#help-27
1 messages · Page 402 of 1
alr give me a moment
you can't have 0 even that would be a 4 digit number since set conatins 4 odd numbers
I think repetition is allowed here
oh ok right then
.
.
i dont think theres an error here, btw where are the questions to the answers that youve written below with pen
Additional Instructions:
For number 2
Letter
e. Find the probability of S in letter a.
f. Find the probability of P in letter b.
g. Find the probability of S union P in letter c.
h. Find the probability of S intersection P in letter d.
i don't understand these parts? S and P are sets, not events how can we calculate there probability?
i think these questions might ne wrong
what did u assume that the question meant?
And btw 1e is wrong
You included (0,0) in the favourable set
0×0 is not less than 0+0
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Well if P is any point, assume a point P on the circle that will make your calculations easy
isint that already given that p is on the circle ?
Yeah so P can be a lot of points
All P work I assume since the word "any" is used
And it's unlikely eccentricity and point both can be solved unless it's a limiting casr
My suggestion would be take the point P as (0,a) on x^2 + y^2 = a^2
i let P to be in the y axis ,
yea exactly
it didnt help
what , how ??
Draw the diagram and send
i am prolly making it wrong ,
the pt q and q' , doesnt seem to be good
Well let's just say you can prove triangles AOP and A'OP can be proved yo be congruent
yea
Generally PAP' is symmetric about y axis
And the ellipse is symmetric about y-axis too
yess
So both the intersections will be symmetric about y-axis too
So AP and A'P have the same length
So do AQ and A'Q'
So AP/AQ = A'P/A'Q'
ohh , haa
To find AQ you need to solve x/a + y/a = 1 and the ellipse equation
You probably can't
Ig in terms of a you can
1 - y^2/b^2 = (1-y/a)^2
2y/a = y^2(1/a^2 + 1/b^2)
Too lengthy ig
Could be solved tho
Welcome
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I have a linear transformation T: C_4[x] -> C_4[x]
I want to turn it into matrix representation by plugging in the basis polynomials, but I am having a hard time figuring out what those would be
could I get some help on this?
hi, for future helpers, I think it would be best if you posted your question straight up!
Well I guess if I rewrite the question.
How do I figure out what the basis for C_4[x] is?
you mean helpees?
no such thing as "the" basis
what are “those”
I mean helpers.
C_4[x] is a vector space like any other
rather "a" basis
can you cook up a basis for R_4[x] as a real vector space
I don't really understand what would constitute a basis for polynomials to be honest, how do I isolate 4 polynomials such that each one would represent 1, x. x^2, x^3, x^4
5, not 4
yes
{1, x, x^2, x^3, x^4} is in fact a perfectly serviceable basis for C_4[x] over C as well lmao
how do I write it as a polynomial though? for example p(x) = a_0 * x^0 + a_2 * x^2 etc...
write what as a polynomial
i... don't really understand what you're asking here
1 is a polynomial. x is a polynomial. x^2 is a polynomial...
so what's this "it" that you're talking about
I mean what would the polynomial x^3 for example would look like as p(x)
what would the argument for p be
x^3 is x^3 ...
if you want to be mega pedantic about it you could like... write it as 0 + 0x + 0x^2 + 1x^3 + 0x^4 but that's maximally dumb
okay, now given this polynomial how do you write it as P(...) = 0 + 0x + 0x^2 + 1x^3 + 0x^4
what would ... be here
it's all x all the way down lmao...
If you're studying linear algebra, I really hope you've previously studied prealgebra, algebra and precalculus
if you wanna use the name p for this polynomial then like
just write p(x) = x^3
but also understand that polynomials don't need to have letter names slapped on them
not inherently
i think you're overthinking something here
okay I have totally embaressed myself, i understandd how dumb the question was initially
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I have a fair understanding of liner alegbra fundamentals, so this is where I would like to be met in the following question, if possible.
Suppose i have a square matrix $A$. It is in an exponential $e^{A}$
Kurrristian
The matrix $A$ can be diagonalized: $e^{A} = e^{PDP^{-1}}$. Suppose now that I have $(e^{A})^{x}) = (e^{PDP^{-1}})^x$, where x is just some scalar
my immediate thought is, well, $PDP^{-1}$ should always commute with itself. So I could just distribute $e^{xPDP^{-1}}$
But there is the super basic definition of power, which is just multipying osmehting times itself over and over agian $(e^{PDP^{-1}})^{x} = (e^{PDP^{-1}}) (e^{PDP^{-1}}) (e^{PDP^{-1}}) (e^{PDP^{-1}})....$
Kurrristian
To be honest youre basically forced to go into the taylor series of e^x
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I don’t even know how to start this question… how do I solve?
,rccw
and you don't have a printed version of this?
cause it's kinda unreadable
$\sqrt[3]{3} \cdot 93 xz^3$
Ann
is that what it says?
thats probably times 2 cubed
let's let OP confirm
@flat jungle Has your question been resolved?
3sqrt
do you mean cube root, (which shortened would be cbrt)
3sqrt(393) means $3\cdot\sqrt{393}$
ραμOmeganato5
regardless what is the question asking you to do with this expression
@flat jungle Has your question been resolved?
read above
OverHeatVD
what is the question asking you to do?
@flat jungle Has your question been resolved?
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I need help finding y so I can find the sides. I found x and then tried finding y, but I messed up in my calculations.
there is no side with length 2y-1
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relate it with the real parts of other two of the solutions
and compare it with the sum of all solutions
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Question says,
"A rectangular container with two square sides and an open top is to have a volume of V cubic units. Find the dimensions of the container of minimum surface area. Record in terms of V."
The picture is what I have so far. Am I doing it right? (I haven't finished it yet. Wanna know if i'm on the right track)
you are on right track
GODSWORD
correct
you could have split the terms before differentiating like this. It'd be easier
ohhh is V a constant?
i think that makes a lot more sense
thanks a lot!!!
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I claim this expression:-
v(to)+∆v(to+∆t) +∆v(to+2∆t)+...+∆v(t1)
Is exactly equal to v(t1).
Why have they used ≈ in the text book.
Isn't this just vector sum ?
The approximation is not yet taken
it's not exact when \Delta t is arbitrary
as \Delta t becomes smaller and smaller (goes to zero), it becomes exact
@quartz bloom Has your question been resolved?
Can you elaborate please
Do you mean , we have to add smaller and smaller increment in v(to) , to get to v(t1) .
And unless we use that increment to be infinitesimal , we are approximating the increment
pretty much
"Pretty much"...
well
yes
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Prove
Lim(x->0) sin(kx)/kx=1
So our proffesor wants this
I showed him geometric proof, doesn't want it
Nor does he want l'hopital's rule
AND he wants it using squeeze theorem
The only "hint" he gave is
-1<=sin(kx)<=1
I'm lost
Omg u were typing all that im sorry
$$\frac{1}{2} \sin(\theta) < \frac{1}{2} \theta < \frac{1}{2} \tan(\theta)$$Dividing all parts by $\frac{1}{2} \sin(\theta)$:$$1 < \frac{\theta}{\sin(\theta)} < \frac{1}{\cos(\theta)}$$Taking the reciprocal (which reverses the inequalities):$$\cos(\theta) < \frac{\sin(\theta)}{\theta} < 1$$As $\theta \to 0$, we know $\cos(0) = 1$. By the Squeeze Theorem, $\frac{\sin(\theta)}{\theta}$ must also approach $1$.
Ajay
$-1 \leq \sin(kx) \leq 1$ is too loose
Ajay
That's the hint he gave
But how do we know that 1/2 sinx is less than x/2
graph
Doesn't want it
Ik it to be true
Here's the proof I showed to him
Consider a unit circle with an angle $\theta$ (in radians). For a small positive angle $\theta$, we can compare three areas:
-
Area of the Inner Triangle: $\frac{1}{2}(1)(1)\sin(\theta) = \frac{1}{2} \sin(\theta)$.
-
Area of the Circular Sector: $\frac{1}{2}r^2\theta = \frac{1}{2} \theta$
-
Area of the Outer Right Triangle: $\frac{1}{2}(1)\tan(\theta) = \frac{1}{2} \tan(\theta)$
Ajay
No thoughts?
Yes but he wants another method to prove
For some reason
What method?
So not even a little geometry is allowed?
His hint doesn't work at all
Because taking Limit[Divide[1,kx],x->0] does not exist. From the left is gives -infinity and from the right infinity. So you cannot apply the squeeze theorem
@tepid garden Has your question been resolved?
Exactly
I tried telling him that
And added that of it's x-> infinity then it's equal to 0 and it's easy to prove that using squeeze theorem
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hi im currently using matlab for the first time and am rather stuck with something if anyone has experience using it would appreciate some help thank you
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is this doable using complex analysis
or any other method really
$2∫_0^∞\f{√{1+x}}{\l(x^2+2x\r)^{3/4}}\di x$
2x
Infinium³
why the IV quadrant?
you can just keep it in the first one
and i think it'll be easier if you do a full quartercircle instead of the smaller one you have
something like this
this is absolutely impossible isn't it

oh I just saw your msg mb
yeah that looks scary
ohhh actually lemme try it
😭😭😭😭
what's the context of the question
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.
my weird attempt of trying to solve the integral for the lemniscate constant
it's equal to half of B(1/4;1/2) but i'm nowhere near that right now
i don't even see how i'd get it using complex analysis but i'm trying cuz why not
@deft flower Has your question been resolved?
I don't see how I can solve it <@&286206848099549185>
Diddy?
yes 😔
@deft flower Has your question been resolved?
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help
i don't understand how the answer for d is the answer for d
i have the answer btw just don't get how to get there
you don't know how the answer for d is the answer for d?
I don't see the answer for d being shown here though. that box seems to be the answer for c.
can you tell me the answer for d
sry it's like im testing u
but just so u know the answer and then explain it rather than basing an explanation off of the answer i give you
here's the whole picture with answers if needed
I was just confused about the statement and hoped to establish more context for future helpers, sorry.
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Following up from my previous post, I've written out an attempt at a proof, but something feels wrong. In particular, i feel like the last page uses faulty reasoning, and that i ought to use some sort of epsilon prime trick to do it properly.
that's some handwriting
Not that bad tbh
the only issue is you're still using limit laws
When you handle the terms 1/n^2, 3/n, ... separately, you are secretely using laws about limit of sums, products...
You'll probably have to actually pick your N manually
I see, how should we go about doing that?
Im sorry 😭 ive never had good handwriting...
You'll need to bound that original absolute value thingy
So I'd start by simplifying it as much as possible
and manually subtracting the 1/2 (bring it to common denominator)
This is what I initially tried, but the furthest ive gotten is simplifying it to (3n+9)/|4n^2 - 6n - 14|
Couldnt figure out how to simplify from there
Okay, this is quite good
The cool thing is that we only need it to be < epsilon, we dont care about what it actually equals
So if we somehow "round it up" and it's still < epsilon, we dont really care, it gets the job done
So you just need to "round it up" (find some upper bound), which is simple enough so that you can work with it
and it cant be a trivial upper bound, the upper bound itself must still -> 0
I also tried doing this, but couldnt find anything that was actually an upper bound
I see, well, it's a fraction
so we will want to make the numerator slightly bigger and the denominator lower
Another good thing is that we dont care about how it starts, but we just need the upper bound to eventually overgrow it (so if we pick large enough N, the upper bound should overgrow it)
so e.g. we could bound 3n + 9 by 4n, because if we pick N >= 9, which we can, it will be an upper bound
and to ensure that we pick N >= 9, we will pick N = max(9, whatever we get later on)
Do you understand why we can do this?
I do, and i also see (i think?) that if we pick N >= 9, then the denominator can be erased too, since |4n^2 - 6n - 14| > 1 for n >= 9, leaving us with the upper bound just being 4n
Yeah, sure, 4n is an upper bound
but that upper bound doesnt tend to 0 anymore
so we cant really pick N which makes 4n as close to 0 as we need
Oh true
We need a better upper bound, we need the upper bound to still tend to 0
And are you trying to find an upper bound for the denominator or a lower bound?
Remember that we are trying to find an upper bound on the whole fraction, numerator / denominator.
So we need to find a lower bound for the denominator?
Yeah, making denominator smaller makes fraction bigger (for positive fractions at least)
So if we want an upper bound on fraction, we need lower bound on denominator
Oh i think i see it now
You take the 4n^2 term out of the abs function, since it's always => 0, and then the rest of the terms can cancel, since theyre always positive, we have an upper bound of 4n/4n^2, aka 1/n
it's not true that |a+b| = a + |b|, even if a is positive
so you cant really take it out
Ah crap
in fact, for n >= 4, you can completely ignore the abs, since 4n^2 - 6n - 14 will be positive
Oh right! And is it that since 4n^2 > 4n^2 - 6n - 14 for positive n, that is what makes those terms cancel?
Wait no that wouldnt make sense i dont think
It's the fact that 4n^2 - 6n - 14 will eventually be positive (its an upwards facing parabola, so in fact itll grow to +infty)
so the | | wont matter in the long term
this is the graph of 4n^2 - 6n - 14 and its absolute value
we can see that for n >= 4, there is no difference anymore
Right right, although even with the abs gone, im not sure how we can upper-bound it further
You want to lower bound it
My bad, thats what i meant
But try making it grow asymptotically slower
When I chose to bound 3n + 9 by 4n, my thought process was that I want to preserve the linear term (something with n), and I want to somehow delete that constant part. So I replaced 9 with n (it will be larger for n>=9) and got 3n + n = 4n
4n^2 - 6n - 14
Here, you'll want to get rid of -6n and -14 and you'll probably want to maintain that n^2 term, since that's what matters the most in the long term (you can change the coefficient though)
Try transforming that -6n - 14 into something with n^2, that'll be lower in the long term
i see what you mean, would this have to be something like -6n^2 - 14n^2, which will be lower than -6n - 14 in the long term?
I guess that would work lmao
oh actually maybe not
anyway, something much simpler would be plain -n^2
i was gonna say, that would result in 4n/-16n^2, which im not sure works as an upper bound
Yeah, the problematic part is that you made the denominator go negative
this should work though
oh right, in the long term n^2 > 6n +14 because polynomials of higher degrees always grow larger than those of lower degrees in the long term
Can you say exactly the point from which it will be lower?
Or any point for which you're sure that it'll always be lower from then on
can you can work it out by plugging n^2 - 6n - 14 into the quadratic formula, and setting n as being greater than whatever the highest solution is?
or alternatively doing -n^2 + 6n + 14?
Sure, that would work
but it might be more convenient to just try some n
10^2 > 6*10 + 14 = 74
oh right
and its pretty clear that it'll continue being bigger from then on
so you can just pick N at least as large as 10
and then when we collect the terms of the denominator, we get 4n/3n^2?
yeah, so now we know that
|a_n - 1/2| < 4n / 3n^2
which is then equal to 4/3n, and that can be used to find a value for N?
oh my god youve saved me 😭 thank you so much 🙏
np
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I have calculated that the no of sylow 3 subgroup has to be either 1 or 7. Now how do I say that it is indeed 7 and not 1?
Should I consider calculating the no of sylow 7 subgroup?
Only one value for that
What's the topic guys
Sylow theorem for group theory
Sylov group
Is there a w in the name!?
Yup but it could be 1 or 7
Yea calculate late n7
Thats for n3
What's the link ?
With it being non cyclic
When both subgroups are normal the group is cyclic
Ryt
So we get k is unique which sylow 7
Now we can't take n3=1
Cause if we do we will get cyclic
Yes
N3=7
And since order of H I.e sylow 3
Each subgroup contain 2 elements of
Order 3
Therefore 7*2= 14 in total
So no of elements is 2*7
✨
Yaay
Thank you 🩷
Btw where are you studying group theory from
Actually i just know what i studied myself from bits of info on internet
By a local writer
Which
S.K mapa
Ok ill check it out
Okay
R u studying for iit jam?
Tho i found better resources
Oh
All is well
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@versed juniper what happened?
@fickle magnet https://judsonbooks.org/aata-files/aata-20250801.pdf
I recently found this book it's pretty good
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I could use help with this problem:
Find the limit of the sequence:
$a_n = tan^{-1} (n^2)$
Lauren
okay, what have you tried so far?
nvm, I thought I typed it wrong and the bot didn't recognize my code as correct... now it posted it 3 times 😄
Ok so, I figured out that the answer is:
$\frac{\pi}{2}$
Lauren
But I wonder how should I do it if it were an exam work or something similar. Do I need to provide a proof or step by step explanation how I do it?
Because I have no idea how to do that specific part correctly
Yes
I thought it had to be continuous at/around some point though, not infinity
Do you know the graph of tan inv x
I didn't know it. I looked it up when I came across this problem. It's actually from a book.
I think I can get the feel on what the correct answer is. At least in this particular case. But I don't know if simply stating the answer would be enough in a test. So that's my question: do I need to prove my answer in this case or do it step by step somehow? And if so, then how?
actually you're right mb 🥶
but the basic idea still applies
You definitely need some explanation at least
(assuming this is a calculus class)
How the explanation would look like?
You could say $\lim_{n \to \infty} n^2 = \infty$
Ari
So $\lim_{n \to \infty} a_n = \lim_{x \to \infty} \arctan(x)$
Ari
and that's pi/2
Thank you very much. Anything else or shall I close?
i will say: usually it's a theorem proven in class that arctan goes to pi/2 as n goes to infinity, but in the rare case it's not, you have to argue that
- arctan is increasing
- the range is at most pi/2,
then since arctan is increasing and bounded above, the limit is the lowest upper bound (pi/2)
but 99% chance your teacher proved this and lets you use it without these steps
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Maybe this isn't exactly a math problem, but a theory question.
" On the other hand, the set of all decimal expansions is not countable.
How come?
Well, if we had a list of all decimal expansions, we could easily construct a number that cannot be on it. Just make its entry j places beyond the decimal point differ by 2 from the entry in that place of the number that is jth on your list . Then the number we create differs from every number on your list and therefore cannot be on it. All of this means that we cannot list all the real numbers or decimal expansions!
Neither you nor I could actually do the infinite number of acts necessary to construct such a number, but we can imagine it done.
To visualize this imagine the first three numbers on your list were
.101010∗
.314720∗
.71324∗
A number not on the list by the construction given would start by .335 since this sequence differs from the first number by 2 in the first place, differs from the second number by 2 in the second place and from the third member by 2 in the third place. The number we ultimately get will definitely differ from the three numbers above. With the rest of its digits similarly determined in reference to the next numbers in sequence on the list, we can deduce that this number cannot be on the list anywhere, so long as the number of its digits is the same as the length of the list.
This means that the set of all decimal expansions cannot possibly be listed. The decimal expansions are uncountable."
I'm not sure if I should ask here but I am genuinely confused. I was reading a section about countable sets.
Can someone help explain why a set of decimals is not countable? I never studied math in english so this is hard to grasp.
Specifically why this author is trying to justify it by saying "the number we create differs from every number on your list and therefore cannot be on it"...
Maybe any concrete examples?
by 'countable' we mean a set of objects where we can make a function that assigns each of those objects to exactly one natural number (so one of them is assigned to 1, then to 2, another to 3, and so on). people often think of this as laying out those objects in an "infinite list" where their position is determined by the natural number associated with them
what this is claiming is, given any function which associates a natural number with a decimal expansion ("lists out" decimal expansions), it must not be able to reach all decimal expansions, since we can always find a decimal expansion that isn't on the list
so there can never be a function which lists out every decimal expansion, which is what we mean by "they are uncountable"
@narrow wigeon Has your question been resolved?
So like indexes of the elements of a list in programming?
How I prove it in my head is that even if you have a list of lets say,
[0.1, 0.2]
indexes 0 and 1
you can still find 0.00000000001 for example in those... but it wasn't included in the list and apparently that makes it so its uncountable
Okay well so far i've only seen examples of decimals between 0 and 1, but what about numbers like floats, such as a list of
[5.1, 7.324234534, 39999.30] would these also be uncountable?
Also the author proceeds to say
"Actually every real number between 0 and 1 has a decimal expansion, but some, namely those rational numbers that end with all 00’s, appear twice as decimal expansions. The reason is that 0.99999... is really the same as 1.00000. Since these are a subset of the rational numbers, this difference is of no particular importance."
which just kills me.
"uncountable" is a description applied to a set of objects
Sry I am just used to viewing the logic through the lens of a programmer
But maybe its completely different
a set (think of this like a data type) is countable if we can make a function which takes in an index (natural number = integer at least 0) and every member of that type is given as an output at least once.
for example the integers are countable by the function
f(0) = 0
f(1) = 1
f(2) = -1
f(3) = 2
f(4) = -2
f(5
and so on. simularly the rational numbers (fractions of two integers) are countable because we can find a function which takes in indices as input and returns every single rational numbers once
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however, there is no function which can take in only indices as input and returns every possible decimal expansion. it can return some of them, but not every single one of them. at least some (in fact, nearly all) decimal expansions will be "left out" and never outputted by that function
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can someone explain to me what sin cos tan are and how to use them
whats the difference between all these help channels?
these are occupied! if you have a question, post it in an available channel such as #help-21|아리스킨충1, or you can help any of these helpees here in the occupied section :)
ope dont post it there now
but you get my point 
what course (general) are you taking, something more geometric or algebraic?
@restive yacht Has your question been resolved?
Geometric
if u wanna learn trigonometry its better to watch youtube
there are a lot of good videos that explain it well
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I dont understand why this is wrong? Its not like the answer is a^2 and b^3.45 etc... Dude I am struggling so much with these questions, I got the two other ones right but only after like 15 minutes... is there a place where I can quickly learn the rules regarding this nonsense.
riemann
hell yeah thanks for those thats huge. I just realized I could do it another way anyways... is this valid?
I dont see why it shouldnt work but it seems a bit too convenient somehow 
it is valid but your radical symbol is too short there
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can you walk me step by step throught he proof of the Guassian correlation inequality
aren't you the same person who just posted a basic question about exponents
im hid friend
...
his*
<@&268886789983436800> some kinda trolling going on here idk
. . .
Please don't troll in the help channels, it makes it harder for the volunteer helpers to give help to people who need it
i swear that was my friend. He saw me on this discord server and wanted to try something. I took back my ipad.
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Need help with this proof . How to go about it
let S be a p-sylow subgroup of H, what can you say about S as a subgroup of G?
@restive river Has your question been resolved?
Ik that the no of sylow p subgroup will be of the form 1+kp and it must divide the order of group
But idk what you are asking for
focus on what the sylow theorems say about conjugacy
i don't think you need counting here
yes
suppose S is a sylow p-subgroup of H
argue why it's also a sylow p-subgroup of G
Cause H IS A SUBGROUP OF G
And for s to be a subgroup of H
It has to divide the order of H
Which further divided order of G
Well to be more clear
dont you have this backwards?
We can use the sylow s first theorem
well the "backwards" part is what we need to prove
but we can't just assert that it's true
you assume S is a sylow p supgroup of G, then show it is a sylow p subgroup of H
I see
sure, and i'm saying we can prove it by starting with the reverse statement and then using the sylow conjugacy theorem
if S is sylow in G then every sylow is conjugate to S, so...
Yup
you'll need to use that |G/H| is coprime to p and you'll also need the normality of H
Ohh
gHg-1=H
yep
How do I use the first one
The co prime
We know p is prime
Therefore [G;H] CAN BE ANYTHING
you want to use that to show that a p-sylow subgroup of H is in fact p-sylow in G as well
anything that is not divisible by p
recall the definition of a p sylow subgroup
If it has order of the form p^n
probably you recall it involves something about the HIGHEST power of p dividing H
??
ok if that doesn't sound familiar then tell me your definition of "S is a p-sylow subgroup of H"
without a definition there ain't no way you're going to prove this
Let G be a group of order p^n.m , where p is prime number and gcd (p,m)= 1 then any subgroup of g of order p^n is called a sylow p subgroup of G
so far so good
now suppose S is a p-sylow subgroup of H
argue why it's also a p-sylow subgroup of G
Hmm let me think
Okay so from the above
defination we get
Let H=p^n.m
o(s) of the form p^n where p is prime and gcd of (p,m) is 1 .
Now H is a subgroup of G therefore o(H)/o(G)
Therefore order of G is of the form p^n . m.k let's say.
Now we already have s being of the order p^n we have to show that gcd (m.k , p) = 1
Okay i am stuck here
Okay i think it's straightforward
S is a subgroup of H and H is a subgroup of G
use [G:S] = [G:H] [H:S]
So it must be a subgroup of G
can p divide [G:S]?
Idk
well if it did, it would have to divide either [G;H] or [H:S], right?
Yes
and does it?
I see
recall you are given
well you want to show that it divides neither
and conclude therefore that it does not divide [G:S]
so why does p not divide [H:S]
Idk tell me why
we assumed that S is a p-sylow subgroup of H, right?
Yes
so if H = p^n m (where p does not divide m) then |S| = p^n
and therefore [H:S] = m
so...
ok so far so good
p does not divide [G:H] and it does not divide [H:S]
therefore it does not divide [G:S] = [G:H] [H:S]
therefore S is a p-sylow subgroup of G
agree?
Yup
ok good
Understood so far
now use the conjugacy theorem for sylow subgroups
all p-sylow subgroups of G are conjugate to S
therefore...?
S=gHg^-1
no..
S isn't conjugate to H unless S is all of H
in general S is properly contained in H
I don't understand this statement
how can S be conjugate to a group that is larger than S?
conjugation is an isomorphism
Ohh yes wait
We can do contradiction
Here
Okay nvm i couldn't make it make sense
I got S=H
Since H is normal
What if S is improper
Subgroup
it will be, in general
It can't
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I did this problem wrong
So I’m doing it again
My diagram I just drew is there in pen writing
Here are the identities we learned related to this problem
so how is the second attempt going? did you use the identities here? whatd you get
This is my second attempt
I labeled the triangles based on what I was given and then I just did secant of theta
So 3.42/-1
well, you also need one identity to use there
Oh 😭
well, luckily for you tho, since cos(x) = cos(-x), you also get sec(x) = sec(-x)
but you gotta mention that explicitly
tho personally, if you need to solve it using the identities, dont use a diagram to do this
Oh
well, if sec and csc were flipped in the problem, youd have to use csc(x) = -csc(-x), meaning csc(-x) would be +3.42 instead
well, if the problem said If sec(pi/2 - theta) = -3.42, then find csc(-theta) then youd state csc(theta) = sec(pi/2 - theta) = -3.42 from identity 18(or 19)
and then use the other identity csc(-theta) = -csc(theta) to say csc(-theta) = -(-3.42) = 3.42
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I received this question on a midterm review. I was trynig to solve it, but it doesnt make sense. by the alternating series test, the terms of f must go to 0, however, a simple contradiction f = x+2 just keeps oscillating. Is this question incorrect?
Wouldn't it be 1/n + 2 then which would basically be an alternating harmonic series with a known sum
hmm. but it still doesnt go to 0 right, which is one of the requirements of the alternating series test?
and wouldn't it constantly just have -2 + 2 -2 + 2 which diverges
math is hard
yes this is false as stated
also since yall are here, there are 2 more things i need yall to confirm. there's no way this could be 5x-1 in the exponent right?
thanks
its 5n-1 right? cause i dont see any feasible way to find an anti derivative of x^5x-1
yeah it has to be 5n-1
this problem set has way too many typos
yeah sorry to hear that man

wild ahh
and in this one, the x is supposed to be inside the brackets of the sin right?
cause if not i dont see a point in asking about the existence of second order derivatives when its essentially a linear function
has to be...
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Can someone explain why desmos is telling me that cosx<1 for all x and why since<1 for all x. They both equal one at times so this cannot be true
post the exact thing?
Wdym? You want ≤?
no, =
Why is that? Interval is too big
Equality doesn't give us anything
should give you any value of the form kpi for sin or kpi+pi/2 for cos
Where? In desmos?
@robust bobcat Has your question been resolved?
it's just too small for desmos to draw
In general you cannot trust graphing calculators on things like this
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How do I solve this I tried to integrate but can't seem to prove it
You're done with the verification part, right?
No
Oh, just take the derivative of y = sin(1/x) for that part.
Have you learnt how to differentiate sin(x)?
$\frac{-cos(\frac{1}{x})}{x^2}$
codo0160
What do I do next?
$\dfrac{-cos(\frac{1}{x})}{x^2} = \dfrac{x\cos{\left(\frac{1}{x}\right)} + 2\sin{\left(\frac{1}{x}\right)}}{x^2\cos{\left(\frac{1}{x}\right)} - 2x^2\sin{\left(\frac{1}{x}\right)}}$
Erebus
Try showing this is true
If it doesn't match up, there might be something wrong with the question.
Yes.
But what do I do to the condition?
Well, a way would be to try finding y first and using the condition to find the required function.
But I think the question might be wrong.
Because the first part failed.
Yes
Have you try checking the original source?
I think maybe it was a trick question
Because that's the same assignment I got
So I'll conclude that it's not a solution
Well, it'll be even trickier if you found a solution for y. 😆
Let's try to integrate dy/dx.
I think it should be y = -x + c
From how I think of it, since it's asking for other possible answers for y, I think we would just need to find x and find y (not 1).
$y = 1$ is a \text{solution} $\implies (x - 1) \cdot 0 + x - 1 = 0 \implies x = 1$\
\
Solve $(1 - y)\dfrac{dy}{dx} + (1 - y) = 0$
Erebus
There might be other possible solution apart form y = 1
But what happens to c?
Can't it be $y=-x+1$
Since the coefficient of x in y = 1 is zero so we can assume c = 1?
codo0160
We're not talking about c yet.
c can be any constant
It's just that we're looking for alternative solutions for y
apart from the given solution which is y = 1
@vast basin Has your question been resolved?
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shouldnt there be a f^(2n+2) term in the addition of F''(x)+F(x)?
What are F and f here
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i need to prove this:
Theta(...) means both are a big O of the other
change of log base rule
$\log_b a = \frac{\log_c a}{?}$
Rafilouyear2026
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how would you solve questions like this?
ok so
and then you can set up equations according to what they said
n is my ten tens
m is my unit
10(tens) + (units)
mhm
if it says the two digits are reversed is it
10(units) + (tens)?
ok what do i do with these two equations now?
10m+n = 3n + 18??
solve them as a system of equations.
{ units digit + tens digit = 9
{ 10m+n = 3n + 18
is that correct
that's one of the equations you can write down with the given information
you would want to write the first equation in m and n as well.
mhm but for the first equation you may simply write n + m = 9
then just use your favourite method to solve the system.
something is not right
m = 9 - n
10 ( 9 - n ) = 3n + 18
90 - 10n = 3n + 18
72 = 13n ???
I see you rearranged for m in the first equation and substituted it into the second equation.
but during the substitution, the + n originally on the left side in the second equation is suddenly missing.
your original second equation was 10m + n = 3n + 18, but after substituting it became 10(9 - n) = 3n + 18.
fixing that should give you the right solution.
n + m = 9
10m + n = 3n + 18
m = 9 - n
10 ( 9 - n ) + n = 3n + 18
90 - 9n = 3n + 18
72 = 12n
n = 6???
and then
well, yes. not sure why you need to put three ?s after the final answer. hope you don't do that on tests.
i dont only on my copybooks
so commanding
m = 3
correct.
to cross-check, you should check that m and n form the two-digit number that was asked for in the question, including by swapping the two digits and checking the condition.
so
n = 6
m = 3
10 (6) + (3) = 63
so 63 is your number. its digits does add to 9 as required.
now, swap the two digits and make sure that the second condition is also respected.
18 more than 3 times the tens digit of the original number (6).
yes.
yes
that sounds like the right idea.
you may want to write this on paper or a drawing program.
yeah
b = 3a - 20
the b is positive on the right side, if I'm seeing things correctly. so all you want now is to move the 20 to the other side by subtracting both sides by 20.
you may wish to show your working for checking.
yes it is correct
its sending
sorry if its a bit messy cuz i had a big brain moment during solving (i ususally get exciting solving complex questions cuz its fun and interesting lowk but each to his own)
I'm sorry to say that I can only read the first line (45 = 20 + b), but from what I can make out from the second line (correct me if I am wrong, I apologize for my vision), I see
+b = 20 + 45 (?)
which does not follow from the first line.
oh yes
+b = -20 + 45 (i added strokes when i was reversing the signs, my fault)
after that
b = 45 - 20 ( i rewrote it so it looks more manageable for my eye)
b = 25
then
a/b = 15/25 = 3/5
which is true
if that is the case, then you are entirely correct. please forgive my poor vision.
its okay
its my fault for not being clear enough lol
i was rushing because i unlocked a whole new dimension of reality while solving this
I am glad that happened (?). it always feels nice to solve a problem you had been on for a while.
but also it's not your fault.
is there anything else that you would like to ask though?
looks familiar
please allow me some time to read the image.
looks like y = mx + b
it is reminiscent of the slope-intercept form of a linear equation, yes.
but in this case this does not matter. you can again create two equations with the two pairs of values, and solve the resulting system as you did for the past two questions.
4 - n = (1)m
now the other one.
looks to be correct. now just solve the system as before.
can you show your steps, perhaps? maybe something went wrong rather horribly.
I did get m = 2 from a preliminary attempt earlier.
maybe the way i did it was too complex
this does not help, as we still have two variables in a single equation.
oh yeah
oh i did it wrong
its corect
m = 2
had a little oopsie daisies
anyways
4 - n = 2
n is also 2
if you let the speed of the wind be w and the speed of the plane be p, can you form a system of equations with w and p?
keep in mind the relationship between speed, distance and time when doing so.
w is TBD
p is 217
uhh
i actually dont know the equation for
speed distance over time right
p is not going to be 217. form the equations with w and p as they are.
speed is indeed distance per time, yes.
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✅ Original question: #help-27 message
double-checking that what I am seeing is
P + W = 217
P - W = 155
I haven't checked the numbers, so if the numbers are correct, then this is the right method.
well done! is there anything else you would like to ask?
alright, then I believe you may close the channel. all the best for your next questions!
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how do i solve for x?
ik i need to like, cube the entire thing and solve that but i'm doing something wrong when i cube it
cause my calculator's giving me imaginary numbers and the answer should be approximately 0.003684
what are you putting in the calculator
how would you even put this into a calculator
it has a polynomial solve function
oh wow
a CAS type
so i put in x^3 + 0x^2 -(number)x + 0
cus if i cube it'll be -ve still
but... it seems to give me imaginary numbers
so something's not right
i don't think you cubed it right...
probably, that's basically my question
are we required to use a calculator here
you should have x^4/3 terms and such
how do i cube it cus clearly i'm doing it wrong lol
well do you know that (a + b)^2 isnt a^2 + b^2
not really, i'm looking for like
do i cube the number before the x or whatever
yeah ofc
oh ok
here is something to relieve headache
i've not done this in ages so i'm really rusty
replace the big scary decimal number with something like A
for compactness
$x - Ax^{1/3} = 0$
Ann
tried and true method
add $Ax^{1/3}$ to both sides and get $x = Ax^{1/3}$
Ann
do you see how this can simplify further
since you have Cas, just define A = that decimal
honestly no, my brain is fried rn
i've been doing this for a few hours
but it should be so simple 😭
like i'm just trying to find when 2 depths = the same depth
so when i minus 1 from the other and get 0
anyway this is a good jumping off point at least
ig i should take a break
i may return in... an hour potentially. thanks for the help lol
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Can someone e help me out with without this problem
Yes
Basicly you need to see if the operations made to pass from one expression to another are “legal”
Or maybe another way, is to give some values to x , and see that both expressions give the same result
But the first method is better, as its important to know what operations you can and cant do

