#help-33
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gauss-jordan requires about 50% more operations for large matrices
and is also numerically unstable
What does that mean? Edit: I can search things up
so it's good for hand calculations (which use small matrices and precise fractions) but not suitable for computer algorithms
Floats be like: $0.1+0.2\ne0.3$
BBMaths
Start from the bottom row and work backwards (it’s in the name “back substitution”)
Like z=-1 then put that in the next row up and get y
z doesnt equal that
you do the back substitution process on the yellow one (since it's in REF)
.
-32z=32
you could do it on the second to last one as well but then you get -32z = 32 which can still be solved for z
So z=-1
to find y, you go to the next equation above, which is y + 3z = -1, and plug in the value of z you got previously
The green one is 2y+6z=-2 which will give the same answer it doesn’t matter which you choose, you could even switch back and forth between the different matrices here!
oh ok
Only because they relate by row operations
Since row operations are about keeping the same x, y and z solutions but changing the system of linear equations
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Hi guys does this look correct? This is for conic sections and I use the matrice function on my calculator for it
Did you already verify by hand? As in plug your x and y values in and find that the equation holds?
let’s just say…. No
Do that. It's the best way to do so because you can do this without using some fancy technique. Just put it in your calc and see.
yes it was
If I'm not mistaken the first column is the given x, the second column is the given y, and what is the third column for?
I’m not all too sure, when my teacher taught it she Included the column but it always was the same number in the examples
That's a problem if this test question is calc required.
Gulp
Alson in your written solution A and C seems to have disappeared.
81-36
How did you get the fourth column?
Beyond the verifying by hand I am of no help here since I never used a calculator for this purpose. Sorry. You should call for other helpers.
Ah, I understand. Thank you for the help regardless
Oh my god 😭
Should’ve learned my algebra rules probably
Went straight to calculus instead
AH THAT WAS UT
THANK YOU WAHAHAHAHA
Make sure though.
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i need help on b. i used a hessian calcualtor online and i can easily see that not all of the entires of the hessian will be positive
@quaint arrow Has your question been resolved?
<@&286206848099549185>
@quaint arrow Has your question been resolved?
<@&286206848099549185>
thank you for the response. this makes sense to me, but the directions say to use the second-order definition of convexity
thank you so much for the response. I understand most of it. But i think i am slightly confused on differentiating matrices. Specifically, how did you go from 2·a(s)·w -> 2·a(s)·I + 4·a'(s)·w wᵀ?
im sorry, i'm having a bit of trouble doing product rule. did i set u v improperly?
@chilly valley thank you so much for your help
you really helped! Have a good day mate
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dear god I really hope chatgpt was correct.
@quaint arrow this guy was caught using an LLM on nearly all the questions he answered. I hope you’re able to able to double check every thing you got from him… 
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If a sequence is bounded and it is converges to A then every subsequence of this sequence will Converse to A
I guess it is true
where is question
i mean why do we need it being bounded
Actually i am reading some notes
So doubt arises in mind🙈
We need to be bound otherwise we can't say anything
no?
(-1)^n
no need to mention it
you are reading notes and you are only certain enough to say "i guess it is true" about something that you yourself wrote in your own notes written by your own hand?
n^2
I didn't write these notes. I am reading coaching notes
no need to mention it being bounded
this is not what you said before
They also mentioned bounded?
saying it’s a bounded sequence is a preliminary assumption
also what is cps
are you trying to prove 7 btw?
Yeah
I am asking about it only
Wdym?
proving either direction
I don't need to prove just need to understand
subsequences is part of sequence
so sequence is converges to L then all points are travelling to that limit slowly
why slowly?
Subsequences will also travel in that direction
what do you mean by slowly
🤔
I mean points which is very close to that limit can be Faster
Nevermind my words
think back to the definition of convergence. it requires that regardless of the distance from the limiting value, beyond a certain point eventually all of the sequence members will be within that distance from the limiting value. now since any subsequence you choose "extends" into this tail part of the sequence where all of the sequence members are hanging around the limiting value, we can just as easily say this subsequence also converges to the limiting value because it’s also in those neighborhoods
does this make sense?
yeah makes sense but please write more in simple English
i didn’t use big words
If I have a bounded sequence
I can't say it is convergent
(-1)^n
we have two limit points
ok sure what’s your point?
notice that we can find two subsequences that don’t converge to the same value
So for convergent we need unique limit?
take one subsequence to consist of the even terms and one to be of the odd terms
If the sequence is convergent then what can we say about convergence of subsequences
This is my doubt
I mean each and every subsequence is converging so they will Converse to the same limit am I right
they don’t lie in the same neighborhoods but together they form the entire sequence and since they don’t hang out in the same neighborhoods the entire sequence certainly doesn’t converge because it needs all of its homies in one place
they all converge to the same value that the entire sequence converges to
I am asking in rerverse
My doubt is about subsequences
1/n...it converse to 0
if I take finite subsequnces
1,1/2,1/3
is this converging to 0?
I'm sorry my doubt is messy and not clear
Maybe i am mixing lots of unfruitful things
subsequences are not finite lists
I see. They need to be infinite?
they are sequences within the sequence
Great!!
yes. it doesn’t make any sense to talk about convergence for finite lists of numbers
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is the ans to both just that f(x) and g(x) that they are continuous for which those statements hold
that seems too short of an ans
@hearty dust Has your question been resolved?
Yeah
am i missing smth to my ans?
Nothing I can think of
That’s the main thing
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guys, i dont understand f and h
for f, isnt Central Limit Theorem only applied when n is large and when distribution is unknown?
and for h, why is it false?
@near elbow Has your question been resolved?
i dont think f and h are even related to central limit theorem
those equations are related to the distribution of a sample population
another helper can mistake me if im wrong
oooo
alrightt thankyouuu
ye no worries
@near elbow Has your question been resolved?
bro wut 😭
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what?
whats the domain of cos-1 y
[-1 ,1]
so then what is the interval in which |x-1| lies
think about it
2 less than or equal to x and x less than or equal to 0?
yeah pretty much
Shud i switch signs if i apply mod?
But its the opposite
yep
whats the answer
[0,2]
its just what you said
i mean thats just the proper way of writing it
cus if you say 2<=x<=0 that means 2<=0
which isnt true
so you write 0<=x<=2
try it for yourself once
yes
oh sorry
if you meant the 2 in 2x
then it will affect the domain
the 2 of 2cos-1 2x doesnt
correct
because its x^2
if x is negative then (-x)^2 = x^2
so its symmetric
(-1)^2 = (1)^2 = 1
(-1/2)^2 = (1/2)^2 = 0.25
alright
even so
-x^2 = - (-x)^2
so - (1/2)^2 = - (-1/2)^2 = -0.25
-(1)^2 = - (-1)^2 = -1
basically we have that -1 < -x^2 < 1
Wait wait
I dont understand this
oh the minus sign became a bullet
Oh
Ye
so -1 < -x^2 < -1 then -1 < x^2 < 1 then -1 < x < 1
i skipped a step, should i elaborate that?
But for +x², doesnt -1 become 0 since x² always greater than or equal to 0
yeah so we have 0<x^2<1 we dont even need to care about the -1 part
since 0<x^2<1
x must be between -1 and 1
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guys i dont get the question of 1b
this is 1a
what's the probability that the confidence interval doesn't contain the actual population mean, and in fact the population mean is bigger?
so P(mean > 13.0)
@near elbow Has your question been resolved?
ohhhh
thats 0.005
i was thinking of 0.01 but since it should be bigger than 13.0 then it is 1/2 of 0.01
but how do you know that the population is bigger?
@near elbow Has your question been resolved?
"...confidence interval will be below the population mean."
ohhh
okkk i get it
thankuu sm
thankyouuu sm
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step 0 is to take off that literal fucking HITLER PFP. <@&268886789983436800>
my man what is that pfp 💀
ig he just got rejected from art school
But why the question is also closed?
op closed it irrespective of the hitler-wannabe that showed up.
Hell, even a blank pfp is better than that pfp

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if i(n,a) =(1-2x)^(a-1)(x-x^2)^(n+1)/(n+1)+2(a-1)i(n+1,a-2)/(n+1) where i(n,a)=\int (x-x²)^n (1-2x)^a dx find i(14,28)
.
can you send a picture or write what this i(n,a) thing is in proper LaTeX please
if $$I(n,a) =\frac{(1-2x)^{a-1} (x-x^{2})^{n+1}}{n+1}+\frac{2(a-1) I(n+1,a-2)}{n+1}$$ where $$I(n,a) = \int_{0}^{1} (x-x^{2})^{n} (1-2x)^{a} dx$$ find $I(14,28)$
.
HERE
aight wait
you give two different defns for I(n,a)
one of which is a function of x and another which isnt
inconsistent much?
show your derivation
i first did it for my actual expression, for 1-2x whole to the power 28, hence got 54 in that 2nd term involving i(n)
but otherwise, generally, the 1st expression is the recurrence relation needed here
@rich isle Has your question been resolved?
@rich isle Has your question been resolved?
@rich isle Has your question been resolved?
Can you send the question again?
.
check pinned meessages
have you tried substitution
like
taking x-x^2 as some variable z
the expression becomes [(z)(1-4z)]^14
smthing like that mybe
no
<@&286206848099549185>
ask sm1 to pin the LaTeX one
the present one is messy
Notice that d(x-x²) = (1-2x)dx and that here 2n = a
<@&286206848099549185>
You may find errors but it really is the idea
there is a small sign error in the IBP but the computation remains coherent

<@&286206848099549185>
I would write $(x-x^{2})^{n}$ as $x^{n}(1-x)^{n}$ and then do ibp
డ్ర్యాగ్లొక్స్
can anyone solve these
!occupied
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A way to solve I(14,28) is to expand the terms raised to the power 14 / 28
It demands a lot of computation (using Newton Binomial formula) but it gives the solution
help please
maybe draw it out on a paper so u can visualise better
and id say also write out the formulas for area and pythagorean theorem on an equation
<@&268886789983436800>
PELASE HELP!!EEEE
@rich isle Has your question been resolved?
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i give up on this can someone pls explain the entire thing like how did your brain work through finding patterns to figure this out
like i was thinking after the 3rd term, we can see that it becomes 2^1, then 2^2, then 2^3
and we also notice that the difference between the terms after the 2nd and 3rd also go up by 2^1, 2^2
for example, 5-3=2, 9-5=4, 17-9=8 and so on
so what i came down to was (2^(n-4)) / (2^(n-2)) but obviously this doesnt work for the 2nd term
then i looked at them seperately and still couldnt figure it out
so i give up and require help
Yeah you already guessed a formula right, try getting it right for everything from the 2nd term onwards
what is OEIS?
Though you could argue the formula is
n=1...6: these 6 terms
n=7...: always 19
the answer is not unique, so, any answer will do
this isnt a math problem
im ngl to you idk what this means 😭
it means the following is a valid answer:
It's just saying the first 6 terms are as given and any further terms are 19
1/4, 1/3, 2/5, 4/9, 8/17, 16/33, 19, 19, 19, 19, 19, 19, 19, ..., 19, ...
one pattern i noticed for every term other than the first and second:
the sum of the denominator of the previous term and the numerator of the current term is the denominator of the current term
ohhh
which is a valid continuation of a sequence, just probably not what the person who set the question had in mind
unless that person is me
But try this, carefully
the first term might be a bit problematic for now
like these differences - can you modify the numerator and denominator of your fraction to match the sequence, from the second term onwards?
idk
i mean i couldnt figure out a way to modify it so that it would fit
the entire series
it always breaks on the second term
consider multiplying each of the fractions for n >= 2 by 2/2
pattern should be clear
$\frac{1}{4}, \frac{2}{6}, \frac{4}{10}, \frac{8}{18}, \frac{16}{34}, \frac{32}{66}, \dots$
knief
1/4, 2/6, 4/10, 8/18, 16/34, 32/66, ...
Numerator: 2^(n-1)
Denominator:
6 - 4 = 2 = 2¹
10 - 6 = 4 = 2²
18 - 10 = 8 = 2³
34 - 18 = 16 = 2⁴
66 - 34 = 32 = 2⁵
...
T(n) = 4 + (2¹ + 2² + ... + 2^(n-1))
T(n) = 4 + 2(2^(n-1) - 1)/(2 - 1)
T(n) = 4 + 2^n - 2
T(n) = 2^n + 2
Thus f(n) = 2^(n-1) / (2^n + 2)
ty
so it just comes down to figuring out if its possible to unsimplify the numbers
then going for patterns from there?
ima try this tw
ty*
yea the idea was that we have a nice sequence of powers of 2 from the second term onwards but the first term breaks that so we multiply by 2 to all of the fractions from the second term onwards
np
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im so stuck after this part
yes
no
$\int (f + g) = \int f + \int g$
Médicis
yea but you have an additional 1/2 on the 1/2 which presumably comes from the factor outside the integral
if you want to distribute it inside the integral then it also needs to be multiplied by the 1/2 cos(2x)
lets do it step by step my brain is not getting it
$\frac{1}{2} \int \frac{1}{2} + \frac{1}{2} \cos 2\theta \dd{\theta} = \int \frac{1}{4} + \frac{1}{4} \cos 2\theta \dd{\theta}$
knief
what is written here is wrong
so u got that first 1/2 because it was already from 1/2 cos^2 theta d theta
then after the integral
the 1/2 is the 1+ cos2theta / 2
what is unclear?
what about them
i understand the 1/2 before the integral
that comes from splitting the fraction
$\frac{1 + \cos 2\theta}{2} = \frac{1}{2} + \frac{\cos 2\theta}{2}$
knief
yes
sure
but theres an extra theta idk where that came from
$\frac{1}{4} \int 1 + \cos 2\theta \dd{\theta}$
knief
wait whered u get the 1
$\frac{1}{2} \int \frac{1}{2} + \frac{1}{2} \cos 2 \theta \dd{\theta} = \frac{1}{2} \int \frac{1}{2}(1 + \cos 2\theta}) \dd{\theta}$
knief
Compile Error! Click the
reaction for more information.
(You may edit your message to recompile.)
its 1/2 times everything inside the integrand
is this right so far
i mean yea
okay i see now u bascially factored out the 1/2?
so now
u kick out that 1/2
and then whats left inside is the
1 + cos2theta
now we integrate
step by step
1 is just theta
and multiply by 1/4 so thats how u got 1/4 theta
so now we have cos2theta
which is sin^2 / 2 times 1/4
what
oh crap right
so i kick out the 2 there from cos2theta
that makes my 1/4 into a 1/8
i have it written down as
1/4 times cos2theta
i get it wrong sometimes and do 2/8 instead of 1/8
how do i avoid that
take the factor of 1/4 then divide by 2 for reverse chain rule on cos(2theta)
cos turns into sin
because sin differentiates to cos
by kick out do you mean divide by 2 because of the 2theta
would this be written as
1/ 4 times sin 2theta / 2 + c
what
why not make it 1/8
im just going stepbystep to make sure im doing it right
i mean if it helps you then sure
what about it
sin(2x) = 2sinxcosx
whats this called again
double angle identity
ok great
this part is the part where u go back to x is what i understand
i think i got it from here
thank you
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help?
caan you show how you got your answer?
i didn't
was it gpt?
Notice that u have a geometric series
yes
Do u know how to compute a convergent geometric series?
i don't have my notes with me i forgot at friends house so it's hard to do the hw rn, like for me to do, ykwim
search up sum of infinite geometric series
you'll find some videos
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i did some rough work
just to visualize
the question a little bit
but dont know how to even begin proving here
Tips: there should be a neat bijection by marking "1" as the "start of the number"
@lusty island Has your question been resolved?
hm
is this for if the compisition starts with 1 or 2?
You first prepend the composition with "1"
ok...
Note that:
1 = 1
3 = 1 + 2
5 = 1 + 2 + 2
7 = 1 + 2 + 2 + 2
...
right
i think i need a little more elaboration
For example, for n = 5, the possible compositions are:
5, 3 + 1 + 1, 1 + 3 + 1, 1 + 1 + 3, 1 + 1 + 1 + 1 + 1 = 5
Rewrite it in the above rule results in:
1 + 2 + 2, 1 + 2 + 1 + 1, 1 + 1 + 2 + 1, 1 + 1 + 1 + 2, 1 + 1 + 1 + 1 + 1 = 5
Now, if you drop the leading one, you get:
2 + 2, 2 + 1 + 1, 1 + 2 + 1, 1 + 1 + 2, 1 + 1 + 1 + 1 = 4
Sounds familiar?
oh if you drop the leading one it gives you the composition for the previous one?
Yes
@ruby mulch
ignore the visuals
thats for me
to understand lol
thanks for the help
i dont know how you guys come up with proofs so well
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i ran through this problem and dont know what to do
Find the absolute extrema of the function on the closed interval.
What have you tried?
i tried solve for the derivate of that problem
set it = to 0
and put x = -3 , x = 6 for the derivate
Did u try using the x value from when u set the derivative to 0?
yea
this is my work
It's x=0 and x=1
your maximum looks right
Happens
well- the x value is right
make sure u remember to plug your x value into the original function, not the derivative
oh
nope...
i try to put it to canvas
idk what graph to look for
Okay
Do u know what the derivative means in context of the original function?
hmm just one degree less?
Not quite
i actually dont know what is the derivate, i just apply the formula lol
Okay
or sometime they ask to find a slope
You're getting warmer
i do the derivate, put given x into the derivate to find slope
and do y-y1 = m(x-x1)
Okay
so, if, for example
i have a function f
and i evaluate the derivative of that function at, say, x=3
i get..?
okk....
say the blue graph is my function
and the red line is a tangent to the function at x=3
then the derivative of f at 3, f'(3), will give me the gradient of that tangent
So what do you think happens when I take the derivative of a function, and set it equal to 0?
It will give me an x value, yes
but what does that tell me about the original function at those points?
oh ...... a tangent line pass through the point
Not quite
The derivative always tells me the gradient of the tangent for a graph
so if my derivative is 0, then the gradient of my tangent is..?
it would be 0, yes
which would mean it's a straight line
so if we look at this function, the derivative should be equal to 0 where?
try imagine the tangent at different points
exactly
its a constant line
exactly
so, for any function f, setting the derivative to 0 and solving for x will give me the x-values for..?
yes, (and stationary points of inflection, but we dont need to worry about that here)
So if we go back to your original function
$f(x) = x^3 - \frac{3}{2} x^2$
Hyper
absolute minimum and relative minimum are correct
are you sure that's the absolute maximum though?
yea i would say unsure as well
because the graph goes infinity
i think that is relatve max
yes
i was gonna ask you about that question but idk how to say
let's pretend that's the whole graph
so abs max = DNE
if the graph was defined for all x, yes
so if we go back to your original function- how would you approach finding the absolute minimum and maximum?
(remember the closed interval)
i just plugged in x to the original function
because that is where the line touch the lowest close interval
and would do the same thing to find max
hmm for this problem is it true that i wasted time doing the derivate, i just plugged in x = - 3, x=6 i have my min and max already
it's useful to know how to find minimums and maximums with the derivative
Go for it
the problem with this is that , i got the minimum wrong
i try to set the problem = 0
hmm i think i forgot the set the orinigal equation x = 0
Nah, you wouldnt set the original equation to 0
There's an error in your working when u set the derivative to 0
2/(3sqrt(x)) cubed isn't x/8 * 8/x
instead of cubing, try squaring
like ()^2 ?
yes
....
ok here
oh oh then i just multiple both side with denominator
i found x =0
now plug it in to find the minimum value
waitt my bad i misread your original working
Nevermind- u were right the first time
that's my mistake
The derivative is 0 when x=1, yes
oh ok
But it's not quite the minimum still
but that isnt the answer for the minimum
is it factor??
nah not quite
think about it graphically
what does the graph of $3x^{2/3} -2x$ look like
doesnt need to be technical, just a rough drawing is fine
Hyper
hmm
no idea
but i can use desmo
i mean
using desmo
it gave the sauce already
my bad on this one i do not what the graph looks like without desmo
it would take me years
lol
actually not years, i just plug in x = 0,1,2,3
if u ever want to graph it without desmos
think of the graph as two different functions
3x^(2/3)
and -2x
and you're just adding them together
you can graph both of those by themselves, then draw your function
yea
So what have you got for your minimum?
i put 0 in for x
lowkey it tells me that 3(0)^2/3 - 2 ( 0 ) would just be 0
anything time 0 = 0
i got (0,0) for minimum
That sounds right
yea thanks to desmo for that
but it lowkey works for me
thanks for the help !! really appriciate it
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in linear algebra, if i know the standard matrix representation of two linear transformations $K, S$, is the standard matrix representation of $K + S = [K] + [S]$?
dis_da_mør
I ended up getting the correct answer but I am not convinced with the method I used to solve I am sure there are plenty of mistakes
Someone pls tell me how can I better approach questions like these
sorry this channel is occupied
Thanks
re-sending the original question:
in linear algebra, if i know the standard matrix representation of two linear transformations $K, S$, is the standard matrix representation of $K + S = [K] + [S]$?
dis_da_mør
from what i can see if both transformations have the same origin and destination vector spaces (so their matrices are the same size) then yes
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"the ratio between the reading of the ameter before and after closing K"
how is it any of these options...?
before closing k, the whole current would go thru the ameter
so it would be I""
after closing K, the current is gonna be split in half
so... 1/2 I
I / (1/2 I) is 2
which is not in the options
but the current is also higher after closing the switch because the whole circuit has less resistance
oh... 2/3
1 / (2/3)...?
I calculated the overall R, did Vb/R, split that into two
I : 2/3 I
yeah its right
ty cloud
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Hello! I am working on a proof of this exercise from Herstein's "Topics in Algebra":
Sketch of my proof goes as follows. The first sentence in the problem is basically a fancy way of saying that left coset equals right coset for all elements of G, i.e. Ha = aH.
And if so, we can easily prove that gHg^{-1} = H for all g from G. (because gH = Hg means that for every h from H, there is a h' from H such that gh = h'g, then we can multiply by g^{-1} on the right and get ghg^{-1} = h' which would eventually establish that gHg^{-1} = H for all g. So as a side effect we will establish what is asked in the exercise (i.e. that gHg^{-1} is a subset of H).
Yes
my question is: why does Herstein ask for something milder?
i.e. why doesn't he ask to prove a stronger result (equality of sets rather than just A is subset of B)?
am I missing something in the statement?
because there is a bijection between the two?
so they have equal number of elements, hence there can't be anything missing on the left?
In the finite case that will work
well, in the finite case, yes
But generally the double cosets form a partition of your group
And so if any two (double) cosets have a non-empty intersection then they are equal
Really it just aHb instead of aH or Ha
ok
OK, I see, so basically we are saying that H is a double coset (with a=e, b=e) and gHg^{-1} is a double coset (with a=g, b=g^{-1}), and they have non-empty intersection (because one is included in the other and is not empty), and since they form a partition (just like normal cosets) - they are equal
Yes
OK, so the summary is that Herstein is asking us to prove something equivalent (that looked weaker to me, because I didn't know that it was equivalent -- or at least I have to prove that). I suspect though that he may have had some other proof in mind, that would more naturally lead to that subset formulation...
but there is no way to tell because there are no official solutions from Herstein himself 🙂
Maybe yeah
Ptobably something like, take x=ghg^-1
And take a look at the coset Hx
Showing it must be equal to H somehow
but then elements of that coset would be hghg^-1?
i.e. with two "h"s
I found this exercise quite confusing overall, especially before I reformulated the first assumption to simple aH=Ha. Actually I came to this from the end, i.e. I've just seen this property of cosets (that aHa^-1 = H if aH=Ha) in another book and then I realised that I just need to show that aH=Ha and then I am done. And then I realised that the assumption of the problem is just equivalent to that -- it took some time to persuade myself 🙂
Maybe its a good idea to gather your reasoning on why is this statement is equivalent
on equivalence of "aH=Ha" and "whenever Ha != Hb then aH != bH"?
Yes
@clear arrow Has your question been resolved?
my reasoning went like this. Let's reverse Herstein's statement (i.e. make a contrapositive statement). Then it becomes "if aH=bH then Ha=Hb" (for all a,b from G). In words, alternatively, "if two elements are in the same left coset, then they are in the same right coset". We know (from previous exercises or the book) that left cosets (and right cosets too) form a partition of G. A partition of a set is fully defined by specifying for each pair of elements whether they are in the same part or not (because this relation "a and b are in the same part" is basically the same relation for corresponding equivalence relation). And our statement said that "if two elements are in the same left part, then they are in the same right part", so this relation is defined identically on one partition and and on another, leading to the same parititions for all a and hence aH=Ha in general. But this one is somewhat messy (and also it looks like our statement about pairs goes only in one direction A -> B, not necessarily A=B, so I need to do some workaround for that too)
there is probably a simpler way of demonstrating this...
Using this observation and using a two sided inclusion to prove aH=Ha can work
If you want to go through the details
if x in aH then xH=aH and and so Ha=Hx, and so x = e * a in Ha
The one sidedness of the given statement is not a problem as if aH=bH then
Ha^-1=Hb^-1 by taking the inverse
yeah, makes sense
haha, yes, it's good, but I only played a little, should come back to it at some point, it was fun
I have 1300h on it 😵💫
And I am always just messing around
Late game of the new dlc is tough
wow 🙂 that's definitely not "a little"! 🙂
for me it was like this: I liked the game and started to "sell" it to my friend, who got hooked, and then somehow I myself almost stopped playing it 😅
The ability so sit down an truly enjoy gaming has been going up and and down in phases
Right now I found two new games to add to my top 10 ever.
what are they?
Finished one already, and having fun with the other
Clair obscur: expedition 33 and blue prince
ah yes, got those two on Game Pass, but haven't played yet, only watched some let's plays on YouTube 🙂
I recently played Baldur's Gate 3 and Kenshi 🙂
Barely know anything about these tbh
When the time comes I might play one of them
I have enough things related and not related to gaming to do
Yeahh and group theory is just the begginning of abstract algebra
you have rings, fields and then dozens of ways to continue
I am currently battling Algebraic Geometry
I also wanted to discuss my study plan, but that's probably something that's better to do in the relevant channel for abstract algebra
and another time, because I need to get back to work 🙂
Cya
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lim f(phi) = f( lim phi )
!original please
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.
Help me with the last property
Ah limits commute with continuous functions
@stone hound Has your question been resolved?
<@&286206848099549185>
@stone hound Has your question been resolved?
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Official explanation
my answer: 16 sqrt 2
my reasoning: side is 32, center of the circle would be center of the square, so find half diagonal length
$\frac{\sqrt{32^2 + 32^2}}{2}=16\sqrt{2}$
UCYT5040
so it means like, to the nearest point on the circle?
Ahhh yeah, they're not asking to centre of circle, only the circle
Yup
ok that makes sense
just kinda confusing cause i always saw circle notation as like O(x, y)
but i guess it makes sense its not talking about the center, thats just a way to identify the circle
That's fine dude even I was confused there for some time
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hi, can anyone help me understand this concept? its factoring quadratics, ive tried different explanations but none of them really make sense to me.
i promise im in college 😓 i just have difficulty understanding formulas
,rccw
for this particular case I would just have computed the roots
otherwise it's about guessing and training
lol with such an unclear explanantion i dont blame you for not understanding
yes exactly lol
im mostly confused on how to get the last two terms on the last step
i dont really understand where the 2 and -8 came from other than the -16, and if thats the case whats the point in multiplying the first and third number 😓
do you know about the complete the square method?
i think this one is easier for you to follow
would that work if its not an equation?
it works for most of the quadratics
so take the quadratic $9y^2 - 18y - 16$ as what it said
1 divided by 0 equals Infinity
do you notice that $(3y)^2 = 9y^2$?
1 divided by 0 equals Infinity
the purpose of this method, is to make a square
and what is $(a + b)^2$ and $(a - b)^2$?
1 divided by 0 equals Infinity
if you can't remember the formula, then just distribute it all out
wdym?
what i mean is that
this method's purpose is to make a square, which is in form of $(a + b)^2 \pm c$ or $(a - b)^2 \pm c$
1 divided by 0 equals Infinity
and $(a - b)^2 = a^2 - 2ab + b^2$
1 divided by 0 equals Infinity
so the $3y$ here can act as $a$
1 divided by 0 equals Infinity
?
wait
3y acts as a
and we want 18y to act as 2ab
notice that 18y = 2 . 3y . 3
so b can act as 3
since we only need b^2 left, we can seperate -16 into 9 - 25
so it should be something like
$(3y)^2 - 2 \cdot 3y \cdot 3 + 9 - 25$
1 divided by 0 equals Infinity
turns into $(3y - 3)^2 - 25$
1 divided by 0 equals Infinity
do you get what i mean now?
not really
its not the correct answer and im guessing thats why i have to use that formula
wait
that's not the answer yet
now do you know the difference of squares?
if you are confused about the formulas
try to discover why they are true
for example: $(a + b)^2 = a^2 + 2ab + b^2$, why?
because $(a + b)^2 = (a + b)(a + b) = a^2 + ab + ab + b^2 = a^2 + 2ab + b^2$
1 divided by 0 equals Infinity
the same reason applies for $(a - b)^2 = a^2 - 2ab + b^2$
1 divided by 0 equals Infinity
that is one way to remove your confusion of the formulas
they exist because they have proven it
@fervent burrow Has your question been resolved?
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ummmm
no
Also using an llm to scam is pathetic lmfao
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huh
💥
Bars
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Find the number of ways in which two small squares can be selected on the normal chessboard if they are not in same row or same column.
My answer is 64*49 , but idk the answer is given 32X49
You overcounted each position twice
Yes , that's written int he solution......
But why
I mean normall
y
when I use principle of counting I don't think of overlapping
Why for this specific case I have to
Think about how you picked your squares
Yes....... i had 64 choices for the 1st square and for each correspond square I had 49 choices