Hiiii so I had a question about fourier analysis stuff when studying discrete fourier transforms and fft's
#help-41
golden holly
golden holly
So I was studying DFT today and they an approach like this and so I was wondering why we don't do a similar approach for continuous signals...
Okay so can we just use fourier series on a decaying signal and then periodically extend that signal, take the fourier series of that signal, then just piecewise it so that we only take the part from a to b that the signal is significant over?
I've studied fourier analysis with continuous signals and am familiar with the fourier transform as well
Just wondering why I've never seen an approach like this before
pallid canopy
the fourier transform is defined as an integral on the real line while the fourier coefficients are defined to be an integral on an interval. what exactly are you asking?
amber waspBOT
@golden holly Has your question been resolved?
golden holly
the fourier transform is defined as an integral on the real line while the fouri...
I'm not asking about the definition of a fourier transform. I know what they are.
I'm asking in the context of signal processing. Fourier transform very roughly is a way of applying fourier series to nonperiodic functions and expanding them in terms of complex exponentials
In DFT (discrete fourier transform), we do a similar approach to the one I mentioned if you read my original post, for periodic and non-periodic finite, causal signals
I'm wondering if we can approximate a continuous finite function using a fourier series in an approach like that
pallid canopy
you're confusing the purposes of the fourier series and fourier transforms. just because they have the name "fourier" in it, doesn't mean they both should do the same thing
pallid canopy
i didn't say you didn't understand their formulas
i said you're confusing their purposes
pallid canopy
that they should be compared to each other at all
or at least to the extent you're trying to
fourier series can already give approximations to continuous finite functions
fourier transforms produces a completely new function
pallid canopy
there is deeper connection with regards to hilbert spaces of square summable sequences and square integrable functions, but that requires more machinery
and has nothing to do with applications like signal processing
golden holly
So I was studying DFT today and they an approach like this and so I was wonderin...
So was my original approach with approximating continous finite functions valid then using fourier series?
golden holly
fourier transforms produces a completely new function
I understand this. In a certain kind of limit the texts compares it to fourier coefficients.
A lot of signal processing texts arrive at the fourier transform by taking the fourier series, periodically extending a non-periodic function, then taking the limit of the period approaching infinity
That was the basis of my comparison
pallid canopy
yea that's hand-waving and fine if you don't care about rigor
just tells a nice story
golden holly
Hmm I see thanks for the help
pallid canopy
So was my original approach with approximating continous finite functions valid ...
what are you actually trying to solve
estimate continuous functions with finite support or something else?
or are you supposed to actually find the fourier transform of it
golden holly
there is deeper connection with regards to hilbert spaces of square summable seq...
Also I've seen this a bit when studying quantum mechanics. Found it intriguing that the position space wavefunction and the momentum space wavefunction were fourier transforms of each other
golden holly
estimate continuous functions with finite support or something else?
Not really trying to solve a particular problem, more a curiosity of mine
pallid canopy
yea once again, the math doesn't care about the application
distance, momentum, frequency, time, it does not matter
golden holly
Pretty cool thanks again for the help 🙂
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compact wagon
amber waspBOT
honest dagger
mistake here
compact wagon
is it 16u^1/2 not 4u^1/2??
honest dagger
is it 16u^1/2 not 4u^1/2??
that's one of the mistakes, yes
compact wagon
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languid thorn
i dont know how to do the coordinates for problem 2a
amber waspBOT
i dont know how to do the coordinates for problem 2a
fluid belfry
lets start with the asymptote, because you were very close.
languid thorn
yeah.. i dont know how i got that wrong i figured it out after that its 3
also fixed that the domain is negative inf to 3
fluid belfry
when you are trying to find asymptotes, you have to find when the function is undefined (this isnt a general case, but it is for logarithms)
if you plug in x=-3 you will get -2ln(6)-2, which is defined
fluid belfry
all good, ive definitely made mistakes like that in the past
and i think most of the mistakes stem from that minor sign error
languid thorn
ya def when i look back on it
quick ridge
just 3-x > 0 -> 3 > x -> x < 3
languid thorn
yep yep thats what i did when i redid it
fluid belfry
the domain is pretty easy to solve for once you know the asymptote
languid thorn
i dont know how to do the cords tho like now i understand the domain and asymptote but i still dont get the cords
fluid belfry
hmmm, i dont really understand what they are asking either
languid thorn
i can explain that but idk how to apply it let me just type what it means
quick ridge
so the parent function is 2^x
is what they’re saying i believe
and then they transformed it
languid thorn
its like we use the image points (0,1) and (1,2) then apply the transformations thats happening to those points
ya
quick ridge
to be log_2 of all that
languid thorn
so like how the x and y points change like horizontal shift of 3 and then idk somrhow i should get two points on the graph
quick ridge
ok so if the parent function contains the point (0,1) we wish to find where this point gets mapped to
languid thorn
ya ya
quick ridge
so we can first think about what does the transformation 2^x -> log_2(x) do to some point (a,b) on 2^x
quick ridge
hint: ||inverse functions||
languid thorn
turns it negative 😔
quick ridge
no
languid thorn
thats all i got
languid thorn
ohhh
quick ridge
the inverse functions interchange the x and y yea
since they’re really a reflection over y = x
languid thorn
waitt that makes so much sense now
languid thorn
okk
quick ridge
can you see how it’s reflected over the line y = x
just imagine flipping either of the curves over the line y = x
languid thorn
ohh ya i see now
quick ridge
it will cover the other curve
languid thorn
after that do i just apply the transformations thats happening
quick ridge
so the point (0,1) on 2^x goes to (1,0) on log_2(x)
then we have some other transformations
languid thorn
ya i think for x then itll be 2?
quick ridge
reflect over y axis, left 3, reflect over x axis, then down 2
languid thorn
wait let me think about this more
i think i messed up like i usually use the x naught thing
nevermind i get it 😸
thsnk u guys very mind opening convo
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amber waspBOT
quick ridge
nevermind i get it 😸
what did you get
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tidal rapids
hey guys, is
Sin theta = o/h and y/r
Part of any of the identities (Quotient reciprocal and phytagorean)
or are they just the definition?
fiery moss
hey guys, is
Sin theta = o/h and y/r
Part of any of the identities (Quotient ...
they're derived from the pythagorean theorem if thats what youre asking
tidal rapids
they're derived from the pythagorean theorem if thats what youre asking
OKII thank you !! yes thats what i was asking
tysmmmm
fiery moss
ofc, np!
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glad pulsar
what is this dude
glad pulsar
<@&286206848099549185>
strange field
<@&286206848099549185>
glad pulsar
tried everything but nothing worked
feels like im approaching the question incorrectly
i made some progress on lhl
strange field
if you notice, the first sigma is a_0 + a_2 + a_4 + ...., and second one is a_1 + a_3 + a_5 + .....
can you somehow get this from the given info?
glad pulsar
ye
glad pulsar
can you somehow get this from the given info?
Like (x+y)^n + (x-y)n gives 2(nc0()+ nc2()....
Smth like this?
strange field
the given sigma, if you expand it
glad pulsar
it's a_0 + a_1x + a_2x² + ......
ye
strange field
think if you can get what we want from this
strange field
if you notice, the first sigma is a_0 + a_2 + a_4 + ...., and second one is a_1 ...
we want these 2
glad pulsar
hmm
glad pulsar
think if you can get what we want from this
we can
strange field
how?
glad pulsar
put x=1
glad pulsar
and also x = -1
o
What about left side of the equation
{(1-x)+x^3}^n
if u put x= 1 u get 1^n expansion which is just 1
strange field
1 for both 1 and -1
glad pulsar
put x= -1 u get 10^n
strange field
1-x+x³, put x=-1, 1-(-1)+(-1)³ = 1
strange field
both are equal
how
strange field
yes but one is all addition and one has alternating +/-
strange field
if you notice, the first sigma is a_0 + a_2 + a_4 + ...., and second one is a_1 ...
and we want these
glad pulsar
add them
strange field
1
strange field
strange field
to make it look complex probably
amber waspBOT
strange field
does it serve any purpose
idk about that but it's not an impedance in solving this question, you can just ignore it
glad pulsar
idk about that but it's not an impedance in solving this question, you can just ...
oh ok
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crimson flame
I am studying the Laplace equation in EM and want to know why the exact 2D Laplace equation is the one in the image, why g seems to be a reciprocal of a distance formula, and why the solution function needs to be close to that of a plane.
amber waspBOT
I am studying the Laplace equation in EM and want to know why the exact 2D Lapla...
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spare galleon
I have a question related to linear algebra.
amber waspBOT
I have a question related to linear algebra.
spare galleon
Given two matrices A and B and their product AB.
If the first and second rows of B are the same then so are that of AB.
devout reef
Put your actual question on your first message.
spare galleon
**If the first and second rows of B are the same then so are that of AB.**
This statement is false and I thought it is correct.
spare galleon
Put your actual question on your first message.
I love you
My interpretation is we can consider each row of B as individual vectors.
Therefore, multiplying B by A is actually operating the transformation encoded in matrix A to these vectors inside matrix B.
I have a correction to be made about my question.
devout reef
Yeah, but the result of multiplication between the vector and A depends on the entire rows of A.
spare galleon
Yeah, but the result of multiplication between the vector and A depends on the e...
The rows of A imply what kind of transformation it is.
devout reef
Not just one rows of A, though.
spare galleon
If two vectors are identical then they should be the same after being transformed by some matrix.
devout reef
Hold on
Since you're calculating AB, the first row of AB depends on the first row of A, but the entirety of B.
I thought you're calculating BA for a sec.
spare galleon
I actually have to make a correction
spare galleon
**If the first and second rows of B are the same then so are that of AB.**
It should be “If the first and third rows of B are the same then so are that of AB.”
So it is the first and the third rows rather than the first and the second rows.
I think my conception that regarding each row of B as vectors in the space is valid.
devout reef
Yeah, no. You would've been right if you were regarding each row of A, or each column of B.
spare galleon
Yeah, no. You would've been right if you were regarding each row of A, or each *...
Why would consider each column of B as vectors to be valid and that of each row to be false.
devout reef
You can look at how multiplication is defined for matrix.
spare galleon
**If the first and second rows of B are the same then so are that of AB.**
I did that and the result of operation shows that this is a false claim.
Yet, I cannot still figure out why my interpretation is false.
devout reef
You can think matrix multiplication AB as the dot product between each rows of A and each columns of B.
Note that it's not "each rows of A and each rows of B"
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split sail
Find lim z-> inf z\left(\ln\left(z+1\right)\right)\ -\ z\left(\ln\left(z\right)\right)
split sail
,, \lim_{z \to \infty} \left[ z \ln(z+1) - z \ln(z) \right]
grizzled pagodaBOT
anjali
thick shale
z(ln(z+1/z))
weak zinc
z(ln(z+1/z))
(wrote this wrong btw)
weak zinc
z(ln(1 + 1/z))*
Rewrite this a bit more 
split sail
I don't know the derivative of ln(f(x)). 😄 LOL
mint nacelle
weak zinc
Rewrite this a bit more <a:nyaTease1:571243416932057089>
(doing this without lopital's is probably considerably easier though!)
amber waspBOT
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weak zinc
I also don't know the derivative of ln(x)
Do you know the value of the limit $\lim_{n\to\infty} \qty(1 + \frac1n)^n$ by any chance?
grizzled pagodaBOT
@weak zinc
inland pulsar
idk but you should prob learn differentiation before doing such questions
weak zinc
Rewrite this a bit more <a:nyaTease1:571243416932057089>
hence my suggestion here
weak zinc
z(ln(1 + 1/z))*
Can you make something like that appear here?
grizzled raptor
Hello, good afternoon, my question is: I have a mapping where each component is contractive, that implies that the mapping is contractive?
grizzled raptor
this is the mapping
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proud gazelle
Should I be using parentheses for arcsin like that?
And am I using the ≈ sign correctly? That's all I need to know
proud gazelle
Feels like I'm using too many ≈
pallid canopy
it's fine
proud gazelle
All right, and what does ⟺ mean?
amber waspBOT
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graceful badger
I saw this in a list of examples:
amber waspBOT
I saw this in a list of examples:
graceful badger
That should be -420, correct?
grizzled pagodaBOT
Result:
420
That's positive, though
pallid canopy
420 is the right number and negative is the right sign
graceful badger
,calc (-1 (7/3)) / 180
grizzled pagodaBOT
Result:
-0.012962962962963
hard jolt
amber waspBOT
hard jolt
I dont get what to do for this question
I know that $$(f^{-1})'(y) = \frac1{f'(x)} = \frac1{f'(f^{-1}(y))}$$
grizzled pagodaBOT
Xotiic
amber waspBOT
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hollow cape
is that literally the entire question or is there more to it
hard jolt
is that literally the entire question or is there more to it
That’s it
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exotic olive
am i right with D here i tested n = 0 and it satisfies one of the points
lusty pine
correct
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worn cosmos
amber waspBOT
true jackal
Well, you should also notice that there's an extra 2 inside sin(2x)
true jackal
Therefore, this should ring you a bell
worn cosmos
i need to work on my trig identities 😭
true jackal
i need to work on my trig identities 😭
Yeah they appear quite often in derivatives (and also integrals)
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sharp dock
How do u do question 1 f)?
amber waspBOT
How do u do question 1 f)?
verbal jewel
!15min
amber waspBOT
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brisk nexus
Hi
naive pivot
I made it where u = tanx
How about u=tan^2(x) might help better
sharp dock
How about u=tan^2(x) might help better
Ok
grizzled pagodaBOT
Tazculator
sharp dock
Wtf is that
brisk nexus
Tazculator!
brisk nexus
...
sharp dock
How do u do question 1 f)?
Help me with this
brisk nexus
It is the complement of the square
grizzled pagodaBOT
Tazculator
brisk nexus
I took the step after this
brisk nexus
sharp dock
3u²-4u+1=0
brisk nexus
Ok
grizzled pagodaBOT
Tazculator
naive pivot
Well you can solve for u in different ways
the way Tazcularor suggested is completing the square
brisk nexus
I wrote that thing above in another way
sharp dock
Well you can solve for u in different ways
the way Tazcularor suggested is comp...
Let's not use taxular pms
Or wtv it's called
naive pivot
Let's not use taxular pms
You simply wanna use the quadratic formula yea ?
brisk nexus
Let's not use taxular pms
Tazculator!
sharp dock
You simply wanna use the quadratic formula yea ?
Ig
This is what I'm doing for this other question
brisk nexus
I would have proceeded like this
grizzled pagodaBOT
Tazculator
grizzled pagodaBOT
Tazculator
sharp dock
Ty for tryna help but idk what ur doing
ruby dome
Hi
sharp dock
Yo
ruby dome
Yo
sharp dock
Help me
brisk nexus
sharp dock
Is this right so far?
What do I do now?
Damn
How
I have a test on this
So pls
Someone tell me
naive pivot
Looks correct but you still need to solve for tanx
sharp dock
Looks correct but you still need to solve for tanx
How 😭
ruby dome
Its clear what tazcalculator said
sharp dock
yea
brisk nexus
@sharp dock Bro Is here !
sharp dock
u=tanx then
-1/3=tan(x)
After that?
naive pivot
yea
yk what values of x that satisfy
tan(x)=-1/3 And also tan(x)=1
(Bcz u also equals 1)
naive pivot
Damn
naive pivot
Then x is -1/3
No
ruby dome
Tan(x)=-1/3 -> x=arctan(-1/3)
ruby dome
Yes
sharp dock
I'll figure the rest out
ruby dome
Where
sharp dock
The final answer should be pi/4, and 5pi/4
ruby dome
,w tan(x)=-1/3
grizzled pagodaBOT
ruby dome
,w tan(x)=1
grizzled pagodaBOT
sharp dock
Using the cast rule
Where tan is -
Right
Is that all?
Tan is negative in the 2nd and 3rd quadrant
ruby dome
Where tan is -
Wdym
ruby dome
When you make the arctangent even the minus I have to put in
ruby dome
It's not 5π/4
ruby dome
π/4 is what you end up with
sharp dock
Huh how
Please how
Can someone please write it on paper for me?
For the love of God
I'm about to lose it
I'm sorry but idk
ruby dome
,w tan(x)=1
grizzled pagodaBOT
grizzled pagodaBOT
sharp dock
Ok ok
BUT HOWOWWW
Man it's alr
Ima figure it out on my own or ask the teacher
This isn't helping
.close
amber waspBOT
ruby dome
What
ruby dome
What is not clear
ruby dome
Okay
ruby dome
Tell me where to start
ruby dome
sin(x)=t
sharp dock
What?
ruby dome
This leads you back to a second degree algebraic equation
sharp dock
I don't wanna know what it leads me to
ruby dome
You solve it and then return to sin(x)
sharp dock
Can you solve it on paper? And show me the final answer
ruby dome
No
ruby dome
Wait
I can't do it now
I got the answer anyway
It was easy
t=-3 , t=1 -> sin(x)=1 -> x=π/2
ruby dome
Yes
ruby dome
Yes
sharp dock
Then we factor it
grizzled pagodaBOT
sharp dock
So t² + 3t - 1t -3 =0?
brisk nexus
Bros are cooking
sharp dock
Yea so 3 × -1 is -3 and 3 + -1 is 2
sharp dock
I think my cell phone will turn off soon
Charge it
Alr anyways thanks for trying to help ig
I'll ask chatgpt
ruby dome
Wait
sharp dock
Okok
ruby dome
Find the solutions and then return to sin(x)
ruby dome
You will get a solution sin(x)=-3 which makes no sense because sin≥-1
ruby dome
Always the same thing
ruby dome
CSC(x)=t
sharp dock
Okok
Ok nvm I got it
Cya
,close
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.open
.close
Alr wtv
Cya
Ty btw
brisk nexus
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Kenzo
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Kenzo
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Kenzo
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dapper trench
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How did you get this equation
shouldn't there only be one dV/dt
verbal lark
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dapper trench
you used ohms law right
verbal lark
shouldn't there only be one dV/dt
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dapper trench
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ok
verbal lark
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dapper trench
how did you get dI/dt as -1/3
verbal lark
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dapper trench
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in the probllem?
verbal lark
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dapper trench
ohhh my bad
verbal lark
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dapper trench
one second ill think abt it
verbal lark
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dapper trench
yeah
verbal lark
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dapper trench
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OH i see
yeah there shouldnt be a V there
just dV/dt
try with 1 and see if it works
verbal lark
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high moon
Martha claims she can roll triples with three dice in fewer than 15 rolls.
What is the expected number of rolls that it would take to roll the first set of triples?
high moon
Why doesnt the geometric formula q/p work
where q is the probability of failure and p is the probability of success
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@high moon Has your question been resolved?
keen pawn
Trying to orthogonally diagonilse this [
\begin{bmatrix}
3 & 1 & 1 \
1 & 3 & -1 \
1 & -1 & 3
\end{bmatrix}
]
grizzled pagodaBOT
A dense set(Ping when reply)
keen pawn
so I start by finding it's eigenvalues
so the eigenvalues of 1 and 4, with 4 having a geometric multiplicity of 2
sterile nymph
So you get 2 for free and you just need to make sure the second eigenvector for 4 is ortho to the first
sterile nymph
Once you have the matrix of eigenvectors you just need to invert it
And you're done
keen pawn
mhm
so I'll now have to solve $\begin{bmatrix} 2&1&1\1&2&-1\1&-1&2 \end{bmatrix}\begin{bmatrix} x\y\z\end{bmatrix}=0$
grizzled pagodaBOT
A dense set(Ping when reply)
sterile nymph
u.v = 0 if and only if u perp v.
keen pawn
yes
sterile nymph
If we consider the first two columns
We have 2 + 2 - 1 = 3
These are not orthogonal
sterile nymph
But you need orthogonal eigenvectors
keen pawn
I'm solving to find eigenvectors
sterile nymph
Am I missing something?
sterile nymph
The diagonal matrix is just the matrix of eigenvalues
keen pawn
$\begin{bmatrix}1&0&0\0&4&0\0&0&4 \end{bmatrix} \end{bmatrix} \begin{bmatrix} x \y \z \end{bmatrix}=0$
grizzled pagodaBOT
A dense set(Ping when reply)
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reaction for more information.
(You may edit your message to recompile.)
sterile nymph
Exactly
keen pawn
\begin{bmatrix}
1 & 0 & 0 \
0 & 4 & 0 \
0 & 0 & 4
\end{bmatrix}
\begin{bmatrix}
x \
y \
z
\end{bmatrix}
= 0
grizzled pagodaBOT
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(You may edit your message to recompile.)
sterile nymph
And for this diagonal matrix, your eigenvector matrix will have in its first column the eigenvector for 1.
And the second and third columns the eigenvectors for 4
keen pawn
so what would the spctral decomposition look like?
sterile nymph
P^(-1) D P where P is the eigenvector matrix and D is the eigenvalue matrix
sterile nymph
Ooooh, I see what you did now
Sorry, I thought you were claiming that the matrix with 2s in it was the eigenvector matrix already solved
sterile nymph
It's just the matrix A - I
keen pawn
$\begin{bmatrix} 2&1&1\1&2&-1\1&-1&2 \end{bmatrix}\begin{bmatrix} x\y\z\end{bmatrix}=0$
grizzled pagodaBOT
A dense set(Ping when reply)
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sterile nymph
Yes, ref does work with the augmented matrix
keen pawn
so I'll now have to solve $\begin{bmatrix} 2&1&1\1&2&-1\1&-1&2 \end{bmatrix}\begin{bmatrix} x\y\z\end{bmatrix}=0$
grizzled pagodaBOT
A dense set(Ping when reply)
keen pawn
so I have $\begin{bmatrix} 2&1&1\0&3&-3\1&-1&2 \end{bmatrix}\begin{bmatrix} x\y\z\end{bmatrix}=0$
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A dense set(Ping when reply)
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keen pawn
\begin{bmatrix}
2 & 1 & 1 \
0 & 3 & -3 \
1 & -1 & 2
\end{bmatrix}
\begin{bmatrix}
x \
y \
z
\end{bmatrix}
= 0
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A dense set(Ping when reply)
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keen pawn
$\begin{bmatrix}
0 & -3 & -3\
0 & 3 & -3 \
1 & -1 & 2
\end{bmatrix}
\begin{bmatrix}
x \
y \
z
\end{bmatrix}
= 0$
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A dense set(Ping when reply)
keen pawn
$\begin{bmatrix}
0 & -3 & -3\
0 & 0 & -6 \
1 & -1 & 2
\end{bmatrix}
\begin{bmatrix}
x \
y \
z
\end{bmatrix}
= 0$
grizzled pagodaBOT
A dense set(Ping when reply)
keen pawn
no point in row reducing it further IMO
I already know z=0
so (1,1,-1) is an eigenvector
as 3y+2z=0;6z=0; z-y+2z=0
,w is (1,1-1) an eigenvector of [3,1,1][1,3,-1],[1,-1,3]
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Requested by physicsrocks
sterile nymph
,w eigensystem {{3, 1, 1},{1,3,-1},{1,-1,3}}
grizzled pagodaBOT
sterile nymph
That's an eigenvector for 4 though
sterile nymph
Probably an arithmetic error
grizzled pagodaBOT
A dense set(Ping when reply)
sterile nymph
And you can add the second row to the third
keen pawn
yeah
sterile nymph
To get x - z = 0
keen pawn
so that gives us (-1,1,1) as desired
sterile nymph
So we have -x = y = z yeah
keen pawn
the other two eigenvector can be calculated similarly
sterile nymph
Best of luck!
keen pawn
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near flower
hi how do you do this?
near flower
<@&286206848099549185>
lime verge
u worked anything on this?
near flower
yep
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near flower
the answer was like 110.92 degrees
110.92 degrees and 535s (i got the working out for time right but i got the degrees wrong so i got the time wrong asw)
shrewd palm
110.92 degrees and 535s (i got the working out for time right but i got the degr...
and you are wondering why your degree is different
you probably were supposed to add 90 degrees
near flower
i did that
near flower
this was my working
shrewd palm
oh i see
near flower
like i got close to it but its not the right answer but i also dk whr i went wrong
shrewd palm
walk me through hwo you got 0.5 and 1.4
near flower
good question wait a second
oh this is awkward i sent the working out for the wrong kinematics question
shrewd palm
XD
shrewd palm
the boat problem is the question though right?
near flower
the boat problem is the question though right?
yea
i also had problems with the other one (the one for the working i sent) but ill leave that to another channel
near flower
nope sorry
shrewd palm
ok well thats how you get it
draw a picture, take the sume of x velocities and y velocities
combine them with squareroot(a^2 + b^2)
use inverse tangent to get angle
and then find the distance across the river with that angle
and solve for time
near flower
ok this might seem dumb but i always get confused on calculating the angle, like which angle r u meant to calculate
shrewd palm
yes because of the 0.75 m/s flow of the river
near flower
is it cus the river pushes the boat like outwards
shrewd palm
yeah
near flower
ohhh right so u just always find the angle with respect to whatever they give u basically?
near flower
rightt that makes sense
shrewd palm
ohhh right so u just always find the angle with respect to whatever they give u ...
yeah thats a good general rule, and if you're off by 180 or 90 degrees the teacher will still know it's correct
near flower
alright got it thank you
wait if u dont mind
can u do the other kinematics question asw
near flower
ohh its not tan theta
shrewd palm
No because it’s just combining the x velocities
near flower
yea i just made a silly mistake
shrewd palm
Ah gotcha
near flower
Alright thank you for ur help
shrewd palm
You’re welcome
near flower
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unborn mauve
How do find a subgroup of a group that is the symmetries of a figure?
For example, if my figure is a rectangle (so is a group in S_4),
and is labelled as follows:
1--------4
| |
2--------3
How would I use the rectangle above to find a subgroup of S4
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How do find a subgroup of a group that is the symmetries of a figure?
For exampl...
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zinc arch
How hectoliters in 3 liters in?
amber waspBOT
How hectoliters in 3 liters in?
split sail
100L = 1 hectolitre
Then 1L = 1/100 hectolitre
3L = 3/100 hectolitre = 0.03 hectolitre
zinc arch
Can you show me the table of conversion?
<@&286206848099549185>
split sail
!15mib
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zinc arch
Only 3 min difference
split sail
4 min*
weak fern
zinc arch
No give mike like
Hektoliter, dm, etc milliliter centiliter mililiter
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snow blade
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royal parcel
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royal parcel
Could anyone hint me for this? Im quite stuck
The previous question was to show that $b_n=\frac{a_1+a_2+\cdots+a_n}{n}$ converges to $a$
grizzled pagodaBOT
somethingwrong
royal parcel
oops just realised it should be $b_n=\sqrt[n]{a_1a_2\cdots a_n}$
grizzled pagodaBOT
somethingwrong
quick spoke
consider log(a_n)
royal parcel
The previous question was to show that $b_n=\frac{a_1+a_2+\cdots+a_n}{n}$ conver...
ohh okay i think I see it, i haven't unlocked logarithms yet. but essentially i first show that (a_n) converges to a implies log(a_n) converges to log(a). Then, log(b_n)=(log(b_1)+...+log(b_n))/n which reduces to this previous question
vernal surge
if you don't have logarithms yet, there is an alternative way
do you have am-gm inequalities?
royal parcel
do you have am-gm inequalities?
nope
but could you give me abit more about how I would go about using am-gm inequalities? I can only imagine getting an upper-bound at most
vernal surge
using the harmonic mean too
I think it was something like
$\sqrt[n]{a_1...a_n} \geq \frac{n}{\frac{1}{a_1}+...+\frac{1}{a_n}}$
grizzled pagodaBOT
rbit
vernal surge
now what would be left is to show that the harmonic mean indeed has limit a too
you can start with lim a_n = a and instead, consider
$\lim_{n \to \infty} \frac{1}{a_n} = \frac{1}{a}$
grizzled pagodaBOT
rbit
vernal surge
from here you can derive the harmonic mean
this all requires a_n > 0 though, well the question wouldn't really make much sense otherwise anyway
royal parcel
ohh okay i think I see it, i haven't unlocked logarithms yet. but essentially i ...
ah im still working through the method of taking logs
royal parcel
this all requires a_n > 0 though, well the question wouldn't really make much se...
oh yes i realised that too
thanks for the this method too, I will try it when Im free
vernal surge
using log seems easier, this one is more elementary though
royal parcel
i think i get the gist of it
royal parcel
using log seems easier, this one is more elementary though
the proving of lim ln a_n = ln a is taking me abit but I'm getting there
vernal surge
there is one property that ln has, which makes this trivial pretty much, but if you don't have all that theory yet it will be tricky
royal parcel
continuity?
vernal surge
yeah
royal parcel
right, don't have that yet too unfortunately haha. but thanks again for the help
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sharp dock
How do I do 1b?
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How do I do 1b?
pallid canopy
<@&286206848099549185>
!15m
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pallid canopy
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sharp dock
<@&286206848099549185> how do u do this?
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sharp dock
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pallid canopy
hollow cape
what are you having trouble with
pallid canopy
stick to one chanenl
desert rover
<@&286206848099549185> how do u do this?
treat it like a regular equation but when you multiply or divide across the inequality with a negative number flip it
lusty pine
what isnt this his only channel
desert rover
that’s all
sharp dock
treat it like a regular equation but when you multiply or divide across the ineq...
How?
I'm so lost
sharp dock
I expand it first right?
hollow cape
yep
sharp dock
<@&286206848099549185> how do u do this?
.
Alr nvm this isn't helpful
No one is helping
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split sail
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split sail
would r(t) just be $t \hat i + t^2 \hat j + t \hat k$
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mellow hornet
Yes
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zealous flare
How would I go about solving this?
amber waspBOT
How would I go about solving this?
toxic talon
Hey how would I do the is fixing my throat
low crypt
How would I go about solving this?
what is the height of each trapezoid? (you can see it in the images)
toxic talon
6+384672818+3926572818x48583818495827184958538divided by 138582
zealous flare
11 cm and 33
low crypt
11 cm and 33
how do you find the ratio between 33 and 11?
frank flint
each heigh *3
zealous flare
how do you find the ratio between 33 and 11?
Subtract?
dull pike
low crypt
uh well 33*(1/3) is 11
but in this case the other way around
11*x = 33
(just solve for x)
zealous flare
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harsh quiver
Hello! I am in need of help. I am currently challenging myself and trying to do Trigonometry, but obvioulsy I don't know ANY of the common formulas. As you can see, I already chose an answer. This was guessed however, because I don't know ANYTHING! Please someone help me. The photos of the questions are listed below:
harsh quiver
<@&286206848099549185>
livid gull
ik the calculator trick
livid gull
<@&286206848099549185>
do you want to find it in the calculator?
scarlet trail
Hello! I am in need of help. I am currently challenging myself and trying to do ...
this is funny af
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