#help-17
1 messages · Page 285 of 1
dat wordt denk te ingewikkeld aangezien je da ni heb gehad
oke dus nu hebben we 4^x²
ja
wat ik altijd doe bij exponentiele functies de afgeleide
eerst gewoon overschijnen
dus ik schrijf 4^x²
ja doe ik ook meestal alleen dit is digitaal dus dan is er iets minder vrijheid over wat ik kan opschrijven
anders zou ik ook [x]' gebruiken
om het op te delen
aaah oke
maar het moet in een stap
dus eerst schrijf je dit op
4^x²
dan doe ik de ln(4)
dus 4^x² * ln(4)
snap je die stap nog?
en daarna doe ik de afgeleide in de macht in dit geval x²
in f(g(x)
dit is geen functie
jawel x^2
ooho zo
en x is 4^x
het was toch altijd zo dat
wil je dat ik hem voor je uitschrijf?
die haakjes maken uit?
tering
wacht ik probeer een vb te verzinnen
ja eens je hebt zo'n bot die het netjes kan maar die nsap ik ni
je kan ln(4) nog omschrijven naar ln(2²)=2ln(2)
waarom wordt die u^x
hahaha
maar maakt niet uit voor dit
waarom wordt die 4^x^2
ln(4)*4^x^2
en niet
ln(4) * 4^x
het hoort toch alleen dat binnenste te zijn
of is dat omdat het niet (4^x)^2 is
h'(x)=f'(g(x)) * g'(x) dus de afgeleide van f'(x) met g(x) erin dus afgeleide van 4^x maar dan op de x zit x²
maar wat ik dus altijd zo doen met exponentiele functies met afgeleides
altijd overnemen
dus e^cos(x) de afgeleide hiervan
bevat sws iets met e^cos(x)
en 4^x de afgeleide bevat altijd iets met 4^x
dus altijd beginnen met overschrijven
tering ik weet die ook niet denk ik
probeer het
ok
ik heb alleen die e nooit gesnapt bij afleiden
die blijft hetzelfde ofzo
e^x is nogsteeds e^x
echt vaag
-sin(x)*e^cos(x)*e^cos(x) is het enigste wat ik kan bedenken
maar dat zal wel fout zijn
functie overschrijven * ln(grondgetal, in dit geval e) dus e^x * ln(e) = e^x * 1 = e^x
hoezo 2x de e^cos(x)?
oh ok dat is wel logisch
wat is jouw reden daarachter?
omdat je ketting regel doet dus een keer om e^cos(x) te differentieren en 1 keer als bijproduct van cos(x) te differentieren als f(x)
maar miss niet dan
de ketting regel is die -sin(x)
nou wat ik dus doe bij exponentiele
is dus gewoon het volgende
e^cos(x) afgeleide : eerst overschrijven, dus e^cos(x) keer ln(grondtal) dus ln(e) * afgeleide in de exponent dus -sin(x)
dus dit wordt e^cos(x) * -sin(x) (ln(e)) is 1
ik zat wel in de buurt
ik denk dat ik dit snap
ik denk dat ike r nu nog een zou kunnen
met iets in exponent
oh shit ln was iets met delen vgm ik weet niet of ik die nog kan hahaaha
ok ik ga proberen
2^ln(x^3+x^2) * ln(2) * (1/(x^3+x^2)) denk ik
ben alleen niet helemaal zeker van ln(x^3+x^2) gedifferentieerd
eerste deel is indd goed
je vergeet 1 ding
nog
want nu is het niet h(x)=f(g(x)) maar nu heb je
l(x)=f(g(h(x)))
aangezien in de ln ook een functie zit
damn ik heb dat ln goed gedaan/
jup
dacht echt dat ik dat vergeten was hahaa
1e jaar hbo
krijg je veel wiskunde op je studie?
redelijk wat volgensmij
maar vooral lineare algebra
maar nog niet
dit is zegmaar voorbereidend
hahaha succes :p
ik ben goed met vectoren tho
ja weet ni hoe diep ze er op in gaan op hbo
er is trouwens nog een handig trucje als je differentieren echt lastig vindt
dat is differentieren door gebruik te maken van de ln
nou normaal heb ik er geen problemen mee maar het is nogal een tijdje geleden
aaah oke
en ik moet nu in hele korte tijd
compleet vwo wiskunde doen
dus het blijft moeilijk hangen
dalijk dus lekker integralen enzo ook
dan moet je extra goed differentieren
ik weet
dus vooral goed je differentieren trainen
maar vgm gaat het niet heel diep in op integralen
ik vind gewoon al die regels zo kut
Aaah dat scheelt
succes met lineair algebra :p
lol
gewoon veel oefenen en dan lukt het je sws
heb hier bijvoorbeeld totaal geen moeite mee
kijk das top
het is gewoon kut dat het in een keer moet in deze oefeningen
je kan zegmaar niet ding voor ding differentieren en dan [x]' erin zetten
nee maar dat gaat wel wennen
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how did they get (4x^3 - 5x)^3
on the denominator
the u^-3 becomes u^3 in the denominator, and then you replace u with 4x^3-5x because that's what we originally said it is
also i dont get when its dy/du or du/dx or dx/du
oh
that's basically chain rule
dy/dx = dy/du * du/dx
what does dy/du mean
like whenever i see smt like that dx is on the top
its the derivative of y with respect to u
like instead when you do u = 4x³-5x then y = (4x³-5x)^-2 becomes y = u^-2
and dy/du means you differentiate y = u^-2 with respect to u first (the outer function) and afterwards multiply by the derivative of u (inner function) which is a function of x
im kind of confused
why cant it be dy/dx
@bitter pilot
oh
dy/dx is the gradient thingy
but why can the other one be du/dx
but y cant be dy/dx
you basically differentiate y not directly with respect to x because that's kinda meh, how would u do that other than trying to expand or simplify (4x³-5x)^(-2)
so the idea is to cover the complicated thing for a moment and call it u for example
so y = u^(-2) now
that is now easy to differentiate
so it becomes dy/du = -2u^(-3)
now if you want to get dy/dx
wait did they substitute u with 4x^3-5x
yes
basically
like how do you expand and simplify that in the first place
so you try to rather think of your current function as a composite function
tbh my school hasnt taught me function notation yet
so weird
bcoz i need it now
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Can anyone help me, please?
In particular, I don't think it is solvable with the classical methods
Because it's neither linear nor separable.
And even if I wanted to make a substitution, I can't think of which one
maybe you can think of it as a bernoulli differential equation
no nvm
maybe polar substitution?
I've never done Riccati actually
Even if I understood this I don't think my professor wants me to use that
But true, I don't see other ways to do it
i sent it because that person also asked for a method with classical tools and there might be a hint
But how can I obtain this crazy thing? 😅 I've never seen these "J" functions
@civic otter Has your question been resolved?
Those j functions are called bessel functions
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how do i differentiate this my solution was (x-1)^2/2rootx + 2rootx(x-1)
✅
Your marking scheme not this is the correct answer?
this is the answer in the ms
hello ?
<@&286206848099549185>
solved it
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I think I can solve this but im just stuck on one thing
I know when I convert it into the form with u and du, when integrating I need to also do something with the limits of integration, no?
yes
I dont remember specifically what I have to do
if you dont want to resubstitute in the end you need to change the bounds
Do you know what to substitute though?
if you have a substitution u = u(x) then you simply do u_1 = u(x_1) and u_2 = u(x_2)
if x_1 was the lower bound then u_1 becomes the new lower bound, and if x_2 was the upper bound then u_2 becomes the new upper bound
So here u = sqrt(x)+4, so my new bounds become
sqrt(1)+4 = 5
sqrt(0)+4 = 4
Right?
Hmm I got a negative number which cant be right, unless I made a mistake somewhere else...
Is this bit right at least?
sqrt(0)+4 = 4
can u show you work
integrand is positive so you should be get positive result
u = sqrt(x) + 4
du = 1/2sqrt(x) dx
how did you solve for sqrt(x)
yikes
it's not really wrong but very complicated
u = sqrt(x) + 4
just move the 4 to the left
besides that you'd introduce with your method unnecessary absolute values
Ah yeah I didnt notice it was square root x I couldve just subbed in directly
yea
But yeah I got this
(2u-8)/u^4
2/u^3 - 8/u^4
2u^(-3) - 8u^(-4)
integrates to
-1/u^(2) + 8/3u^(3)
Yepppp that gave me the right answer
,w (-1/5^2 + 8/(3(5^3)) - (-1/4^2 + 8/(3(4^3))
Noice
seems you messed up a sign before
I messed up a few things 🥲
But my method was right thats the most important I guess
Thank you!!
❤️
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how do i even start this?
maybe is it finding if f_r,\theta = f_r * f_theta ?
We know x^2 + y^2 = r^2
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I’ve been trying and k can’t seem to remember how to find the equation
$y = a(x - h)^2 + k$
King Leo
vertex: $(h, k)$
King Leo
I’ve gotten to 5=a(0-3)^2-4
how did you get - 3 and -4
I got 3 from the y axis and don’t know how I got -4, I think it should be +5 instead of -4
can you first label the vertex shown, and write its coordinate as an ordered pair
i think youre getting confused
V(-1,3)
so what are h and k
-1 and 3?
now can you apply $h = -1$ and $k = 3$ to $$y = a(x - h)^2 + k$$
King Leo
I’ll try that right now
Would it turn to a positive 1?
Would it be y=a(x+1)^2 + 3
now pick any non-vertex point, plug it into your vertex-form parabola, and solve for a
what is (-2 + 1)^2
@simple kraken Has your question been resolved?
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I cannot figure out how to find f with like 3 variables
@heady timber Has your question been resolved?
<@&286206848099549185>
I've not done this in a while tbh.
Isn't the wave speed something like $\frac{\omega}{k}?$
Azyrashacorki
Where your function is expressed as $y = A \sin(kx - \omega t)$
Azyrashacorki
Then all you really need is to solve for $f$ in $\frac{\omega}{k} = 36$
Azyrashacorki
thank you
can you tell me what omega is ?
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am i plugging in -1,4,9 into T(x1,x2)
..
You must create a system of equations
What is the expression of $T(x_1,x_2)$? And what is it equal to according to question b) ?
ss
then, you will have a system
ss
??
this is grade 11 math btw
that is not how this server works
im trying too lol hold up
is this the expression
and is it equal to -1,4,9
yes so how can we find x_1 and x_2
That's not possible
what
its [
\begin{pmatrix} 1 & -2 \ -1 & 3 \ 3 & -2 \end{pmatrix}
\begin{pmatrix} x_1 \ x_2 \end{pmatrix}
= \begin{pmatrix} -1 \ 4 \ 9 \end{pmatrix}
]
ss
write it like a system of 2 equations
oh yeah i added but why is the person saying what i wrote isnt possible
The matrix with x_1 and x_2 cannot multiply with the matrix with -1, 4 and 9
Yes
but isnt this matrix only with x1 and x2
how am i supposed to make it so i can multiply it with -1,4,9
you can have a 3rd line with 0 on it
[
\begin{pmatrix} x_1 \ x_2 \ 0 \end{pmatrix}
]
Yup
do i just plug those numbers back into the equation now
and should i write the matrix out like this now
@inland flower Has your question been resolved?
@inland flower Has your question been resolved?
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This looks like a test
whats your question??
@thorn spindle Has your question been resolved?
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someone explain how to answer this please
Please don't occupy multiple help channels.
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Can somebody tell me if I'm doing this correctly? I'm having trouble with it
Sorry
No biggie, but in the future, its faster if you ,rotate your own images
I didn't even know that was a thing TBF
But yea I'm struggling with this
Any advice?
You got it right, and you used proper methods
Writing 0/0 on your paper is a BIG no-no
This statement is unneeded, because youre evaluating the limit x -> -5, not the value x = -5
These are class notes and he does the whole 0/0 (needs more work) thing
Thats why i did it
Should i speak with my professor about it just in case?
Are you in usa?
And are you taking AP calculus AB
Isn't the limit x--> -5?
This is college 131
Math 131
Calc with geometry
Usa
Edited ✅
Ok, i'm still pretty sure that you should avoid 0/0
So would I be correct or wrong about writing that part specifically?
No issue and I appreciate you letting me know. He was probably just writing it to show that we need to have it in our heads that it "needs more work"
Instead, you should write:
$$\lim_{x \to -5} \qty(x^2 + 3x - 10) = 0$$
$$\lim_{x \to -5} \qty(x^3 + 11x^2 + 30x) = 0$$
$$\text{Indeterminate Form}$$
King Leo
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I have a specific question about this problem
so basically I have a model where red dots can only connect to blue dots. And this problem is in the context of axioms of betweenness and incidence by the way
Why does line r1q (q being r2qb1) not intersect pr2
I know its not suppoed to because of my professor saying so but him re explaining it to me didn't make sense
@viral galleon Has your question been resolved?
<@&286206848099549185>
@viral galleon Has your question been resolved?
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My teacher told me to use the pythagorean theorem to solve this but I dont know which values to insert 🥹
Dont mind the pencil writings
Also idk if what they said is right, after all they are my science teacher.. 🥲
so using the pythag theorem is correct here. we know XN is 10 units right?
and we know the radius is 12?
Yes
draw a line connecting N and Q and what do you notice about that line
oh wait hold on
i misread gimme a sec
Its a hypotenuse 😛
but it's also the radius
Ok jett 🔥🔥
Ig so
How do I apply this, if this is the right theorem
so i actually dont know how to solve this
my bad
u can ping helpers if you'd like
Hello
Shouldn't QX equal QY if both chords are congruent?
I was about to say that, yes.
Then just connect Q and N
You got two sides already, use Pythagoras to find the third i.e QX
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why do I go from 1/2 to 1/4?
U could do the same thing without factoring out right
(1/sqrt(2) x+sqrt(2))(1/sqrt(2) x-sqrt(2)=1/2 x^2 - 1
I guess it’s just cleaner to not have sqrt of 2 in there
2*1/4=1/2
Ah. Not necessarily.
ab+ac=a(b+c)
Sry I still dont understand it.
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stupid question but how do I solve this.. I feel like I'm not understanding the question or I'm missing some key information. The screenshot is translated from finnish to english so it might be a little bit scuffed..
I think it just wants you to subtract the numbers
like for a) you just put sqrt(3)
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i need help
it decreases
🐧
@pliant rose Has your question been resolved?
Prove that $f(x)=\frac{x\left( x^2+3 \right)}{3x^2+1}$ is strictly increasing
TargetVN
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how is my proof here?
@jagged cargo Has your question been resolved?
yeah its fine
also
this is a special case of the lemma i got you to prove before
with the exercise you gave up on 
wait rlly?
yes
a basis of F is any non-zero number, so here you can take phi(u)
and u will be a preimage
oh i see
X = span{u}
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Hello
hey crazy
,rccw
pascal
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Hello
i am unable to reach an answer
not in options
please ping me
<@&286206848099549185>
@fluid flare Has your question been resolved?
<@&286206848099549185>
hello
hello
@fluid flare still need help?
yes
What have you tried?
I constructed AE
then got BOA+COD=135
so BOC 90
but it is wrong
and i am unable to find another solution
I think 90 is correct too
My way is draw OM
M is midpoint of AD
CDO congruent to MDO
Therefore DOC + AOB = 135
RHS
Also how can i get better at geometry
this question took me way too long
any suggestions
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Npp
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is thiis being done right and if it is im stuck now idk what the next step is
how did you get rid of the 2 in the last row
0020 -> 0000
up before that it looks good
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divided r3 by 2.. is dat allowed
.reopen
oh wait
yeah brain wasnt braining i did that last night
i just realized
thanks
u r welcome 
x3 = 0
x1 -4x2 -5x4 = 0
x2 + 3x4 = 0
would that be the final answer
no you need to find a basis
whats that
he means you need to determine the solution
since x_3 = 0 you can put that into equation 2 and then you will notice you have one free variable
- x1 = 4x2 + 5x4
- x2 = -3x4
- x3 = 0
1.1) x1 = 4(-3x4) + 5x4
1.2) x1 = -12x4 + 5x4
1.3) x1 = -7x4
2) x2 = -3x4
3) x3 = 0
ohh ok
(x1,x2,x3,x4) = (-7x4, -3x4, 0, x4)
(x1,x2,x3,x4) = x4(-7,-3,0,1)
x4 ∈ R, x4 is free variable
@inland flower Has your question been resolved?
where did the x4 come from in the first (x1,x2,x3,x4)=
ik the second one u took out x4 as the common factor right?...
I dont know if its easy to explain but
we know
- x1 = -7x4
- x2 = -3x4
- x3 = 0
since x4 is free, x4 = t
x1 = -7t
x2 = -3t
x3 = 0
x4 = t
t ∈ R
maybe I am not making things more clear
oh so just the fact that we know that x4 is a free variable
x2 and x1 are constrainted to the value of x4
and x4 is constrainted to t which is a real number
maybe I am making things more confusing, I am sorry
i think i understand
so when its saying to find all the vectors
do i turn
x1 = -7t
x2 = -3t
x3 = 0
x4 = t
into a vector
like
...
but most likely we messed up in the row reduction step because
,w Nullspace {{1,-4,7,-5},{0,1,-4,3},{2,-6,6,4}}
wolfram Is giving span{(9,4,1,0)}
well go through the row reduction and see where u messed up
but you can check with wolfram
after you divide row 3 by 2
you confused the 3 with a 5
thats my 2 cents, maybe I am wrong haha
@inland flower
yea
i did see my own handwriting as a 5
damn
😭
thats crazy
how did i go that wrong
all i gotta do now is subtract r3-r2
wait
yeah
do i do the same plugging in thing i did before
this not seeming right now
@inland flower Has your question been resolved?
still here?
yeah
whats the issue any updates
I went back and redid my matrix because it was wrong and now i have the last row 0000 and i made an equation but im not sure what to do next
because when i first did it i just had x3= 0 so i plugged than in and went from that
but now the second equation is long
and i made x2=4xx3-3x4 and tried plugging it in but idk if it seems right
so idk what the next step is
ok yes
ok so you got basically two equations
it will have two free variables if you solve for one
so far it's correct you just need to finish
figure x_1
x_2 is already given
and then your solution is of the form
you can write it as a vector
I will write it as a spoiler so you can check up
the problem is that when I checked with wolfram, the nullspace of the matrix A has only one free variable and not 2, maybe there is another misstep in the row reduction
where
i checked as well and it's got two
you put a 4 instead -4
the x1 -9x3 7x4? = 0
x_1 will be replaced with 9x_3 - 7x_4
do i plug that back in
yes you replace x_1 with that
your solutions only depend on x_3 and x_4
since they are free variables
i thought i was replacing x1
in here right
here
oh
when you solve a system of equations you can write the solutions in vector form
can i put x2 as 4x3-3x4
yes and you have!
how do i get x3 and x4
😄
or do i already have that
yep

Now if you want
you can but you dont have to replace x_3 and x_4 with variables like s and t
to make it look nicer
like this
can pick either of these two
this set contains all possible solutions of your system 
so writing either one of these ways
would be right?
yes
it means for every vector in R^4 it must have the form of this vector inside
because then it is a solution 😄
expanding it like in the right can give you an idea of how it looks
and yea it's a plane because it's two independent vectors and they always span a plane
and that plane is in 4dimensional space
kinda hard to visualize
this stuff feels like it should be easy but im struggling🥲
my two other questions are like
half started
cuz i got stuck
like
for this question
are the numbers in green being plugged back into the equations
are you trying to write down the equations?
oh
no
no
no
not atll
else it would be
T(-1,4,9)
this seems like the first question but the vector is already given to us
so working backwards or sum
?
so whats the first step i take
to solve T(x) = (-1,4,9)?
yes splendid
next step is you can actually multiply the matrix
and derive the system
and the equations
does it make sense?
i think so
I realized a little mistake you did
[x_1, x_2] just
3 components then the matrix multiplication is invalid
(3x2) (2x1) -> (3x1)
so let me fix something
ok
can you write down the equations?
like x1-2x2 -x1+3x2...
a bit clearer please
the first one you started right
1 * x_1 + (-2) * x_2 + 0 * 0 = -1
x_1 -2x_2 = -1
oh simpler
x_1 - 2x_2 = -1 right
-1x_1 + 3x_2 = 4
3x_1 - 2x_2 = 9
these are our equations
ohh
and we can write them into a matrix!
i do this so thoroughly so you understand 
So we can solve the following
[ \left [ \begin{array}{cc|c} ,1 & -2 & -1 \ -1 & ,3 & ,4 \ 3 & -2 & 9 \end{array} \right ] ]
lemme guess
perform row operations ?
uh does this seem right
and if so when turning it into an equation do i do x1-2_x2=-1 or is it x1-2_x2-x_3=0
last row operation R_3 - 2 is illegal
instead do -2 * R_1 + R_3
and also it's better to utilize the diagonal elements when row reducing
like after R_3 - R_1
do immediately -3R_1 + R_3 to also make the 3 a 0
then move to the entry where -2 was
i gtg for now, i hope you can somehow manage on your own for now, for reference what to do you try to reread how we approached the previous system
and how we wrote down the solution
after i do this
do i equal the equation to 0
and do what i did in the first question
not to 0!
I did put the vertical line for a reason
you equate it to the numbers in the 3rd column
the vertical line means basically what come after the = sign
thanks
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So I have an electron, and the probrability of finding it at n state is:
p_e = (196/(pi^4n^4) ) * sin(pin/2)
Thus the commulative distribution is the sum of the p_e's to N.
Now, how can I find the smallest N such that the added probrabilities are greater than 0.999?
So how can I find the minimum amount of probrabilities, added from n=1, so that they add up to being greater than 0.999?
Like I could just brute force, trial and error this but it seems, unscientific
This probrability distribution is multinomial (to pretty much infinity) so it's hard to work around
Your probability distribution goes negative.
Did this a probability distribution or amplitude?
@lyric shadow
it shouldn't, the probrabilities should just be getting exponentially smaller as n increases
also the value for n = 1 is larger than 2
have you tried actually computing these values?
yeah, that's the point, the probrability of finding the electron in higher states decreases exponentially
the only mistake i've made is putting 196 instead of 96
thus p_e = (96/(pi^4n^4) ) sin(pi*n/2) actually
if it's a probability mass function, then the probabilities should be strictly between 0 and 1
ok, that brings the n=1 case to below 1. This is progress
with 96 nwo as 196 it is so
did you forget to square ur coefficients?
oh fck i made another type sorry
the sin is squared
p_e = (196/(pi^4n^4) ) sin(pi*n/2)^2
so sorry
yh lol that's what i suspected
nw
anyway if this is in the context of some problem sheet question, probably just compute the first few values
Honestly, I would just compute by hand as well
is there no other way?
there are only a few
it decays like 1/n^4
like what if it became greater than 0.999 at N=43?
and the alternatives to bounding the area are, like, integration estimates.
so basically you have very fast decay so it should hit 0.999 very quickly
It will become greater than 0.999 in like n=5 or n=7, and you only need to test the odds.
if this isn't like as a problem sheet question and there's a chance that N might be very high, you might want to bound N to get some approximate value for N
or find asymptotics
i mean effectively, you want to understand the sum of 1/n^4
there's no closed form formula for that, but the Riemann zeta function is very well understood
(although if ur doing QM i don't think you need to know asymptotics for sum 1/n^4 lol)
yeah, it is part of a problem sheet but it's like 6 marks for the question which seems like a lot for just a brute force question
i guess the only thing that could give extra marks is just saying that it decays very fast due to 1/n^4
but i was also just curious about how you could do it if the value for N was actually really large
thanks
I mean, honestly I'd just write a computer program to do it in that case.
and if it's titanically large, I'd consider thinking of smarter ways to approach it, such as with an integral approximation.
yeah, that's a good idea
thanks again
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i want help double checking this answer, i think it might be DNE
as far as i can tell this limit does exist. show your work for how you got DNE?
hmm okay, that was my initial answer too before i second guessed and thought it was dne
my first answer was -5/9
show work for that one too?
won't hurt to check for arithmetic errors and the like
sorry took a bit, i had to rewrite since i erased it
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hey
So im trying to understand how is d the correct answer
how is 3ln2/ ln4+5 equal to 3ln2/ln2+ln3+ln5, or maybe i have understood this wrong
But how do i actually solve this problem?
;(
Sorry i should have been more clear, first pic is the problem
second is the EXAM answer
3rd is my work
I can tell
But still
yeaah i dont understand what do i do wrong
The crazy part is that the answer key is incorrect
Let me see if I can work it out.
a=ln5, b=ln10, T=ln8/ln30
So...
Legit there are no factors of 3 here. I don't think this is solvable using regular methods.
Valiant effort by you, though.
Damn, could that 30 be a typo from 20?
Maybe it's vice versa, I don't know.
Well, we can add in a ln3 if we want to.
I was just thinking we were only allowed to express it in a and b, no constants besides the coefficients.
You know what I mean?
Hmm not rlly
Im just preparing for an exam idk a lot of math which is wild cause
this is from the university website
Wild because it might be a typo
i was thinking im just bad tho
probably comes from the 8 being 2^3 but havent calculated anything
Probably. Anyways, if you want to solve it by adding an ln3, go for it.
Otherwise, the exam key here does not match with the question
ln2 = b - a
I don't think you should. I'm only saying this if you want to do it for fun.
ooh
Since it's just an invalid anyways.
yes