#help-28
1 messages · Page 195 of 1
yes
Nah im making is even more confusjng anyways
There cannot be a cube w/ 4 shaded sides.
Because to have 4 shaded sides, it MUST be the cube itself
It cannot be covered
So there can be a maximum of 3 shaded sides.
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I need help. So let's say P= -½ + 2 × |⅓-⅚| and Q= 2,5 × 4,8 : (-1,5).
What is P/Q?
The correct answer is supposed to be -16, but I got -1/16
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idk where to start with this question. Would appreciate some help 🙏
@dusky canopy Has your question been resolved?
try finding a pattern for n=2,3,4
oh yea, forgot to mention. The teacher did say "attempt" to find the general solution to this without finding a pattern
*he said this for the whole assignment overall, not just this one question. So, I assume he doesn't want us to solve it by finding a pattern ._.
yea i don't really see a pattern ngl
plus the expansion even for n = 2 is stupidly long
show it for n=2 and 3
the only reference he gave was this:
which i didn't really figure out how to manipulate it into this form

I ain’t expanding this man -_-
I ain’t seeing a pattern

And ma teacher says this is one of the normal difficulty questions on the mid term exam, I’m like so done for wth
And we’re just three weeks in into year 1 linear algebra 
yea let's just call it here. ima wake up later and try to do this thing again from scratch by looking at his ppt lecture
what a cancer unit 1 introduction to linear algebra
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can someone teach me how to graph in 3d cordiniate system? for calc 3?
<@&286206848099549185> DIRE NEED OF HELP PLZ
on paper, not on geogebra or desmos
Like i can graph (0,0,1)
Or (0,0,6)
are you required to draw a 3d graph on paper in homework or in an exam?
What
isometric paper?
ill give u an exampple
First draw a 3d coordinate system
Nono just regular paper
Like this
See the verticies
I needa be able to point those and connect dots to draw a tetrahedra
you don’t need to be able to plot them, just visualise them, right?
I need to be able to plot them
and draw the tetrahedra
like a rough sketch
Like (0,0,0) = super EZ
(3,0,0) = Ezzz
(0,4,0) = ezz
(0,0,5) = ezz
But sumtimes he be giving sum hard points like (6,5,3)
how would I graph that point?
on a 3d coordinate?
why? does the question explicitly require it
because this one doesn’t
During exams he requires it
this one doesnt require it because its homework
he asks us to use geogebra
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doing either composites or functions and just lost how to find the domain 
Alright have you found the composite function yet
I don't even know what that means 😭 My class started 3 days ago and its been confusing
Like I’ve been trying to do it off of the help video but I’m lost because of the +3 next to the x and idk why the all real numbers on the help is 0
because if I do the times x on everything idk if its still 2/3 -1x or if I combine the 2 and 3?
what r u having difficulty with exactly
a composite function means
Ohh
Then I think I know them? The teacher legit just started teacher about them yesterday
so basically a composite function is f(x^2)
like before inputting x in the function
u first substitute in g(x) and use That output as an inpur for f(x)
can u show the full working
Uhm I might just take a pic of my paper cuz I’m doing this on paper but the assignment is online
what did u do in the 3rd line?
the one that has the 1 on top or the x times by the stuff?
yes
the standard way to simplify it is take x+3 as LCM and make the denominator as one fraction
and then bring it up
but when finding domain u usually should not simplify
take the 2nd line for example
u have just written f(g(x))
thats how it was written in the video and how to put them together so I've been just going it like that
yeah that si correct
now we just have to check the points where f(g(x))
is undefined
take that small 2/x+3
for a function to be defined every single term has to be defined right
ok
so for this to be defined
x+3 not equal to 0
x not equal to -3
we have found one point where x not defined
now for the other point
we have 1/(2/x+3) -1
the denominator of this fraction must be defined right
so we can say
(2/x+3) -1 not equal to 0
= 2 is not equal to x + 3
x is not equal to -1
so domain will be all real numbers except -1 and 3
ok lemme try that
omfg the question online changed
wait i think im slowly getting them tho
its just hard to do it because i suck with word descriptions 😭
ah
ur going in the write direction
klojhds
what u ve written in the second line dont simplify it
u start analysing from there
it still says I've been getting them wrong
oh i see
the domain ir R-{3,-1} not {3,-1}
it gives me a answer key that shows me the right answer but it remakes me do the question with new numbers but it doesnt give the thought process
ohhhh
i see
oh im so sorry
it is -3
i didnt see the question properly
because if x + 3 needs to b 0
x must be -3
ok
mb
so for this one x must equal 4?
4 and u have to find out for which value of x 1/(x-4) + 2 is 0
because the denomintor of the f(x) must also not be 0 right
would I -2?
Finally got it right 😭
this isn't the same thing but idk why this got wrong when they look the same
What's 3x2? 😉
I just realized that thanks 😭
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i need help on all of this
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thx chat, alot of help
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i dont even know where to start
what do you have to do
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so basically they're just integrating the differential of u(x, y) if I understand correctly
so they're integrating wrt x and y
you cannot integrate wrt two variables simultaneously
if you look closely you can notice this is the total differential
partial integration ahh
so you can see u_x and u_y
jk
yeah
i don'
If you integrate one wrt to one variable you got u(x,y) + constant function
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For B
Our teacher want us to compute this with geometric series, anyone know how to start?..
First, find your rate and write the first 3 terms
0,005
Yes
So what would your first term be
I understood the first question, we solve for future value
Oh lmao sorry
Np, its the b question that is mindf me
The investment continues, but every month we draw out a certain amount
yes
So from out last term, imma just call it Tn
We create a new Gp
With Tn as the principle
There will be a certain amount withdrawn each month, so use a pronumeral to represent it
We want to withdraw something a
We assume it’s after it compounds
Geometric progression
Its the uhhh
Hang on a sec
$S_n = a \frac{1 - r^n}{1 - r}$
Sho
Yes
yep
I have solved for A but it’s not correct
ok
Already tested it
in the first question or?
yes
We need our yearly 6% interest rate to be monthly
You used sigma here
But why not use this?
of what?
Of your part B
This -a would be your first term
If I were to solve for A now
we multyple by the denominator
right
to the future value
and then devide by the top to get A alone
I would just put the thing in the calculator but yea sure
its wrong method
Hang on a sec
Oh lmao
Wait
Your rate is still goong
Its not just your tn
Tn
Well now its 15 years not 40 years as in part a
You forgot it still compunds
The 398298 still compounds?
Yea
Yes i know
but the thing is that the
If i were to use the formula u said
Ohhhhhhhhhhh
Like that???
really
then i multyple by the denominator and devide?
although im wondering if it should not be 179 in the right hand side as N
so this should be correct?
If its not, idk what happened
Ok i will check, thanks so much
if i multyple the (1-(6/1200) to the (1+(6/1200))^180
it will be (1+(6/1200)^179
no
Me too I don’t understand a shit
Ill
Do it
Hang on a sec
Ok
I see
I honestly hate this q cause its not specific enough
Part A is weird cause this basically says that you compund before you put 200 in
This is saying it withdraws and then you compound it
Yes i know
its really weird
im starting to wonder if she have done something wrong
The only thing you need to do here is multiply a by 1.005
In part a, she compounds nothing at first and then adds 200 dollars
Doesnt make sense to me but meh
Part b, i thought shed keep it that way
waaaait
the compounding
in the left hand side
should be 179
then it should be right?
Let me write it
This
I disagree with it, but its the answer
Technically this is the correct one
But since you can divide both terms by a, it can be 179
i dont understand man
T1 is the first month
T2 is second month
We keep going until at T180, the balance is 0
yes
I understand that
We will then + over the aR
and then revide everything by R(R^180-1)/R-1
so what i forgot was a 1,005
Cause
I thought it would compound
And then you withdraw
But it withdraws and then compounds
You should ask your teacher to clarify these things so you know which is which
Yea
Just maybe ask your teacher to clarify when it compounds
Then youll be fine
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Can someone explain to me how the “Objective Function” for d was found?
This is a optimization problem
pythagorean theorem
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Thanks
cereal killer
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Working with limits... I'm not entirely sure what to do with some of these symbols
I understand ε to be just "a really small number", per https://www.rapidtables.com/math/symbols/Basic_Math_Symbols.html ...
List of all math symbols and meaning - equality, inequality, parentheses, plus, minus, times, division, power, square root, percent, per mille,...
But for δ it's simply defined as the "delta function" - that's... not helpful.
well it's not the delta function in this instance anyway
basically ε represents a small distance between the output of a function and the limit, and δ represents a small distance between the input of a function and the point it is approaching
... but if the input is a variable...
I mean... x doesn't approach anything, really..
we read [ \lim_{(x,y) \to (0,0)} ] as ``the limit as $(x,y)$ approaches $(0,0)$''
cloud
as long as it is defined in the neighborhood of that point then it's fine
Ok, so...
... what can I actually do with that information?
Like, in the example..
δ is essentially > 0, but < then..... sqrt(ε/5) is essentially 0, so...
basically we want to establish that, if (x,y) is very close to (0,0) (we call that distance δ) then f(x,y) will be very close to 0 (we call that distance ε). we want to show that for any desired output distance ε, we can choose an input distance δ that will make it true
i will note that the ε-δ definition of two-variable limits is a bit more complicated but has a very similar meaning to the ε-δ definition of one-variable limits. so you may want to look into that first
The explanations there are just as devoid of meaning
"Here's a symbol.. we're not going to define it or explain it... moving on."
English is not my instructor's first language, either...
So... where does |f(x,y) - 0| come from? Why are we considering it?
Comes from the first sentence
along any line y = mx, the lim is 0?
So.. why "consider" it, and then in the very next step, drop it out of the equation?
Because y=mx is not sufficient for a proof
Right, because the limit would have to be 0 everywhere
Do you know of a better resource that explains why the chosen steps are taken? My text and my instructor don't explain why things happen in these examples
There's too much I don't understand in the text.. I'd be asking "why this, why that" for hours
just a technique you memorize and repeat elsewhere
or work backwards from epsilon to find what delta has to be in sqrt(x^2 + y^2) < delta
Ok, but if I don't know "why" I'm doing something, that makes it extraordinarily difficult to apply it to an equation that takes a different form
then work backwards
should be easier once you understand the one-dimensional case first
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if i have z= xy and i want to take the partials i would get
dz/dx = y
dz/dy = x
but here x and y becomes constants.
i'm not sure how to use this result. what does it means graphically?
x and y are not constants, we just "treat them as constants" for the purposes of differentiation. so dz/dx is a function of x and y (although it depends only on y)
ok this was my next question indeed. ok thanks, i'll think more about it
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Here is what I'm trying to achieve
Here's my current progross:
Im really close to replicating this effect but my calculations are still off, I'm not sure if this is the type of math I can get help with here but I'm giving it a shot.
My goal is to apply rotation to texture Gui's on each individual face so the green side of the gradient is always facing the dot.
This is done in two ways:
-
Get the direction of the cube relative to the reference point (or the dot in this scenario
-
Get the angle to rotate each face's texture based off their local direction relative to the reference point
-
Calculate how much the face is facing the direction of the reference point within a value of -1 to 1 ("1" meaning the face is facing directly at the point, "0" meaning the face is directly perpendicular, and "-1" where the face is facing the direct opposite direction)
-
Using the face direction calculation, offset of the gradient texture taking the angle the texture is rotating into account.
What's wrong with my calculations?
@slow ermine Has your question been resolved?
@slow ermine Has your question been resolved?
@slow ermine Has your question been resolved?
@slow ermine Has your question been resolved?
@slow ermine Has your question been resolved?
Are you just trying to illuminate the surfaces?
Like the dot is a light source and the faces / portion of faces that face the source are coloured green
No each face has a color gradient, I am basically adjusting the rotation of the gradient and the offset of each face individually relative to the cubes orientation
No but what is the final result you’re trying to achieve?
From here at least, when you say the green side always faces the dot, it should be the same as what I said
Essentially the green parts are illuminated whereas the red isn’t
Sort of, but instead of thinking of it as a light source, think of it as a direction. So basically the threshold is just a line in 3D space. Once the cube reaches this line, any face crossing it will change to red
what software are you using?
i know i'm not helping solving your problem, but the way i would do this would be in a shader, if i had access to the position of each point on the surface, would be to map the gradient onto the distance from surface point to the light.
Maybe if you explained how the coordinate system is setup, someone will be able to help
I'm not entirely familiar with roblox scripting
What's CFrame?
@slow ermine Has your question been resolved?
I was thinking about using trig formulas to measure the side of each face and place a point where gradient gradient line ends, then simply change the offset and the rotation of each adjacent face so the points line up with each other but idk
Something likes this?
What points would you use?
CFrame is just the combination of two vectors in a 3D space. The first tells its position and the 2nd tells its orientation relative to the world axis
the shaded point position on the surface of your object. I'm suggesting to just remap a distance field.
So like, use a plane as the threshold, and use the intersecting points on the edges of each cubes face to map each gradient?
No, in a shader you would just have access to the world position of each point on the surface that is being shaded, means you get the coordinate of the intersection between camera ray and surface.
Once you have that, for every point on screen, calculate the distance from your object and map a gradient on it. This normally is parallelized so you can do this with many many points. It's a computer job.
It works with any object of any polygon count.
What you are trying to do is certainly interesting anyway, but I can't help you there.
Hmm that is interesting, I changed my approach however by intersecting a 2D plane with the cube, and created showing this intersection on the edges exclusively. Here’s what I came up with:
The idea now is for each face with at least 2 points, get the midpoint between them to calculate the gradient offset
But I need to figure out how to choose the right point for each plane to get the right rotation, I haven't figured this part out yet unfortunately.
From these calculations do you have any idea how I can get the 2 points on each plane? https://pastebin.com/Jfqh9WY8
Pastebin.com is the number one paste tool since 2002. Pastebin is a website where you can store text online for a set period of time.
@slow ermine do you know blender?
Yes
I can show you how how to do the gradiend thing in shader if you want. but it's not your method.
@slow ermine Has your question been resolved?
So basically you have a 2d plane of a 3d space and you want to assign one color to all points in one semi-space, and another color to all points in the opposite semi-space. Is that right?
Are you looking for a solution for cube specifically, or do you want the most generalised version?
@slow ermine Anyways, here's an idea that might help with rotation of Gui. Let's say the normal of a given face is $q \in \mathbb{R}^3$. Let's say that the normal of separating plane is $p \in \mathbb{R}^3$. In order to calculate the vector parallel to the intersection of the face and the plane, consider the vector product of $p$ and $q$: $v=[p,q]$. The angle between $v$ and an appropriate edge of the face is the angle of rotation of your GUI.
EQUENOS
So yeah the angle between v and w will be the angle of rotation of your GUI
Offsetting the gui should be easy
That makes sense, but how do I know which edge to measure as W?
It depends on which edge the GUI sees as the bottom line
Attach a surface GUI, add a black frame with scale coords {0, 0} and you'll see the "upper left corner of the face"
The lower edge would be the w vector of that face
Alright and after figuring out which edge is the bottom, how would I define it exactly?
Assuming you know the CFrame and size of your cube, it's easy to calculate the coordinates of all 8 vertices: v_1, ..., v_8
After that the dege between say vertices 1 and 2 would be v_2 - v_1
I guess what I mean to say is how do I get this point so I can calculate the angle?
You don't need that point
The angle between v and w is equal to $arccos\frac{(w, v)}{|w|\cdot|v|}$
Oh I must've misunderstood then sorry
EQUENOS
Or any other formula you find convenient
Would v be the angle of the 2 intersecting points on the face?
v would be the vector such that if you draw it at one intersection point on the edge, it will point to another such intersection point
Oh okay I understand what you mean now
What calculation would you use to determine which face a point is on?
The function I use doesn't seem to work as I intended:
function getPointsOnFace(cube, point)
local cubeCFrame = cube.CFrame
local cubeSize = cube.Size
local localPoint = cubeCFrame:PointToObjectSpace(point)
local halfSizeX = cubeSize.X / 2
local halfSizeY = cubeSize.Y / 2
local halfSizeZ = cubeSize.Z / 2
if localPoint.Z >= halfSizeZ then
return "Front"
elseif localPoint.Z <= -halfSizeZ then
return "Back"
elseif localPoint.X <= -halfSizeX then
return "Left"
elseif localPoint.X >= halfSizeX then
return "Right"
elseif localPoint.Y >= halfSizeY then
return "Top"
elseif localPoint.Y <= -halfSizeY then
return "Bottom"
else
return nil
end
end
You don't need that function as far as I can tell
v = p × q, where × denotes the vector product
guiAngle = arccos((v, w)/(|v| |w|)), where (•,•) denotes the scalar product
In other words, v = (p.y q.z - p.z q.y, q.z p.x - q.x p.z, p.x q.y - p.y q.x)
The math is a a bit advanced for my current understanding
Essentially the vector product p×q is an operation that constructs a vector perpendicular to both p and q
So if p and q are normal vectors of 2 planes, then their vector product is a vector parallel to the intersection line of those planes
Okay
currently in the 7th grade, but according to standardized tests my math level was that of a college student
so can i try to tackle one of your problems?
in extremely good at algebra
Of course, you can select any channel with a problem that you find hard enough
Feel free to help other people here, there're plenty of channels :)
but can i help him too, or only one person can?
The wording is a bit confusing to me, im more of a visual leaner, can I get a bit more detail that way by chance?
Yes, you can help Burdy as well
Sure, here's a pic
Blue vector and teal vector are normals to the given planes
Orange vector is their × product
It happens to perfectly align with the red line (intersection of planes)
A face of the cube is a plane. The other plane in our case is the separator plane
(The plane that cuts the cube into red and green parts)
yo here is a more modified version of your function, given that you already have cube's dimensions and its position, you can just simply check local coordinates of point relative to cube function getPointsOnFace(cube, point)
local localPoint = cube.CFrame:pointToObjectSpace(point)
local halfSizeX = cube.Size.X / 2
local halfSizeY = cube.Size.Y / 2
local halfSizeZ = cube.Size.Z / 2
if math.abs(localPoint.Z) >= halfSizeZ then
return localPoint.Z > 0 and "Front" or "Back"
elseif math.abs(localPoint.X) >= halfSizeX then
return localPoint.X > 0 and "Right" or "Left"
elseif math.abs(localPoint.Y) >= halfSizeY then
return localPoint.Y > 0 and "Top" or "Bottom"
end
return nil -- Point is inside the cube
end
seems like ur working with a function to determine which face of a cube a point is on?
or am i tripping
im so clueless 😭
you guys there?
I think I get what you mean generally, but the way you're explaining the normals for the plains is a bit confusing
Its possibly because I only understand normals in a specific programming language
Its not pretty, but I was able to add the intersection points and separate them into tables to define which faces the intersection shares. take a look:
https://pastebin.com/jQcdQRzx
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It was able to successfully separate the points from any face I decide to select. The blue shows the points touching the bottom face.
@eternal stone
local function convertPointVectorsToRotation(faceName, point1, point2)
local halfSize = Cube.Size / 2
-- Define the bottom edge vector based on the face name
local bottomEdgeVector
-- Determine the bottom edge vector based on the specified face
if faceName == "Front" then
bottomEdgeVector = Vector3.new(halfSize.X * 2, 0, 0)
elseif faceName == "Back" then
bottomEdgeVector = Vector3.new(halfSize.X * 2, 0, 0)
elseif faceName == "Left" then
bottomEdgeVector = Vector3.new(0, 0, halfSize.Z * 2)
elseif faceName == "Right" then
bottomEdgeVector = Vector3.new(0, 0, halfSize.Z * 2)
elseif faceName == "Top" then
bottomEdgeVector = Vector3.new(halfSize.X * 2, 0, 0)
elseif faceName == "Bottom" then
bottomEdgeVector = Vector3.new(halfSize.X * 2, 0, 0)
end
-- Calculate the vector from point1 to point2
local vectorAB = point2 - point1
-- Calculate the angle between the two vectors using the dot product
local dotProduct = vectorAB.Unit:Dot(bottomEdgeVector.Unit)
local angleRadians = math.acos(dotProduct) -- Get the angle in radians
local angleDegrees = math.deg(angleRadians) -- Convert to degrees
return angleDegrees
end
can somwone. help me
Do you see something wrong with how I calculated the rotation?
It's probably the direction of vectorAB that messes things up
Please may someone help me
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I've tried testing each face separately by changing the order of the vectorAB but it doesn't really fix the problem, maybe there's something else wrong?
Thank you
Hm, one of the issues is that acos(x) returns an angle between 0 and pi, however, in reality we may need the angle between -pi and 0, depending on the direction of rotation
So perhaps atan2 would be a more suitable function
Actually, roblox studio provides the :Angle() method for Vector3 objects
So I guess we want bottomEdgeVector:Angle(vectorAB, q), where q is the normal of the face we're working with
Alright, I implemented it. And the speed at which the angle is adjusting seems equal to how much I rotate the cube which is good. However, there's 2 problems:
-
The angle does a 180 degree rotation when one of the points of VectorAB reaches the bottom right point of the bottomEdgeVector (the purple line)
-
The rotation of the gradient was not quite lined up with the rotation of VectorAB still.
I was, however able to keep the rotation perpendicular to VectorAB by changing:
"bottomEdgeVector:Angle(vectorAB, q)" calculation so that the result is negative:
"-(bottomEdgeVector:Angle(vectorAB, q))"
Which gave me this result,
I think its very close, but here is the new function. It defines the bottom edge vector differently by first getting the bottom left point and the bottom right point. Idk if there's a better way?
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I think the rotation flipping has to do with the vector calculation
Because flipping VectorAB
From: (point2 - point1)
To: (point1 - point2)
flips the gradient as well, as you see from the video
So basically flipping the points changes the direction of VectorAB
Yes, of course
If the vector is flipped then the rotation is off by 180 degress
Are you sure point1 and point2 are always in correct order?
Hmm they do seem to swap places here.
The red is point1 and the blue is point2
But why?
It depends on your implementation
Well the script is 400 lines long currently, so its a bit difficult to decipher where exactly it does wrong. But I debugged to make sure the points being sent were always the same instances and it was true. So I believe the problem is this block of code where my intersect calculations is for some reason swapping the existing positions of the points when the cube orientation reaches a certain point
https://pastebin.com/XQVVTpc5
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oof
I assume pairs(edges) messes up the order?
Maybe ipairs(edges) could do the trick
Didn't fix :/

@slow ermine Has your question been resolved?
I figured out why they were flipping. I had set the function to loop through the edges of the face in a specific order, which was causing the index of the points to change positions making them swap orders
Just need to figure out why the vector angle calculation is off now... any ideas?
I don't see the issue
What do you mean the vector angle calculation is wrong?
Its all good I figured it out
Right, anything else?
If not, you can close this channel by typing .close
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Oh, nice, congratulations!
And the rotation was off because the canvas size of my surface Gui was 800 by 600 😂
Did so much worrying about that for nothing
Anyways I appreciate the help 👍
Lol
Cross multiply to get quadratic
And apply quadratic formula
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3-96(b)
I do not understand the notation of Z sub 6 or [n] sub 6 and cant find it anywhere else in the book
Z_6 is the set {[0], [1], …, [5]}
[k] is the set of numbers of form 6a + k for some integer a (they have k remainder when divided by 6)
i.e. the numbers that are k mod 6
oh so [0] = {0, 6, 12, 18, ...}?
yea
oh by [k] i meant [k]_6
yea
i dont really understand what the functio nis doing, then
what would [4]_6 [n]_6 look like?
or does it not matter for the sake of the problem to show it isn't injective
well it’s just [4n]_6
i see
sorry im still stuck on how to show a situation where [n]_6 is not equal to [m]_6 but f([n]_6) = f([m]_6)
ohh [0]_6 is not equal to [3]_6 but f([0]_6) = f([3]_6) 😁
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Hello could I get some help with this question?
find the parts that look like parts of circles
break the shape into semicircle arcs
and then what
find the arclength
do you know how to find the perimeter of an arc
no clue
yes
do you know how to find the perimeter of a semicircle then
no
like the arc part (not including the diameter)
I have no clue 😭
ok
What are the measures of all those smol squares tho? Is it mentioned?
I have solved a similar question in the past so i thought i could solve this one too but the length is not mentioned so ig it's gonna be too hard for me
Like this, if measures were given it would have been possible for me 🫠
12th 🫠
So abt to gradute highschool?
Do you take math?
Umm just a guess but can't we just "assume" each square is 1 unit tho like cm or m 🫠 and then solve?
yes
Like we do in a unit circle thing
Yup i have got maths even tho i didn't want to take it 😭 i was studying all night lol
Lemme try, gimme a min ig
Did you find out?
Yeah i was just drawing the damn figure, i solved 1/4 i would say
You don't have to do it
Lemme try, just a min
ok
what abt this hehe
See there are 4 "semi circles" in it of 12 units, 6 units, 2 units and 8 units. So you just use the circumference formula on each of them "separately" and divide each of them with 2 as well (because they are all semicircles yk)
ok
Wait what grade are you in btw? Coz this is really easy, lemme do it in one sec
See in the first row, x value is given i.e. 0
mhm
So put that in our main equation i.e. y = 1.5x + 2
So that gives us
Y = 1.5 * 0 + 2
Y = 0 + 2 = 2
So Y = 2 is the answer for the first row
In the second row we got Y's value instead of X. So just put Y's value in our main equation
5 = 1.5x + 2
Subtract 2 from both sides
3 = 1.5x
Divide both sides by 1.5
2 = x
2
(i make silly mistakes sometimes so i can be wrong but nah i am sure this is correct
wait so what are the next 3?
For the next one
This is for the 2nd one
2
Yup (if i didn't make some silly mistake 😔)
Nope the sequence of the answer is
2
2
6.5
1
Yeah it should be correct 🙂
Oh it was
Yup gn mate
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Please help how does this make sense
what's average rate of change formula?
bro what
all i need to do is find how many points the slope is zero
and the solution isnt explaining how that came to fruition
it draws a line with 3 points on it and it says the answer is two?
yes
the interval is [b, 1]
we know the point b must lie on the same y as the point (1, f(x))
so just draw a line
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... just look at the formula and the interval and you'll understand
.close
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help someone has chegg premium? cause i really need the answer for this one or If you can solve this that would be great
First of all physics
Second of all use kirchoffs loop rule
i tried and i get -277.5 its not close to the actual final asnwer
could u try and solve it?
Show your working
heyy
Which loop did you use?
He said he doesn't want current sources
Use source transformation
Uk how to do that?
@quiet jungle
i dont unless u show me
plss
solve it
im so desperate right now
We should be helping not solving
Ok si
So*
Source transformation
Let me explain
If u can find a current source parallel to resistor
Then u can use source transformation
To convert it into voltage source with resistor in series
In here u see
5 uA and 2Mohm in parallel
Use this
v=ir
10 v
hmm??
Remove the 2Mohm resistor and 5uA current source
Add them in the circuit in series
okok thank you
ok so the 5 becomes 10 after transformation
next?
Now it's simple enough right
Simple circuit
Add all voltages
Add all resistors
Solve
Idk I didn't solve
Adding doesn't mean summing up
U have to check
Sign convention
U missed there maybe
like in the final answer here is -577.5
i didnt miss anything i extracted the other side to get i
then divide both sides
Send process once
well i might miss the signs
Well no
Sorry I messed up
I sent the wrong figure
Like this sry
@quiet jungle
add all v and r?
KVL?
What happnd
its KVL
all the 12 7 10 is V and the rest are i
sorry
ok ok
I'm not able to find the thing u need to solve
U are not able to solve cuz u r not familiar with basics
Idk how to explain
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You are given two coordinate system in three dimensional space. You are also given the general matrix of transformation of them (a column of a1, a2 and a3, then with b and with c). Under which conditions the second coordinate system will also be Cartesian system, if we know that the first one is the Cartesian system?
I know how to do that for the 2d space, by I can't prove it for the 3d space
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.reopen
✅
Lines are perpendicular and so on
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how to compute this quickly?
it says that we can ignore the terms of degree >5, but why?
its a good enough approx without them
is that because of the o(x^5) that we choose to ignore the terms of degree >5 ?
Essentially the o(x^5) captures the rest of the terms in the series.
yeah
Because the actual series is infinite
so o(x^5) represents a polynomial that for x-->0 is "smaller" than x^5
so any polynomial with degree >5
i think i understand but i need the steps...
You actually know exactly what the polynomial is, since it's actually just the Taylor series of sin(x) at x=0 inside ()^3
but if we actually expanded this, then it would be like (a+b+c+d)^3 and 3a^2c = 3x^2 * o(x^5) = o(x^7) would be the little o with the lowest degree
so we'd have to ignore the terms with degree >7, not >5...
I think if you move the little o out of the power, the lowest degree that doesn't get fully accounted for is x^9, since the lowest degree that doesn't get included from the Taylor series is x^7. And the lowest combination with it would be x*x*x^7=x^9
@fossil wedge Has your question been resolved?
sorry i dont understand
Tbh. I'm not really familiar with the little O notation, only big O, but if I understand it correctly, x^9 being not fully accounted for would make o(x^7) as you suggested.
okay thank you!
The difference is only that you expanded o(x^5), while I expanded the lowest degree of the residual series of o(x^5)
it is good also to fisrst put x^3 in factor of all
so this would just become x^3 - x^5/2 + o(x^7)
that becomes x^3 - x^5/2 + o(x^5)
i did a^3 + 3a^2b + 3a^2c
i was trying to solve this actually
i dont know how far i have to expand it
This screams L'Hopital, doesn't it? 😅
idk, i was trying to use taylor series...
anyway i think i solved it
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Ping a helper not me
ok