inequality true
Just making sure this is the n less than or equal to 1
it exists. it doesn't matter what it is, but we do know it is >= 1 and an integer
(we know it is >= 1 and an integer, because that's what the archimedean principle tells us)
Wait so for that we use a different n
yeah, they are shortcutting a bit
Wait but then it doesn't apply to our inequality?
I would write it in full:
...there is a positive integer k satisfying k(x-a) > y. we can rearrange this into there is a positive integer k such that x > a + y/k because k is a positive integer, it must be >= 1.
(and then the bit that may click for you)
by our assumption of I.14, every integer n >= 1 satisfies <condition>. however it is not true for the case n = k
therefore contradiction, and x cannot be greater than a. the only remaining case must be that x = a
Wait could you explain again where we got this condition for k
theorem I.30 says, probably "for all real numbers x and y, x > 0, there exists a positive integer k such that kx > y"
aka no matter how big y is, and how small (but positive) x is, you can multiply x by something to make it bigger than y
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Can someone help me with bounds on problem 25
?
,w solution set to r^2=r^2
I would probably sketch the curves
ok
I don't completely trust the bounds although it's not unreasonable what you did
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Hello
Is there a name for a therorum that says the maximum value of some set of positiove reals contrstained to be a certain sum, can be maximized if they are all equal
isn't it the opposite? if you make them equal, you minimize the maximum
sum = 4
x1 = 1
2x = 3
product = 3
x1=2
x2=2
product = 4
4>3
there was nothing about product
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Hi I’m new to this server, I’m trying to study for the tsi with the accuplacer practice tests but I’d like to know what type of problem this is so I can practice solving it. Like what steps do I take and etc.
this is an arithmetic problem
you might see the acronym PEMDAS thrown around to describe the order in which the operations are to be done
this one in particular involves negative numbers and decimals as well
do you know how to add, subtract and multiply?
Yes
can you tell me?
Parenthesis exponent multiplication division add subtract
ok
so, in your expression:
-14 - 8 * 0.5 + 0.75
you've got a subtraction, a multiplication, and an addition.
according to the priority order you just spelled out, which has to be done first?
Multiply?
yes
so you got this down to:
-14 - 4 + 0.75
now one important thing about PEMDAS that trips people up:
addition and subtraction are on the same tier. despite the A coming first in the acronym, it does not hold higher priority than subtraction.
so our thing now has only additions and subtractions, and you do these left to right.
do you understand how to proceed now?
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<@&268886789983436800>
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yes it was a server invite to a nsfw
There should be a bot that mutes server invites
There is
Nah there are non-scam invites I’ve sent
Let it stay
Thats why it got rekt that fast
It makes the difference dw
?
Between scam and not scam
Oh it auto mutes only if the server is a scam?
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Hey can someone help me with this
What's the bigger inside angle either in
regular hexagon
or in a octagon
regular one
Think about it
If sides get bigger does degree get bigger or no?
Triangle versus quadrilateral
yes
So then the octagon is bigger?
Because it is in between two sides
Not really on "edge"
With?
Thats it
Finding zeroes?
@terse dove Has your question been resolved?
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What does it mean when it says "f is the principal branch"


hello?