#help-36
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☁️
this is probably an indication I should get more sleep
but let me try again one sec
💤
Okay
actually SWR
we did prove something similar
but it wasn't this
we proved for functions from Rn->R
not from R->R
n=1
the differentiability definition is different though
for R1
to any larger dimension
Is it?
yes
we have f(a+h)=f(a)+<c,h>+E(h) compared to
f(a+h)=f(a)+mh+E(h)
gradient
versus constant
How certain are you something is false here? It seems to me we have established that the limit of f approaches the same value from left and the right of 0, as we have defined E(h) that way
I'm not certain there is anything false, I just feel like I remember the professor doing this proof in two parts, one for h->0- and one for h->0+ and I couldn't understand why that was necessary
It’s necessary most of the time, because we need to prove that the limit even exists for x ⇒ 0. But here we have already established that, so we don’t need to do it in two parts, at least not to my (admittedly very limited) knowledge
To my knowledge the limit only exists for x ⇒ 0 if the limit is the same for x ⇒ 0+ and x ⇒ 0-
But it’s very much possible that I’m wrong, so don’t take this at face value
Maybe someone else can (hopefully) confirm
this is true
yah I feel like it is a nuanced issue here if there is one
@hybrid heath I think I
I've gathered my thoughts here
I have a different proof
presumably with no issue
Since f is differentiable at a,
$$f(a+h)=f(a)+mh+E(h)$$
$$\lim_{h\to 0} \frac{f(a+h)-f(a)-mh}{h}+\frac{E(h)}{h}=0$$
$$\implies \lim_{h\to 0} \frac{f(a+h)-f(a)-mh}{h}=0$$
$$\implies |f(a+h)-f(a)-mh| \to 0$$
And, since,
$$|f(a+h)-f(a)|=|f(a+h)-f(a)+mh-mh|\leq |f(a+h)-f(a)-mh|+|mh|$$
By the triangle inequality,
Since both of the terms on the left go to 0 as h to 0, then
$$|f(a+h)-f(a)|$$
also goes to 0 as h to 0 which implies that $f$ is continuous at $a$
Austin
this should be better
latex cut off a small part at the triangle inequality line. should be an additional +|mh|
but as h->0 so does that
May I ask what m is?
f'(a)!
factorial?
it is a suprisingly more convienent definition of the derivative that generalizes better to higher dimensions, while still being equivalent to your usual difference quotient definiton
in a small neighboorhood of f(a) (being f(a+h) for h->0) f can be approximated by a linear function: f(a)+mh, and an error term E(h) which dies off more quickly than h does as h to 0
so like essentially this tells us we can make a tangent line
with slope m
and you can rearrange this definition to get the difference quotient definiiton
HI Bungo!
why do you need to divide by h on line 2, why not argue directly from the first equation
we need to use the limit fact
just use the general fact that if E(h)/h goes to zero, then E(h) goes to zero
as h->0
so f(a+h) = f(a) + mh + E(h)
right hand side goes to f(a) as h->0
therefore the limit of the left hand side exists and equals f(a)
sure, but you detour into "divide by h" land and then have to multiply by h later, what's the point
Bungo
rhs goes to zero, hence so does the left
btw (just scrolled back a bit) i see nothing here that would call for having to argue with one-sided limits
unless f only has one-sided derivatives for some reason
Maybe I am remembering a different proof then where he made that remark
Seems like I've constructed like 4 different proofs of differentiability => continuity at this point
oh well can't hurt
like SWR said, if you already have a proof for R^n then it should apply for n=1 as well
but no harm doing n=1 directly
yea
brain fart
n=1 is hard
not too bad once I got everything organized now
Is it possible to reason that f can only be differentiable at x if for any h>0 there is a value for f(x+i) for some i<h, which is pretty much the definition of continuity?
I don't think so
Nvm I think I mixed up the definition of continuity
yeah
It’s too late lol
and a singular point can be differentiable
Yeah it’s 2 am and it’s noticeable lol
I think an example of this is like ( I might be wrong) but f(x,y) = 1 if xy=0 and =0 elsewhere
then the partials along x and y to (0,0) both exist and are continuous
so f(x,y) is differentiable at (0,0)
that's not differentiable
This is too advanced for me lol
no, if it were, then its directional derivative at (0,0) would be 0 in every direction
since directionals are a linear combination of the partials
oh right the partials have to be continuous in a neighboorhood of (0,0)
not just along a line
that is not a ball
yea
there's probably some kind of example though
it's not hard to construct examples in R^1
take sin(1/x) times appropriate powers of x, typically
oh wait that does the opposite of what you're saying
differentiable everywhere except 0
if you want differentiable only at zero try multiplying the characteristic function of the rationals by appropriate powers of x
yes I've done a problem like this before
The completed proof
Checks out?
yea looks fine
ty bungo and SWR and others
I was wondering if someone could check my work on this.
By the MVT, for all a,b in R, there exists a c in R s.t
f(a)-f(b)=f'(c)(a-b)
and since f'(c)<=|f'(c)|<=C
f(a)-f(b)<=C(a-b)
so f is lipschitz continuous
which implies f is uniform continuous
qed
all correct except it should be |f(a)-f(b)| <= C|a-b|
where did the abs value bars come from
it's more like, how did you get C into that inequality without using abs values
and anyway, to prove uniform continuity you need to bound |f(a)-f(b)|, not f(a)-f(b) since the latter can potentially be large negative
yeah the statement for lipschitz continuity involves absvals
so they should be here
but MVT does not give us them
so I'm wondering how we pick them up
ah
Bungo I am not sure if I told you this yet
but that hellish problem from my midterm
no one got any credit for it, he kept the scores, and then assigned it to our HW for this week
😭
harsh
you don't get to simply accept defeat and lose points on the midterm, you have to actually solve it haha
should be |f'(c)| <= C
btw, do you need that last line where you divided by |a-b|? what's your definition of lipschitz continuity
but then you create the annoying "uh except when a=b" case, why do that if you don't have to?
natural follow-up question, does there exist a function that is differentiable everywhere and lipschitz continuous, but which does not have a bounded derivative
i.e. is that a necessary and sufficient condition when the function is differentiable everywhere
No
It is an if and only if statement
Lipschitz if and only if bounded derivative
I’ve proven that
yea
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why is $ln(\prod_{i=0}^N e^{x_i}) = e^{\sum_{i=0}^N x_i}$
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Michelle is an experienced target shooter who has scored a perfect bullseye on a target 300m away. If the target was set at her eye level and the bullet left the rifle at a speed of 600ms, how high above the bullseye was she actually aiming her rifle?
the hint is to use the trig identity sinθcosθ = 1/2 x sin2θ
obviously the initial horizontal and vertical velocities are 600cosθ and 600sinθ respectively but im not too sure what to do
says eye level
yeah the projectile will travel in parabola
Oh wait I'm dumb I read that as "she was aiming at eye level"
the missing piece is that the rifle is also eye level
like she's not firing from hip
Yeah I get it now, at first I figured she was on a hill or something
yeah well that is assumed, i dont really see people shooting rifles at hip level
you need the angle
correct
then tg or ctg gives you the height
so u got two equations, one for vertical and one for horizontal displacement.
The unknowns of that system will be time and the angle (although you don't actually need the angle itself)
so u can solve it
yeah but im doing something wrong
oh mind showing work then
aight
i had to iterate that t in, v=u+at was half of the total time so i had to double it, so that's why i crossed out my original answer
sin^-1(9.8/2) is not possible
so idk what ive done wrong
i don't get what the hint is supposed to do
so i can get sin and cos into just sin
if i have sin and cos, i just do 300(sinθ/cosθ)
1200*600/300 = 1200*2 not (1200/300)*(600/300)
ah k, but does that solve everything?
Then 2400 sin(theta)cos(theta) = 9.8 simplifies to 1200sin(2theta) = 9.8, etc.
hmm i see ill try it
I don't think you have that though? Cus you have t = 1200 sin(theta)/9.8 and t = 300 sec(theta), so dividing the two gives you sin(theta) cos(theta) rather than tan(theta)
i got 0.23 as the angle
surely the angle isnt that small
could be
Next u do 300tan(theta)
and that's yer answer
Looked it up just in case and 1.5 inches for 100 yards is p normal https://tpwd.texas.gov/education/hunter-education/online-course/shooting-skills/sighting-in
1.87 is with 300tan
Wait how'd u get 0.23 radians, I got 0.00408. Or did u convert to degrees?
degrees
OK bet
But still I get 1.225 for final answer https://www.wolframalpha.com/input?i=300tan(Arcsin(9.8%2F1200)%2F2)
Maybe u rounded off too much?
Actually rounding off would only make it smaller 
300tan(Arcsin(9.8/1200)/2) where'd u get this?
.
I did see I miss wrote 1200sin(theta) later tho
Wait nvm I didnt
hold up, are u saying 1.225 is how high she was aiming?
yeah i got 1.224 using 4 decimal places
idk maybe I misinterpreted the website, or maybe the problem just used wack values lol
i got the same values
Yeah
a meter seems justafiable right?
Yeah I think so
I just dunno anything about shooting 
but targets are like at least a meter big
So it seems within range
300m away is pretty far so 1m above the target when the bullet will take like 0.5s to travel seems fair enough to me
tbh i dont think i will even get a question similar to this in a test
aight
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L1: x-y=7, L2: 7x+y=1 the acute angle bisector formula will be?
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How would I solve this? I have no clue where to start.
i would start by combining the three ratio statements
you know that the candidate 1 got 4 votes for every vote candidate 2 got
this means that if candidate 1 got 100 votes, candidate 2 got 25 votes
so our ratio of votes is 100 : 25, candidate 1 to candidate 2
we can add in the ratio for candidate three as well, since we know that every 100 votes candidate 1 got, candidate 3 got 13
so the ratio 100 : 25 : 13 would be candidate 1 to candidate 2 to candidate 3
does that help as a starting point? @fresh hedge
Let me try that, one second.
Yeah, it's a good starting point.
What would I do after that? My brain isn't braining right now.
using that ratio, you can find the proportion of people that voted for candidate 1
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when doing multivariate limits
is it vital to identify continuity at a point to evaluate a limit at point BEFORE using the substituion method
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let n be a positive integer. Call a nonempty subset S of {1, 2, . . . , n} good if the
arithmetic mean of the elements of S is also an integer. Further let tn denote the number of good
subsets of {1, 2, . . . , n}. Prove that tn and n are both odd or both even.
i came across this question and didnt know how to prove can someone help
!status
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@hoary prism Has your question been resolved?
I don't know where to begin.
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Let S, T, U be sets, with S ⊆ U and T ⊆ U. Prove that S \ T = S ∩ T^c
I need some help with how to work this problem and turn S\T into something with the compliment of T
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is the derivative correct
looks right
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why is my reasoning wrong
Are you familiar with the product rule?
yes, but in this case, why do we not start with chain rule'
Well what you've done is hardly chain rule.
You differentiated the two functions separately, that's not chain rule.
Chain rule is typically used in compositions.
Something like this:
you must differentate together for it to be chain rule?
what about like nested chain rules or so
d/dx(f(g(x)) = f'(g(x)) * g'(x)
This is what the chain rule is.
In the question you have f(x) * g(x)
Yes, but together for a composite function.
Not for product of two functions.
For that there's product rule.
?
like
i differentiated the first term and applied the chain rule for the second term,
Again, that isn't how chain rule works.
This is a product of two functions.
Chain rule isn't used that way.
If you had something like $\sqrt{x^2+1}$ you'd use chain rule, yes.
Because this is not a product of two functions as you can see.
! What the hell am I doing here?
This is composition.
! What the hell am I doing here?
But in your example there's a product involved.
well could i not treat the term x^4, with other function?
like so
Well you only differentiated the second expression here.
Did nothing to x^4
Which isn't constant wither
So you're wrong I'm afraid.
Do you or do you not know what composite functions mean?
I think that's where we should work.
like i know what you are trying to tell me to do but i dont see why the other wasy would not work. you are insisting I do it like so yes?
Yes, there's a reason for that which I've been meaning to tell you, if only you told me whether or not you knew what composite functions mean...
i apologize
Well do you know?
composite functions as such
f(g(x))
or chain rule
f'(g(x)) * g'(x)
Good.
Now your original query was why exactly can't you use chain rule here, is that right?
uhhhhhhhhhhhhhh
?
the x^4 is outter function and (x +1) was inner function. thats how i saw it
If the outer function were x^4 and inner were x+1
The composition would be (x+1)^4
This is product, not composition.
Let's look at another example
sin(x) and x^4
Outer and inner respectively
The composition would be sin(x^4)
For this you'd use chain rule.
But!
For something like sin(x) * x^4
You'd use product rule.
They're two different scenarios.
and what if you had sin^4 * x
I'm sorry, do you mean $\sin^4(x)$
! What the hell am I doing here?
yes
Chain rule.
It's like this: sin^4(x) = y = z^4, say.
sin(x) = z.
dy/dx = dy/dz * dz/dx
dy/dz would be 4z^3. dz/dx is cos(x). Then you'd sub z back in its place, which would make it look like: 4sin^3(x) cos(x)
Ultimately.
However the point is, you'd need to be able to say when it's a composition and when it's a product.
Do you think you get that yet, or...?
these terms are weirddd
Well, how about I give you a few examples and you tell me which one you'd use.
YES
! What the hell am I doing here?
,texconfigcolor white
You have switched to the white colourscheme.
Well?
first one chain rule
second one product rule
coposition = chain rule
Composition*
multipliing 2 terms = product
! What the hell am I doing here?
It's still chain rule. It seems you still don't have an understanding of compositions.
Well I recommend watching a few videos then, maybe?
Chain rule and product rule of course. Their examples and the way you'll see them being solved, will perhaps make you understand better 'visually'.
However for one last time I'll say:
When it's f(g(x)) it's chain rule. When it's f(x)*g(x) it's product rule.
?
! What the hell am I doing here?
would that be quotient rule
Well, I wasn't asking which rule you'd use here, it's the answer to the previous one.
But yes for this one it'd be quotient rule.
i seeeeeeee
um also, how did we get this, becasue i was thinking just 1/x so we put 1 over the inner function
The derivative of ln(x) is 1/x
But we also have an inner function here.
Which is 1+e^x
ohhhhhhhhhh
The derivative of 1+e^x is e^x
like multiply by g'
Exactly.
ok
um
going back to what we had at the beginning.
im not sure this gives me an answer
This is the right answer.
i dont see it
i
like
multiply the right fraction by the lefts denominator over itself?
i got stuck
You've made an error
You added the second term pre and post multiplication.
Not the first and second term.
It's the same term of two different steps twice.
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Is c correct
bro are u sure
I wanted to ask someone else just incase
is there any reason you should think its wrong
here lemme try
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do i use the integral test for for convergance here?
basically just set up integral from the boundaries, solve then do the limit?
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hello, i'm currently trying to find remainder of 2m^4 - 3m^2 + 1 using synthetic division with -2 as a
ill show my work in a bit, my answer was 45 although i don't think this is correct as remainder theorem gave me 21 as remainder
i just did it and i got 21 using synthetic division
did you forget to add the 0s
because there is a hidden m^3 term and m term
the coefficients of those are 0
so it should be set up as
oh!!! -3
yea sorry it was a typo
np
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u too
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2. I have begun but got stuck midway.
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2
what have you tried?
we would need more context to answer this question
I didnt know what to do so i looked up the answer on symbolab and im going by step by step
do you know integration by parts?
I could do it for some problems
integral xsinxdx
integral 2xe^xdx
is what ive done so far
$\int\arctan(7x),\dd x=\int1\cdot\arctan(7x),\dd x$
light
oh ok that helps
cool! let me know if you can figure it out from there
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Can you help me understand how there are 'k' (1/2) s?
the first 1/2 corresponds the the summation of 1/2
the next one corresponds to the summation of 1/4 = 1/2^2
then the same for the summation of 1/8 = 1/2^3
goes all the way until the summation of 1/2^k
so if you count the summations, we did k of them
one for every inverse of a power of 2
yes
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what is the degree of F?
x -2 -1 0 1 2 3 4
f(x) 5 -2 -3 -4 -11 -30 - 67
you're supposed to find the polynomial f of smallest degree that verifies this?
@brazen sigil Has your question been resolved?
i think so
its just telling me to find the degree of f from the polynomial function
A trick to this is to recursively compute the differences between adjacent outputs
(because all the adjacent x values have the same difference, 1)
So here you have:
- outputs: 5, -2, -3, -4, -11, -30, -67
- 1st differences: 7, 1, 1, 7, 19, 37
- 2nd differences: 6, 0, -6, -12, -18
- 3rd differences: 6, 6, 6, 6
- 4th differences: 0, 0, 0
so is the degree 6?
i thought maybe because of how often it repeats
That has nothing to do with the degree
Take a simpler example: y = 3x+2
Obviously the degree is 1, but let's take some values and try the differences
So at x=0, 1, 2, 3, y = 2, 5, 8, 11
1st differences: 3, 3, 3
2nd differences: 0, 0
Basically if the nth differences are constant, it's a hint that the degree is n
is my degree 3?
Possibly
🤔
This is just a hint, not a proof
I don't think you can prove that the minimal degree is 3 without just finding the polynomial
how do i know for sure?
You have 7 pairs of input and outputs (x and y), so you can make 7 equations based on the expected form of the polynomial
Plenty to find a solution
ok
(x-2)(x+2)(x-3)
i think those are my factors but
i jsut wanna double check
I don't understand, is this another question?
Hm yes (x-2)(x+2)(x-3) is a factor of that polynomial
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<@&286206848099549185>
<@&268886789983436800>
I still don't get it
we're multiplying the row by 2 and switching rows so why isn't it -2
did you find A?
I can send you a picture of my work solving this problem, if you'd like?
yes please
@reef canyon Has your question been resolved?
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how do i do the table in this picture for my question
<@&286206848099549185>
@glass mica Has your question been resolved?
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Where did I go wrong?
you are dealing with cos(2theta), not sin(2theta)
@stuck juniper Has your question been resolved?
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how do i do this?
I would split it into a rectangle and triangle
can you go step by step
nma dougie is acoustic
oi mods ban him
!noping
Please do not ping individual helpers unprompted.
w annghost
AnnGhost!!!
can i get help here
W Annghost
what is the confusion here?
shut up icecold
I gave the first step
wait
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is it correct that {(0,1),(1,0)} is a spanning set for {(0,1)}?
or must spanning set have the same dimension?
what you have listed is a basis for R2
not sure what you mean by {(0, 1)} here
oops
i meant to ask whether R^2 would be considered a spanning set for span((0,1))
no
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where C is the centralizer subgroup
i am so sorry. ive searched out help on this problem like 5 times today and i feel like I have little to no idea what is going on
I think I have shown gC(a)g^-1 is a subset of C(gag^-1), but i am utterly lost on how to show that C(gag^-1) is a subset of gC(a)g^-1
my prof didnt tell us about the centralizer subgroup, and the textbook has like a single sentence definition with no examples and im just so thoroughly confused
Okay, you know the definition of centralizer, right?
not intimately
there is a single line definition in the textbook and im not sure i fully understand it
unless you mean stabilizer?
Okay, what is the one line definition then?
it says: the stabilizer subgroups of each of the x_i's (the representatives from each of the nontrivial conjugacy classes of G), C(x_i)={g \in G : gx_i=x_ig} are called the centralizer subgroups of the x_i's
Yes, so in other words, can you say that $C(a)={g\in G|\ gag^{-1}=a}$?
Tardis
Yes
okay
So can you say that $C(gag^{-1})={h\in G|\ hgag^{-1}h^{-1}=gag^{-1}}$?
Tardis
sure that makes sense
Okay, so if h is any element of C(gag^{-1}), how do you get a on the RHS of that equality?
wait so is h being an element of C(gag^{-1}) a different h in the line from above where it just says h is an element of G? or are they somehow the same?
oh of course right, apologies
do you mean how do you get a alone on the RHS of the equality $hgag^{-1}h^{-1}=gag^{-1}$?
goobybalooby
Yes
just $g^{-1}hgag^{-1}h^{-1}g=a$ ?
goobybalooby
its not $hgag^{-1}h^{-1}$ is it?
goobybalooby
Tardis
You can easily see that $(g^{-1}hg)^{-1}=(g^{-1}h^{-1}g)$
Tardis
yes. so then $g^{-1}hg$ belongs to $C(a)$ ?
goobybalooby
That's correct
is that what we were trying to show?
ohh it is, i think i actually sort of see it
kind of
i mean i see it
So $g(g^{-1}hg)g^{-1}\in gC(a)g^{-1}$, which is essentially $h$
Tardis
oh okay i didnt see it then lol I was just going to say if $g^{-1}hg \in C(a)$ then $h \in gC(a)g^{-1}$
goobybalooby
well i guess those are nearly the same thing
do you think you could look over what i have for the first part? cuz now im worried i did that incorrectly
Alright
That looks correct to me
oh okay. it just seems so different than what we just went over, but if it works it works
thank you so so so so so much
You're welcome
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The supermarket offers jars of jam, bottles of mineral water and packets of salt. A gentleman bought 2 jars of jam, 4 bottles of water and 1 packet of salt, and paid €20. Another gentleman bought 1 jar of jam, 2 bottles of water and returned a packet of salt that was in bad condition, and paid €7. A lady bought 3 bottles of water and returned 2 packets of salt, and paid €2. How much was each jar of jam, each bottle of water and each packet of salt?
take out this system 2x+4y+z=20, x+2y-z=7, 3y-2z=2
and got has a result x=5, y=2, z=2
can it be possible?
yes I think that's right
Plugging in the values work so yes
I was hesitating, since Z and Y are unknowns with different values and I don't know if it could make the same difference.
<@&286206848099549185>
bro 2 people already said you were right, why are you pinging helpers
plug this in to check your answer
i was asking why of this question
two variables being the same doesn't make any difference in solutions of systems of linear equations
ok tysm
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,rotate
where's the question
what's $a_n$ ?
riemann
its a times n
i need to find a and b and n its n
like the substitution for infinite
To clarify, it's
[
\lim_{n\to\infty} \pqty{ \frac{n^2 + n + 1}{2n + 1} - an - b } = 1
]
you have, right?
@tulip coyote
exactly
You may want to think about polynomial dividing that $\frac{n^2 + n + 1}{2n + 1}$ out
@tulip coyote
yeah its infinite
do you want to see the previous exercise? its similar to this one
<@&286206848099549185>
helloooo
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if f(x) = asin(lx) with l <> 0 then it has a period of T = 2π / l
a question here says that the period is T = 2π / abs(l)
which is correct? i always thought it is the first formula but i dont know if period can be negative
@covert hornet Has your question been resolved?
@covert hornet Has your question been resolved?
@covert hornet Has your question been resolved?
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i dont understand
@prisma flower Has your question been resolved?
@prisma flower these are three different types of transformations
are you aware of any types of transformations?
yes
for them the ansswer i got was translation, reflection and rotation
in the order
thats correct
do i have to put any numbers?
yes
how do i do it
i'll go through them one by one
for the first one you need the translation vector
which is basically a way of writing how much the shape has moved
yea'
so for that just pick any point and see how far it moved
so +1?
you need to write how much it has changed in each axis
so if it moves 2 right, 3 up, it would be
(2, 3)
oh
so what do you think this one will be
for the second one>?
for the first one
thats technically correct but not fully
think about it like this
how many points does it move right
and how many points does it move up
for this one theres no up
exactly
so just 0?
yup
so to fully complete the question you would write
"Translation by the vector (1, 0)"
how do i know what number to put first
like when i get 2 numvbers
for future reference if you get one that moves left or down, those would be minus numbers
moving to the right
yeah so the second one is a reflection
so then theres no numbers
do you know which line that is?
no, is it supposed to be referred to as a letter
somewhat
okay so to find the line
try and find the line where the shape on either side is the exact same
its hard to explain in writing lemme get a diagram
ok
yeah
try and find the line that does the same on your diagram
yup
alright
for some reason your questions don't have a scale on their axis so im just going to assume that each box goes up by one
yeah im pretty sure
so now we need a way to mathematically describe that line
yeah
im going to go back to the image i sent you as an example
okay
every point on the line has an x co-ordinate of -2
this means that the line can be described as x = -2
can you try describing the line in your question?
im a little confused
whats confusing you?
ah
in your question, the line is not x = -2
yeah my fault i got confused
im not sure how to describe the line
alright
yup
oh ok
where a is the x co-ordinate of the line
ok i see
for a horizontal line it will be y = a
where a is the y co-ordinate
its basically saying that in this case, x will equal the same no matter what
yeah
so for this case, since the x co-ordinate of the line is 3
we can say the line is x = 3
alright that makes sense
so to complete the question you would say "Reflection in the line x = 3"
yeah
if you get confused on these lines again i recommend using
you can plug in some values and get a graph back
woah ok thanks
trust me this is very useful in maths
i use it decently often
anyways final question
alrgiht ill use it
do u think u could paste it back in theres been a lot of messages lol
cool okay so the last one is rotation
yea
degrees?
thats right
is it just 360
close
wait no
a 360 degree turn will return a shape to the same place it originally was in
no
okay
well basically the trick i use for rotation is
i imagine the shape on a piece of paper
(or just actually draw it)
and for every 90 degrees i turn the paper right once
may work for you as well idk
i probably went into more detail than is necessary for these questions but its better to understand it
its ok it helped me understand
im glad 🙂
one final note
for 180 degrees both clockwise and anticlockwise are the same so it doesn't really matter
true
but for any other angle of rotation you gotta make sure you put one or the other
alright, thanks so much ❤️
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what does that E like that mean
yeah but what does it mean z in 0,inf
(a-ib)-(a+ib)
-2bi
what does tali che means?
such as
such that*
z- z conjugate is a complex number, idk what means to lie in (0, infy)
you can say, if b<0, the imaginary part of this complex number is positive
why
^
oh
-2bi, where (-2b) is the imaginary component
but for that to be in (0, infy), take b<0
but it doesnt ask of just imaginary
post the full problem ?
@full halo Has your question been resolved?
<@&286206848099549185>
@full halo Has your question been resolved?
@full halo Has your question been resolved?
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how to integrate this
Help pls
Please show the original problem, exactly as it was stated to you, with the entire original context. A picture or screenshot is best. If the original problem is not in English, then post it anyway! The additional context might still be helpful. Do your best to provide a translation.
what is a?
@old iris Has your question been resolved?
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multiplying top and bottom by sec^4x seems to work
then u sub
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my first pic is me plugging in my points into point-slope form after i found my slope of the tan line, 2nd pic is the question and 3rd is me double checking that hte derivative i got was correct
@crimson cobalt Has your question been resolved?
.close
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Can someone please explain to me how we solved this
which equality do you not understand
because it’s literally just plug it in then expand and expand and simplify and then lhopital
it’s a comparison test, you compare to whatever you want to compare against
question asks you to compare against 1/n^3 so you just slap 1/n^3 in there
No the question doesn't mention it
oh, to get there you just simplify the fraction
do you know the expression for a factorial
5! = 5x4x3x2x1?
you mean denominator?
Sorry?
the image you sent had black bands on the top and bottom
the complaint is that you took a vertical screenshot of a landscape image so you have like 85% blank space
which were bigger than the image itself
Oh Okay sorry
expand both factorials
so I just plug numbers of the series?
I don't know how to expand it

