#help-39
1 messages · Page 303 of 1
well simplify it first
1/3 b
simplify what's in the root first
but what about 4/9
$\sqrt{\frac{4}{9}b^2 - \frac{3b^2}{9}}$
1 divided by 0 equals Infinity
to be able to compute this
but do we have to simplify that in the root
you should simplify what's in the root first
cant we do it after
yea we have to
you can't have $\sqrt{A - B} = \sqrt{A} - \sqrt{B}$
1 divided by 0 equals Infinity
it's kinda clear here
1 divided by 0 equals Infinity
yea
it depends tho, but mostly you simplify in the roots first
it makes things nicer to handle like what you had here
you done @daring bay?
anymore questions to ask us?
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aight then
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I need a hint, how do I evaluate the limit of
$\frac{\left(1+x\right)^{\frac{1}{x}}-e}{x}$
as x approaches 0
Aorts
hmmm
i remember this question..jee advanced right
yep
let me try
this is a defn of derivative technically, though im not sure whether it helps
oh yes
I took the derivative but it's blightful
its the derivative of (1+x)^(1/x) at 0, if you extend it continuously at 0
we can solve by definition of derivative
if you're okay with differentiating that thing, then i think its the fastest sol
yeah but the derivative is just a worse problem to handle imo
it should be just e^ln(1+x)/x and then chain rule
hmm, right, we would have to take the lim of derivative and it might not be simpler
use logarithmic diff.
gang I did just that
yep
when x approaches 0
are you okay with taylor expanding?
write the (1+x)^1/x as e
I'm okay but how would we taylor expand (1+x)^1/x 
wdym?
yeah this is what i did also ^^
its just $\exp\left(\frac{\ln\left(1+x\right)}{x}\right)$
after differentiation
MathIsAlwaysRight
oh, i didnt actually fully differentiate it because of my laziness, but then it might actually work
or this + taylor, i tested out this one and it works
whats exp
e^sth
oh right, I hadn't considered expanding that
oj
I moved on to differentiating it entirely
yess it works
thank you all!!
I will go ahead and close the channel then 
.close
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How do you find the domain of a function from a graph?
go along the x axis and ask yourself whether there is a point on the graph associated that with each x value
these are not called functions (b and c)
see what layla said.
1 or 2?
at the point 1 on the x axis, there are two points straight above or below 1
so 1 is in the domain
at the 2 there is also a point on the graph
at 3 there is not
So would it be 2 since it's the highest number?
well all the real numbers <= 2 are in the relation's domain
the numbers > 2 are not
there is a point on the graph that intersects this vertical line, so 1 is in the domain
so there are no such points when you put the line at 3 instead of 1, so 3 is not in the domain
same as what i said before, just with a picture this time
it means that at every real number z, there is a point (x,y) on the graph with x = z
yep
Do you know hit and try method?
almost
yes, but also it looks like -4 <= x <= 0
Would the range be 4 <= x <= 0
Ohhh whoops
wsp guys im new to this server
Since it dosent say 4 would I be allowed to say 3? Because its really just a guess
sometimes you can't be precise but i'd say it should really be 4 here
like it's a circle with radius 2
so the diameter is 4
yay
I'm probably gonna be back in this server about 20 times tonight

I kinda delayed studying now my test is tomorrow 
we've all been there
Well I'm back
For 13
I looked at the solution and it uses a formula ds/dt
What does d stand for?? I know s and t but how do I type that in
d by itself means "very very small piece of something". dy/dx is the derivative of the function y with respect to x
ds/dt is the derivative of displacement with respect to time.
do you know what that is equivalent to?
displacement? I have no clue
:((
There are no other numbers in the equation or anything
well yes you're supposed to use calculus here.
here's a useful list
d(displacement)/dt = velocity (v)
d(velocity)/dt = acceleration (a)
and you can reverse these operations with antiderivatives.
d(smth)/dt is the derivative of smth with respect to time.
the derivative of displacement with respect to time is velocity. or speed
here, you are given a function of displacement
Integration!!
and is directly asking you for speed of the moving thing
now that you know that the derivative of displacement is speed
you can get a function of speed by differentiating the displacement function you're given!
I will explain again perhaps you're back-reading/didnt get something.
we are given a function of displacement,
s= 0.25 e^t
we are asked for velocity. the releationship of velocity and displacement is quite the famous one! velocity is the derivative of displacement.
since we're given a function of displacement, if we find the derivative of it, we can get the function of velocity. which will solve alll of our problems!
displacement ---> velocity ---> acceleration
the arrows represent differentiation/derivative.
@sinful snow Is it IGCSE book? Something
@sinful snow Has your question been resolved?
I'm still so confused
sorry for taking so long I had to grab smth
I'm afraid you're lacking some essentials covered in early calculus and early kinematics.
I'm not sure what I can do about that except i can redirect you to a youtube video,.
I really hate this book, the examples they give us are simple then the questions have no correlation
@cinder flower can we solve this without calculus (13)
I mean the whole velocity is the derivative of displacement shtick is covered in physics as well.
actually- it shouldnt be covered in math but
oh well- it uses calculus!


you said your exam is tomorrow?
Yea
have you tried studying the material before- solving?
weird question but i wanna make sure
Slayla and carla you know many concepts of maths, you guys are at which year?
well the questionalso expects you to graph
are you familiar with that
like graph of exponentials.
Yeah I've done a bunch of graphing
do you know how to differnetiate
take derivatives of stuff
I don't
I'm afraid you cant solve that problem then
is there any way you can check your syllabus and see if it has calculus in it
So far we've done slgerbra 1,2 and 3
This chapter is functions
Maybe the problem is that we don't go by book chapter, like it's chapter 1, 2,12 then 8
oooooh
well yeah the chapter wont include differentiation. but the question does expect you to know how to differentiate
so ignore it
move on
solve the other ones
and see if you face any problems
I cna give you the function of velocity and then you can graph it i guess. thats one part your chapter covers
greatest of luck
Thank uuuu
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@desert silo Has your question been resolved?
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Instructions are to rewrite the expression in terms of the first power of the cosine
At first glance I thought this problem requires me to use the Half-Angle Identity
But I don’t think that’s right
could use the cos(a)cos(b) formula if you have it
Huh
the cos(a)cos(b) + sin(a)sin(b) ?
maybe the power reducing identity could work
although that's basically taken from the cos(a)cos(b) thingy
this led me to realize that idk what the half-angle identity exactly is, and when i should use it
😭
use the formula for cos(2x)
If cos(2x) = cos^2(x) - sin^2(x)
then cos^2(x) = cos(2x) + sin^2(x)
you sub pi/2 into x @dark dagger
mb haha
no worries
also 1 + cos(2x) = 2cos²(x)
so cos²(x/2) = ( 1+cos(x) )/2
ans could be in this form as well
@dark dagger Has your question been resolved?
Btw is anyone able to answer this :(
$\cos(\frac{x}{2}) = \sqrt{\frac{1+\cos(x)}{2}}$
something similar for sin and tan
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am i right to say =(2/3)
ayep
Did you use the Leibniz integral rule
Yeah you're right
thats what i did
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Yeah it's fine
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Hello , can someone explain how to solve this by using equation appraoch
that's just pure grammar 🥀
Ig misprinted
this is correct grammar
I did
using gap method already
I just wanna know the equation approach
I mean I solved using that
We put 14 gaps
and arrange 10 people in the 15 created gaps
15p10ig
you mean you want a generalization?
you really want to make an equation out of this?
oh
I didn't get the first inequality x1,x11 greater than equalt to 0
and rest greater than equal to 1
(ignore capitalization , pure accident
are the people independent?
well read the question , my guess is as good as urs
tbh I don't know what that means
dependent on whom?
I'm forgetting terminology, I meant distinct
yeah ig
||two persons is actually grammatically correct, but rarely used (usually in legal documents, laws, on signs, etc.)||
unless specified otherwise it shud be standard assumption
are u fr?
x1 is number of empty seats before first person
x2 is number of empty seats between 1st and 2nd
all th eway to x11 being the number of empty seats after last person
because no two people can sit in consecutive seats then there must be at least one empty seat between any two people
so x2 to x10 are 1 or more
x0 or x11 can be 0 because there can be no empty seats before/after the first/last person
there is no standard
||wait really?||
Okay......well you explain the whole solution after this
sometimes the people receiving a donut are distinct but the people who don't are not
well now that i have clearly stated there is diff so yea........
||yes, mostly to emphasize individuals separately rather than as a group of 'people'. But anyway I won't clutter this help channel anymore. Sorry Agape||
someone pls explain this
how to proceed after this
Omg your grammar
take it else where
im assuming its the same method
this attitude, man
🤷
so demanding
Sowwy
I just thought
She thought I was just solve afterward
so I made it clear
well if I send the entire solution would u be able to tell smth
probably
I think the point is you do the work and people guide you when you get stuck and/or explain the reasoning
well..... its just that I already tried lol
I don't ask without trying
you subtract 1 from x2 to x10 to make them non negative
then do stars & bars
you should define your x_i's
this is probably what xi is representing
just a guess
Jeez it's not my writing , I am following some unfortunate books
I am pretty sure you r right
cuz then the solution makes sense
oh duh the watermarks lol
Listen lets not talk abt my pirating habits
too poor man
Anyway ty to all
even to mr grammar who enlightenet me abt two persons lol
.close
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Hello everyone, Am trying to solve a CTF which requires me to prove ( that is not the part of concern) that a point (x,y) exists on a curve and curve has a eqaution of y^2=x^3+ax+b (a and b are given), but the thing is they want me to satisfy few relations y^2=x^3+ax+b mod p1, y^2=x^3+ax+b mod p2....so on where p1,p2... are prime is there a way i can find (x,y) i will use sageMaths to find the solution but like what should be the approch to this?
Thanks 😄
also that (x,y) should be a integer pair
hmm i see an elliptic curve
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anyone by any chance knows how to fix this really small tiny iny issue?
number aint even that big cmon
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I need help with solving for angle of elevation/depression
I know it's not a very specific question, I just don't understand how to solve for it in general and none of my resources are helping me
angle of depression is the angle by which your line of sight goes down to look at an object
rest is trigonometry and depends on the structure of the question
I get that (mostly) but I can't tell where exactly you'd be "looking down" at something from
Or how to properly do inverse functions
angle of elevation 'from the boat' to the top of the tower
you're standing at the boat and need to look up at the yop of the tower
the angle by which your neck moves up
is the elevation
Asking the actual question right away is more likely to get responses.
Asking "Can I ask...?" or "Does anyone know about...?" doesn't give people enough information to decide whether they can help, and answering can feel like a promise to help with the actual question, which they might find themselves unable to.
(In the future, please make the first message you send the actual question since that's what the bot pins. This saves us the effort of having to change the pin manually.)
Ah, I'm sorry
It's my first time asking for help and I wasn't 100% sure how to ask what I needed
.close
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What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
1
try writing it in exponential form and graphing it
x+5=2^6/2^x ?
but i havent studied graphs of exponential
isnt therre other way?
you don't know what 2^-x looks like?
it starts from + inf and decreasing?
yes
if you know what 2^x looks like it's just the same thing but reflected over the y axis
the factor of 2^6 will stretch it of course in our example
ok
but like i need to solve qs withouut graph
i mean what class is this for
and how do you know you need to do this without a graph
11th
that's not what i meant but ok
its a qs of 1st ch and we have not been taught to solve qs graphically yet
what u meant
in my coutry there arent diff course
this is js jee math
its diff from most countries
the name of ch is basic maths
i mean i'd be willing to bet a solution key would graph it
it isn't complicated to do so
just a rough sketch
but the thing is my teacher hasnt taught graphs yet and even if i know the graph how would i see solution on pen paper?
from rough sketch how will i know exact point of intersection
you don't know how to graph a linear function and a logarithmic function?
or an exponential?
you don't need to find it
that's the point of graphing
i js kniw rough and only basic
hm yea
2^6-x will start 6 unit left of y axis?
and decrease??
not sure what you mean by this
nvm wait
yea looks good
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hello whats the derivative of (c-2)/2 x^2
i had this in an exam and i did something wrong
i really wanna know what i did wrong and it really frustrates me
do you mean c-2 over 2x^2 or c-2 over 2 times x^2
no like
$\frac{x^2(c-2)}{2}$
This?
2x^2?
and after the fraction theres a x^2
no just a 2
$\frac{c-2}{2x^2}$
acacialog123
oh
no
Minhh
so you derive the x^2 first
This?
do you know how to do that
the x ^2 is after the fraction
yes
i just did the fraction times 2/1
is that correct
Ts?
the derivative of x^2 is 2x.
no
Then which formula so vague
so its ((c-2)/2)*2x
$\frac{c-2}{2}{x^2}$
law
ok thats clearer
so whats the derivative of x^2
2x
so i just multiplied the whole fraction times 2
ok what do you think would happen next
So this is literally the same man
and we have 4/4 then
the 2 from the den cancels
it leaves you with (c-2)x
which is your derivative
oh shit
okay
i thought
the 4/4 cancels
and we just have c left
😭
it would? or no
wouldnt
Wdym?
@daring bay do you agree with this answer
oh
Brackets are inferred in this case
Depending on how you multiply the fraction by x^2
If there weren’t parenthesis here, in this way of writing the problem, it would be a different fraction to begin with
So in that sense it’ll be different
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can anyone help me solve this limt
small hint plz
lopital
or we think the french only know how to say baguette and not do maths and we try this without L'Hôpital's
Try and formulate a grammatical sentence and try again 
sabotaged by a comma
But yh, have you tried L'Hôpital yet? @boreal slate
L🏥
"Perhaps we assume the French are better at baking baguettes than solving equations; let's attempt this without using L'Hôpital's Rule." Fit bro's fancy better? English pedants in a maths server 💀
bigot
@pastel umbra @honest spear
i aint sure lhoptials is the right choice here..
or maybe im doin it wrong
lhopital always works with enough confidence
Follow-up question - does that limit actually exist?
should be ln x + 1 within the brackets
perhaps not
Check the left and right side of those limits
your numerator should be $\ln(x)+1$
Nyxzore
not -
youre right
lmao so i still get 0/0
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Helloo what's this formula for? I heard it has something to do with the ratio but i forgot 😅
It’s just a sequence
If that’s an inequality, then it’s a family of sequences with that as the lower bound
Nothing special really if I’m not mistaken
@ashen slate Has your question been resolved?
Ouh, would u mind telling/showing me an example of a question that requires us to use that formula?
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not sure how to do this
Have you drawn out the diagram and all the relevent forces, including friction?
yeah
lemme redraw it on paint
cus i have it on apper
paper
not sure what to do now
As you need the ladder to be stationary, consider the moments about the point where it contacts the ground, to find X
Are you working on that?
You balance the vertical forces, so R = W, then use the moment to calculate X from W, then balance horizontal forces using X = mu R
so i will get something in terms of R = mu R?
Something in terms of f(W) = mu R
Then the mass will apparently cancel, I haven't done these in a while
How's it going?
Yes you'll get k*R = mu R, then equate them to get the equation it wants
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show your work 
after squaring
try x^2 - y^2 = xy^2 - yx^2 and factoring (its a small trick that will let you get the desired derrivative)
you did (x-y)/(y-x)=1 when it should be -1
the -ve ofc
yep
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how would these 2 graphs look like if i would graphical intergrade them?
what exactly do you mean?
Like interpolate between them?
ugh i mean these are f(x) right now and i want to draw F(x)
idk the english words for it
integrate?
oh
could be yea
Not this?
absolutely
You want us to teach you how to integrate or how to draw the integral numerically?
how to draw the integral of these graphs
does that makes sense?
I don't have much experience drawing integrals numerically
aight nw
You could use the graphs to determine the equation, integrate that, then plot it
how could i determine the equation of this graph?
Graphically integrate is a new term
with the roots as example?
Left looks like cubic integrating it will give graph of a quartic with 3 turning points
prolly yea but i think i give up on that one, it will most likely not get asked in examen
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sigma is the standard deviation
the red vertical axes show $\mu-\sigma$ and $\mu+\sigma$
gribble19
The standard deviation is a measure of "spreadness". A large standard deviation means you are likely to sample far away from the mean
Like, in this case, if you rolled a die.
I think, judging by that bottom axis, this is based on dice rolls
Large standard deviation: You will probably not roll close to the mean. The data is very spread out.
Small SD: You will probably roll close to the mean. The data is very concentrated.
That is, you are saying if the mean is 0 and σ is small, I often draw numbers like 0.5,0.2,0.1 if the mean is 0 and σ is large, you often draw numbers like 3,2.5,4
this might help illustrate
Yeah pretty well said
SD and variance measure the same thing, if you know variance
many values are often close by, but it is not guaranteed and it is not a “always valid” rule?
SD has the same units as the data though, so it's used in more calculations
I ready this
.
What is not guarenteed?
it is not always true that the values often come out in that range
No not guaranteed. SD just controls how probable it is
if you roll a die, there is a 68,27% chance the result is between the red lines
so it is not guaranteed it will be in there
but lets say we have two different sets of values
A:
1: 10
2: 10
3: 10
4: 10
5: 10
B:
1: 1
2: 4
3: 40
4: 4
5: 1
both A and B have the same Mean, but they have a different Standard Deviation
when you roll a die in A, the chance of getting a result far away from the mean (so 1 or 5) is much bigger than in B
Why 68,27%
actually i have to note, this is only the case if the distribution is a normal distribution
so it wouldn't apply in the example you showed
@rough stream @hollow magnet So small σ → more concentrated values near μ, large σ → more dispersed values μ. But then what is
μ±σ (the arrows in my image)?
would these be the two intervals where the values fall?
The arrows are just μ±σ
A place where a lot of values happen to be
I think they just want to give you a picture to see what μ and σ can look like
@green aurora
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idk if i am being slow but how would i do this i just have no idea where to start
$$\prod_{k=1}^{n-1} \frac{k+1}{k}$$
akeanti💕
it simplifies
'produit telescopique'
$$\left(\frac{2}{1}\right) \times \left(\frac{3}{2}\right) \times \left(\frac{4}{3}\right) \times \dots \times \left(\frac{n-1}{n-2}\right) \times \left(\frac{n}{n-1}\right)$$
akeanti💕
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Hello I need help with something
I’m trying to visualize the geometry of these unit vectors and how the come about
In terms of the definition of a derivative
Each one?
Tbh that would be great
For the tangent, you can picture it similarly to how to the derivative of an equation is the tangent of the graph
So the tangent is the direction (although not directional) of travel
Question tho, why would the vector not be measured from the origin and be tangent to the graph?
If you did define it that way would it would give the same tangents
As it doesn't measure the position of the vector but its change
So you’re saying the position wouldn’t matter and that’s why
Picture the discrete delta y delta x method of approximating a tangent on a graph
so you're moving a small amount along the graph using that to approximate the slope
it is the same for the vector definition, where you start and make a small movement using the equation for r, then measure the direction
so the derivative gives that exact value
the normal is defined as being perpendicular to the tangent
Yes but why
because that is what a normal vector is
that is just an equation for finding the normal
How do you know that using the derivative definition
Because it’s defined as the unit tangent vector’s derivative normalized
T’(t)/|T’(t)|
You’re deriving T’(t)
Yes
So like
I'm trying to think of an intuitive way
The derivative of the graph of the unit tangent vectors for all t???
The normal is again the direction of change of the tangent. Suppose at some point the tangent is pointing at (0,1) and then shortly after pointing at (0.01, 0.99)
I'm trying to explain it without drawing it
Visually you would intuit that the shape has to have 'bent' in the direction of the normal and so the change of the tangent can measure the normal
@south ice Has your question been resolved?
Look
Is it the same logic for why the unit tangent vector is normal to the position vector at some point t
It is if you're considering circular motion
@south ice Has your question been resolved?
Is the unit tangent vector not always normal to the position vector at time t?
I see. One thing tho. Can you think of the unit normal vector, as the full definition of the derivative (limit of the difference quotient as h approaches 0) for some point t on the derivative function ?
I don't know what you mean by that
Then that vector you get you just divide by its magnitude
The normal from the derivative gives the direction, then you normalise it to length 1 using the division
What r u guys talking abt I can help a lil
Trying to understand the unit normal vectors intuitively
You can check pinned messages to see the topic of discussion
My mom just told me to tell u this bc she's a teacher
So
Okay
Unit normal vector or dt is always a orthogonal curve and also unit tangent vector T is contained in the vector substance defind by the two units...... Idk if she's correct well she should bc she's a teacher
If u don't understand I'll tell her

I think you misheard her because vector substance doesn't mean anything
Probably
What I was asking tho is how to think of all this in terms of derivatives, like when we define the unit normal vector to be: N(t) = T’(t)/|T’(t)|
How should we imagine the derivative of T(t) on the graph? And why does that give us a vector that’s directly perpendicular to it when divided by its magnitude ?
Think about it instead as the second derivative of the position vector
Just ask her this please
If you can
Hmm alright?
Given the calculation above the normal is pointing toward the 'interior' of the curve at that point, and so describes the behaviour of the curve in the same way the second derivative of an equation describes the behaviour of the slope, in that it curves up or down
You don't have to help in this channel 🙂
Idk
I mean
I’m trying to think of how you’re supposed to graph the derivative functions
Then from there
How the derivative behaves
Like the vector at that point
Okay
If you're trying it out on a circle at the origin then the tangent derivative is another circle at the origin that starts 90 degrees from the original
And the unit normal the unit circle starting another 90 degrees from the tangent circle's start
Right she told me smth
Can I have this channel?
Lemme ask you this, what’s the point of the unit normal vector ? To show how a particle is turning correct ? So why is the derivative of the unit tangent vector / by its magnitude give you that information????
Ong
The unit normal is very important, you can look at lots of computer science examples to see why
And then why is that turning defined by a vector perpendicular to the tangent vector ?
Faxx🔥🔥🔥
Lol
Take some point P1=(S1) on a curve C. Let T1 be the unit tangent at this point. Now move a tiny distance along the curve to get to the point P2=c (s2) and let T2 be the unit tangent at this point now draw the vector V=T2-T1 if P1 and P2 are very close together T1 and T2 will be almost equal and V will be roughly perpendicular to both of them because the triangle with sides T1 and T2 will be almost isosceles and very skinny.......... She wrote this btw

Seems like you're being deliberately annoying, you can have some time to think about not intruding in other channels 

I was gonna say that but I was writing smth down
Gng why am I even writing this down
Lol
War beast do u understand
Or just send a pic of the hw
So I can understand better
Or just show my mother
This will be much better ngl
Why do we consider the unit tangent vectors and not just the vectors themselves without normalizing them?
There isn’t any because my questions are conceptual
Lemme ask her
Alright thanks
We normalise the vectors to simplify the mathematics
As all normalised vectors have length one
If the normal hadn't been normalised then the 3rd equation (binormal) wouldnt be correct and we would have to scale it down
Wait let’s get to binomial after the unit and normal
So wait
Normal tangent vector: tells us how a particle’s direction changes
Unit normal vector: tells us how a particle is turning
Correct
The binormal
@full wadi
Okay so
Alright so when we talk about the unit tangent vector
We are considering the velocity of the position function
Then we normalize that velocity vector
@full wadi right
unit tangent vector = unit velocity vector
If I’m not wrong
I have never personally used the binormal for anything
unit just means normalised to length one
In Riemnannian geometry for example one defines the unit normal of a local parametrization (under the right circumstances) as
N:=∂1X×∂2X|∂1X×∂2X|
As the name says, it is a unit vector. I mean, one advantage of normalizing basis vectors is that we can easily calculate the coefficients in the linear combinations, but I think there are more. Sorry it took long she's a slow typer
Tell her she can do LaTeX on here!
No worries at all tell her I appreciate her replies
@full wadi Okay, so do we care about speed here then? When talking about where a particle is heading ?
Because velocity = speed + direction
Are we only utilizing the direction part ?
The tangent is the velocity yes
Yea
Atleast the direction of the velocity
I can't remember if that equation gives the correct magnitude

For what? I can ask my mother
Is the length of the tangent vector the speed?
Lemme ask
Of the velocity vector yes
Good question btw
I don’t think it’s the full speed
I think it would be a constant speed of 1
Wait the tangent vector on it down without normalizing it?
Yes it’s the speed
Magnitude of velocity = speed
Speed is a scalar
Yes but I can't remember if that equation gives the tangent vector of the same length as the velocity vector
is the tangent velocity
The tangential velocity is usually the length of the tangent vector
Why do I feel so smart

Lol
.
@midnight haven do you think you can ask her this
Will ask
Starting from here
Choose one paragraph
Wait lemme ask it here again for better understanding
Yes pls
Unit tangent vector: tells us how a particle moves as far as it’s direction
(How its direction is changing)
Unit tangent vectors come from velocity/ magnitude of that velocity
But what we also know about velocity is that it’s a speed + magnitude (speed going a certain direction)
Do we care about this information when considering how a particle changes direction ? Do we utilize this information about what a velocity is in relation to how a particle changes directions? Since that’s our main goal
Alr lemme ask
Thanks a lot
We care about the velocity to find the direction but we intentionally strip away the speed
Ohhh
That’s why we take its magnitude?
Oki
If that’s fine with her
She said yes
Alright so when it comes to the unit normal vector: this tells us how a particle is turning
Now what does turn here mean?
And when it comes to that turning , why do we obtain that turning information through taking the derivative of the unit tangent vector and dividing it by its magnitude ?
I'mma ask
In the world of calculus, "turning" has a very specific geometric meaning. It isn’t about how fast you are spinning your wheels; it’s about how much the direction of your travel is deviating from a straight line...... ( basically means it doesn't means that it not abt how fast u go if uk then uk)
She said basically
the dividing by the magnitude isn't relevent to the turning information.
Am just explaining for fun ngl
it describes turning in the same way the second derivative describes turning of a function
When we talk about a particle deviating from a straight line what’s that supposed to mean on a space curve (I’m using the definition of what turning means that was provided)
If the particle continued on a straight line without turning then it would have constant tangent vector (direction)
On a space curve, a straight line is the path the particle would take if it stopped turning and just kept its current heading forever. This is the tangent line.
I should have said that Instead of this
Ohhh so basically we can say that the turning is the path that “curves”the particle along the curve
Right
You can imagine that the normal vector is applying a force
Okay, now why does T’(t)/|T’(t)| give us that information about turning?
As T is the first derivative, that equation means the normal is the second derivative
the devision is just making the length one to make future maths more convenient
To understand why \frac{\mathbf{T}'(t)}{|\mathbf{T}'(t)|} captures the "turning" information, we have to look at what the derivative of a direction ACTUALLY REPRESENT SSSSSSSSSSSSSSSSSSSSSSSSASSSSSSSSSS
I’m gonna put this in latex
I think it is but you missed the $$
$$To understand why \frac{\mathbf{T}'(t)}{|\mathbf{T}'(t)|} captures the "turning" information, we have to look at what the derivative of a direction$$
warbeast002
$\frac{\mathbf{T}'(t)}{|\mathbf{T}'(t)|$
Oops
bro
To understand why $$\frac{\mathbf{T}'(t)}{|\mathbf{T}'(t)|}$$ captures the "turning" information, we have to look at what the derivative of a direction
warbeast002
Lol
I don’t think I understand this properly
Consider the standard derivatives, position derives to velocity and then to accelleration
Im sure you can intuit why accelleration would be a 'turning' value
She said and I quote think of it as a car steering wheel
Okay
Lol
We wanna take the derivative of velocity is that what she means ?
I mean that’s the thing I don’t understand why the derivative of velocity gives us insight on Turning
NOOOO
the derivative of velocity is accelleration
Wait no no
Derivative of the unit tangent vector
Divided by its magnitude
Which is the formula for the unit normal vector
Where are you getting unit tangent vector
Yes
Formula
Its not a unit vector though
But why does that give us information on turning to begin with
It is
The tangent wont have length one
T(t) is a unit tangent vector no?
A 'unit' vector is one with length one
Which the tangent vector doesnt (probably)
Bro idek anymore bro it was me giving all the ans from the begging my mom left since last week
that isn't what the equation shows
Bro WHAT
Wait actually ?
They call me 𝕡𝕣𝕖𝕞𝕚𝕦𝕞 for a reason
Is your mom also not a teacher
No it was just me using my brain cells
AY WHAT U MEAN
Who else was gonna answer if it was you other than you
Thanks
Bruh
Why do we use that formula
The one for unit normal vector
Ok lemme look in mi books
Why not ask ur mum 🤔
Cant u not read
Well I can still ask bc she may not be a teacher but she is very good in maths
But for the rest of the question s I was answering for myself
Idk man ur mum seemed to be giving pretty good answers 👍
He’s trolling
Who
\mathbf{N}(t) = \frac{\mathbf{T}'(t)}{|\mathbf{T}'(t)|}= the formula for de unit nrml vector or V
$ \mathbf{N}(t) = \frac{\mathbf{T}'(t)}{|\mathbf{T}'(t)|} $ = the formula for de unit nrml vector or V
Bro
oma god the bot hates me
Lol
$$\mathbf{N}(t) = \frac{\mathbf{T}'(t)}{|\mathbf{T}'(t)|}$$ = the formula for de unit nrml vector or V
WeAreIngram
Bro what is happening
Me
