#help-17
1 messages · Page 165 of 1
is 4 and 6 are at ends of a curve does that make them both mins?
4 is a min but not 6
yep
so 0 and 6?
yeah
but isnt there only one global maximum?
yeah so that’s why we need to compare them
we need to find what F(0) and F(6) is, and see which is greater
putting them into the integral equation?
yep
we don’t really need to antidifferentiate it
we can just use the graph to calculate the area
how would I do that? does the 0 annd 6 go into the x and the t? or jsut one of them?
y0shi
thats what I was imagining but I dont know what to do with that
well if we have the lower bound and the upper bound as the same number
the integral always evaluates to 0
regardless of what f(t) is
basically $\int_{a}^{a}f(x)dx=0$
y0shi
that makes sense but what about tthe 6
so we need to look at the graph above
there is a circle
and a triangle if we go from 0 to 6
we need to get the area of each and then add them together
remember that anything under the x axis would be negative
making 0 the Maximum
yep you got it
remember when it asks for the maximum, we always use the y value
not the x value
phew lol thank you so much ill write it all down and practice it a bit because I never whould have gotten there
but in this case they’re the same so it doesn’t matter
yw!
okay okay
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I cannot seem to solve this problem at all
i don't even know where to begin
we can do triangulation here
we are given 2 angles and a side
so we can use sine law
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i'm not sure how to find out the bounds for the integral. any help?
is it polar? i'm not really sure when to use cartesian and when to use polar
thats the entirety of the question, i thought we had to freedom to choose the order of integration
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How do I write this function interms of y
Is it even possible to isolate x?
I don’t think so, check x=8 and x=-8, unless there’s a condition on x, y can take multiple values for the same x
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I know what it's asking
I'm just not getting the right answer
I could go about this the long quotient law way
but instead I used derivative shortcuts
to get
$m=x^2-5+\tfrac{4}{x^2}$
Remlis
Remlis
there seems to be a way to solve for x
but I just don't know of it
$5=x^2+\tfrac{4}{x^2}$
Remlis
$5=x^2(1+4x^{-1})$
Remlis
mulitply the equation by x^2
and then let x^2=t
then it's just a simple quadratic
$5x^2=x^4(1+4x^{-1})$
Remlis
a useful strategy is often to turn an equation like this into a polynomial
$5t=t^2(1+4\tfrac{1}{t^2})$
Remlis
Remlis
Remlis
Remlis
Remlis
$$t=4$$
$$t=1$$
Remlis
$$x^2=4$$
$$x^2=1$$
Remlis
$$x=2$$
$$x=1$$
Remlis
yajat
Remlis
also just check if you're getting m=0 by putting all 4 solutions in this equation
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Don’t get
Try multiplying those two matrices
U get I^2 - A^2?
Yes, and what’s A^2
0
So?
Ok so ur left with I^2 uhh
And what’s I^2?
Mmm there’s some theory im missing
Yes
What so does that mean I^3 - I?
In fact, any power of I is just I
Yes
I thought that only applied to other things
1n=n1=n
Didn’t realise it applied to itself
lol
How would u know to multiply them in the first place
Didn’t cross my mind
And like why do u, why do u care if it equals I
Like i get it i just don’t get why
It means that they are inverses of each other
Well, (a+b)(a-b)=a^2-b^2
And the property we’re given tells us about A^2
So it’s pretty intuitive
Ohhhhhh
Shit yeah
Hm. So if you multiply two things and get I they’re always teh inverse of each other?
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What is the formal defintion the two sides of an open sentence?
3x + 3 = 5x - 3
I was thinking of just saying the left side of the equation but I was wondering if there was a better definition to describe it
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Did I do this correctly? My friend got a different answer so I want to be sure.
@austere plover Has your question been resolved?
<@&286206848099549185> :nyoron:
@austere plover Has your question been resolved?
@austere plover Has your question been resolved?
<@&286206848099549185>
You can substitute the values of u,r & t for what they’re equivalent too and then differentiate like that
I did that #help-17 message. Just want to make sure the answer is correct
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du/dx looks right. I just did it and got the same answer
@austere plover
Wait, no scratch that
🫠
Lol

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Can someone just confirm that what I did to get the answer was right?? The part above the red arrow is just the right side of the product rule
u seem right
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Ok so i need to create and equation that gives the volume of water in the troph based on the current water level x. I think i figured it out but it just seems wrong so was after some help.
@merry umbra Has your question been resolved?
seems correct
ok well thats good new it just felt wrong to be doing sin(cos^-1())
but in the final answer u need to put parentheses around the area of segment B
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nah, just because u are dealing with area of sections of a circle, thats why its kinda off
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!status
What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
1 ig
2w + 2L = 2000cm
wait what
?
where did you get 2000 cm
perimeter of the pool is 20m
oh ok
per of pool is 20m and thats w+w+l+l
i was thinking of doing something along the lines of (150+w) x (150+l) = 4000
that sounds about right
re arrange your equation in terms of either length of width your choice so you are only dealing with 1 unknown
you mean instead of 2w+2l = 2000
2w = 2000-2l?
ye
then divide by 2
so w = 1000-l
then wherever you have to use w just substitute 1000-L
eg 2w + 2l = 2000
would be 2000 = 2(1000-L) + 2L
yes because you need to use the information in the rest of the problem to create a new equation
I'll try (150+w) x (150+l) = 4000?
here you go @zealous hill
oh wow
now you know lw and l + w
now substitute for w = 10 - l
l(10-l) = 22.75
10l - l^2 = 22.75
l^2 - 10l + 22.75 = 0
or you can multiply by 4 to make it easier
4l^2 - 40l + 91 = 0
you should get pretty normal answers
what are you getting
what does the 2.25 mean?
i just expanded (1.5+l)(1.5+w)
1.5 * 1.5 = 2.25
ah
I re-worked it following your steps but in cms and it just messed up idk why
the150 x 150
did you convert 40 m^2 to 40 * 10^4 m^2
i did meters because cms is easy to mess up with
@zealous hill Has your question been resolved?
am here now
crazy to think all of this for just 6marks lol
l=3.5
w=6.5
however i didnt do the quadratic lol
I just trial and erorred my way into it
cause this part messed me up
ye right lol
so simple bruh why am i overcomplicating thingssss
but yeah thanks for the help
especially with the diagram n such
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help
complex numbers
although in that case you'll be getting an imaginary number
if you don't know how to solve x^2 = c i'm guessing you aren't doing complex numbers
im in grade 8 😭
yep
x^2 = -9 so no solutions (a square is always 0 or positive)
you probably won't learn that for 1-2 years though
nah id win
bro is not gojo
ew byjus
check if this is really the question
that company is in server debt
and used to downplay students in front of their parents
so that the parents would buy them the subscription
it is
@gritty hemlock
help me
x^2-36=0
how do
mostly it was like "your kids base is weak" which might be the case but then they proceed to teach the level which they are at instead of making the base strong
there is no way to teach this. this counts as common sense dude
probably just stick to helping people in the help channels, not random rants @gritty hemlock
x= +-6?
do you know difference of squares identity
no
bruh

but yes that is correct
dawg it's in 7th grade
🤫
$$a^2-b^2=(a+b) \cdot (a-b)$$
The Prophet Of The Damned
ooh ik that
Do you know how to find the zeroes of a factorised polynomial
I never got the chance before
@vast shale
no
Oh
$x^2-36=0\
x^2=36\
\sqrt{x^2}=\sqrt{36}\
|x|=6\
x=\pm6$
∫ooshⁱˣ
ok so not by name is fine
36=6^2 right
ye
what does the lines next to x mean
(x-6)(x+6 ) is the same as x²-36
ye
But the left is the factorised version
absolute value
so what will will x^2-6^2
((x-6)(x+6))
html hater
if you take an even root of an even power, since it's always positive but the expression inside the even power could have been negative, you need to add an absolute value
so
great now since that is equal to zero that means one if them is zero
so the first case becomes
x-6=0
and the second becomes
x+6=0
x^2=-81 not possible without complex numbers
k i get it
squares are always positive
or 0
it's on the edge
k
(dont dare you talk about complex numbers)
what? that has nothing to do with complex numbers
so surely there exists no number whose square is -81
ye
x^2=-81 has imaginary roots wdym
i'm talking about the squares being positive or 0 comment
bro is zoro
get back to the question
mb
dont get lost
kk
what was it again
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I need help with this question
This is my work. I don’t k is if it’s correct or not
he needs a unit vector
here n is just a normal vector
How can I get it
its the vector over its amplitude
Do I use AB or AC?
to get a unit vector in the same direction of the original vector, u divide that vector by its amplitude
which vector do u want to get its unit vector here?
The normal vector?
yes
How about the angle do you think it’s correct?
yep
Alright thanks
@frail maple Has your question been resolved?
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how did they go from here
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@open sundial
<@&286206848099549185>
sorry
I need to find the derivative of x^5ln(x) and what I've done is I've done the product rule f prime of x times g of x+ f of x times g prime of x and I got ((5x^4)(ln(x))) and I don't know if I should leave it like that or simplify by using the chain rule and then something else
but then i can't simplify cause I don't know how do do the chain rule with a function like that
the chain rule is the inside function evaluated at the outside function times the outside functions derivative
so the product rule is the derivative of f times g plus the f times the derivative of g right?
isn't that what I did?
that applies when there exists a product of two functions, this is just one function raised to a function power
you could try implicit differentiation
is the function: $x^5 \cdot \ln(x)$
Stephen
or is it not
x^5*1/x
one moment
what's up
i'm stuck
Stephen
$\frac {a^b}{a^c} = a^{b-c}$
Stephen
im not too sure what you're saying
the simplication was correct I did the math
x^4
yea, or u could factor out an x^4 and get x^4 (5lnx + 1)
yea no problem
alright gimme a while I'm gonna do the problem
i have to find where it's increasing and decrasing this was just a small part of it but I know how so thanks!
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so....How do I find where it's increasing and decreasing?
the previous problem? sorry again
where what is increasing/decreasing?
x^5ln(x)
consider the values of f'(x) as f(x) is increasing, decreasing, or neither
e.g. what can you say about the slope as f(x) is increasing?
so I got the derivative and it is x^4(5log(x)+1)
I need to find the critical numbers before I get the second derivative and I don't know how to do that
critical points are where f'(x)=0 or dne
but that's different from what you were asking initially
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I just want to check my answer
👍
you can always check your work by computing the inverse of the inverse lol
my bigger issues was if t-9 was right I googled a couple of similar answer and a lot of people were saying v-3 so I want to make sure using the t is correct
but if I reverse my x and y values then it has to be t and not v
why change to x and y 🤔
its just something I do..might be better to just stick with V and T
try to get comfortable with other vars if you can, you may come across more problems using different letters in the future
as far as independent vars go t is quite common actually
yeah I'm starting to notice that
I'll switch it to V and t before I submit it. Thanks for the help
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letters are universal anyway (coping hard)
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can someone help me solve this?
k
so for a i think u just plug in -1
and a
and then divide by a+1
right
so since f(-1) is 0
yep
it would be sqrt(a^2-1)/(a+1)
change in y over change in x
b was the part that was mainly confusing me
alright
we need to do some algebra
write down the expanded limit thing of this function
while you do that ill do the same thing but in latex
$\lim_{h \to 0} \frac{\sqrt{(x+h)^2-1} - \sqrt{3}}{h}$
hired
you can evaluate that limit using a conjugate
shit forgot about tha
t
but then how would you get rid of the square root in the denominator?
been a while since i did limits
why get rid of it? the conjugate is strictly positive >0, what do you care that it's there
h is the problem
yeah but we dont care about that
yeah but right now we're fixing the numerator
ok
we can't fix it all at once haha
lemme try that
ye
this is what i got
after doing that
what now
Also when someone sees this ping me so I get a noti
Huh?
How do you isolate h
So how do you do that
O
K
Thx
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Can someone pls help me get figure M onto figure N (I already know that you will need translation + rotation but i dont know the direction, units, and the rotation it goes.)
Translation goes: UP, DOWN, LEFT, or RIGHT ++++ AMOUNT of units. 90 degrees clockwise, 90 degrees counterclockwise, 180 degrees clockwise, or 180 degrees counterclockwise?
-fill in blanks
You can think of the problem in reverse: how to go from figure N to figure M, and then reverse the transformations that you get.
This helps because it's easier to start with the rotation: how should we rotate figure N to get a figure that is in the same orientation as figure M?
oh, well im using deltamath.com and in the examples it has it like that and i have to have it this specific way as it is in the examples. Going from translation to rotation. If thats what your saying?
No I'm saying that you can start with thinking about how you should rotate the figure and then translate it, because this makes it easier than thinking how to translate the figure then rotate it.
In the end you will write the transformations in the correct order of course.
No problem
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Can someone help me approach this math problem?
So, I have $u_{n+1} = \frac{1}{n+1} + \sqrt{u_n}$ a sequence and I know that $u_0 = a$ where $a \in \mathbb{R}^+$
I need to find
$\lim_{n \to \infty} (\frac{u_n - 1 - \frac{2}{n}}{\frac{1}{n}})$
How would you guys try to solve this problem?
We know that $\lim{n \to \infty} (u_n) = 1$
And that $t_n$ which is a special case of $u_n$ where $t_0 = 4$, has for limit when $n \to \infty$ the limit: $\lim{n \to \infty} (t_n) = 1$ and $\lim_{n \to \infty} (\frac{t_n - 1 - \frac{2}{n}}{\frac{1}{n}}) =0$
Smile!
@keen tangle Has your question been resolved?
<@&286206848099549185> Please
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is the region the tip of the cone??
i can't think it would be anything else but its not above the cylinder so im lost
i think its super simple and im just losin braincells but
👍
bounded below by the cone tip, above by the cylinder surface
it would look something like that right?
wait
lemme fix
like that?
i think they mean this?
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I have the transformations and everything but I don't understand how to apply them to these questions
@silk garden Has your question been resolved?
The first column of the standard matrix is where the basis vector (1, 0) ends up after the transformation
The second column is where the basis vector (0, 1) ends up
Does that help?
Not exactly
Like what am I supposed to do when I have both transformations
And also it says dilation, does that mean both a horizontal and vertical dilation?
Yes
A dilation is where all the directions get scaled by the same amount
Okay
Just see where each basis vector ends up
So then if I have both transformations as matrices
So for question a), where does (1, 0) end up after the two transformations?
You could also do it like that
Then just multiply them
First matrix goes on the right, second matrix goes on the left
The order of matrix composition is from right to left
Yes, so if A is the dilation matrix and B is the reflection matrix
It would be BA
Yes
Just curious, going about it like this would also yield the same answer as just multiplying the separate transformations right?
Yeah, they would both give the same answer
Okay, cause I think my professor may want me to do it the first way you mentioned
And I just wanna know if I'm getting the right idea with that
The reason why is that if you do this, you're actually multiplying by the identity matrix {{1, 0}, {0, 1}} in disguise
Yeah both methods are absolutely fine
I just prefer my way obviously
So I'm going 3[1,0] and 3[0,1] I get [3,0;0,3] and then I go -1[3,0] and 1[0,3] and get [-3,0;0,3]
?
@bronze osprey
Yeah so (1, 0) ends up at (3, 0), and then is reflected to (-3, 0)
(0, 1) ends up at (0, 3) and it is unchanged if you reflect across the y-axis (cause that's just x -> -x)
So yeah, the matrix with columns (-3, 0) and (0, 3)
So I don't technically multiply by anything doing reflections, it's just indicating a reflection
Yeah, well there is a reflection matrix also
It's $\begin{pmatrix} {-1 & 0} \ {0 & 1}} \end{pmatrix}$
Yeah I know there's a reflection matrix
south
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If you reflect across the y-axis
And yeah multiplying by this matrix will give you the same as doing each basis vector individually
Cool cool
And only reason I think I should do it the first way is because my second question in the homework wants us to check if each part is commutative
By multiplying the matrices
Right
No worries!
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@bronze osprey I'm sorry I have another question
In part c, I'm not sure how to apply the transformations to individual vectors
Right, so if you reflect (0, 1) across the line y = x, it becomes (1, 0)
You just swap x and y around
And then we have a reflection which is similar to what we did in part a
Yeah so my new vectors were [0,1] and [1,0]
Remember that the first column represents where (1, 0) ends up
Ah ok
Yeah I did the y=x reflection
And then after you do the reflection...
But it says the reflection is represented as [1,0;0,-1]
Yeah that's the matrix
Yep
$\begin{pmatrix} {0 & 1} \ {-1 & 0}} \end{pmatrix}$
south
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Ah I see I see

@bronze osprey On part d, I have my 45 degree rotation
$\begin{pmatrix} {√2/2 & -√2/2} \ {√2/2 & √2/2}} \end{pmatrix}$
✿ 𝓢𝓬𝓱𝓲𝓪𝓯𝓯𝓲𝓷𝓸 ✿
$\begin{pmatrix} {√2/2 & -√2/2} \\ {√2/2 & √2/2}} \end{pmatrix}$
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not set up for use with LaTeX.
See the LaTeX manual or LaTeX Companion for explanation.
Type H <return> for immediate help.
...
l.49 $\begin{pmatrix} {√
2/2 & -√2/2} \\ {√2/2 & √2/2}} \end{pmatrix}$
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$\begin{pmatrix} {sqrt2/2 & -sqrt2/2} \ {sqrt2/2 & sqrt2/2}} \end{pmatrix}$
✿ 𝓢𝓬𝓱𝓲𝓪𝓯𝓯𝓲𝓷𝓸 ✿
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Okay idk how to fix that
But I have this
I just don't know how to apply the y=-x transformation
✿ 𝓢𝓬𝓱𝓲𝓪𝓯𝓯𝓲𝓷𝓸 ✿
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@silk garden Has your question been resolved?
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Please help! I dont get it and my teacher haven't taught us anything. If you can explain please do! Thank you!
do you know what "similar" means in the context of geometry?
Yes
Similar triangles are triangle with sides proportional and angles congruent
When a line is draw from the right "corner" of a right triangle to the hypotenuse, forming a 90 degree angle, it creates two smaller triangles that are similar to the larger one
For question 5, Triangle XWZ is similar to triangle XZY
Oh so like the original triangle is similar to both the triangles formed?
the mean?
The middle line
oh i didnt look at those gimme a sec
Oki, thank you
ah ok
so if two triangles are similar, the ratios of the lengths of two corresponding sides are the same for both triangles
Ohh i get it now, thank you so much
the ratio of the length of the short leg to the length of the long leg is the same for all similar triangles
so for 19, 4/x= = x/16
and solve from there
alr glad i could help
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quick question
for leading coefficient test, how do we determine which way it falls and rises?
i dont have a specific problem im trying to solve, but rather just general info
for a polynomial, you have two main types of behavior
either the leading coefficient is odd, in which case it goes to -infinity on the left and infinity on the right (e.g., y = x)
or the leading coefficient is even, in which case it goes to +infinity in both directions (e.g., y = x^2)
if you have a negative sign in front of the leading coefficient that just flips the signs
Im gonna nap rq but can u give example of both scenarios?
for y = x^3 we follow the first scenario, it goes to -infinity on the left and +infinity on the right
for y = -x^3 it does the opposite, going to +infinity on the left and -infinity on the right
for y = x^8, it follows the second scenario, going to +infinity on both sides
for y = -x^8, it does the opposite, going to -infinity on both sides
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does a ring homomrophism send unity to unity?
Depends on which definition/type of rings we are talking about
For homomorphisms of unital rings, the unity is preserved
For homomorphisms of (possible nonunital) rings, the unity need not be preserved
I want to determine all the rings homomorphism between Z_12 to Z_30
I found the possible group homorphims,
i want to proceed from there
Does your definition of ring require unity?
it's abelian under addition and x is a binary operation which is associative and satisfy distributivity
non commutative and doesn't have unity
I see
Take the group homomorphisms that you have discovered and see which ones preserve multiplication
That should be it
explicity check the preservation ?
for group homomorphism, i used the fact if phi(1) = a, then phi(x)=ax
then rule out the possible values of a using lagrage's theorem and homomorphism order division property
The possibilities are a=0,15,10,25,5,20
So to preserve multiplication you need axy = a^2xy for all x, y in Z12
For x = y = 1 you get a^2 = a, so a should be idempotent in Z30
a is fixed for me
Right
is it, $\varphi(a \cdot y) = \varphi( 1a \cdot y)$
Dubs
What I wrote there is $f(xy) = f(x)f(y)$ simplified given $f(x) = ax$
A Lonely Bean
Anyway the only values of a that satisfy a^2 = a are 0, 10, 15, 25
is it x or cdot?
x
i didn't get this sorry
The homomorphisms determined by these values of a should be these
axy=a^2xy
If $f(x) = ax$, then how would you simplify $f(xy)$ and $f(x)f(y)$?
A Lonely Bean
f(xy)=f(x).f(y)=axay
And f(xy) = axy, right?
Right
a = a^2 is yielded when we let x = y = 1 in that equation
Find which values 0, 5, 10, 15, 20, 25 satisfy a^2 = a
but just verifying for x=y=1 will imply for any x,y?
Well yes because any other x or y will be a sum of 1's anyway
it works since its integers right?
in integers multiplication can be seen as repeated addition
but i don't think this is the case in arbitary rings, arbitary rings addition and mulitplication are fundementally different i suppose
Yes, axy = a(1 + ... + 1) = a + ... + a = a^2 + ... + a^2 = a^2(1 + ... + 1) = a^2xy
Of course
= a + ... + a = a^2 + ... + a^2
can you explain this?
how did it become a^2+ a^2 + ... +
as a=a^2 ?
i see
makes sense
helpful
Yes, given that
how is this all related to the number of homomorphism is the gcd of two groups?
a hint maybe helpful than giving out answer :)
Is it though? We found 4 homomorphisms whereas gcd(12, 30) is 6
Ah are you talking about the group homomorphisms?
In general, when the domain of a homomorphism is cyclic, you can determine it by just the image of the generator
between Zm and Zn, the choices of a are really the common divisors of m, n
So given a homomorphism phi: Zn -> Zm, you need to just find all values of phi(1) such that the order of phi(1) in Zm divides n
Do you know how order of an element in Zm in found?
the smallest the additive powers of a can go is the gcd (a,m)
so it reaches identity in m/(a,m)
i think this is a homomorphism property
The order of the image divides the original order, yes
ie if a is mapped to phi(b), then order phi(b) divides |a|
in the previous example
the possible orders are 1,2,3, or 6
Z12 to Z30, by lagrange a must divide 30 and by image of homomorphism property a must 12
ie a is a common divisor 12 and 30
Right
now to collect a,
i need to manually look for elements in Z12 whose gcd are these
0
15 has order 2
i don't think any other number in Z12 can have order 2
how do i find the number of elements in Z12 having a specific order?
just take phi(order) ?
i don't recall
similarly i found others, but i don't know how this all connected to number of homomorophism being the gcd
@river minnow number of elements of order d in a cyclic group is phi(d) right?
where phi is totient function
the possible orders are 1,2,3, or 6
so number of homorophism are phi(1)+phi(2)+.._phi(6)
idk lol
im trying
this worked tho
it's 1+1+2+2=6
not sure why its gcd
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this is the graph of which function ?
can answer in terms of x and y
,w plot -1/x
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hello im studying for a test and how do i get the outside numbers for example on 30 degrees its radical 3/2 and 1/2 how do i get that?
There are only two triangles you have to remember
This is one of them
The base has length a/2
So $(a/2)^2 + h^2 = a^2 \implies a^2/4 + h^2 = a^2 \implies h = \frac{\sqrt{3}}{2} a$
im still lost
south
Lost on which part?
can you like use a calculator to find it?
Well yeah but that'd be missing the point a bit
If the point is to know these without a calculator
So if we take cos 60 for example, cos 60 = adjacent/hypotenuse = $\frac{a/2}{a} =\frac{1}{2}$
south
and similarly sin 60 = $\frac{\sqrt{3}a/2}{a} = \frac{3}{2}$
south
a is adj right
a is the side length of the equilateral triangle
oh
So what we did was divide it into two smaller triangles
where did you get the 3a/2 from
wait so every time like the denominator is 2 for both
bc for all of them is /2 on each for everything
No, so the base is a/2, the hypotenuse is a
And the height is h (for now)
i get that but how do i get these now without a calc
Ah so with the equilateral triangle cut in half you can get pi/3 and pi/6
For pi/4 you need a different triangle
45 45 90
Yep
Actually you can just let the bases be 1 cause it's only the ratios that matter
So if you have the base being 5 and the hypotenuse being 5 sqrt(2)
cos 45 is 1/sqrt(2), which is the same as 5/(5 sqrt2)
So it might be easier to think of the 30-60-90 triangle as being 1, sqrt(3), 2
The hypotenuse is still twice the base
hm ok
wait so all those numbers are always the same right
i can just memorize the first quadrant then just copy
have you learnt circular trigonometry
man if you havent learnt circle trig
nah i get it tho
then thats all u need for the test
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what is the connection between field extension and the degree of the minimal polynom? for example [L:K]=17 , what do i know about the degree of the minimal polynom?
its 17
because if alpha generates L, then 1,alpha,alpha^2,...,alpha^16 are linearly independent (otherwise it wouldnt generate L and instead a subfield (which could actually only be K itself because 17 is prime)) and then alpha^17 is linearly dependent on the previous ones, so you can write down a polynomial of degree 17 which has alpha as a root
does it make a difference if the degree is non prime?
then there could be fields between L and K
if there is a field K<=F<=L, then [L:K]=[L:F]*[F:K]
but the degree of the polynomial is still only 16 as an example, if [L:K]=16?
well the polynomial is the wrong way to say it
unless you are talking about a specific element already
there could be several elements which generate L
and each of them will have a minimal poly of degree 16
but these minimal polynomials can be different
gtg
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Why only there are two legs the are equal and not all of them?
Do all the sides look equal?
nope
Then there is your answer
nope
You can use congruency testing
the question in why they are only two legs that are equal and not 4
its a class question
So the first step would be to determine what sides you are referring?
the AB and DC
diagonals
all diagonals are not equal
so the class assignment is to tell why there only two diagonals that are equal and not all off them
@hardy vector
what is the sine rule?
Forget it
we didn't learn in class the sine rule
Basically since the side AD is smaller than BC we end up with diagonal not being equal.
right
Let E be the intersection point of the diagonals

