#help-10
1 messages · Page 267 of 1
Oh that suppose to be a 3
there shouldnt be a sqrt2 under it anyway, the dot is multiplication
but this ^
just riddle me this
?
You said the dot is multiplying
im referring to the one after 13 root2
2
and what is 2^3
8
so what is (sqrt(2)^2)^3 * sqrt(2)
8 root 2
5 root 2
Thank you
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Need help pls
Ok so you know derivatives??
Nope
Ok no problem
do you know the formula for the vertex of a parabola?
Oo that
So you are working examples on completing squares ?
What did you get after completing squares
Not sure
Do you know how to complete square
No
Wdym =5
Sry s
Wait follow me
Alright
Then look at 80t-5t²
Now 80t should be in the form of 2ab if you compare it with the one above
Okay
16
No
..
You are taking -5 common factor from 80t-5t²
O
So 80t-5t²=-5(...)
What should be in place of ...
Correct
So -5(t²-16t)
Now compare the inside of the paranthesese with a²-2ab+b²
You will notice that a=??
T
Correct
Ohkk
And 2ab=?
16
It is 16t in fact
Oohk
Not sure
Then why did you say 8
Look nvm
K
So 2ab=16t did you understand why
Yh
We have a²-2ab+b² we know that a² is t² we want to which of the other 2 refers to 16t
Since b² doesn't contain a in it then it doesn't have t
But 2ab on the other hand has a
So it has t
at
8
Great
Now
Now what we want is to reach a form c(t-d)²+h
That's why we were talking about (a-b)²=a²-2ab+b²
-5(t-8)
No
O nvm
Wait dont be in a rush
Ok
(T-8)^2 = t^2-16t+64
Ok nice
We have t²-16t we are still missing +64 to get (t-8)²
To get this number we can simply add and subtract 64
So we are basically adding a version of 0 which doesn't change anything
Hm
Yh
Hm
Yh
A
What's the sign of -5
Ok what's the sign of (t-8)² for any t
Ok
What's the sign of 320
Ok
Now -5(t-8)² is either negative or 0 bc negative multiplied by positive gives negative and negative multiplied by 0 gives 0
Yh
Yh so it's 0
And if -5(t-8)²=0 then -5(t-8)²+320=320
Yh
.
?
Do you know how to solve this equation
Ok what is/are the solution(s)
Correct
Hm
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trying to find the cofunction in radians
i got sin 22.5pi/90 by
3(180)/8 getting 67.5, getting 90-67.5 to get 22.5 for the cofunction
so assuming thats all right trying to figure out a way to simplify sin 22.5pi/90
it twas not right that simplifies into pi/4 of course
so where did i mess up?
lol nvm 90 is supposed to be 180
its right
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hi people can I get some help with this
I graphed the 2 functions, what do I do after that
you know what (f∘g)x means?
ohhh okay
lol
so how do I find f(3)? I don't have the function, I need to make one?
I'm guessing y2-y1/x2-x1 isn't gonna work here
so um f(3) = (3, 1)?
f(3)=1
yeah
yeah
it's that simple?
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Hi guys I am currently learning about application of derivatives and had a question on concavity, so I understand concavity, but to picturize it better I made up a scenario. Here is my idea. Lets say we have a wonky function with numerous turns where the Y axis represents Revenue relative to time. The goal is to sketch the function efficiently. If we had a humongous polynomial function it would be difficult as we would have to input numerous points to get an accurate representation of the graph which is not efficient. However if we take the first derivative and we will get information on the behavior of the function between certain intervals for when the derivative is equal to 0 or DNE. Now we come across a problem although we find the behavior of the function between certain intervals we could argue for each individual sector (interval) that the function can be drawn concave upwards or concave downwards and the behavior would remain the same. To understand whether or not its concave downward or concave upwards we need to take the second derivative which will give us the instantaneous rate of change of Revenue. Now throughout the function there exists a point where we have possible inflection points at f''0 or f'' DNE. Now after the possible inflection points we test points nearby the interval to observe the behavior of the slopes. If f'' > 0 I picturize as instanteous change in revenue being positive, so I think of that as our loss in revenue minimizing and becoming increasingly positive. If f'' < 0 the instataneous change in revenue is negative which means are losses will be increasing. After we conclude the concavity for all the intervals for f'', we can then determine the inflection points.
The importance of inflection points is that if we think about it in terms of revenue we can determine the moment we start making positive revenue and the moment when revenue becomes negative.
I'd like some feedback. Perhaps I could have simplified what I wrote as it does seem a fair bit long, but in essence when we find the behavior of the function for intervals there are 2 arguments we can make, concave up or concave down and we cannot assume as it could be incorrect and we would be changing the data of the function which would lead to incorrect conclusions, this is where the concavity test is vital. I associate f'' > 0 in terms of revenue I picturize that as revenue becoming increasingly positive and f'' < 0 as our revenue dropping, instantaneous change in revenue negative, hence losing.
First thing, polynomials are infinitely differentiable everywhere, so you never encounter a point where its derivative DNE
I should have said functions my bad.
Inflection points don’t determine the sign of the value
I know that.
It tells you when the sign of the rate of change change
So then it doesn’t tell you when you make positive or negative revenue
I know it doesn't tell you, but I was asking myself what is the importance of it asides from the fact that we know its it the transition stage where the f'' sign changes
Sometimes we aren’t too concerned with the places it transitions
and because we know that an inflection point must be continous and have concave upwards and concave downwards before and after the point. So I was questioning how can I apply it.
A big use of the 2nd derivative is telling us if a critical point is a local min or max
Basically what I do is a bit strange at times but I like to apply real world scenarios a lot, cus my goal is to retain the info.
mhmmm.
The sign of its concavity tells us the nature of critical points
I have a question Frost I'd like to ask. I'd like you to tr and prod my analytical thinking to come up wit answer for the DNE.
Basically for the second derivative ik it says inflection point where f'' = 0 or DNE. I'm trying to think abt the DNE aprt and am thinking of a function where when we differentiate it from both left and right the derivatives don't match one another.
I'm just confused on pinpointing an exact function to show this, I can't think of one off the top of my head.
,w graph y^3 = x from -5 to 5
ahhh yes vertical tangent
This function has an inflection point at x = 0
Ooooooh thanks man.
A more readily available example for 2nd derivatives is in physics
i do love physics
This is because the 2nd time derivative of position (given as a function of time) is acceleration
So you get a lot more problems regarding 2nd derivatives
yeah i was thinking of using that scenario to explain concavity which helped.
One way that worked for me tho was thinking abt concavity in terms of revenue wit a wonky function.
what is shm
Frosst
also r u using newtons notation for the derivative?
Simple harmonic motion
No this is more common physics notation for time derivatives
Dots for time derivatives
hmmmmm can I use higher order derivatives using Leibinz's notation?
You can easily inspect that the acceleration is 0 when the object has position = 0
Not familiar with harmonic motion.
You can but physics uses a shorthand for time derivatives as they appear frequently
Gotta learn that unit
so ur analyzing the motion of the spring
hmmmm what comes to mind is sine waves and cos waves.
Not the spring itself
But the actual particle on the spring
Or the end of the spring
so if the particle is oscillating?
Indeed we find that this is a 2nd order ODE with solutions that have sines and cosines
Yes
that is rlly god damn cool.
Simple harmonic motion is things oscillating
so what abt ocean waves or ferris wheels?
Same thing
Well
Ocean waves are more dimensions
The differential equation solution is writing x(t) = ???
This describes the motion
But this gives us explicitly how it moves
I rlly like ur passion man. I too am passionate abt this, but a slow learner.
But I am very hardworking.
Haha yeah this is all very fun and interesting stuff
especially the proofs.
The more you know the more it connect together
The more you understand and struggle on a question is where the true learning occurs.
This even goes into complex numbers in some cases
i needa learn abt complex numbers n stuff.
Right now I am completing calculus 12 and am hoping to do Calc BC, although I think calc 12 comprises of calc ab and calc bc content.
kinda confused tho cus i keep hearing different stuff.
Due to $e^{ix}=\cos(x) + i \sin(x)$
Frosst
i stands for imaginary number right?
never learnt complex numbers before but briefly remember from a video
sqrt-1 = i
You might be able to see how you could get the cos and sin combinations in here
or something like that.
Yeah
gotta learn this.
thanks mate for your time and assistance, just one last query. Yk for the local min and max points?
Yeah what about them
So basically when taking the second derivative I know its useful for pinpointing whether a function is concave up or down, but for maximum and minimum points I remember u said that its especially useful for determining max and min points.
All I have seen so far is that max points are just the critical points where the slope is 0 or DNE, but is there any application
of these local max and min points that I will later find in application of derivatives?
Max points are not necessarily DNE
For continuous functions they are necessarily 0
Or on the boundary then it can have any slope
Well not really
On left side boundaries it’s non positive
On right side boundaries it’s non negative
The point of concavity is that when you find a place where your function has 0 slope
You know it’s a critical point
But you don’t know if it’s a local minimum or maximum
Concavity tells you this
Right.
It tells you via this
And this
Mhmmm.
that makes sense.
but is there any application
in word problems
for these points?
Have you done the classic question about maximising ratio of volume of a cylinder to its surface area?
not yet just a beginner yk what don't reveal spoilers for me ima figure it out.
don't spoil the manga for the anime only
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I need to solve for x so that it makes the quadratic formula. I’m stuck on step 4. I need to complete the square but I think I’m doing it wrong
nope that's right :) what would be that missing chunk?
make sure you add it to both sides of the equation
@quartz lantern Has your question been resolved?
I know I need to square root both sides, but then what happens to the a/bx?
wait nvm
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im stuck, could someone help me finish this? (gaussian elimination)
You need to eliminate this 1 now
yeah, but i just can't find a way to eliminate it
Use the third row
if i subtract the third row, I'll get -1 on the other side, do I just revert it? idk if that would make sense though
Wdym other side?
Yeah this is fine to do
Why isn't it fine to have a -1 there?
isn't it supposed to all be ones?
what is it called again
i forgot the name
the first number after the zeros
You can multiply that line by -1 to fix it
@jade summit Has your question been resolved?
wdym?
You're allowed to multiply a row by a constant
could i also divide by a constant?
Yes!
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how do i do part b
Notice that g(x) and h(x) are constants
yea
so substitute the values in the inequality
how about f(x)
You should have $-8<f(x)\leq7$ now
WhereWolf(ping if needed)
ye
7
No
anything from -8 to 7
0?
We want a range
mhm
Ok let's forget the numbers
Do it graphically
g(x)<f(x)<=h(x) means that f(x) is between g(x) and h(x)
And when is that true
so what would it be
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need some help simplifying this
unsure of how to handle the square on the last term
Well, that should be taken care of, with the coefficient that you have in that ln term.
so it would be -2ln for the last term?
Why -2?
cause i thought i was supposed to do something with the 1/2
Yes, it does.
You will multiply the 1/2 outside the bracket when you simplify.
That'll get rid of 2.
overall cancelling leaving a - right
Yes
then just ln laws?
yeah im writing it out right now
i was just left on my last submision ill get back in a sec
Along the lines of this?
Can I cancel across the fraction like that?
Show the full work. I dunno what you have done with 1/2 ln(x) term but it seems wrong.
ill rewrite it so its more clear
?
do i have to distribute the 1/2 throughout the bracket?
@timid silo Has your question been resolved?
Yes.
Your major error is here:
$$\frac 1 2\left[\ln{(x)} - 2\ln{(x^2 + 3x +2)}\right] \neq \frac 1 2\left[2 \ln{\left(\frac{x}{x^2 + 3x + 2}\right)}\right]$$
Enemagneto
Basically, identity $\ln{(a)} - \ln{(b)} = \ln{\left(\frac a b\right)}$ only works when there are no coefficients(more precisely coefficient is 1) with $\ln{(a)}$ and $\ln{(b)}$.
Enemagneto
ohhhhhhh
Or they must have same coefficients.
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e,f, and g. How do I find the domains if I don't even know what the functions are?
For e i got [-4,3] though i'm not sure if thats right
still not sure what to do for f
g is also ?
<@&286206848099549185>
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which one should I calculate first?
what do you mean by this
inequality
there's one inequality there
is This problem cannot be resolved?
no it can
🥲
i just don't know 'which one' you're talking about
8x-3 or x + 1
,𝐴𝐷𝐶 = 𝐴𝐵𝐶. basically how do I prove b and d
This channel is already occupied
That is a single inequality and there is nothing as such 'which one should I calculate first'. After simplifying both sides simutaneously, you get an interval for x
To start with, multiply BOTH sides by 5
if you're trying to multiply both sides by 5, write it first as $5\Big(\frac{1}{5}(8x-3)\Big) > 5(x+1)$
rafilou2003
then, if you look at what the right hand side gives...
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From this page is Russian: https://en.m.wikipedia.org/wiki/Binomial_theorem Why is the last step in the proof by induction possible?
In elementary algebra, the binomial theorem (or binomial expansion) describes the algebraic expansion of powers of a binomial. According to the theorem, it is possible to expand the polynomial (x + y)n into a sum involving terms of the form axbyc, where the exponents b and c are nonnegative integers with b + c = n, and the coefficient a of each ...
@grave harbor Has your question been resolved?
<@&286206848099549185> Could you briefly explain why the summation can be expanded like in the part of my notes marked with ?
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@grave harbor Has your question been resolved?
nvm so the first two in the sum are re-written a^(n+1-k) and b^k and also there's apparently the rule as above, and that's it
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A car travels from C to E in 6 seconds, how long will it take to travel from E to B (refer to the diagram) note that $EC \neq 6$
SirGareth
What'd do is make |AB| = 1
And then see what ratio of |BE| is of |EC|
And then you should be able to figure something out
what do you mean by those "| |"
Just means distance
SirGareth
yeah that was wrong
just got this. thank you
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okay, firsly, very dumb question
better a dumb question than one not asked at all
ok sooo
firsly
why can't we use the bernoulii
like for example for the P(X = 0), why can't we write it as 3C0 * 0.4^0 * 0.6^3
@royal basin any ideas>
probability isn't independent. Once you choose one tv it's taken out of the population changing the prob the next tv is defective or not
was showering sorry
the sign on the blue oval, is that implies sign guys?
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why isn’t this the same?
I thought x/a/b was the same as x/ab
in the same way that 10/2/2 = 10/4
second equation is supposed to also say x= instead of just x
$\frac{x}{\frac{a}{b}} = x \cdot \frac{b}{a}$
dldh06
ahh so there have to be a set of parantheses
Yes
you can’t just equalize them like with multiplication
No
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so i got these right
but i uh
dont understand why the sets of {A,B} are the same as the OPs of {A,B}
i also uh am not sure about this one
this is right
but im not sure how to count out the fact that the dupes are 2^n
<@&286206848099549185>
<@&286206848099549185>
@amber axle Has your question been resolved?
<@&286206848099549185>
sorry I can't help but also don't just spam the @
i thought its fine to ping every 15 min
which is what ive been doing
if you check the timestamps :P
pretty sure it means if no one responds within 15 minutes you can send out an @ only once
try asking about it in one the channels like proof-and-logic
@amber axle Has your question been resolved?
@amber axle Has your question been resolved?
@amber axle Has your question been resolved?
@amber axle Has your question been resolved?
@amber axle Has your question been resolved?
ordered pair of sets?
you want to know why there are 2^n ways to choose sets A and B, subsets of U, such that A = B? this is the same as just choosing a subset A of U
and there are 2^n subsets of U
if you didn't know that the cardinality of the powerset is 2^n, its because for each element in U, either its in A or its not in A. so for each element there are 2 choices, giving 2^n total possible subsets
ah okay so i can say that:
because the set S of {a,b} where a=b & a,b subset U is just the set S={a} where cardinality of S = # of subsets of U (since a subset U?), and given that there are 2^n subsets of U, then the number of duplicates is 2^n (i get why there are 2^n subsets)
im still confused about this one
im not sure why every OP of (a,b) where $a \in b \in U$ corresponds to every set {a,b} where $(a,b \in U) \land (a \in b \lor b \in a)$
aidanlok
??? why are you doing this in my help channel
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@amber axle Has your question been resolved?
There is a bijection from the set of all ordered pairs (A,B) with A \subseteq B to the set of all sets {A,B} with A \subseteq B; it's defined by (A,B) |-> {A,B}.
Its definitely surjective. If (A, B) and (A', B') are two different ordered pairs that get mapped to the same set {A,B}, then {A, B} = {A', B'}. Thus, either A = A' and B = B' or A = B' and B = A'. We can't have the first case because then (A,B) = (A',B'), contradicting our assumption. But we also can't have the second case--if it were true, then B = A' \subseteq B' = A. This means that A = B = A' = B', so (A,B) = (A,A) = (A', B'), a contradiction as well. Thus, the map is injective, too.
Since there's a bijection, the cardinality of all such ordered pairs equals the cardinality of all such sets
Every ordered pair obviously gives you an unordered pair.
Conversely, every unordered pair has an unique ordering unless $A = B$. In which case $(A, B) = (B, A)$.
Equivalently, even though ${A, B}$ is unordered you can always order it by saying WLOG B is the larger set.
chencking
Hello
okay I kind of get this
kind of
I got my friend to explain surjectives and stuff
I kind of get it
I’ll do some rereading and re read
if the bijection is too scary, chenckings explanation is simpler
the bijection just means for every ordered pair (A,B) there is exactly one unique set {A,B} and vice versa. so theres the same number of the pairs (A,B) as the sets {A,B}
@amber axle Has your question been resolved?
.reopen
@amber axle Has your question been resolved?
wait how do i use you
whats even going on down here
Can I use you?
can someone verify my proof from ToC?
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how can i test this integral for convetgence or divergence using lct or dct?
do i use lnx<=x<= ex?
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ah i see thx and sry
.close

ONLY YOU CAN CLOSE IT BRUH
@amber axle is there still an open question? It's unclear to me.
yeah I know
yep still doing that assignment on at quantifiers
@amber axle the originally posted question?
yes
the original OP -> S(Subsets) question
If we take the answer to Q3.8 as true, then we can consider the cases A <= B and B <= A, with each contributing 3^n by Q3.8.
But you notice that we have double counted the cases where A = B.
And those are 2^n (rather than 3^n) because we can only choose to include in A and B or neither A nor B.
I'm literally just restating the "explanation" section of the question, so I'm not quite sure if this is helpful.
@amber axle if this isn't sufficient, can you explain where this line of thinking loses you?
this is where I don’t get it
I feel really dumb that’s a really simple tuple count
what are we including?
and why can it be in neither??
closed???
No, still open
@amber axle you still here?
yep mb wasnt looking here
No biggie
oh so its 2^n bc for every ele we have 2 choices? in both or missing from both? so, as a hypotheical, if we have ABC instead of AB, in the end, its still 2^n bc its in all or in none?
hmmm ok
the guys above mentioned stuff about bijections
which we're just getting into
but maybe i just leave it as is with ur counting which is good
The bijection stuff isn't wrong or anything, I just thought the counting argument would be more understandable
it is, for what ive learned so far
Ping me when you find it please 🙂

@brazen viper
(posting 4.2 for context, i understand that one fully)
when writing my explanation for 4.3
i was unable to explain precisely why we use the product rule to create the divisior we see in the formula
Sure, let's take the bookkeeper example
Because each e is indistinguishable, we need to divide by the number of ways we could distinguish it, which is 3!
And we also need to divide by the 2! ways to arrange the k, and the o
Because we are dividing by multiple things, this is the same as multiplying them, and dividing just once.
(a/b)/c = a/(bc)
@amber axle
The internal arrangement that is
so because the arrangement of each of the letters is independent we have to multiply their possibilities, but whats the other option? its not like we'd add...(?)
Like, if I labeled the es as e1 e2 e3, and the ks as k1 and k2 whatever order I put the es in, (e2 e1 e3 for example) I can still freely choose the order of the ks
If there was some rule where (for instance) maybe the k1 couldn't go before the e1 then in some configurations we couldn't use all possibilities
@amber axle were there any other lingering doubts?
Well, I think we've addressed everything, so I'm going to try to close this. Just open another help channel if you still have other questions. 🙂
.close
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how exactly would I solve this
the y(0)=1 and y'(0)=0 is confusing me
what would I do
I know the homogenous equation is y''-4y'-12y = 0
im confused on how I would solve it because of this
you mean homogeneous equation
yes sorry
right
then the homogeneous solutions are :
y(x) = A exp(-2x) + B exp(6x)
with A and B some constants
right
where do these come in?
they are just initial conditions bro...
Ok
im supposed to solve it with the initial conditions but dont know how to
its says solve this IVP
they will be useful to find the constants we dont know
initial value problem
in what way?
.
@timid silo before you do that you need to find the particular solution
Ok
the constants are A and B and we will need to find them with the initial conditions
But once you do, you can use the two initial conditions to find A and B explicitly
but we need the particular solution first
take y = Cx exp(6x) and find C 🤔
no, its the homogeneous solution
already found it here
Ok now im working on particular
.
what is t tho
t is x
ok
im trying to solve the particular solution
yea but it doesnt mean you should always take A x exp(x)
nice try
you have exp(6x) in your equation
right
6 is a root of the characteristic equation of our diff equation
.
?
I solved for C
im confused sorry
y'' - 4y' -12y
plug y in this
so it would be the double derivative of exp(6x) -4(derivative of exp(6x) -12(exp(6x))?
double derivative of exp(6x) -4(derivative of exp(6x) -12(exp(6x))
woaw can you write in maths ?
write it in a better way, its hard to read how you wrote it
or take a paper and take a picture of what you did
Ok
eh i dont download files
Herels
bc of this I thought
?
I plugged in C everywhere
remove the 1, 2 and 3
Ok whats next
calculate it my dude
calculate this first
i'll be asleep tho
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i have that velocity is <-6t + a, -4t + b, -4t + c >
and i know that r(0) is (7,8,5) but not really sure where to go from here
and i know that a^2 + b^2 + c^2 = 16, but that doesn't really help much
@steel goblet Has your question been resolved?
<@&286206848099549185>
doesnt the fact that the original position + acceleration = final position imply that like
a= -6w
b= -4w
c=-4w
where w is some number
basically the initial velocity vector must be proportional to the acceleration vector
i have no idea. But i did discover this, idk if its helpful.
So the velocity vector is <-6t +a, -4t + b, -4t + c>
since we know the intial condition for the position, we know that the position vector is
<-3t^2 + at +7, -2t^2 +bt + 8, -2t^2 +ct +5>, right?
yeah
^ i think i found a way to prove this algebraically
I got from line 3 to 4 by taking derivative with respect to time
wait im really confused. I have no idea how you got those equations, and i still don't know how to find a, b, and c
d=Vot+1/2at^2
from the big 5 equations
we start at (7,8,5), then go to (1,4,1)
so the displacement is (-6,-4,-4)
right
and its given to us that the acceleration vector is (-6,-4,-4)
right
but i still don't get how you get that equation
you mean d = Vot+1/2at^2?
yes
okay i understand that
wait no i dont never mind
but am i supposed to be using that formula?
i never learned that in class. And i looked that up and saw that its a formula used in physics but the class im taking is multivariable calc
hm
idk
there might be some other way to solve it
i was kinda approaching it the physics way
i mean i havent taken multivariable calc so..
idk
so im trying to understand this. Is the initial velocity -6, -4, -4?
no
but its proportional to -6,-4,-4
so you use the fact that at t = 0
|V| = 4
so switch -t to w just for simplicity
(-6w)^2+(-4w)^2+(-4w)^2=16
okay. so | <-6w, -4w, -4w> | is 4, right?
yeah
makes sense
wait, how do you know all those w's are the same?
wait do you calculus at all? like integrations?
because -t is a scalar not a vector
from there to there i took derivative with respect to time
but integrating the acceleration vector gives us <-6t +c1, -4t+c2, -4t+c3 > where c1, c2, c3 are all constants that may not be equal
true
but <c1, c2, c3> = Vo
but then how do you find the values of c1,c2, and c3?
so we have this vector equation
but this is really three different equations we can split up
cuz yk if two 3d vectors are equal
all their components have to be equal
random question, but do you know at what time the particle is at point (1,4,1)?
i think its 4/sqrt(68)
because we get that 68w^2=16
so w = +/- 4/sqrt(68)
and we know -t=w
and t has to be positive so t is 4/sqrt(68)
^one way to think about this is it’s basically a taylor series
But because the third derivative is zero we can just write it like that
So it’s really just saying f(x)=f’(0)x+f’’(0) x^2/2!
@steel goblet Has your question been resolved?
dang
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is there an easy way to solve non homogenous ODEs?
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how can I find x
how do i find domain and range and what points do i draw the upside down U
Use trignometry
how though
We have
Base = x
Hypothenuse = x+6
Angle = 67
ngl i went to the wrong channel my bad
Sintheta = perpendicular/hypotenuse
Costheta = base /hypotenuse
Tantheta = perpendicular/base
just regular Cos?
Yeah
Yeah, x/x+6 = cos67
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asking for me to convert to standard form, when it already is?
idk if im missing something
<@&286206848099549185>
hm
thats vertex form
yea
might as well try it
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hi, im trying to find the readius and intervial for this problem, any idea where I may have messed up the limit?
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im stuck on 312
so if i use the chain rule
$sec^2(xy)(y+\frac{dy}{dx})=1\frac{dy}{dx}$
is this right
putridplanet
Right now use algebra to solve for dy/dx
Should be x * dy/dx
right
idk what to do
divide sec^2(xy) ?
$\frac{y+xz}{z}=\frac{1}{sec^2(xy)}$
putridplanet
Distribute the sec first
$sec^2xy sec^2y^2+sec^2x^2 sec^2yx \frac{dy}{dx}$
Wot
i distributed it into (y+x dy/dx)
a^2(b+c) = a^2 * b + a^2 * c
putridplanet
