#help-39
1 messages · Page 182 of 1
Arnavutköy
okey
so $(1+\sqrt{3}i)=(2,\frac{\pi}{3})$
Arnavutköy
what is $(1+\sqrt{3}i)^7$ then equal to in terms of polar coordinates?
Arnavutköy
,, (1 + \sqrt{3}i)^7 = 2^7 \left(\cos\left(\frac{7\pi}{3}\right) + i\sin\left(\frac{7\pi}{3}\right)\right)
no no need to do it that way
use de moivres again
what is $(2,\frac{\pi}{3})$ to the power of $7$?
Arnavutköy
we simply raise the magnitude to the power
but we only multiply the argument/angle
so what do we get
I applied demoivre but maybe I messed up
um yeah let me tell which mistakes you did
Bro is helping 5 ppl at once
idk, it should be 2^7
What a 🗿
- You should raise $2$ to the power of $7$
Arnavutköy
- It was $\frac{\pi}{3}$, not $\frac{\pi}{4}$, so you should change the $4$s to $3$s
Arnavutköy
my bad yeah
938c2cc0dcc05f2b68c4287040cfcf71
it makes me feel productive which makes me feel less guilty for procrastinating finals studying
Ah
@stoic imp Has your question been resolved?
oh sorry i forgot
um we can simplify $\frac{7\pi}{3}$ to $\frac{\pi}{3}$ as it cycles $\pmod 2\pi$ right?
Arnavutköy
how so?
you said to not use the +2kpi
well we can simplify still in terms of $2\pi$
Arnavutköy
but we don't need to "keep" track of all possible values
okay
,, (1 + \sqrt{3}i)^7 = 2^7 \left(\cos\left(\frac{\pi}{3}\right) + i\sin\left(\frac{\pi}{3}\right)\right)
938c2cc0dcc05f2b68c4287040cfcf71
Arnavutköy
,calc 2^7
Result:
128
Do you know what $\bar{z}$ is in terms of polar coordinates if $z=(r,\theta)$
Arnavutköy
in terms of magnitude the conjugate has same magnitude
yes
in terms of argument idk
here ill tell you the argument becomes negative
basically imagine this on the polar coordinate grid
we get the conjugate by flipping over the x-axis right?
is hard for me to imagine, but the conjugate of
a + bi is a -bi
and for a - bi is a + bi
the imaginary part is opposite sign
x axis is Real part and y axis is imaginary part
idk if we flip over x axis, idk
I would need a drawing
yeah ill just tell you it is $(r,-\theta)$.
Arnavutköy
Arnavutköy
,w arctan(-sqrt(3))
yeh
okay, so multiplying these together, we have that $(1+\sqrt{3}i)^7\bar{z}^2=(2^7r^2,\frac{\pi}{3}-2\theta)$.
Arnavutköy
Therefore, we have $(64r^3,3\theta)=(128r^2,\frac{\pi}{3}-2\theta)$.
Arnavutköy
Can you find $r$ and $\theta$.
Arnavutköy
π/3-2θ? how did that happen
when we multiply complex numbers the argument gets added
here, remember this golden rule.
multiplying numbers multiplies the magnitude, and adds the arguments
good
okay, so when we set the LHS and the RHS equal in terms of the polar coordinates, we got that $(64r^3,3\theta)=(128r^2,\frac{\pi}{3}-2\theta)$. Can you solve for $r$ and $\theta$?
Arnavutköy
Arnavutköy
can you write $z$ now as a complex number?
Arnavutköy
your answer will contain sin and cosine
,, z = 2\left(\cos\left(\frac{\pi}{15}\right) + i\sin\left(\frac{\pi}{15}\right)\right)
938c2cc0dcc05f2b68c4287040cfcf71
there is actually a few other solutions
remember how i told you that you could ignore the $2\pi$?
Arnavutköy
well now when we are setting these as equal, it isn't exactly true that $3\theta=\frac{\pi}{3}-2\theta$.
Arnavutköy
It is possible that they are a multiple of $2\pi$ off
Arnavutköy
what to do then
So suppose that $3\theta=\frac{\pi}{3}-2\theta+2\pi k$
Arnavutköy
Then $5\theta=\frac{\pi}{3}+2\pi k$.
Arnavutköy
Therefore, we get that $\theta$ can be $\frac{n\pi}{15}$, where $n$ can be $1,7,13,19,$ or $25$
Arnavutköy
how so?
plug in $k=0,1,2,3,4$
Arnavutköy
after $k=5$, you see that it repeats
Arnavutköy
what happened with pi/3
the $\frac{\pi}{3}$ case was when $k=0$. In this case, we got $\frac{\pi}{15}$.
Arnavutköy
ok I see
,, \theta = \frac{\pi + 6 \pi k}{15}
938c2cc0dcc05f2b68c4287040cfcf71
k = 0 ==> π/15
k=1 ==> 7π/15
k=2 ==> 13π/15
k = 3 ==> 19π/15
so what?
,, z = 2\left(\cos\left(\frac{\pi + 6 \pi k}{15}\right) + i\sin\left(\frac{\pi + 6 \pi k}{15}\right)\right)
938c2cc0dcc05f2b68c4287040cfcf71

yes this is right
Number 4?
<@&286206848099549185>
use a new help channel
you can just close this one
is this all z?
yes it is
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not gonna lie. How do you find the solution for the left one
x² + 6x + 9 = x² + 8x + 16
ohh
so just 2x = -7
my bad
Yea no worries
Yes
Bc the x² cancels out
Also if you put it in the equation, it becomes (-½)² = (½)²
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this is my worksheet and I have a question ig about the topic
converting coordinates?
so I was doing it and I understood the lesson, and I thought it was just asking me to put the normal equations into polar equations
yeah so I got number one correct, but then for number 2, I did rcos(theta) + rsin(theta)=0
u want r on oneside
k
ohh ok
good?
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how does one analyze functions of the same "family"?
what do you mean same family?
not really
the function is pretty much the same besides the parameter
which is in this case 1,2,3
so they will have similiarities
whihc are calculateable
I'm not sure how thouhg
ohhh
for example ax + b
it has some common properties between different values of a and b?
yes
lile 3x + 1 and 5x - 7?
yep
with analyze I mean calculate all extreme points, concavity and stuff like that
oh
js follow the rules that you know
abt extreme points or concavity or all that
there isnt much to do other than applying your formulas when analyzing functions
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Hello!!! Im studying for my calc final rn...but I don't understand 13c. How does the answer key get the bounds [-2,-3] and why is it being subtracted?
@topaz pasture Has your question been resolved?
the idea is that for y between -3 and -2 the region is bounded only by the curve y=(x+2)^2-3
and the area of the sub-region bounded by that curve and y=-2 is given by this integral
this other integral corresponds to the area bounded between y=-2 and the two curves in the statement of the problem
these two curves meet at y=6
ooooooooohhhhhhhhh
bro u made my brain fire like mad
neurons are ocnnecting
ok
ooooooooo bc under -2 there is only the curve
there isnt the linear line
wow
math sometimes is wild
ty tho
have a good one 🙂
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wait I still confused on one part
why does the other integral not include the other branch of the equation
like the problem got split into -2-(y+3)^1/2 and -2+(y+3)^1/2
only the second equation used?
because x=-3 and x=-2 is still under the curve -2-(y+3)^1/2
@topaz pasture Has your question been resolved?
no? they're integrating the difference between both branches between y=-3 and y=-2
yes but the curve -2-(y+3)^1/2 still applies past y=-2
shouldnt the branches be (6,0) and (0,-2) and (-2,-3)???
hmmm yes I agree with this
so maybe there's a typo here
because for (0,-2) the curve -2-(y+3)^1/2 still applies in the eqaution right?
Am i tripping?
like it's making sense right?
thank you for ur help though...
I'll prolly keep this open for a little bit longer to see if anybody else thinks I'm doing something wrong
nevermind, I checked with desmos and this seems correct
could you explain just a little bit more
the branch x=-2+(y+3)^1/2 is the red curve here, while the blue line is x=(y-4)/2
note that the y and x axis labels are swapped here
comparing to this picture you could think of x=-2+(y+3)^1/2 as being the "right side" inverse branch since it has a bigger value of x
wait let me explore a little bit as well
ooooooohhhhh ok i seee
because the equation x=-2-(y+3)^1/2 ends after y=-2
hmmmmmm thats smart
i see i see
tysm for ur help
have a good one\
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I'm reviewing my assignments for AP Calc and currently working on derivatives of implicit realtions.
i cant quite read 4 properly
for these things you need to use the product rule, and chain rule
did you write y'(e^x)(1)=0?
@knotty prism Has your question been resolved?
@regal herald yes
Oke that makes sense
How would I setup for number 3
Would I separate x and natural log y?
So I would take the derivate of x and then the derivative of natural log y
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I meant the product rule lol
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@knotty prism Has your question been resolved?
What would the derivat9ve of natural log y be?
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A circle is circumscribed about an equilateral triangle with side lengths of $6$ units each. What is the area of the circle, in square units? Express your answer in terms of $\pi$.
938c2cc0dcc05f2b68c4287040cfcf71
sup
hi, can I get some help
yea its been a while since i did this tryna remember how
?
let the radius be r
and the height of the equilateral triangle be r+h
you can see 2 right angled truangles
so use pythagoras
u got the answer for this?
i got one but i wanna see if im right
before i explain how i got it
I am still trying to see what trickery ashley made
ashy... but ashley sounds great
i got 2 sqrt 3
for area?
i got 4cos30 for r
wait no
12pi
12 pi
yeah same
alr i guess my way works
oh trig works better
ye sqrt3/2
cos the angles are nice
yup
can i get some help down here?
oh
yea
im writing it out so u can see
didnt use trig here, but i can do it that way if u want
its just the matter of using pythag vs trig to find x and h
,rotate
fyi, sqrt(27) can be simplified to 3sqrt(3), which then makes r 2sqrt(3)
then once u square it it becomes 4*3 which is 12
well i just split it into three
the very middle point
to the corners
as its a triangle, it divides by 3
how so?
its an equaliteral triangle
so all the "bases" are 6
and the "heights" are from the corners to the middle of the triangle
hence all 3 have the same area
which combines into the big triangle
x is height of the shaded sub triangle
yes
yellow part helps you find height
how is yellow related with red
if u draw a circle around yellow
it becomes red
i didnt write 6 beside the sides
but its the same thing
its so hard to explain online lmao
how did u figured the height?
look to the right
ahh Pythagoras
ye
👍
also its better if u keep things exact
and try without calculators when possible
cause in uni exams
i dont have a calculator D:
yes in pi
lmao i meant with sqrt27
you are Viktor, u got it
☠️
alr lets close this lol
.solved
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Why must x by a n-dimensional vector of variables? Or, why can we not multiply matrix a by constant numbers?
@unreal stream Has your question been resolved?
@unreal stream Has your question been resolved?
@unreal stream Has your question been resolved?
You can multiply matrices by constants
c * A is the matrix A with all its entries multiplied by c
Top of page 2
https://math.mit.edu/~gs/dela/dela_5-1.pdf
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Help with question 30 please
Please ping
,rotate
since it gets cut apart at x=1, I would try to make sure it's continuous at that point and has the same slope at that point by making sure the values are the same for both functions there
@sacred hollow Has your question been resolved?
Thx
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I want to confirm that the following statement from Google's AI is correct,
You're absolutely right. While the traditional row echelon form and Gaussian elimination methods primarily deal with real numbers, the concept of linear equations and systems can be extended to the complex plane.
In such cases, the coefficients and variables can be complex numbers. The techniques for solving these systems are similar, but the calculations involve complex arithmetic.
However, the fundamental principles of row reduction and the concept of pivot elements still apply. The pivot elements can be complex numbers, and the row operations would involve complex arithmetic.
It's an interesting extension of linear algebra, and it has applications in various fields, including signal processing and quantum mechanics.
The 'You're absolutely right.' statements of it are kinda suspicious.
It's very submissive, this llm.
this is true
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Prove that (sinv)^2+(cosv)^2=1. Justify clearly
We can prove using pythagorean theorem and then extend to all reals
How so
I have no idea tbf
Ok so assume 0 < v < 90
Ok
Then we can construct the right angle triangle where one angle is v and then it definition of sin and cos
Btw did they set a bound for v
No information other than that given
Can as well
Oh ok
Have you learnt that sin and cos can be extended to all real numbers
Dont think so
Then all we need to do is prove for 0 < v < 90
Okay
Add in the equal signs somewhere ig
Yes
...
Try just multiplying it and seeing if it's familiar
Hey no need to think so much
We get opp^2 + adj^2 = hyp^2
Is this familiar?
Yea
What is it
Pythagoran theroem
We're done at this step alr 🙂
Yes
🙂 there is a version to extend to all real numbers which is that hard
I rly appreciate it
Im not that far along yet haha
Np 
Cya
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the unit circle
(sin x, cos x) is any point on the unit circle
Yep
using pythagoras shows sin^2 x + cos^2 x is the radius squared
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which is 1
oops
💀
,close
.close
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Prove that the nth roots of unity form a cyclic subgroup $C^{\cross}$ of order n
ƒ(Why am. I here)=I don't Know
Kind of not sure where to start
I have to show that the roots have a generator
that's it, right
yes
hmm, $z^n=1 \implies z = 1^{\frac{1}{n}}$. It then follows that $z^2 = 1^{\frac{2}{n}}$ is also a root for $1^{\frac{2}{n}}^2=1$ and so on. It thus forms a cyclic group.
ƒ(Why am. I here)=I don't Know
hmm, $z^n=1 \implies z = 1^{\frac{1}{n}}$. It then follows that $z^2 = 1^{\frac{2}{n}}$ is also a root for $1^{\frac{2}{n}}^2=1$ and so on. It thus forms a cyclic group.
```Compilation error:```! Double superscript.
l.1422 ...}$ is also a root for $1^{\frac{2}{n}}^
2=1$ and so on. It thus fo...
I treat `x^1^2' essentially like `x^1{}^2'.
Preview: Tightpage -1310720 -1310720 1310720 1310720
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(./796939110815629322.aux)
***********
LaTeX2e <2023-11-01>
L3 programming layer <2023-11-01>```
please dont write it like that
which number is 1^1/n supposed to be
the whole point of nth roots of unity is that there are n of them
not just one
a root of unity
which root of unity
the first, nth root of unity
what is the "first" root of unity
From $1=z^n$, we get that $z = 1^{\frac{1}{n}}$. As $z^n$ is 1, this tells us that $1^{\frac{1}{n}}$ is a root of unity. we also find that $z^a = 1^\frac{a}{n}$ is a root of unity, for $a \in \Z$ as $ {1^{\frac{a}{n}}}^n = 1^a=1$. This tells us that $1^{\frac{1}{n}}$ is a generator and that the set of the roots of unity forma. cyclic group.
ƒ(Why am. I here)=I don't Know
I just told you not to write 1^1/n
Then what do I write
well what do you mean
$\omega_{n}$ like a normal person
如月あやみ Kisaragi Ayami
just define it in the beginning
ƒ(Why am. I here)=I don't Know
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whats theta
The angle the complex number makes with the x-axis
j 2π/n where j ranges from 0 to n-1 and n is the root that we're determining
but which of this gives the "first" root
j=0
yes
and then we move anti- clockwise
hmm, no
they are powers of $e^{ \frac{2 i \pi}{n}}$
ƒ(Why am. I here)=I don't Know
ok
so we set $\omega_n = e^{\frac{2 i\pi}{n}}$ and you are claiming that $\omega_n$ generates the group of $n$-th roots
Denascite
why
yes
wdym
$w_n=z$, so $w^n=z^n=1$. Similarly, $w^{2n}_n=z^{2n}=1^2=1, w^{an}_n=1^a=1$
ƒ(Why am. I here)=I don't Know
does this work?
that shows that powers of omega_n are also nth roots
it does not show that every nth root is a power of omega_n
how do I do that
I mean I can get n roots this way, and by the fundamental theorm of algebra , there are n distinct roots
Can I have a hint
yes
exactly that
(well you dont need the full fta, you only need that there are <=n roots)
so that justifies that this is a cyclic sub group
now I have to prove it's of order n
that part should be obvious
yeah, it kind of is
It's of order n as e^{2 iπ}=1
and not true for any integer less than n
thanks
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horizontal tangents occur when the derivtive is 0
but isnt the deriv x^1/x(1-lnx/x^2)
yes
how did he only use 1-lnx
oh
can you explain this one too
why did they use ln
shouldnt the deriv be 2.847 t(1.0072)^t-1
actually i do remember this being before we learned the power rule
i forgot how u get the derivs without that
$$\frac{d}{dx} a^x = a^x \ln a$$ where a is any constant
JustToPro
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how do they take the derivative here
differentiating a sum is the same as summing a ton of derivatives
so you can just $\frac{d}{dt}$ the inside and $pq^{n-1}$ is obviously a constant in the $t$ world
如月あやみ Kisaragi Ayami
if you do it $r$ times, then first of all, obviously your $t^{n}$ has become $t^{n-r}$ due to repeated use of the power rule. And secondly, you're gonna end up with a bunch of trailing coefficients on the $t^{n-r}$ term because everytime you differentiate you take the exponent and put it in front. That long train of coefficients looks like $n(n-1)(n-2)(n-3)\cdots(n-r+1)$ which is equivalent to $\frac{n!}{(n-r)!}$
如月あやみ Kisaragi Ayami
everything makes sense to me right now except how n(n-1)(n-2)......(n-r+1) is equal to that permutation could u maybe elaborate on that?
$n(n-1)(n-2)\cdots(n-r+1)=n(n-1)(n-2)\cdots(n-r+1)\times\frac{(n-r)(n-r-1)(n-r-2)\cdots(2)(1)}{(n-r)(n-r-1)(n-r-2)\cdots(2)(1)}$
如月あやみ Kisaragi Ayami
$n(n-1)(n-2)\cdots(n-r+1)=\textcolor{red}{n(n-1)(n-2)\cdots(n-r+1)}\times\frac{\textcolor{red}{(n-r)(n-r-1)(n-r-2)\cdots(2)(1)}}{\textcolor{green}{(n-r)(n-r-1)(n-r-2)\cdots(2)(1)}}$
如月あやみ Kisaragi Ayami
the red parts form $n!$ and the green parts form $(n-r)!$
如月あやみ Kisaragi Ayami
you could see this more easily with a small example
$7\times6\times5\times4=7\times6\times5\times4\times\frac{3\times2\times1}{3\times2\times1}=\frac{7\times6\times5\times4\times3\times2\times1}{3\times2\times1}=\frac{7!}{3!}$
如月あやみ Kisaragi Ayami
makes sense?
HOW did u come up with this man
yes thank you so much
nice
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Here’s the question and it’s a really tricky integral question
Here’s my solution please verify it for me and it took me 3 hours for the solution
@rough forge
This one ChatGPT won’t even be able to give hint (I never used ChatGPT to solve questions for me but generally speaking I do ask directional questions like how to approach certain questions) but this one it won’t get me a hint 😭
Do you get the same answer if you find the area of the full petal and multiply by 6 instead of half a petal and multiply by 12
,w solve cos(3x/2)=0
Take eg. n=0,-1 and get two values for theta
I just got frustrated yesterday, and I decided to do small analysis on each blooms so I slept after setting up the boundary and I computed the integral today
Is the answer correct though and how to find the region in general?
The tricky part is if I do integral over [pi/3, 2pi/3] which seemed to be a full blown, the area for the petal will be omitted which is bizarre right?
This is almost tricky for trickiness
Only when you do integration at the exact range of half piece you get the area of half of the blooms and its parametrized so it’s hard to find where the other half of bloom is
The question you can just restrict it easily the boundaries though maybe you can rotate the curve but it will either way take long time, can’t believe the prof thinks of anything like this
<@&286206848099549185> can you guys help me with verifying the sol and is there easy way doing such integral?
<@&286206848099549185>
hm
so my method would be to integrate from theta = 0 to theta = pi/4 and multiply by 12
so 6* integral from 0 to pi/4 cos^2(3/2x)x dx
so this
which is
Why though? I wonder the reasoning and can you teach me the method? Because I will still need to justify my reason though
I just want to know every single method for tackling this type of integral
The shaded petals or unshaded?
unshaded
But why 0 pi/4 will have half of unshaded petal please teach me 😭😭
That’s genius !!!
this is
That’s brilliant you saved my life 🥰🥰🥰🥰
thanks
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i have to find this limit n->infinite
the answer should be -1
but i get this:
wait sorry
what i get is 0
but the answer should be -1
yes
this is indeterminable inf-inf
but this is the algorithm that we learned
yes
and down is radical a + radical b (a and b being what i have)
oh
square root not radical*
those are these square roots but it was too long to write:
also with + not -
so i can reduce the square roots
okay i see
yippee
let me fix it and ill send a picture
alright
nicely done
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here, can't you just set the index to 0 to infinity, since n=0 is just summing up 0?
so then you would have something like this
e.g. if you set x = 1 in the series, you’d effectively be dividing by zero (from the (x-1)^{n - 2} etc) and of course that’s very bad 
oh I see, so you can only change the index like that when it is a power series where its just x^n, xo=0
but they did that here in this example?
oh wait i meant to send this earlier, the wifis not too good
For this one, because you’re multiplying by “an appropriate power of x”, it doesn’t really matter as much cause you won’t end up with negative indices after simplifying it 
i see
but generally if you have the form (x-xo)^n, where xo is not 0, then you would have to keep indices the same (or sub t=x-1) or smth like that
to solve
wait but theres an error here??
They reindexed to have the series start at n = 1 instead, then noticed that you don’t get any dividing by zero issues, and that n = 0 gives you an “output” of zero (hence their comment above that bottom line)
ahh i dont like this reindexing stuff, its making me confused
im gonna try another method, ill send a picture in a bit
before I keep going, can I do smth like this?
@merry carbon
You can do it like that and remove the “lower” terms sure 
ok!
so then I have to say for n>=2
i would get the same answer?
im gonna continue and try it out, thank you!!
It should be at least equivalent, I would think 
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For clarity this is not a real quiz 💀 its a practice for my finals but um how do I use the vertical line test 😭
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can you anser this?
σ (n) ≤ Hn +ln (Hn)eHn
Where n is a positive integer
Hn is the n-th harmonic number
σ(n) is the sum of the positive integers divisible by n
For an instance, if n = 4 then σ(4)=1+2+4=7 and H4 = 1+1/2+1/3+1/4. Solve this equation to either prove or disprove the following inequality n≥1? Does it hold for all n≥1?
$\rho(n) \leq H(n)+ln(H(n))*e^{H(n)}$?
Kai The Cat
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what
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HI PLZ ZHEJLP
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Prove that every subgroup of a cylic group is cyclic. Do this by working with exponents and use the description of the subgroups of $\Z^{+}$
ƒ(Why am. I here)=I don't Know
Why does the last part make a difference
reads more like a hint to me
Firstly, as we know this is a sub-group(H), we have the identity element say $1$ in the subgroup, it has inverses so if $a \in H$, then $a^{-1} \in H$ . Lastly, we know if $a \in H, a^n \in H$, then $a^{n+1} \in H$
ƒ(Why am. I here)=I don't Know
As all the elements are of the form $a^m, m \in \Z$, the group is cyclic
ƒ(Why am. I here)=I don't Know
maybe what I would do is consider the morphism $\bZ\to \langle a\rangle$, $m\mapsto a^m$ and work from there
derivada.schwarziana
I haven't done morphisms yet
oh alright
I suppose I just use the defn of a cylic group then
yet you know that the subgroups of $\bZ$ under addition are $n\bZ$ for some $n$ right
derivada.schwarziana
yes
the idea is that you want to look at the n dividing the order of the group <a>
I suppose a proof by contrapositive would work particularly well here
er in the finite case anyway
(an infinite cyclic group is isomorphic to (Z, +) though)
hmm
yeah
but what about contrapositive, that would work well, right
if the sub group is not cyclic, then the group is not cyclic
that might work yes
If the subgroup is not cylic, there is atleast one element in it that's not a power of a generator, thus, the group isn;t cyclic either as there is one element that isn't an power of a genator either
right, more precisely if some subgp. H isn't cyclic there exist some a,b in H such that a is not a power of b
I think this is enough?
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i'm not so sure
integers mod 4 under addition is cyclic but 1 isn't a power of 2
that's right, I wasn't so sure of the claim tbh
I guess this works under multiplication?
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✅
what are the elements under multiplication?
a^{-1},1.a, a^2 \dots
i mean
what is integers mod 4 under multiplication?
1 is an identity
0 doesn't have an inverse
0,1,2,3
so 0 can't be in it
so 1,2,3,4
4 is 0
yes, I know
well 4 doesn't have an inverse either
no
yes
So my proof covers groups under multiplication
uh
I now have to cover groups under addition?
you have to cover groups under any possible operation
so a contrapositive proof won't work
I mean I just have to show there is one element that isn't the power of a given generator
right
i'm not sure how to do it
i'm thinking of saying something like
G is generated by some element, call it a
then all elements of H are expressable as a^n for some n
i want to take the gcd of these n's
or something like that
why is what I've done wrong
this seems sus
for example
uh
how do you know it's not the power of a generator in G that wasn't in H?
wdym
see when they tried to make your statement more rigorous it fell apart
how has it fallen apart
H isn't cyclic if there does not exist an element g in H such that every element of H is a power of g
if some subgp. H isn't cyclic there exist some a,b in H such that a is not a power of b
this fails to imply G isn't cyclic
yes
ye i had an idea
hmm?
H has elements of the form a^n
the element with the smallest such n should be a generator of H i think?
uh but you'd have to reduce the n's mod the order of G

doesn't matter
pick an element of H which can be expressed as a^n for the least possible n
Okay
i still feel a bit stuck
same
how do you know you can though
n does not divide m
yeah that's what i meant
too many letters man
m = qn + r, r < n
a^m = a^qn a^r
but a^qn is in H since a^n is
so a^-qn is in H
so a^r is
but r < n
contradiction
yes
n was assumed to be minimal
i like it
hmm
makes sense
Thanks
Got it , can I close this now
wait
I'm still not sure I get why my method is wrong
If I make an. argument about the group, it should be good, right
because your arguments are always good? heheh

what do u mean
I mean If I add an argument that connects the subgroup to the group, my argument should work
right
yeah if you can show H not cyclic implies G not cyclic, that would suffice
If G is not cylic, there's atleast one element in it that is not a power of the generator from G, but this element is also in G, so G isn't cyclic
u started with G, you meant H right?
yes
sorry for pestering you with my solution
it's fine, i enjoy it
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help please
Use $\frac{a}{b}\cdot\frac{c}{d}= \frac{ac}{bd}$
how?
riemann
riemann
Inverse sine and cosine don't have the domain you're looking for.
You sometimes have to add some angle to the inverse trig value to get the right angle
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I'm just lost like do I have to do 1/3(2x-5)
are C and D supposed to be the midpoints?
yea
so PC and QD are the medians
Yes
yes the centroid
ok, i will tell you that there is a theorem
that the centroid lies 2/3rds the way along all medians
if you want to prove this fact
you can prove it using coordinate geometry
using the fact that the centroid is the average of all coordinates
so essentialy this means that $\overline{QG}=2\overline{GD}$
Arnavutköy
why would you do 2 (GD) and not 2/3 (GD)?
it would be $\overline{QG}=\frac{2}{3}\overline{QD}$
Arnavutköy
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Can anyone explain this step?
oh they just rewrote $\cos^3 = \cos \cos^2 = \cos (1 - \sin^2)$
south
and then you have a -1 * -1 * 1/(sin^2 theta) left to integrate
1-sin^2 = cos^2, so the first integral was just rewriting cos^2 and then they brought the -1 factor outside the integral so -1/3 -> 1/3 because now it’s + 1 instead of -1
there is a minus sign in front of the entire integral
Ooh thanks Is this a common trick😢 cuz it's really hard to come up with
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Why does this go to -1/2
Shouldnt it go to 0
Limit is towards +inf btw
Of x^2-x(sqrt(x^2+1))
I multiply by conjugate
you got $\lim_{x\to\infty}-\frac{1}{1+\sqrt{1+\frac{1}{x^2}}}$ from what i can see?
Skissue ping4response
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Ye
when it goes to infinity, 1/x^2 goes to 0
@wary heron Has your question been resolved?
Maybe
yh the answer is -1/2
Maybe
!done


