#help-19
1 messages · Page 115 of 1
Do you see how to do it from here?
Yes, you need to remember how you defined things
yea yea
10/3 x + 120 is the second year
x+270+10/3 x + 120 = total of final
x+10/3x = total of original
total of final = total of original + 390
man
i thought i had something
Total is unnecessary here
You only care about ratio of first year and second years
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im having trouble solving dy/dx x^2-4xy+y^2=4
i tried solving it and i got (2y-x)/(-2x+2y) but apparently thats not right
what did you try
find dy/dx by implicit differentiation
oh
aight bet
i thought you wanted to solve the differential equation 💀
i did
wait for y^2
ye
i thought you just do the same as you would for x but multipy y' to it after
but im assuming thats wrong
do yk the answer
ye
i got (2y-x)/(y-2x)
ye thats right
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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
What did you try?
What is the answer?
Can you see the big triangle is divided by 2 horizontal lines?
Irrelevant right now, the important thing is the process of thinking
Take the smallest triangle in the top, divided by the first horizontal line
And tell me how many triangles can you count
I found the answer but need to be sure before explaining. C(4,2) x C(3,1)
I don’t want to explain how to get the answer, I want him to get the answer himself
Ok
A side note: Watcjing a basic video bout this topic would lead him to answer also
ohh what's the video?
…
Can you do what I asked you?
There is no sense on asking something you don’t want to do
That is the top one
Now
Imagine the first horizontal like does not exist
Only the second
How many triangles afther the second (new first line)?
so find triangles using only the second line?
Yes
7?
How?
oh one sec
Triangle with 2 vertical lines and one horizontal (first triangle of the top)
Repeat the same qith second horizontal line
The answer cannot be different
It is just the same triangle but bigger
oh i see
You repeat this for the third horizontal line (which is the main triangle bottom line)
it should be the same right? assuming theres no first line, and second line
Exactly assuming no intermediate horizontal lines
ok so we got 18
Yes, but you need an intermediate question
If you add the two horizontal lines
The figures inside created by these two lines
Are triangles?
yh it will give us all sort of triangles
The small figures created due to the horizontal lines with the vertical lines are triangles? (Without counting the first small triangles)
i see
But we already know the top is 1+2+3
yh
Where n=2
Number of vertical lines
And 3 is the number of horizontal lines counting the bottom from the main triangles
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hi! did i do this right? i basically just counted (left to right) the distance between D and p which is how i got 3,0
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So like:
Mike wants to invest in a annuity that pays 100$ per month for 4 years (48 months). The annuity has an annual rate of 3.5%, compounded monthly. What is the present value of this annuity?
@tribal basin Has your question been resolved?
<@&286206848099549185>
Ther formula was given already.
I just need to make a problem based on it
so I did it wrong i am assuming.
yeah maybe.
if i follow your problem, i have to ** 48 instead of -48
just think about this.
"Mike wants to save for a future expense by making monthly deposits into an account that earns an annual interest rate of 3.5%, compounded monthly. He plans to make 48 equal monthly payments of $100 each. What is the present value of this annuity?"
Sounds better than mine
They are taking money within those 48 payments so its -
right?
Something like that?
yeah.
It would be this one?
it is reworded better tbh idk where I messed up
48 equal monthly of 100$
no i just like using mike for every problem i make
very easy and generic name 

which grade?
12 mathematics
I have new units every week its kind of awkward ngl
thank you for your help.
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so this year you will graduate?
Yes
good for you.
🫡
us?
born and raised
and now?
same place lol
cool...
yeppers
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no
uh, it's undefined because 0 is in the interval
Then every time we do partial integration we need to check if between the given values diverges?
you cant integrate over a singularity like that
the function needs to be defined over the region of integration
if its not you use an improper integral
You're using the Fundamental Theorem of Calculus in the 3rd step, which relies on continuity over the whole interval you're integrating over
hello mikkel
Hello jan Niku
Huh?
Improper integrals are the ones that the bounds are infinitive?
improper integrals also occur if a function is not bounded for the interval (discontinuity)
improper integrals have bounds that are limited
or infinity, yea, which is just a special case
in your case you need a limit towards 0
yes
should be like this [\int_{-1}^1\frac{1}{x^2},{dx}=\int_{-1}^a\frac{1}{x^2},{dx}+\int_a^1\frac{1}{x^2},{dx}.]
fish
and take limit of a to 0
you want $2\lim _{a\to 0} \int _a ^1 x^{-2} \dd x$
jan Niku
its even so we combine
Oh so it is 2(-1+lim(a->0)1/a)
$a \to 0^{+}$
Mikkel Angelo
sure lol
But this is infinitive $\lim _{a\to 0^{+}} 1/a$
Khwu
Aha so we have infinitive as the solution?
Ah ok so it is undefined
well, say it diverges
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Hey guys. I have to solve this system in R, though I've found out that x = y = z, I'd like to prove that also, and I don't know how.
So please help me prove that x = y = z
what is 'in R'?
@blissful depot Has your question been resolved?
real
numbers
anyways, I solved it with calculus
thank you anyways
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does this proof of mine work?
#1260424130822541403 message
@pastel orbit Has your question been resolved?
Ima read this
Had to remember topo but yeah, are you unsure of somewhere in the proof ?
no, I'm just looking to verify its correctness 
Ok, i dont see anything wrong while reading, not familar with this version so maybe someone who could double check would be better ig

What level is this ?
what do you mean? 
it's not tied to any specific grade I suppose
different places will teach it at different times
Here in germany, this basic topology is taught in "Analysis 2" in second semester. 🙂
And what could you say about his proof ?
I havent really read it, just went over it and scanned if there are concepts in it i havent yet heard of
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any idea of this
a u-sub of u=lnx seems like the way to go
how to deal with this part
@heady plover Has your question been resolved?
<@&286206848099549185>
wtr.on
ok then if u=ln x, it will be $\frac{\ln(\frac{e}{x^2})}{u}$
nino
$\int_{1/e}^{e} (u)^{\frac{\ln(\frac{e}{x^2})}{u}\right)} \left(1 - \ln(u)\right)du$
nino
Compile Error! Click the
reaction for more information.
(You may edit your message to recompile.)
$\int_{1/e}^{e} (u)^{\frac{(1-2\lnx)}{u}\right)} \left(1 - \ln(u)\right)du$
wtr.on
$du=\frac{\frac{-2}{x}\ln x-\frac{1-2\ln x}{x}}{(\ln x)^2}dx=\frac{1}{\ln^2 x}dx$
nino
$\int_{1/e}^{e} \frac{(\ln x)^u \left(1 - \ln(\ln x)\right)}{x} (\ln^2 x)dx$
nino
wait how to continue
no
ye i've known that
dx/x is d(lnx)
ye but i stuck, you can take a try, i dont think taking u as lnx will work
Ohhhh
i know where is the problem
I cant solve it now
but i believe the first step is d(lnx)
$\int_{1/e}^{e} \frac{(\ln x)^{\frac{1-2\ln(x)}{\ln(x)}} \left(1 - \ln(\ln x)\right)}{x}(-x\ln^2(x))dx$
lnx=1/(u+2)
ok then how can we continue
wtr.on
darn....
how did you come up with that...
any tricks?
so once you see the power part being like a form a(x) then treat it as u?
You mean the problems which treating the power part as u?
darn...where can i find problems like that....
I never met such problems before
I guess yes
But igtg rn, if i didn't make it successfully,I'll ask again, Anyway thank you so much
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@signal oar Has your question been resolved?
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help
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I must decide values for x and y
Ive come to: log(2y)=y/5
But I dont know how to solve further
How did you arrive here?
eq 1. can be simplified to log(xy)=1, xy=10 gives that x = 10/y
Putting that into the next equation, 10/y * log (2y) = 2 => log(2y) = 2y/10 or just log(2y) = y/5
I would just guess random integers for y.
Might help to get y in terms of x and plug into the logarithm? Haven't solved through though
Maybe try to make the log expression a power of 10
yeah thats what they say in the solution
but isnt there a way to solve this without guessing?
No
You would need the Lambert W function
I believe it's also known as the product log
If youre able to manipulate such that you can apply the lambert W function i would say its totally legit
But it's not very helpful for you, as it is simply defined as the solution
its really no different than applying the square root to something
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I'm doing some conversion practice and I need help. I know that the answer for the numberator in the second box is 28.3168 L/ft^3 but there is no 28.3... in the blue answer bank. So what do I do? Am I converting incorrectly? What do I need to do to get the correct answer as 99 L/s?
There is an extra conversion you have to do
You can go from Liters to cm to ft
In order to cancel the ft correctly
Do you mean in the second box to go from L/cm x cm/ft ?
Yes
Do you mean cm or cm^3
Okay, I fixed the second box, now the third box is incorrect
The numerator needs to be 30.48 cm I think
@small oxide Has your question been resolved?
Not yet
@small oxide Has your question been resolved?
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yo guys
Can't guarantee an answer
why is Hydrogen ion not considered basic radical
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why does lim x approaches 0 of (e^x-1)/x equal 1?
Its a rate change so its the derivative of e^x in 0
Ima share the image
Let f(x) = e^x
is there some other proof of this?
L'hôpital
?
Like you can apply l'hôpital rule to the limit
I mean some proof of this that doesn't depend on derivatives
that's worse than using the derivative limit
Yes
But without derivative i dont see actually
since a version of this limit appears as you try to differentiate e^x
?
l'hôpital is literally taking derivative of both numerator and denominator
No i meant a proof without derivative
what's your definition of e^x
Mb
in the classic def of the derivative of e^x, you get lim as dx approaches zero of e^x times (e^dx-1)dx after a bit of fiddling, I remember my teacher giving me a nice explanation of why the (e^dx - 1)/dx part equalled zero but I forgot.
?
That doesn't answer my question
what does "e^x" mean to you
how was this introduced to you
i guess, lim as x approaches infinity of (1 + 1/x)^x
i don't know any other definitions
yeah
how was log defined
the inverse of a exponential
ok this is really weird
because how did you even define e^x then
did they teach you what it means to take a real number to the power of a real number
just e to the x power?
uh huh, what does it mean when x is any real number
I don't really know
then your definition is bad
so
I agree about the definition of e, whatever it may be
it's a number
but if we can't explain what it means to take e to the power of a real number
then we can't define it that way
so instead
we can define the exponential function first
and it's not gonna depend on "e"
have you seen infinite sums before?
yeah
rafilou2003
and let's consider the infinite sum $\sum_{n=0}^\infty \frac{x^n}{n!}$
rafilou2003
does this converge?
yeah
yeah, you can take ratio test for example
so this, converges to some value
that we will call $\exp(x)$
rafilou2003
we have defined a function that takes real numbers as input, and outputs real numbers
now
we're gonna prove two things:
- this function's derivative is itself
- exp(1) = e
then, we can give sense to the expression "e^x"
as it will refer to exp(x)
and it's gonna correlate with the value we expect it to be when x is an integer
(we know how to define what a^b is when b is an integer)
so
let's try point 1)
how do we differentiate an infinite sum?
that should be infinte sum of nx^(n-1)/n! , if I didn't goof up
yep, exactly
just a small problem when n=0
that we would better solve
the derivative of x^0/0! = 1
is 0, since it's a constant
so we can remove the "n=0" part
and the other terms are good
$\frac{d}{dx}\sum_{n=0}^\infty \frac{x^n}{n!} = \sum_{n=1}^\infty \frac{nx^{n-1}}{n!}$
rafilou2003
but notice
that n! = n * (n-1)(n-2)... = n * (n-1)!
so we're left with $\sum_{n=1}^\infty \frac{x^{n-1}}{(n-1)!}$
rafilou2003
and if you push all of the terms to the left
oh damn, I see it now
rafilou2003
boom, $\exp(x)$ is back
rafilou2003
we have found that $\exp' = \exp$
rafilou2003
point 1) done
that's an approach I've never seen before. I guess it's becuase they teach series pretty late in the curriculum
yeah, the problem with trying to use exponential without REALLY defining it is that it leads to shitty definitions like the previous one
where you can maybe intuitively see what e^1, e^3, e^integer is... even e^(rational)
but e^pi ?
so with exp' = exp
by definition of the derivative
I always just though they took the limit as x approaches some irrational number when trying the wonky stuff
$\frac{\exp(x)-\exp(0)}{x-0}$ converges when $x\to 0$ to $\exp'(0) = \exp(0) = 1$
rafilou2003
is it well defined?
like if I take two different sequences of rationals that approaches an irrational, do they have the same limit?
i got no idea
so see I feel like this "definition" is even harder to properly define than the one I'm showing you
anyways
with this we finally have $\lim_{x\to 0}\frac{\exp(x)-1}{x} = 1$
rafilou2003
now we only have to show that exp(x) is the "same thing" as e^x
so let's start with showing point 2), that exp(1) = e
this stackexchange discussion shows it better and quicker than I would manually https://math.stackexchange.com/questions/4025559/how-do-i-prove-exp1-e-if-exp-is-defined-in-a-series-expansion
alright, thanks man
and final thing
after proving that exp(1) = e
for more reassuring it would be nice to know if we also have exp(n) = e^n for any integer
this is where the "exponential property" comes into play:
$\forall x,y\in \bR, \exp(x+y) = \exp(x)\exp(y)$
rafilou2003
(just like you would expect with exponents)
to prove this:
fix some value of y
and we're gonna show that the functions $f(x) = exp(x+y)$ and $g(x) = exp(x)exp(y)$ are equal
oh it is the way oops
now, what we would like to do is to study the function $\frac{f(x)}{g(x)}$
rafilou2003
problem: if g(x) = 0 somewhere that's not possible
so what we need to do is to show that exp function doesn't equal 0 anywhere
hope you're still following
we're almost out of the rabbit hole I promise 😅
I'm following what you're saying, but I'm not really following why proving that exp(x+y) = exp(x)exp(y) would help with proving that exp(n)=e^n. I haven't really figured out what they're saying in the stack overflow chats so that might be why
haha it's kinda by induction
once we have exp(x+y) = exp(x)exp(y)
and since we know exp(0) = 1, exp(1) = e
then exp(2) = exp(1+1) = exp(1)exp(1) = e^2
exp(3) = exp(2+1) = e^2 * e = e^3
do you see it?
oh, I see
to prove that exp(n) = e^n for any number we just gotta prove exp(x+y) = exp(x)exp(y) becuase it's already established that exp(0)=1 and exp(1)= e
going back to this, let's prove exp can't be 0 anywhere to make this function have sense
welp, it's by looking at $h(x) = exp(-x)exp(x)$
rafilou2003
we can compute its derivative using chain rule and product rule
$h'(x) = -exp'(-x)exp(x) + exp(-x)exp'(x) = -exp(-x)exp(x) + exp(-x)exp(x) = 0$
rafilou2003
so h is constant
and h(0) = exp(0)exp(0) = 1
so
for all x
h(x) = exp(-x)exp(x) = 1
we've proved exp(x) can't be 0
and 1/exp(x) = exp(-x)
so this function can be defined
anyways you get the gist, we can differentiate f(x)/g(x)
we'll get the derivative is 0
so f(x)/g(x) is constant
and f(0)/g(0) is, you guessed it, equal to 1
so f(x) = g(x)
meaning $\exp(x+y) = \exp(x)\exp(y)$
rafilou2003
so we're finally done
I see
I'm just slightly confused about these functions. f(x) = exp(x+y), for these functions the "x+y" in the exp() has nothing to do with the
"x" in f(x) right?
anyways thank you
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it does, x is the variable
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How does this derivation go?
@cedar magnet Has your question been resolved?
@cedar magnet Has your question been resolved?
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@cedar magnet Has your question been resolved?
@cedar magnet Has your question been resolved?
@cedar magnet Has your question been resolved?
its unclear what exactly you are asking. the text says how the argument works
what exactly do you want to hear
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hii how do i do 5.(iii)?
i have this so far but im not sure if i put the correct term in the bracket
<@&286206848099549185>
i did this so far but im not sure if i need the x fully gone or if theres supposed to be one x term
no like i mean in the second bracket if i use the 6th term, theres no x
but if i open the brackets then thrs gnna be the 1/x^3 left
no matter what term i use i cant get the x gone😭😭
sure but im not sure what the n Z k=0 looking thing is
girl i have no idea what your talking about
i dont know if in us or what state are you from the binomial theorem or sums are in 10th class
hmm
but how do i get a term independant of x frm here?
We look for the terms for which his power 𝑥 is zero. That is, we determine the terms for which the exponent of x is zero.
but if i multiply that in thrs still the 1/x^3 left
we will make it disappear
then replace k = 6 in first bracket and k =5 in second
calculate and you will find that the independent term for x is 252m^6 - 125m^5
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help😭 how to solve for c
!noans
The purpose of this server is to help you learn, not to hand out answers. Do not ask someone to give you the answer directly.
oh mb
Anyways
It is so hard
oh thanks
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I got up until
the last step
I don't get why
the negative sign
becomes positive at the end though
they switched the bounds
^
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Sooo i have summer school and this teacher is saying 2+2 is not 4 its some weird equation can sum1 help me solve this
erm
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oh sorry
R = 9
What is the answer?
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How does one take on this?
b_7 = 96 or b_7 = 960, right?
i think just solve for the first 9 terms in terms of b_7??
b6 = 96 and b8 = 960
yeah but we know that b6 | b7 | b8
and 960/96 = 2 5
so it can't be 96 2 or 96 5
so it has to be either 96 or 960
Hmmm
we also know
b8 = b7(b6/b5 + 1)
-> 960 = 96b7 / b5 + b7
-> (96b7)/(960 - b7) = b5
so b7 better not be 960 then
?
Hmmmm
yeah this actually just locks b7=96
wait
no
what's the mistake?
because b7=96 gives noninteger for b5
oh i'm too dumb ain't i
So b7 = 960
this all is wrong
it can actually be 2 96 or 5 96
sorry too fried
but either way we have
(96 b7) / (960 - b7) = b5
b5 = 24(if b7 is 192) or 96(if b7 is 480)
Okay Okay
b7 = b6(b5/b4) -> b4 = b5 b6 / b7 = 24 96 / 192 or 96 96 / 480 = 12 or 19.2
but 19.2 is not integer
so b4 = 12
Hmm
b5 = 24
b7 = 192
b6 = b5(b4/b3 + 1) -> 96 = 24(12/b3 + 1) -> 3 - 1 = 12/b3 -> b3 = 6
b5 = b4(b3/b2) -> 24 = 12(6/b2) -> b2 = 3
b4 = b3(b2/b1 + 1) -> 12 = 6(3/b1 + 1) -> b1 = 3
b9 = 960 (192/96 + 1) = 2880
giving average of 464
there are 4 options it can be because of the divisibility rule
then just take it as unknown for now and rearange the definition for b_8 to solve for b_5 in terms of b7
you will see that if b7 = 960, then there is no solution for b5, and if it is 96 then the solution is noninteger
so now you know that b7 is either 192 or 480
and then you can do it on case by case basis
again
solve for b4
and you will see that b4 is only ever integer if b7 was 192 to begin with
because b7 = b6 n and b8 = b7 m
so really i was thinking b8/b6 = 960/96 = 10 with factors of 1, 2, 5, 10
so b7 has to be 96 x one of those factors
OH I SEE
So what are the values for b1 to b9?
b1 = 3, b2 = 3, b3 = 6, b4 = 12, b5 = 24, b6 = 96, b7, = 192, b8 = 960, b9 = 2880
Holy
The problem though
There is a floor A
It's equal to 464 or its meant to put us off?
OKAY I GET IT
THANK YOU VERY MUCH
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Relative to a fixed origin O, the point A has a position vector -2i + 3j. The point B has a position vector 3i + pj, where p is a constant. The point C has a position vector qi + 7j, where q is a constant. Given that |AB| = 5 * sqrt(2), (a) find the possible values of p. Given that the angle between AC and the unit vector i is pi/3 radians, (b) find the exact value of q.
I got part a pretty easily but using the dot formula produces two possible answers for q, ignoring how these answers aren't nice numbers, the question said that there was one exact solutions. the specification normally specifies if there are multiple possible solutions in the question
ik i was talking about q
yh
alr, one minute
cool
so
(q+2)=1/2 [sqrt(4^2+(q+2)^2]
(q+2)^2=1/4 [ 4^2+(q+2)^2]=4+1/4(q+2)^2
then 3/4 (q+2)^2 = 4 (q+2)^2=16/3 q=+-4/sqrt(3)-2
since it says theres one im guessing one of the cases doesnt actually fulfill the dot products equality
you can check that
.
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what?
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I mean I got the right answer but I kinda just guessed
I have no idea how to do this question
Like theres nothing inside the integral\
Yes please haha im a bit confused
it’s basically taking the integral of 1
Sry if this is a dumb question but wheres the 1
the antiderivative which you got correct is x +c since it’s undefined ( no lower or upper )
here
it’s not dumb but think of it as multiplying it by one like gizmic said
Feels weird tho haha
in what way, i can try to explain further if i can
Nah its nothing, I think I get it 😄
you sure ?
Yeye haha
if you have any more questions feel free to dm me
okayy good luck
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By 'circle O', is it meaning that the centre of the circle is labelled O?
"given {O;R}" means given a circle with a center of O and a radius of R
but circle O can still be understandable depending on context
@autumn vine Has your question been resolved?
lone circles are usually named by their centres
if there are multiple circles present with the same centre, then more info would be included to distinguish between them
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National Oric Mathematics Competition 2024
Problem 1)The diagram below displays a permutation of the letters "A, B, D, E, F, J, O,.....". This permutation permits repeated letters, and no letter or order shall be removed. What is the letter at the 2024²⁰²⁴th position? (10 Marks)
private competition. non public
the question is just following the pattern, and 2024²⁰²⁴ i believe can be simplified
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in (0,0)
use the formal limit definitioin of differentiation
we're in 2D, only partial derivatives have limit definitions
but you can certainly try to compute the gradient this way and see if it makes sense
I've already did the partial derivatives
1 for x 2 for y
but I don't remember the formula after that
there is a theorem that implies if you have cts SO partials around a point, then it is diff'able at the point
?
just recall the formula for 1D differentiation
$\lim_{h\to 0} \frac{f(x+h)-f(x)}{h}$
rafilou2003
and for multiple dimensions partial derivatives
just place the "+h" on the direction of the derivative
$\frac{\partial f}{\partial y}(x,y) = \lim_{h\to 0}\frac{f(x,y+h)-f(x,y)}{h}$
rafilou2003
check if the partial derivatives are continous at (0,0)
if they're not, this doesn't tell you if the function is differentiable at (0,0) or not
so since you've found the partial derivatives
you have the gradient
$\grad f (0,0) = \begin{pmatrix}1\2\end{pmatrix}$
rafilou2003
that means if $f$ is differentiable at $(0,0)$, then $f(x,y) = x+2y + o(x,y)$
rafilou2003
in fact, you need to prove that $\frac{f(x,y)-x-2y}{|(x,y)|} \to 0$
rafilou2003
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thanks!
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I know this is a maths server but am desperate
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can someone help me
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how can L < 1?
Ayanokoji (ALWAYS PING ME)
!original
Please show the original problem, exactly as it was stated to you, with the entire original context. A picture or screenshot is best. If the original problem is not in English, then post it anyway! The additional context might still be helpful. Do your best to provide a translation.
...a sequence
to be clear this is the if
and this is another if
but a_n doesnt converge 0
to the result you see a_n -> 0
however, if L is in (-1,1) then yea its true
in english these are the conditions for the "fraction" or "quotient" convergence test for sequences
because of L is in (-1,1) then |L|<1 a_n will appraoch 0 slowly for each term in the sequence
but your example doesnt satisfy the conditions, L = 1
oh wait
i see
im guessing they meant to write |L|
i found this
i highly doubt it
yea thats the same
doubt what
oh i omitted a detail they said, that a_n > 0 for all n
yea then sure
it's kind of useless to put this condition when the theorem should be for absolute values
L can not be negative
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no problem ahoy
.reopen
✅
umm i just realized i still dont understand why a_{n+1} > a_n
i mean lim a_i = lim a_j as far as i know
hm?
since both go i,j -> inf
where did this come from
yes, what about it?
whats the sequence?
2/2^n
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np
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I want to look up videos / content explaining this question but I don't know what kind of keywords I should be searching to find this.
@lapis bobcat Has your question been resolved?
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I'm stuck with this double integral, especially with the domain after the swap of coordinates. I need to set integral bounders for u variable. Moreover I've already obtained them for v variable but I'm not sure it is the correct way
From solutions it should be $u\in[0,2]$
x_Shadow_x
For v variable $u+2 \leq v \leq 6-u$ as I obtained, but I'm not sure my procedure is right since I take the second function of $v \geq 2+u$ and i put it in the place of $v-2u \leq v$ as I show with the arrow
x_Shadow_x
@rocky smelt Has your question been resolved?
@rocky smelt Has your question been resolved?
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pls
What's the exercise?
wdym
The image just shows an angle
gotcha
any thoughts on how to start?
hmm can you make an estimate
eyeball it
The idea is that you know $\angle DBA = 133 ^\circ$
hmm whats the command
jan Niku

and we know part of DBA right?
so, DBA is made up of two angles
$\angle DBA = \angle ABC + \angle CBD$
jan Niku
Your task is to identify which of these 3 is known or unknown
