#help-28
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can you just turn it into an algebraic problem and solve for y=0
π
.
i wish i could turn it into an algebraic problem
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Hi if anyone could confirm my working for part I that would be lovely and also explain how to start the second part !
I did star a line because im not sure if thats an actual thing yiu can doβ¦
looks good but the way you do this seems quite weird
you can just differentiate dt
instead of involving this dv/dh stuff
$\dv{V}{t} = 20\pi h \dv{h}{t} - \pi h^2 \dv{h}{t}$
knief
But my question asks for the depth changed so isnβt that dh on dt
treat V and h as functions of t then differentiate both sides wrt t
yes
which is what we want
you isolate dh/dt here
$\dv{V}{t} = (20\pi h - \pi h^2) \dv{h}{t} \implies \dv{h}{t} = \frac{2}{100\pi - 25\pi} = \frac{2}{75\pi}$
knief
Yay okay thank you sm
plug in 2 for dv/dt and 5 for h
Yes i see thank u
ok so part 2 you need help with?
well we need to write V as a function of r yes?
in order to find dr/dt we are going to have to somehow relate r to V or h
beside like A.... but idk why id use A
since we know dv/dt and dh/dt when h = 5
yes but idk how to
do you know the volume of a hemisphere in terms of r?
um ngl no
if you know the volume of a sphere then this should be easy
a hemisphere is half a sphere
do you remember this?
okay nvm its given to me
4/3 pi r^3
so for hemisphre its that divided by two right
so can i do dr/dV maybe?
ill try that
should i use
so we should really try relating r to h instead
where did you get this?
what is A here?
area of the water surface
oh
yea i think that should work
you mean then relate it to the equation you had strictly in terms of h?
yea 1/3 pi h^3(30 - h)
okay now my answer seems ridiculous tho
what did you get
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i dont understand how to solve the problem
no info about the curve itself is given
well, do you really need the curve? All you need is O, A and B, all of which are known and do not depend on f(x) at all
draw a figure and you should be able to how you need to proceed
so a trianlge
passing throught 3,4
so how do i use the info that the sub tan and sub norm is equal
i didnt rlly get how to put those in the figure
do you know what a subtangent and subnormal is?
the x axis projection of the tangent and the normal
yes, and your problem tells you that those two are equal
that tells you something very specific
so they are at an angle of 45 from the origin?
then only they will have the same projection right?
yea
well, at this point, you have two choices for the tangent
an isoceles triangle
wait what are those
with its tip as the point 3,4 is what im thinking'
lengths of projections on x-axis, between the point on curve to the point of intersection with the axis
not really, (3,4) is not A or B or O
and those three are the vertices
at that point we know that
im thinking we take 2 of these triangles
add em to get the AOB triangle
like aob is right angled,
well, that was always gonna be the case, considering x axis and y axis form the two sides of triangle AOB
isosceles right triangle is more relevant here
ye π
why will the x and y coordinates be the same
coz the slope of line AB is gonna be 45deg
thats why I said draw a figure
well, you have two choices about what the tangent is gonna be, one is with positive slope, the other with negative slope
Man i dont even know simple math im here to lock in
calculate both the areas and see which one is larger
????
uhh
did you draw a diagram yet??? 
well, in your hypothetical diagram, what you took to be a tangent and a normal can be swapped too
yes thats true
so that gives you the other choice of OAB
ull get more area only if its having -ve slope
yes
but the point thats 3,4
and??
is the midpoint of the isoceles right angle?
so it lies somewhere along that line
whats a midpoint of a triangle
not the triangle, im talking about the hypotenuse
then how do i find the area π
just find the intercepts of the line thats the hypotenus???
uhh
how do i do that
whats the equation of the line?
its gonna be the same cuz its a isoceles triangle anyway right
yea
yep
i got the ans but it seems like the idea of using the line eq would not pop in my head normally
does the question hint at using the eq of line somewhere?
you dont really need to tbf
in exam id 100% get grilled
oh is there another approach
if you draw the diagram you can see it, you dont have to calculate
like just pulling the point 3.4 along x and y axis?
to get both as 7
well, you see that the line is gonna be 45deg
yeah
you dont need to rigorously find the equation and all that, it all gotta flash in your head like that, and then ofc you can write the solution on paper for your exam step-by-step
np
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$ABC$ is a triangle, with $M$ being the midpoint of $AB$. Point $D$ lies on the arc of $AB$ that does not contain $C$ such that $BD$ is tangent to the circumcircle of $BCM$. Point $E$ lies on $AD$ such that $BE$ is parallel to $AC$. Point $F$ lies on $CE$ such that $\angle EAC=\angle EFA$. Prove that $FM$, $CA$, $BD$ are concurrent
ihave<skissue>
holy shit... is this what geometry has become
uhh.... im not expert but... probably some geometry mumbo jumbo that results in the points all being on one line
@hoary ember Has your question been resolved?
I think by angle chasing you should be able to see that:
A, M, F, C are concyclic
E, D, B, M, F are concyclic
oh wait is the idea like that one thing about the 3 radical axis of 3 circles are concurrent or smth
From there the concurrent point is just the radical center of the 3 circles (AMC), (BMD) and (ABC)
yea you got the idea
mm lemme think on proving this
i think the latter might be a lil tricky but havent tried
huh
ok might start with A, M, F, C
since we dont know the property of MF yet it's better to prove MAF = MCF
nvm AMC = AFC is much easier
umm they arent parallel
@hoary ember Has your question been resolved?
damn
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Can someone explain how to do these? I don't understand how to figure out the behavior of f using f'
what do "increasing" and "decreasing" mean?
do you know?
When the slope is getting positive or negative?
which means when the derivative is positive or negative, right?
because derivative = instantaneous slope
So for example the first one is increasing (-3,-1.5) and (1,3) ?
no, because the problem gives you the graph of f'(x), not f(x)
you're seeing when f'(x) (the derivative of f(x)) is positive or negative
So it's increasing (-2,-1) and (2,3) because those intervals are postive?
What about for maxima and minima like this problem?
for maxima and minima, you know f'(x) = 0
the way you tell max/min apart from each other is by seeing if f'(x) goes from positive to negative, or, negative to positive
take x=-1 for example
f'(-1) = 0, so it is either a max or a min
because f'(x) goes from positive (before x=-1) to negative (after x=-1), it is a maxima
now you do the same for the other times when f'(x) = 0
Okay i got
X=-1 max
X=0 min
X=1 max
Im not sure about -2 and 2
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this is from an old book
is this norm on the LHS and abs value on the RHS?
what even is $x$, i need more context
Sunny β ping me plz
like the natural assumption is to assume $x$ is real, in which case i dont know what you're talking about with norm
its from the spivaks calculus on manifolds book
you might wanna show us the whole picture of the question
that is the question
does the question directly start with 1-1 and a fullstop?
thats the context. this is a book from the 70s
because is this is an abs value on the RHS this makes sense
is $x^i$ notation for like the $i$-th term?
Sunny β ping me plz
it seems more of a condition for every term from i = 1 summation till n.
that x to the power of i is the condition for every term that we get from the summation function
and we prove that x is less than Or equal to it
this would make sense, and in which case, yeah, it would work
so the length of a vector is always less or equal to the sum of its absolute components, interesting
It would
it makes sense, its how i read it but it took me 20 minutes to come to that conflusion
since this is manifolds, i dont think this is necessarily "length of a vector"
love the accidental typo
pardon me, i should have used norm
my kid dropped a soda thats jammed up my keyboard :P'
i'll now officially use "conflusion" as a portmanteau of confusion and conclusion
haha.
okay yeah this is easy to prove then.... take the square of each and move down
Mhm
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@lean rock Has your question been resolved?
or for codiagram?
A pushout of a copair of C-coarrows with a cocommon domain is a colimit in co-C co-for co-the codiagram!
this seems. a bit tricky:
for pushout which arrows pushout out along which arrow?
this is the original:
c--g-->b--f'-->d
c--f-->a--g'-->d
f' is pushed out along g? so f arises?
g' is pushed out along f so g arises?
or
f' is obtained by pushing out f along g
g' is obtained by pushing out g along f
g
c ββββββββΆ b
β β
f β β gβ²
βΌ βΌ
a ββββββββΆ d
f'
g' is the pushout of g along f
f' is the pushout of f along g
β§
Oh I didn't reverse the arrows,, the diagram seems the same diagram as that of pullback
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Can someone help me with qn 5 (IV) and (v)
What have you tried?
use d(u/v) = (vu' - uv')/ vΒ²
Hmm alright thankss
Assuming they know how to diff g^-1 π
I mean, I believe they've learnt chain rule so maybe yeah
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Can someone help me understand maths from absolute scratch based on complete logic.
no
please be more specific β what do you really want
Allow me to rephrase
I'm looking for guidance on how to learn mathematics from the absolute basics with a logic-first approach. I need recommendations for books, the sequence to follow, and how to study, obviously I don't want to be spoon-fed, just direction.
right, that's much better than "Can someone help me understand maths"
uh
I'm not sure actually β and I would ask the same question
Yeah, I agree. It was sloppy english lacking intent. One could clearly tell I myself had no idea what I was talking about.
@dry eagle Has your question been resolved?
Go on youtube as for us we went though primary to high school and this varies from country to country so i think going to youtube or even on reddit or stack exchange past posts u will get your answer
I'm in high school. But math sucks here. Half-ass explanations and stuff.
I wanna learn it properly.
It is high school if u go to univ u will understand in more-detail assuming u will be doing maths at uni.
I want to learn it from basics.
Like High-school doesn't teach maths correctly. At least my school doesn't for sure.
Did u refer to youtube beucase they some famous mathematician there
Could you tell me the name of that mathematician?
This video shows how anyone can start learning mathematics , and progress through the subject in a logical order. There really is no finishing point but this will get you through all of the basic undergraduate mathematics from start to "finish". I also included some graduate topics.
Here are the books that showed up in this video(in order) on ...
The Maths Sorcerer
Thanks a lot Beluga.
Or Mr.Beluga.
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the cost of two pies is the same as the cost of 3 patties. one pie and one patty tigether cost 3.50. what do they each cost
i dont understand it
yes
Now we are said, cost of 2pies = cost of 3 patties
=> 2x = 3y
This is first equation
You follow?
yes
ok so
Go on
u have to subtract 2x = 3y from another equation
You prefer subtracting?
well when the 2 signs are the same u subtract right
and when the 2 signs are different u add'
Yes but first need to make coefficient equal
Write it as
2x - 3y = 0
x + y = 3.5
Can you make coefficient of x in second equation sane as 1st?
Multiply then subtract two equation
so 2x + 2y = 7.00
Now subtract 2x - 3y= 0
0x + -1y =7.00
oh
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am i right?..
btw forgot the parenthesis
Is it 37*(2/5):3 in the first steps denominator?
yes
(2/5):3 can be written as 2/5/3 or 2/3*5 or 2/15
. is multiply
: is ratio right
And yes . Is multiply so you multiply 37 by 2/15
Results 74/15 in the denominator
why 5 * (x + 0.28)
that 5 was from ur previous fraction which was incorrect
it should just be the
(original numerator) / (74/15)
@azure junco Has your question been resolved?
wait
= (x + 0.14 x 2) / (74/15)
= (x + 0.28) / (74/15)
> 15 moves up to the denominator, same logic as the one you used in your original solution
= 15*(x + 0.28) / 74
= (15x + 4.2) / 74
I'm guessing this is sufficient as the final answer
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Is there a methodical way of finding the expected number of coin tosses before seeing some generic pattern of heads and tails?
The methods for a specific pattern depend on some casework and that doesn't really seem to generalise well to the generic case
well u can use bernoulli trials
well sure, each coin toss is a bernoulli trial
I don't really know what markov chains are
unlucky
what
but here it is an independent event, isnt it?
.close
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thats correct no?
only the sign is flipped
should be 1.8
can you show me what you did maybe i can spot where you messed up
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That chemistry server is dead
Iβm just trying to clarify something with chemistry although this is a math server, should it be Na3PO3 + H20 for the products
Pls help
Yeah
When I ask ChatGPT it said NaHPO3 thatβs wrong?
!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).
this isn't balanced though
i dont think
okay
But Iβm just not sure if itβ Na3PO3
Wait I got it nvm
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howd they make
1/ 6 - x to
1/ 5 - (x- 1)
so i see the (x- 1) part because they want the C = 1
but what happened to the 6 howd it become 5
5 - x + 1
?
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can anyone help
There are n choose r ways of selecting r things from n objects
- is by definition a simple n choose r with n and r given
i donβt understand at all
Which word confuses you
im trying to relate permutations and stuff
its that i try to build on previous knowledge
Then don't?
This is all you need
0 <= r <= n of course
but arent you supposed to connect this with things about permutation counting
Not if you keep getting stuck
can you explain it though
im stuck cause i dont know how to make the connection
.
Then do problems that relate them. Your problem doesn't
okay can i ask what the intuition is behind r choose n
The reason im attempting to relate it is cause i donβt understand the intuition im trying to figure it out
do you understand permutations?
yes
ok so perhaps you should think of it in terms of that
I understand product rule
and permutations
ok so divide the number of permutations by r! because there are r! different orderings of the objects you select
how would that look like here
We are looking for how many 4 subsets there is right
so letβs label the people first
Okay
say $a_1, a_2, \dots, a_{12}$
knief
we have 12 choices for the first person to pick, then 11 for the second, then 10 for the third, and 9 choices for the fourth. however, within this group of 4 people we just chose we can shuffle them 4! different ways. so we couldβve for example chose the first guy second and the second guy third and the third guy first and the fourth guy stays the same etc. hence we will overcount and get a count of 4! ways corresponding to this particular group of 4 people. this is true for every group of 4 people we choose as well hence why we divide the total count 12 * 11 * 10 * 9 by 4!
$a_1a_2a_2a_4, a_1a_4a_2a_3, a_2a_3a_4a_1, \dots$ all correspond to the same group
knief
this is true for every group
so we have an extra factor of 4! in our count for the number of groups
note that this matters because their positions in the group are indistinguishable, itβs not like one person is the president and another is the vice president and another is a secretary and the last is a treasurer or something
these are all considered the same
whereas if we had different "positions" like president, vice president, etc. then the orderings within the group would matter
does this make sense?
maybe you should consider a smaller example where itβs easier to list out the permutations
then youd look at the number of 4 permutations of the set right
yea that would be a permutation problem
But youβre saying that because order doesnt matter you divide by 4!
yes
but why does that work like that
because each group we chose actually gives us 24 different ways when we count like 12 * 11 * 10 * 9
i just explained it
how about we use a smaller number
Okay
letβs say i have 4 students a, b, c, and d and i want to know the number of ways i can make a group of 2 students. so i have 4 choices for the first and 3 choices for the second giving me 12 total permutations
ab, ba, ac, ca, ad, da, bc, cb, bd, db, cd, dc. now we treat the groups ab and ba as the same since they have the same students and likewise we treat any permutations with the same two letters/students as identical. now for each group of two distinct students there is 2! =2 ways to order them so each individual group gets counted 2! ways in my original count of 12 ways to form the group of 2 students from 4. hence i have 2! times the amount of "groups" iβm looking for in my count so to correct for this i divide my original count by 2!
and what does all this have to do with mapping permutations to subsets?
because thats what theyve been talkin about too
if i select r objects then there are r! permutations of those objects that map to a particular subset consisting of distinct elements
so my count has r! times the amount of ways i want
so we divide by r! to get the subsets that donβt care about the ways i can order those r folks
wdym by r objects
how is that possibly confusing
r is just a variable
n choose r
i was relating it back to that
in the general case
i think the frustration is making this confusing so ill give it some time
are you in uni?
@torn jolt Has your question been resolved?
you could say that
whats your major?
Undecided yet
any plans?
im a math major
niceee
can i go back to our question real quic
i though about it for a little
sure
why do we divide by r! I dont get that part
because counting the permutations gives r! times the amount of subsets of distinct elements where order doesn't matter
see here
oh nah too competitive and market is going down
also they require like a 3.9 GPA or something
@torn jolt Has your question been resolved?
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hi
im trying to solve t^2y'' + 2ty' - 6y = 0
using this sub: t = e^x
so y(t) = y(e^x)
y' = dy/dt = dy/dx . dx/dt = dy/dx . (1/t)
y'' = dy'/dt = d( dy/dx . (1/t) )/dt
so y'' = -1/t^2 . (dy/dx)
1/t . d(dy/dx)/dt
so what is the last term?
d(dy/dx)/dt
is it y'.(dy/dx)?
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not sure how to get the derivative of 10e^5t
you here?
yeah
can you find the derivative of 10e^t?
5
now have you learned chain rule?
yep
can you try it?
oh sorry i know how to do that
sorry i went afk
i meant to say idk how to get the antiderivative of that
can you find the integral of 10e^t?
im not sure
ok think about this
the antiderivative should be the opposite of the derivative, right
yeah
and you said the derivative of 10e^t is 10e^t again
so why cant the antiderivative of 10e^t just be 10e^t again?
i guess it is right
well it isnt
you forgot about the +C
but other than that its right
the antiderivative of 10e^t is 10e^t + C
in general the antiderivative of f'(x) is f(x) + C
yeah
do you know where the +C comes from?
yeah
alr thats good
now we need to think about finding the antiderivative of 10e^5t
to do this, we need a reverse version of the chain rule
a common example is called u-substitution
have you learned u-sub yet?
5t
so it would just be (10e^u)*1/5
so basically 2*e^u
im kinda stuck on how you would rearrange this
because each term is cubed
back
you need to write down the full integral as 2e^5t + C
its inside of a ln, you dont see any ideas with that?
log properties but since its an infinite sum im not sure
like could u do 3^n times ln (1+1/n) +etc?
idk
thats not how you pull 3 out of this
what does it look like instead after you pull the 3 out?
how else can u pull 3 out?
this is not at all correct
think about ln((xy)^3) = ln(x^3 y^3)
thesea re the same thing because (xy)^3 = x^3 y^3
but the rule you stated thinks 3 ln(xy) = 9 ln(xy) instead
review the logarithm rules more closely to confirm this
yeah
ln(x^3 y^3) = ln(x^3) + ln(y^3) = 3(ln(x) + ln(y)) = 3 ln(xy)
so here, what would the result be instead
why does the ln y term not have a 3
nino
look at it again
I inserted some ()s around the ln(x) + ln(y) while you werent looking
without even editing the post (wow!)
XD
now go back to this problem and factor the 3 out, what do you get
i still dont feel like i fully understand how to apply it
mtt
,,\ln(x^3)=3\ln x
mtt
at a minimum you only need these two rules to factor the 3 out of the expression
do you know both of these rules?
yes
second,
do you know what a limit actually does?
yes
then is the sum practically infinite?
or actually infinite?
im not sure what that like means but the 1/n terms will approach 0
ok no thats not what Im asking about
you didnt want to pull out the 3 because the product or sum "looked infinite"
the purpose of a limit is to rewrite down an otherwise infinite thing as a pattern of finite things
so any time you do any algebra on this
n is finite
if you attach this on the left
n is still finite
n is not equal to infinity
so the sum is not infinite
the sum is always finite
the only difference that a limit makes is that we are asking for what pattern this goes to
as n goes to infinity
the way you asked this made it sound like you couldnt pull the 3 out, because then you would need to be considering an infinite sum, which is undefined
because we are using a limit, the sum is not undefined, it is finite
but without the limit it'd be undefined?
you know I have to wait for your response right?
you can afford to type faster
its been 40 minutes already
i know i just try to solve it but i dont rly know
ok
finite or infinite n?
finite
this works for finite products, right
yes
now
look at this
finite or infinite terms?
the limit is cut off
quick yes or no for me
infinite?
not correct
n is finite
there are exactly n terms
the first term is (1 + 1/n)^3, the last term is (1 + n/n)^3
but if n is infinite?
n is never infinite
the purpose of a limit is to avoid infinity by describing it in a very particular way
at all times, n is finite
ok
ok yes
there are n terms, a finite number of terms
but how would you use this for n terms
now go use this on the finite product
(abcde..n)^3=a^3 etc ..n^3?
yea nino
these are basic exponent laws
are you expecting something strange?
we're still working with finite terms
no its just like a lot of terms
would having a lot of terms change the rule?
nope
so having a lot of terms doesnt change the rule
look how quickly we're finding and fixing the sources of confusion here
we're on good pace, now go try the n-term version of this on the finite terms
theres a quick way you can type the math
go to https://desmos.com/calculator and type in what you want
then copy the line of math and paste it here
thats latex, thats the language desmos and the discord bot texit uses
dont u use some text thing to do it faster
to get texit to "render" or "display" this latex code, you type ,, before it
,,a^{3}b^{3}c^{3}d^{3}e^{3}...n^{3}
ah
mtt
see here it rendered the stuff right, it should look similar to desmos's version
desmos displays things slightly differently but the font should otherwise be the same
wdym by this
this has a lot of terms ,,\left(a+b\right)^{3}\left(c+d\right)^{3}
,,\left(a+b\right)^{3}\left(c+d\right)^{3}
nino
strange how youre seeing that, I dont see the red diamond thing anymore
oh wait they hid it lol
maybe its like referring to it like a ship or a car
i guess
keep in mind you can place anything here in place of a
that includes something like (1 + 1/n)
a = (1 + 1/n)
b = (1 + 2/n)
etc.
yea I didnt want to spoil it but there it is
yes you do it like this
then theres only one ^3 that you use ln(x^3) = 3 ln(x) on
right
its the same thing I showed earlier with ln(x^3 y^3) = ln((xy)^3) = 3 ln(xy)
yes
,,\frac{3}{n}\ln\left(\left(1+\frac{1}{n}\right)...\left(1+\frac{n}{n}\right)\right)
nino
that would pretty much just be 1 inside right
after applying the limit
or 2 actually
try not to take a guess on what it is for now
its going to be hard to predict
alr keep in mind they want you to write this as a riemann sum
now are you familiar with those
mildly
in short, you have that:
will the inside of ln be the riemman sum
can i turn it into a sum
what idea do you have
as before,
you have ln(abcde...n)
now this time theres a different logarithm law you can use
what logarithm law turns this into a sum?
oh right
yes
but what im confused about is how to write that as a riemman sum
once you have it as a sum of logs
write down the sum first
ln(1+1/n)+..ln(1+n/n)
alr
so now we have:
now a riemann sum tells you that an integral can be seen as the limit of a sum
this would be called a "right riemann sum"
the idea is that if you want to integrate something from 0 to 1,
you can draw n rectangles that mostly cover the area you want
these are each thin rectangles with width 1/n, so that putting n of them together looks something like this (this picture has n=4, and youll need to ignore the x-axis for this one)
you can see here that the height of the rectangles has to use the f(x) from y = f(x) to go up to the correct height
so for n rectangles,
you can imagine them going f(1/n), f(2/n), ..., f(n/n)
the heights would then line up with how high the function is at
are integrals always right riemman sums?
they can be left riemann sums too
or middle riemann sums
right riemann sums are just one way of distributing and setting up the rectangles
the integral also doesnt have to always be from 0 to 1
you can see in the image I chose that this one is a right riemann sum with n=4
but its going from 0 to 2 instead
still the same idea
in some cases, theyll tell you the rectangles dont even need to be of equal widths
the general idea is still that, the more rectangles you use, the thinner and better they can be at covering or representing the area under the curve
and so as n -> β, the area of the rectangles -> the area under the curve
for a right riemann sum from 0 to 1,
each rectangle has width 1/n and height f(k/n)
so adding them up gets you:
the term inside the limit is a right riemann sum with n rectangles as said earlier
as n -> β, this area will approach the integral, or the area under the curve
in fact an integral can be defined this way, that is why it is called a "riemann integral"
its just that riemann sums are very hard to work with, so youre better off doing antiderivatives to find their value
what do you think about this so far
i understand the general sense
i dont fully understand how these are equal
you can view the left side as being more like this
each term is the area of a rectangle
n terms for n rectangles, width 1/n, height f(k/n)
heres a picture
this is an example with n = 10
you can see here the areas would be calculated as:
0.1 * f(0.1)
- 0.1 * f(0.2)
- ...
- 0.1 * f(1)
does that calculation make sense
yes
so in general for n rectangles, this is what the area calculation would be
factor out the n and you get this
yup
alr so in short, you have an intuitive reason to believe this now, right
yes
now lets look at this
now to make this slightly easier, Im going to move the 3 out
alr now look at the kind of sum we're adding together
do you think you can guess at what f(x) is here?
ln(1+k/n)
youre close, but remember f(x) is a function of x instead of k/n
ln(1 + what instead)?
x_k?
for example f(x) = x_k^2 doesnt make any sense
we need f(x) = x^2 or something like that instead
Im asking for a function of x here
the reason for that is because choosing the letter x doesnt really matter
f(x) = x^2 and f(y) = y^2 both represent the same function
they represent the act of squaring something
so what I want you to write down is whats being done to the k/n
f(1/n) = ln(1 + 1/n)
f(2/n) = ln(1 + 2/n)
f(3/n) = ln(1 + 3/n)
f(4/n) = ln(1 + 4/n)
f(5/n) = ln(1 + 5/n)
f(x) = ??
@signal solar
each time the same action is being done
yeah im choosing a different letter i meant for representing it as a sum so you'd have the sum of k=1 to n of that times 1/n
youre not supposed to use sum notation without defining the sum first
you need to say that x_k = k/n first
otherwise youre not saying it right
you also need to say what f() is
Hope this helps @signal solar
I don't know how to dumb it down more than that without giving the solution
No no. ...
it sounds like you want to try helping nino from here on out
I need to go do things, cya
cya
Can't you see a pattern here?
I even used bold font

f(x) = (1+x/n)
Let me add more terms
f(x) = ln(1+x)
Yess!! There you go
So now this is equal to which integral?
Recalling this
integral of ln(1+x)*1/x
And f(x) was this, without a 1/x
1/x is dx
yeah i do im just funky on that
ok lets say i have integral of ln(1+x)dx
what do i make the bounds
Yeah you indeed have this (don't forget the 3 though)
the 3 is outside
Read #help-28 message again...
Sure
why does it have to be 0 to 1
Because that's how right Riemann sums work, with this setup
I believe Mtt has already explained it
with riemman sum you can have a to b
I give up, sorry
i mean sure u basically already made the other guy give up too
@void nova
,,3\sum_{k=1}^{n}\left(1+\frac{k}{n}\right)\cdot\left(\frac{1}{n}\right)
nino
this is what i have
forgot the ln
,,3\sum_{k=1}^{n}\ln\left(1+\frac{k}{n}\right)\cdot\left(\frac{1}{n}\right)
nino
the interval should be from 1 to 2
not 0 to 1
it literally goes from (1+ approx 0) to (1+ approx 1)
i dont understand why you would just pent out ur frustration at whatever ur method is and then take charge over the other helper to just also leave urself
I'm tired of this like I actually had a really cool person
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idk where to start here especially since none of these are necessarily integers either
the observation i have is that x, y, z can all be swapped with each other
idk if that makes sense but
add them all together
oh yeah
and then you get (x+y+z)^2 right
well not exactly that
you'd have a constant
yeah ok
you get that=9
yeah ok
thanks
im not used to (a+b+...)^2 im usually used to seeing (a+b)^2 still
idk why
ok let me do that now
so basically all the solutions are x+y+z = 3 or -3
right
Yep
Now you gotta think what to do with that π
One choice is that from this equation, you substitute
yeah
i was thinking this too
you could substitute x as (3-y-z) or (-3-y-z)
Well, try it to see if it works
ok
You need to substitute in 2 of the equations and check if the 3rd one satisfies
The check is important because your values you get might not satisfy the 3rd eq @narrow mica
yeah
this is lit just the first equation π
this q is gonna take me a while but can i simplify this
beyond just doing something like -5 = (y+z)^2 + 2yz - 6(y+z)
so -5 = (y+z-6)(y+z) + 2yz
idk what to do with the 2yz
maybe i made a mistake expanding (3-y-z)^2
idk
Yeah
Not looking so nice
I was going to do a quad on y but i don't think that's so nice
Try making a quadratic of y
yo what u typing in #help-8 ?
Your name suits you so well, freak
That's what you are
Now if you can't help then get out of the channel
wdym
Like, Ay^2 + By + C = 0

