#help-27
1 messages · Page 307 of 1
Is it a place holder or smth?
what's the derivative of x^2?
YES
For?
So it just has to satisfy that function?
C can be any number you want it to, and the equation is still correct
😭 huh?
Calculus confusing 😭
recall that the derivative of f(x) is the rate of change of f(x). the rate of change does not change whatsoever where f(x) is located vertically on the graph, which is the same as adding an arbitrary variable C to the function, so x^2 and x^2 + 1 and x^2 + 69 all have the same derivative, i.e. 2x
it's really not 😭
I need to learn algebra 1-3 and geometry still
differentiating a function yields you a function, but it's not an injective operation. there are, again, infinite functions whose derivative is the same
that is, (x^2 + C)' = 2x for all C
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can you find the derivative of
x²?
x² + 1?
x² + 100?
they are all the same.. so if you have d/dx x² + c, then the value of c doesn't matter
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✅
the owner deleted the og message
😮
and?
ok fine
!show
Show your work, and if possible, explain where you are stuck.
He accidentally made the post
i’m fucking with him
lmao
😂
Dont count me out
i don't know how bro is gonna do with differential equations
,w plot x^3 + 1
,w plot x^3
the slope/rate of change is the same at each point it’s just that the graphs differ by a vertical shift
so if you’re given a function f that you’re integrating, you’re finding a function with a derivative of f but since you can shift a function without changing its derivative we add the arbitrary constant C to account for this
if however you’re given some "initial condition" you can then substitute in for x and y to find what C must be
for example, if we had f’(x) = 2x and an initial condition of f(0) = 69
Marshall The Gamer
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we know from integrating f’ that we get f(x) = x^2 + c
but since we have the condition that f(0) = 69 we then have 69 = (0)^2 + c hence c = 69
if you want to type infinity it’s \infty
no, the left hand side is an indefinite integral wrt x which means its a function of x, whereas the right hand side is a definite integral with bounds, so the answer is a number (in terms of n)
yep
What about -infinity to infinity?
,w int_{-infinity}^{infinity} e^(-x^2)
that's still a definite integral so still a number
😭 i should stick with algebra 1-3 and geometry then precal
what’s algebra 3
Is there no algebra 3?
not where i live
Oops
algebra 1 —> geo —> algebra 2 —> precalc —> calc
Ok yeah, that
if you like this stuff you should go get some books and learn on your own
for the fundamentals
I just spent $70 on coding books so i am broke boi
im still so confused by the american math education system why are the levels of education named after subtopics of math
And it was right as i went from coding to math too
tough
😂
what else should it be
just call it math?
My grandma should be able to, grandmas are always rich
if you need names for each level
Too basic
are you european
Kneif friend me back
you said algebra 1 -> geo -> algebra 2
does that mean there's a period of time in which you learn algebra, and then you learn geometry, and then you learn algebra again?
you didn’t add me
It says pending
algebra 1 is like basic inequalities, lines, quadratics, factoring etc
systems of equations
maybe some completing the square
Yeah, i think i already got that, so i need geometry and algebra 2
wont take too long
yes ? you cant learn everything at once
i accepted it
Yippy
Says who 😤
I’m 13 and “attempting” to understand calculus
Because i really dont
😭
wait is each one of these courses like "algebra 2" or whatever a whole year
you haven’t learned the fundamentals
My science teacher said algebra more fun
yes lmao
it’s dumb
because why can't you just do multiple topics in one year and just have it be math and like
ordered by difficulty
I am trying to take it over summer
Slower for less gifted peeps
because american high school education is terrible and teaches to the worst students
who get left behind in elementary school
and never catch up
💀
you have to go through the intermediate stages first, you really shouldn't just skip to calculus
dont push it, you will get there in due time
I was bored and thought calculus would be fun, i am planning on learning intermediate before i start really looking into it
What does
Marshall The Gamer
Do?
its two integrals, one inside another
it’s used in multivariable contexts
knief
Oh
knief
$\iiiint$
Marshall The Gamer
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I broke it
if you really want to understand calculus, start at sequences, series and limits, knowing what a double integral symbol is won't be useful to you until later
this is a good playlist
Ik
man I skipped my entire sequence chapter in my precalc class and got away with it in final exams, i hope i wont run into any issues in calc 1
💀
you won’t
👍
calculus 1 seems easier than precalc
I love sigmas
at least the limits look easy
$\sum$
Marshall The Gamer
the hell is that symbol
I am Σ
summation
do yall use it in calc
yep
i think i skipped that shit too
you’ll see it in riemann sums
A sum of a series increasing in value by set intervals
please dont skip this stuff lol it will be important
I am so Σ
you dont want to encounter it at a point when your teachers or professors bring it up and assume you already know what it means
I wrote a formula with it, took me an hour but it works
👍
my initial plan was to major in computer science, then I decided to switch to computer engineering
i skipped my entire discrete math class too
i hope i wont run into any issues in comp eng classes
discrete math is the worst bs i ever seen
Good luck 💀
nope
I’ve tested it
your notation is wrong
Wdym
k is the index
Can you adjust my variables?
the first summation also has no lower bound given
slap a couple variables there it should fix it 👍
yep
You set the lower boundry, the first one is the input
you have to write that?
It is a formula for solving summations where K ≠ 1
I have tested with a summation calculator and it evaluates properly
K-1 is just saying that the N value for the summation is equal to K-1
that is definitely not how the notation works
It is just representing a variable
It holds no value on it’s own
if you’re trying to represent some other quantity then you can’t use k since it’s the index variable
So how would I represent that the N in the third summation is equivalent to the lower bound of the original summation - 1?
the original summation doesnt have a lower bound 😭
You set the lower bound yourself, plug in the values
$\sum_{k=1}^n k$
knief
The rest of it is just a way to solve for it
sorry
lmao
again, that's not how the notation works, you can't just leave part of an equation blank to fill in, use a variable instead
💀
So it would be K = g or smth
yes
do you want two nested summations? like $\sum_{k=1}^n\sum_{j=1}^{k+1}x$
DiamondPanda16
it doesnt seem that way since all the summations are isolated in parentheses
and i dont think he's at the point where he can apply nested summations yet
Like this?
I cant
why N = Z?
A placeholder variable
$\sum_{k=1}^n k = 1 + 2 + 3 + \dots + (n-1) + n$
knief
Ik
what use is there in saying n = z
Z is the input variable
no
Its just saying that you set the value of Z and the upper limit of the summation is equal to that
just leave it as N then if you want it to be a variable
the notation on the upper bound doesn't work that way either;
in this kind of summation, both the top and bottom should have a value that represents the lowest value and highest value of the index k; and the notation k=1 on the lowest bound is only using the equality sign to indicate that k is the index of that summation
Whats an index?
I haven’t learned it yet
the value inside the summation that changes in each term of the sum. here it's k
Ohhh
if you want to understand summation notation, you should start again and maybe watch some youtube videos that properly explain it
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its correct now
I know how summation works
Index variables hurt my brain
it feels like you're trying to skip ahead and get to more complex topics without having fully done the learning and practice required to fully understand the concepts that surround them
I spent a good chunk of time focusing on summation, so i understand the general concept, i cant calculate large summations by hands though as i do not know the proper way to convert sigma notation into algebraic notation
the sums you're working with are called arithmetic series and have a closed form that doesn't involve any summations, but you do have to understand that summations can be very general and the expressions inside of them can be arbitrarily complex, which is the thing that makes them so useful in the first place
have you seen that $\frac{n\cdot(n+1)}2=\sum_{k=1}^n k$
lava
Yeah, that formula is actually what led me to finding sigma notation
if you wanted to move on from here, you could search up something like the geometric series
Would khan academy be a good source?
idk anything about khan academy but theyre probably reliable
I need textbooks 😭
you could wait until your school curriculum covers this material, lol
summation is covered before 12th grade
So prob 2-3 years
at least it should be
if you think you should be in a higher level math course why don't you propose it to your teacher
I dont want to skip grades, and i am already in the honors program
I have to wait until high school to be able to take way higher level classes
Lava I sent you a friend request
then what's the hurry
I get bored, and i love math
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Can someone help understand how to do restrictions?
For example,
with the square root function, everything inside the square root has to evaluate to a number that's not negative, right?
the restriction on a square root is that the value inside should always be at least 0
so you can say $18x^4y\geq0$
lava
the restrictions on the individual variables are the inequalities that you can choose so that this restriction will always be true
i think you can just leave it in this form for this question
I don’t get it
well you can't take the square root of a negative number, therefore the number inside any square root has to be at least 0
yes
And how about
Figuring it out
Fixing out if the number that has to equal to 0 or higher
Figuring*
in this problem the expression is $3\sqrt{18x^4y}$, and the number inside the square root is $18x^4y$. So you know that there must be the following restriction: $18x^4y\geq0$. You can simplify this by dividing both sides by 18: $x^4y\geq0$. And because $x^4\geq0$ for all values of $x$, the restriction on the variables must be that $x=0$ (so that the whole expression is equal to zero), or $y\geq0$ (when x is nonzero, you can divide both sides of the equation by $x^4$ to find this)
lava
sure
i see
Wait I think I understand it now
instead of using an inequality, your teacher finds the point where it equals zero, and tests each side to determine whether that side causes the inside of the square root to be negative or positive
The result is the same though
Yeah he uses 2 cases to show and prove that anything lower is incorrect
So when stating a restriction
Do I state the answer of what X equals?
well you have to figure out when the inside of the square root is equal to zero, and then you have to figure out whether to use a less than or greater than sign, etc, by your teacher's method
Hm
I’m not sure if the case proving is necessary I’ll have to ask him
Finally I figured it out though I was just missing a little bit of information
Thanks lava
no problem
But how would you say
Find a restriction for a question with no variable
For example
Square root of 108
i mean there's not really a restriction
there's no restriction if there's no variable
108 > 0 is always true
the restriction is on the values the variable can take
its either just true or not true
Hm okay
if you were asked a question like that, with no variables, you could either say "there is no restriction" whenever it's a positive number inside the square root, or "DNE (does not exist)" whenever it's a negative number inside the square root
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Where am I going wrong? I'm trying to do 675 / 15
You divide the 675 by the 5
And then the 3
Then u have ur answer
Yes?
Or should it be 3, and then 5?
@mortal pendant Has your question been resolved?
(you should probably cover up your name) the division of 5 is correct, im not quite sure what you did on your division of 3?
also yes you can do that, either doing 3 and 5 or 5 then 3 both works and would yield the same result
3 goes onto 135, 1, 0 times, remainder 3, and 3 goes into 33 11 times
And 3 goes into 5
0 times
Wel
Once
And so on
What went wrong here?
@proper kindle
@solid osprey
it should be remainder 1 no?
Which?
3 goes to 1 0 times, so remainder 1
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help
The sequence of natural numbers x,y,z forms a geometric progression whose denominator is a natural number. Find the terms of this progression if it is known that their arithmetic mean is equal to (y+9)
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What have you tried?
@celest grove Has your question been resolved?
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Is this proof correct?
i'm assuming it's rough since you're on an ipad and not paper/pencil, but you should make sure your handwriting is legible. There are some spots that are particularly difficult to read, such as isin P and the boxed section up top
instead of that purple bit up top, just put "therefore ac > bc" at the end
Yeah, I'm also hallucinating a bit. I see $i\sin$ rather than just is in.
;(
Apologies my hand writing is pretty bad sometimes
I can re write neater if you can’t read it
@calm heron Has your question been resolved?
Do I have to do the since c is not in p and c not equal to 0 or is there shorter way
(It’s my first time attempting formal proofs)
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Hiii
How would I draw the contour lines for z=2x^2 for 2<=z<=8
I was thinking it would be a parabolic shape but i don’t think this is right
x = ±sqrt(z/2) is what you get as your contour line equations
@tacit crow Has your question been resolved?
So will it just be straight lines?
yup
Vertical lines
yup
Oh okay great thanks
I don’t really understand the contour lines. Because now I’ve drawn them and if I have z=8 for example then x=+-2 but then on the z-x graph, z isn’t 8 but z is all the values if you know what i mean?
@tacit crow Has your question been resolved?
the contour lines live in the xy plane
the contour lines show you where exactly z is 2, 3, ..., 8 looking from the top
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derivative of a composite solved using chain rule and quotient/product rules. 💀 im foiling out the highlighted part and i don't think that's what im supposed to be doing. please help 🙏
there is no x^2 term in foiling
two x^3 terms are what you should get
x^2 * x and x^3 * x^0
im confused
OHHHHH
so the correct answer would be h'(x) = 45x^5 + 84x^3 + 25x / √x^2+2 ?
ok i ended up just putting the answer in to check... now im confused how i got 84 and they got 90...
<@&286206848099549185>
i did that part, 3x^2^2 + 1^2 = 9x^4 + 1
and then the x on the outside made it 9x^5 + x
nope, it's wrong
you're acting like (a+b)^2 = a^2 + b^2
someone doesn't remember their quadratic identities...
if you don't remember
oh my goodness gracious
write (a+b)^2 = (a+b)(a+b)
and expand
either .close or .solved
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If f is a function that is differentiable two times on a point a, then I can conclude f is differentiable once on an open neighbourhood of the point a correct ?
I don't think this is true
I think you can compress a sawtooth function so that all its derivatives at 0 are 0 but it has cusps infinitely close to 0
Yes maybe if given that f is differnetiable on 0 once but you can't if it's differnetiable twice (?)
Because then $f''(x)= \lim_{x \to 0} \frac{f'(x)-f'(0)}{x-0}$ exists, and therefore (i have no idea why) it means it's differentiable once on an open neighbourhood of 0
I'm trying to figure out why
prograce
Idk might be wrong tbh.... if you,could write the counterexample I would appreciate it
If every neighborhood of 0 had a point of non differentiability, then this limit wouldn't exist.
Because it would always have points that are undefined no matter how close you go to 0.
Do you epsilon delta?
Yes?
I see makes sense so there has to be a neighborhood where it's differentiable in all points in the neighborhood
There is more than one way to define second differentiability at a point though
If you want it to be the derivative of the derivative, then yes the derivative must exist in a neighborhood. But that isn't necessary for finding the second derivative at a point.
So the theorem is true?
Ok well, I don't want that information to find the second derivative at a point I want it to use that it's differentiable at open neighborhood of a
Differentiable two times at a point is ambiguous though
Why? Isn't it straightforward?
Differentiable twice at point x => f"(x) exists
What else can you conclude from differentiable two times ?
You can define it as f(x)= f(0)+ ax+bx^2+o(x^2) existing
Ohh
Could be, but usually in my course this is the default
This could be useful for another question
If there's context that says the limit of the limit must exist, then I think you're good because a limit can't exist at a point which is an accumulation point of holes of the domain
Yes
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I cant figure out how to do this
break into cases according to the size of group C (it can have either 1, 2 or 3 students but no other number)
@toxic spire Has your question been resolved?
Hmm
What about the cases of group A and B having no students?
well you will have to subtract those away in each case
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this is the graph of the first derivative
does the function reach local extremum
the answer says No but I thought Yes becuae there are places where f`(x) = 0
but the second derivative is 0 here as well so these are inflection point not extremas yes?
sbd plz help
I think that there can be an inflection point at the same time with an extrema so i dont knwo
I am stupid, there cant be an extrema and inflection point at once
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this is like my 6th time asking for help today
♱
How do i find the inverse function of this
am i supposed to polynomial division
i lit dont know where to start
try to solve for y
i tried doing the graph of 1/x but that did NOT help
Sure. Or note that $\frac{2x-1}{x+3}=2+\frac{A}{x-3}$.
;(
right.......... Howd u get there
factor 2 then you got x-1/2 then add and subtract 3
You can always just note that the the coefficients of the x should match up.
Plus?
acciden
Oh, nevermind, I can’t see well cause of the glare.
Ok wait but how do i find the inverse function now
y - 2 = -7/x + 3
?
$y-2=-\frac{7}{x+3}$
♱
guys literally what how r u supposed to find the inverse of fractional functions
multiply by x+3
♱
hmm
It doesnt make sense why is the inverse just shifted vertically
i have no idea
-7+6 = -1
$\left(y-2\right)\left(x+3\right)=-7$
♱
$xy+3y-2x-6=-7$
♱
$y\left(x+3\right)=2x-1$
♱
U just get back at the original position
chatgpt says the inverse is (-3x - 1) / (x - 2) but i dont trust it
!nogpt
Please do not trust ChatGPT or similar AI tools for mathematical tasks, as they often generate output which "sounds correct" but has numerous factual or logical errors. Use of these AI tools to answer other people's help questions is strictly against server rules (see #rules).
no
i lit don't get it
the next question is another "find the inverse of this fractional function"
how can u . When if u multiply u get xy terms
in class we did a method that was like
Polynomial divisiona
and then doing something with the gra[h of 1/x
I don't get that either
I know what happened and it was misleading
should have worked with that smh
what did u mean try to solve for y
x(y+3) = 2y-1
xy+3x = 2y-1
xy-2y = -1-3x
y(x-2) = -(1+3x)
y = -(1+3x)/(x-2)
When you have an equation y = f(x) and you want to compute the inverse
then first step is to flip x with y
x = f(y)
and then solve the equation for y
ok i got this
Oh
Ok the graph is shifted when its inversed bc
The asymptote at -3 just becomes an asymptote at 3
idk
I think
the inverse function of a function is basically symmetric to y = x
yeah i js did that
so i think
also
for
I am guessing it works for this too
our maths teacher also said to
try to find the inverse by restricting the domain/codomain?
But idk how that would work
i mean, i know how it would work for functions like x^2
but no idea for this
alr
whatev
I did it
I'm done w the hw and everything
so ty again for helping
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.here you don't have to actually
Can someone explain why this ain’t the right anwser
For reference this is the right answer, but idk how they get 484 in the square root
Also ignore I didn’t square root the 484 on the bottom in the image I initially sent, I noticed that and forgot to change it bc it in pen rn
remember $\frac{x^2}{484} + 1 \neq \frac{x^2 + 1}{484}$
BuilderDolphin
yep
I have to find the like demoninator
Bruhhhh
I’m such a goofy
Thank you so much
I was worried I was wrong again😂
Have a great one, you’re amazing!
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how come this is 1
i am getting lim x-> inf of sin(1/x) which is 0 divided by lim x-> inf of 1/x which is also 0
so 0/0 = undefined
taylor expansion
A relatively straight forward proof is to use the substitution x = 1/u and use the definition of the derivative
or I guess it's clearer to use the substitution x = 1/h
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Hi I'm not sure how to set up this hw problem, what steps would you guys use to tackle this?
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did i do this correctly? my answer is 104.142
what is your work exactly
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what do you mean
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seems good to me
by the say, x^2, x^3, x, 1 and x^3, x^2, x, 1 are the same bases right?
does order matter?
yes, order matters
it matters a lot
if you take the basis {x^2, x^3, x, 1} of V instead, then D(v_1) = 2x = 0 * 3x^2 + 1 * 2x + 0 * 1
so the first column of the matrix rep of D is [0, 1, 0]
not [1, 0, 0] anymore
that's why axler defines bases to be lists rather than sets
i see, thank you
btw, what does differentiation matrix look like for nonpolynomials?
well you have to have some subspace which is closed under differentiation to have a matrix representation
the vector space of differentiable functions has uncountable dimension, iirc
so matrix rep doesn't quite work
actually, it might be countable, idr
e.g. the subspace $\vspan{\sin x, \cos x}$ would have matrix [ \mat{0 & 1 \ -1 & 0} ]
cloud
but either way, matrix representations of linear maps on infinite dim spaces aren't isn't quite the same
but as cloud says, a f.d. subspace would be fine
a very niche integration technique is to invert the differentiation matrix for a particular subspace
is there such a thing as infinite matrix?
if axler defined the matrix using basis, how would it make sense in infdim space?
i think you can do something with countable bases, but you run into hairy convergence issues
your bases become sequences in infinite dim, and I'm pretty sure you need to force said sequences to have only finitely many non zero elements
or else you do indeed run into convergence issues
for matrices, the consequence is that each column of an infinite matrix must have only finitely many nonzero entries
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does anyone have an explanation or video or something as to why if the discriminant of a straight line and a quadratic equation being equal to zero proves that they are tangential? I get the concept and can apply it but it doesnt make 100% make sense in my head.
example Q:
prove that for all real values of m, the line x=(y/m)+m is tangential to the parabola x^(2)=4y
working:
y=(x^(2))/4
y=mx-m^(2)
(x^(2))/4=mx-m^(2)
m^(2)-m^(2)=0
therefore Δ=0, and so the lines are tangential
I understand how to do this question, but I cant fully visualise how the discriminant of both lines combines being zero proves their tangentiality
@dire mica Has your question been resolved?
Do u understand what we did here? Like why did we equate the two?
@dire mica Has your question been resolved?
if you equate a linear and a quadratic equation, that gives you a new quadratic equation whose solutions are the intersection of the line and parabola
there are 3 possibilities there:
- they intersect twice, so the equation has two solutions, so discriminant > 0
- they intersect once, meaning they are tangent, so the equation has one solution, so discriminant = 0
- they don't intersect, meaning the equation has no solutions, so discriminant < 0
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Question: You are asked to arrange 10 books titled A through J in an ordered list such that the following pairs of books are not beside each other: (A, F), (B,D), and (A, B). In how many ways can the books be ordered. Provide reasoning.
My Attempt:
Total number of ways: 10!
Number of ways (A&F) or (B&D) or (A&B) occurring with everything else being random: 3x(2x9!)
ways A&F and B&D are adjacent: 2x2x8!
ways A&F and A&B are adjacent (Only happens if FAB or BAF): 2x7!
ways B&D and A&B are adjacent (Only happens if ABD or BDA): 2x7!
Ways all 3 pairs are adjacent to each other (Only happens if DBAF or FABD): 2x6!
Where I'm stuck: Not even sure if the last three lines are correct. Can't wrap my mind around the correct way to compute the overlapping. Thank you!
@restive river Has your question been resolved?
no
@restive river Has your question been resolved?
@restive river Has your question been resolved?
if u think abt it
the only way A,F and A,B and B,D
are arranged together
is with some permtutaion
of araning these groups
so do not consider sperete cases
Well it says that the pairs are next to each other, so the case where AFBCDEGHIJ is wrong as well as a case where two of the pairs are next to each other, or even all 3 of the pairs.
The question is not asking about only the case where all 3 are beside each other. From my understanding we need to consider separate cases
@restive river Has your question been resolved?
how about you stop trolling?
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!status
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
@cerulean badge
your notation is a little bit all over the place
and it's hard to work with or think about or even read
(your handwriting also doesn't really help)
but there is a clever way to do this
😭😭😭I'm sorry
just to set your notation straight a bit: let's write $a_n$ for the $n$'th term of the GP. (notice that the ``th'' is not written)
ann.in.a.teacup
we have two sums: $A := a_1 + a_2 + \dots + a_n$ and $B := a_{n+1} + a_{n+2} + \dots + a_{2n}$
ann.in.a.teacup
our goal is to show $\frac{A}{B} = \frac{1}{r^n}$ yes?
ann.in.a.teacup
(i have not made any calculations so far just writing what we've got in a clean way)
Okay 👌
ok now
the trick is you do not actually need to calculate either A or B themselves
you could but it would take a lot of work
(maybe not so much that i would say "it would take you 17 years to do that" but still)
the trick is: $a_{n+k} = a_k \cdot r^n$ for any index $k$.
ann.in.a.teacup
do you understand why this is?
Nope, never seen this actually 🤔
well ok you know what a GP is in general right?
Yeah
going from one term to the next means multiplication by r
Yes
$a_{n+k}$ is where you get when you take $n$ steps like that starting from $a_k$
ann.in.a.teacup
Yeah
ann.in.a.teacup
Ohhh okay
do you see how to continue?
Hmm kinda, give me a sec
Ohhh
Yeah
It all just cancels out
Nice and smooth
Omg thank you, life saver 🙏🙏🙏🙏🙏
.close
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is my work right
this is the question
i dont have the answer so thats why im asking
,w d/dx sin(x)/cos(2x)
,w sec(pi/3)(cos(pi/6) + 2sin(pi/6)tan(pi/3))
your slope seems to be wrong
oh
yep i forgot the negative sign in the second line after seting the deriv = pi/6
ok so i've got y = 3root3x - root3 x pi/2 + 1
$3\sqrt3x - \sqrt3\frac\pi2 + 1$
gamer75431
is this right
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i dont get it
hello
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oh sorry
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when im comparing coefficients here, as in cos(x), i also have to account for the sin(x)
what would the comparision be? i would have said C1 + C1*sin(x) = 2
but do you have to accuont for the cos^2(x) as well?
woops this is what i meant
anyone?
Can't do comparison here
yes you can
I can help you
please do
what?
??
@solemn marten Has your question been resolved?
anyone
thgis was incorrect
can someone other than an ai help me
what can I heip you
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just do one after one
the cube has a diameter of 8
cubes dont have a diameter
so i thought the raduis of the sphere is 4
i mean the diagonal line
likea like equal to the side length
the diagonal of that cube is not 8 either. The edge is 8
the edges ?
i mean any line equal to the edge inside the sphere
that's different. The diameter of the sphere is equal to the cube edge
which means that this is correct. But careful with naming stuff
now, what's the volume of a sphere or radius 4?
tbh i do not know anything abt cubes execept their volume
anyways so 4/3 x 4^3 x pi
which is...?
D and C
what about B?
you can add another one
they are basically asking: with same center, can you have sphere A? and sphere B? and sphere C? and sphere D?
its not particularly well worded tbh
that doesn't look like a tangent point to me 
is this correct
this
so I know that to find the average
we use slope formula
so i choose the points T, F2 and T+3 , 0
however, it did not work with me
that should give F2 / 3
that's not wrong, but it's not one of the options so you have to choose different points
let me try again
answer is F1/T+3
which points u used
Do you want to explain the solution process?
you can get that with (0,F1) and (T+3,0)
first 𝑇 hours is F1-F2,
The remaining fuel 𝐹2 is used up in 3 hours, so the fuel consumption rate during these 3 hours is F2/3
negative sign is ok, you'll also get a negative sign with the other points you tried
oh right because its decreasing
yes
if you have constant velocity of 0 then you're not moving
if you have constant velocity of say, 10 km/h then you are moving
At 𝑡=0 both autos start together.
If A has a positive velocity and B has a decreasing velocity reaching zero, then A moves ahead while B slows down.
If B's velocity becomes negative, it moves in the opposite direction.
If B's velocity just decreases but stays positive, A moves faster, and they still separate.
yeah imagine 2 cars driving next to each other, and one of them starts braking
So, A and B move apart, making Statement I correct.
@feral bobcat do you understand?
but negative veloctiy just means its speeding down right?
no that's negative acceleration
negative velocity means driving in the opposite direction
dang that is kinda counter intuitive
yeah Axe is right
but here its positive velocty?
you don't really need to think about negative velocity for this problem
yes
Distance traveled is found by calculating the area under the velocity-time graph.
Since A has a constant higher velocity, the area (distance) covered by A is larger than that of B, whose velocity is decreasing.
Hence, A travels a greater distance than B, making Statement II correct.
ok so let me just recap
while velocity is in the +y axis, this means it is moving right ( the same direction of A in this same)
when it is -y axis, it is moving the opposite direction, and the decreasing line just shows the magnitude
the distance traveled by A is the area of triangle A and in case of B is the area of square B, so imagine.
Um...
so both are right
is this correct

yeah both is right
v = displacement / t
then this means I is wrong
never
yes, you are wrong
v * t = displacement/t * t
dude why is this confusing 😭
what about you, @feral bobcat ?
easy boy, take it easy.
v * t = displacement/t * t , do you agree?
???
what are you doing now?
Hey
am here
i am just trying to analyze how I is correct
if they both are moving forward
how does that mean they are moving away from each other
we could say that A is moving faster or farthe
Do you know Einstein's theory of relativity?
bro how is that related
@alpine python
is this correct
they are both moving right
so how does that mean they are moving away from each other
NO you are Wrong
they are both moving forward but their separation is increasing
so does that mean they are moving away from each other?
i feel the wording is trash for that question
eh
that means they are farther from each other
Hey
if A moves faster than B, B looks A is away from own
Yes this Johmsmith0317 is right
ok ig i over thought
good
Great
anymore?
of course
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hello
