#help-27
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I'm thinking for r
it looks like
2x = x^12
not sure how to solve for x though
wait nvm
.solved
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over reals it would be, but here you're supposed to find all solutions (i.e. solve it over complex numbers)
in complex numbers, an equation has as many solutions as its degree
is it the magnitude that's supposed to become -128?
in this case 7
nope
wait actually
is there a version with exponentials then may i see it
i see i get it now thank you
it follows from this, yeah
bring it to polar form and then find the roots according to this formula
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✅ Original question: #help-27 message
hey @scarlet sequoia thanks for helping out on the last question. Think you can help me on this one?
Hint: geometric series
curious, is this possible without a calculator or not
also, when they say sum = 0, how is that possible if it's a complex number
oh wait
im guessing it can be something like e^(j(2pi)) + e^(j(pi)) could be a way
very simple way tho
thanks brodie
you can get an exact form w/o, yeah
this funnily reduces to a really simple equation
all i did was take out e^j(.2026pi)
my friend showed me how to do it
he told me something about geometric series though
$\sum_{k=0}^Nr^k=\frac{1-r^{N+1}}{1-r}$
;(
this is finite, ones covered in calc are infinite
wait do you see an image anywhere
is texit down 
that's for infinite as well
then he did stuff with the exponent
i can show you a quick proof
what proof
of this formula
ok
sorry I'mma go take a nap soon but i'll just show you before that
$S=1+r+\ldots +r^N$\
$rS=r+r^2+\ldots +r^{N+1}$\
$S-rS=1+r+\ldots +r^N-(r+r^2+\ldots +r^{N+1})=1-r^{N+1}$\
$S(1-r)=1-r^{N+1}$\
$S=\frac{1-r^{N+1}}{1-r}$
;(
thank you
wait tell me if im right im curious @sharp obsidian
it dosent say at all it just gives an average
i thought it was the right and middle collum
from what i see
if you were to put the first 3 squares' red dots in one single square, then that single square will be filled with red dots
wait ngl
this is a bit hard it could be all middle horizontal red dots filled out
no idea tho
i see where your coming from icl
why do you think that
going back
if you were to put the first 3 squares' red dots in one single square, then that single square will be filled with red dots
wait
actually
it has to be this
wait no
naw man i give up bro
its hsrd isnt it
i'll ask everyone on my dorm floor later tho it's a sick question
!occupied
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bro what
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thank you guys for the help
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oh i get it my bad
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I understand the formula 911 + 2[911(0.80)+911(0.80)^2....]
And understand this series converges but
the answer is 8199 and I dont understand how to get that?
I did 911 +2 (911/ 1- (0.80))
<@&286206848099549185>
Note that the geometric series we are doing is 911(0.80)+911(0.80)^2....
The first term of that series is not exactly 911
So what would it be?
The first term would actually be 911*0.80 (since we are concerned with 911(0.80)+911(0.80)^2....)
Indeed
OH yeah
I thought the "First Term" had to be a single isolated phrase" i understand thx
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can someone solve this
riemann
familiarize yourself with those
!show
Show your work, and if possible, explain where you are stuck.
you did pi/4 * 5 = 5pi/2
oh you said ignore that
oh you messed up 1 / [1/2 ^ (-5)]
the magnitude should be 6^3 / 2^5
magnitude?
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is this a identity
yes
you can use the cos(a+b) and sin(a+b) identities on the right hand side to confirm
(they're the only trig identities i bother memorizing)
on the right hand side?
if possible could u show pls
Bungo
so
$$\cos(\theta - \pi/2) = \cos(\theta) \cos(\pi/2) + \sin(\theta)\sin(\pi/2) = \cos(\theta) \cdot 0 + \sin(\theta) \cdot 1 = \sin(\theta)$$
Bungo
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laplace transform of $ln(1 + x)/x$
Einstens Skibidy Rizller
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
I think you can assume that theres a heaviside there.
Assuming you use the one-sided version
If it is the one-sided laplace transform you dont need a heaviside
I think in most cases the time-shift identity is taught while having heaviside present, or thats what my limited experience tells me
You also will prob need the $\mathcal L {\frac1tf(t)}$ identity
,,\lm \LL \left{ \4{g(x)}x \right}(s) = \int_s^\infty G(u) \dd u
That
Although the resulting integral contains the Exponential Integral
You won't be able to get a closed form solution
,w Laplace transform log(1+x)/x
!xy
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.
integral is $\int_{0}^{\infty}\sin\left(x\right)\frac{\ln\left(1+x\right)}{x}dx$
Einstens Skibidy Rizller
what does it look like
,w integral of sinx ln(1+x)/x
Seems there isn't even a closed form
equivalent form \begin{align*} I&=\int_0^{\infty}\frac{e^{-x}\tan^{-1}(x)}{x} dx \
I &= \int_1^{\infty} \frac{\text{Ci}(x)\sin(x)+\left(\frac{\pi}{2}-\text{Si}(x)\right)\cos(x)}{x}\ dx \
&=-\left(\frac{\pi}{2}-\text{Si}(1)\right)\text{Ci}(1)+2\int_1^{\infty}\frac{\text{Ci}(x)\sin(x)}{x}\ dx \end{align*}
Pretty close
https://math.stackexchange.com/questions/2733923/evaluate-int-0-infty-frac-ln-x-sin-xxdx
Einstens Skibidy Rizller
that one is ilt of ln(x)/x
saw it before
Ok buddy
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How can you check if this graph is planar
Yk the colouring method?
arachi
Oh yes
And if there exists a subgraph that is isomorphic to K5 or K3,3 then it is not planar
Yeah you can use Kuratowski's theorem. I think that tangle is probably a K_3,3 subdivision
so I use edge operations?
I think try to trace a Hamiltonian cycle and consider the remaining untouched chords
What are edge operations to be clear
When you add 1 vertex and 2 edges or leave out 1 vertex and 2 edges
If you get something that is isomorphic to K_5 or K_3,3 then the graph is not planar
after you do edge operations
Yeah
Thats basically what i meant earlier
Your thing is isomorphic to an M4 Möbius ladder if im not mistaken
what is a mobius ladder
In graph theory, the Möbius ladder Mn, for even numbers n, is formed from an n-cycle by adding edges (called "rungs") connecting opposite pairs of vertices in the cycle. It is a cubic, circulant graph, so-named because (with the exception of M6 (the utility graph K3,3), Mn has exactly n/2 four-cycles which link together by their shared edges to...
ijo Sani
That specific tangle is M_4 i think
-# the example in the wikipedia sidebar annotates the image above as M_16, so i gather that the naming convention is total number of vertices
I found a subgraph isomorphic to K_3,3
dont mind the arrows
This is $K_{3,3}$
arachi
because it's bipartite
good! is your question answered / how do you answer your question?
I just wanna know what I have to do in general
if I get any graph how should I check if it's planar
this is usually the way to go to show it is nonplanar
to show a planar just find an embedding
Alr
New question
so here they want me to check eulers theorem
this
$v-e+f=2$
arachi
I counted 17 vertices, 32 edges and 21 plains
but that doesnt add up to 2
nvm I counted wrong lmao
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i understood the telescopic sum for this qn but the answer i calculated was a bit far off
Those two values look to be about π/2 apart
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there were in fact two individual telescopic series to be accounted for
man these are weird
If you expand it out manually the last two terms will not telescope out
so at the end of it all, there are two copies of arctan(∞)
$\lim_{N\to\infty}\left(-\arctan\left(\frac{1}{2}\right)+\left(\text{telescoping stuff...}\right)+\arctan\left(\left(\frac{N+1}{\sqrt{2}}\right)^{2}\right)-\arctan\left(\left(\frac{N}{\sqrt{2}}\right)^{2}\right)\right)$
Roy
etc
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Factor z² out of the first two terms
Can you see a common factor here that may be factored out?
how do u even know to start this
is it just intuition
Because this idea occurs a lot in factorization and my pattern recognition spotted it
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hi, does anyone know where i went wrong
4*9=13? 🤔
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can someone take me through b)? I'm not quite sure how to do it
There should be worked examples in the textbook which demonstrate how to do these kinds of questions. Either way, have you started by writing RHS in polar form?
yeah, it does go through it but im like lowkey lost
Yeah
That looks good, do you know how to continue?
no i dont unfortunately
Equate the moduli
wait what
should be no problem to write down
3cis(pi/6)
3cis(5pi/6)
3cis(-3pi/6)?
oh wait yea
it doesn't really request your answer be in polar or cartesian so leaving it in polar should be fine
wait thats the answer?
z = this
yep
ohh
you just need to plot them on the Argand diagram now
do i have to
link those
to the center
or draw a circle??
like this is mine vs the answrers
the circle?
yes
@charred eagle Has your question been resolved?
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Does this look good?
n is taken from 1 to infty (the textbook omits in bracket notation)
looks right
looks fine but remember you are given epsilon in these problems
the convergence bit is that GIVEN any epsilon > 0 you can find an n
also nitpicky but $N=\frac{1}{\epsilon} + 1$ does not always mean $N \in \mathbb{Z}$
Mirror
that's bs 😒 I guess I should have done ceil(1/eps) then
that works too!
again your argument is SPOT ON you are just going to get dinged on a technicality because you are given an arbitrary e > 0
Originally I was gonna say take eps in R+ but then I was like I guess I can just skip to N = (expression in terms of epsilon), I'll edit to include it 👍
ye i mean "given epsilon in R+, set N=ceil(1/epsilon)"
Right
is basically the same thing but a prof looking for something to mark will get you every time
almost done rewriting
usually you would just say pick N > 1/ε
Oh you can just let the reader choose their favorite N?
also nice handwriting grandson 
^^ indeed nice handwriting
ye you can let the reader choose their favourite N because all you have to do is show that at least one N exists
you can, the only thing required in the argument is that N > 1/ε anyway
(nb: N > 1/e has infinitely many solutions for all nonzero e)
Well that makes my life easier than this floor(1/e + 1) nonsense
This I can do
So we have nonconstructive existence of such N for every eps
Does it look good :)
oop didn't get a notification
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hi
hello
I need help on how to rotate an object
Asking the actual question right away is more likely to get responses.
Asking "Can I ask...?" or "Does anyone know about...?" doesn't give people enough information to decide whether they can help, and answering can feel like a promise to help with the actual question, which they might find themselves unable to.
no not really
!xy
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.
yes we need more context
we were given this question;
find the coordinates of the vertices of the image a parallelogram who's vertices are A(3,5), B (7,5), C (5,0), D (1,0) when rotated about the origin through -90°
with no guide and I have already plotted the points but I do not understand how to rotate the image
try rotating just one vertex at a time
think about how to do that with individual pts
the amount of rotation is -90° so it's going to result in nice and clean values
(it means 90° clockwise btw)
thats the thing, our teacher didnt teach us anything about rotation, so basically I dont know how to rotate
how am I supposed to rotate the vertex?
This geometry video tutorial focuses on translations reflections and rotations of geometric figures such as triangles and quadrilaterals. Transformations include horizontal and vertical translations, reflection about a line of symmetry such as the x-axis, y-axis and origin as well as rotating a figure clockwise and counterclockwise by 90 degree...
tysmm
@fair wigeon Has your question been resolved?
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f(x) = 3(2)^(x+2) + 2 and g(x) = -2x + 3
$f \circ g(x)$
Bungo
thoughts about how to start?
this looks like $f^{\circ}$
USS-Enterprise
This is correct
i forgot how to do this one
yeah
recall what composition means
you had to like
$f \circ g(x) = f(g(x))$
Bungo
substitute g into the function f
yeah
so what do you get if you do that?
substitute the expression of g into all the x's which appear in the definition of f
(aka just one x in this case)
just as if you would substitute 7's into those x's if you compute f(7)
Doesn't matter
This is the definition of fog(x)
When it itself is defined is a different story though
nah i just realised cause i have to learn exponential and log
that wouldnt be in an exam for me
And?
Yes, could be of use
I mean I don't know what your exam is going to cover
If you haven't learned logs and exponents then no you don't need to know this obviously
what do u mean by if i have log and exponents
like in a problem and theres an equation of a log and one equation of an exponent?
Huh? Wdym
f(x) is exponential and g(x) is a log right
Well in this case f(x) is an exponential function
Such as f(x) = e^x, and g(x) = ln(x)
You should know what g(f(x)) is
Well..... Of course!! 🙈
yeah
In this case you need to know exponential functions
gotcha so like what will doing the composites do
To be able to work with this
Haven't you been taught those?
like 3 months ago
Then revise your notes...
In short, they combine two processes into one
like you have f(x) and g(x) and u substitute the equation into one right
In this case, instead of first computing g(x) for an x, and then f(that output) you can just compute f(g(x)) for that x
ohh
^ this is all there is to it
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for 7 part b I write f'(x) = (x-alpha)^r g(x). Are you allowed to suppose that g(x) = 1 and then you have that f(x) has r+1 zeros. Does assuming that g(x) = 1 make it less general?
how could you then integrate some general function. You can't know if the integral exists and he hasn't shown how to integrate a product of functions
My idea was the fundamental theorem of algebra idk if you've heard of it
a polynomial of degree d has d complex roots
I am going to assume real since that is how he was talking about the mulltiplicity of zeroes
also for this section he talked about rolle, mean value and cauchy mean value but I dont' see how any of those apply
was part (a) also assigned?
ye
i dont have anything concrete as im figuring this problem out alongside you, but i would suggest examining polynomials multiplicities and how taking the derivative affects them
cause that's what im doing
so it could also be true if we had j(x) = r+1g(x) + (x-alpha)g'(x)
but again that limits what our function can be
note that if you look at (x+3)^3 the root shows up in the first and second derivative
this isn't exactly profound
but just something to notice
f^(k)(x) is of the form (x-a_1)(x-a_2)(x-a_3)...(x-a_r)
where a_i and a_k are not necessarily distinct
what is f^(k)(x)? do you mean f(x)^k?
the kth derivative of f
ok
part b is going the opposite direction of part a right?
so if lose a zero every time you take a derivative what happens when you take the integral?
@robust bobcat Has your question been resolved?
add one zero but that doesn't seem rigorous enough
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is this unimodal, bimodal, or trimodal
genuinely curious to the answer. prof is saying bimodal, others online are saying unimodal
conversation had:
me:
also the sampling distribution of the median is not bimodal -- technically it could be described as unimodal with two noticeable bar heights. one had a very noticeable difference in height than the other, and im pretty sure it was like 2:1 ratio in frequency. but i think in retrospect, it would have been better to just have called it a discrete distribution concentrated at two values.
op of the campuswire:
TA wrote bimodal on the key for takehome but I also thought that it was weird
me:
yeah just saw it haha, they didn't give a reasoning though -- @prof? curious about this now because then it comes to what defines a peak mathematically. like is it just "it showed up visually on the graph and also there's like nothing next to the values" or is there a more mathematical way to define bimodal
the OpenIntro Statistics textbook defines bimodal as "any distribution with two prominent peaks" but what if someone interpreted the graph like this
with this attached
prof:
The point here is that these are not histograms of a sample drawn from a population. IF you treat the graph shown above as the population distribution, then it is bimodal with precisely two peaks. Or you could define it as discrete with precisely two values. The sketches superimposed imply the possibility that there are values that we didn't see but could happen. But if this is not the case, then those sketches aren't correct.
so then i wrote:
then by this logic, is my sampling distribution trimodal? it had values at 540 after all
are we defining peaks as bars we can see on the graph or just values which don't really have anything next to them
the qqplot again for reference
he then writes:
yes, it would be trimodal. But you are right....if you push this logic far, than a discrete uniform distribution on the integers 1:1000 would be millenial-modal or something like that.
and that doesn't seem right.

hello queen
is my prof ragebaiting me
im not sure -- others are saying that it's unimodal online and others say bimodal
hm lol
wahhhh
its okay
i actually dont gaf i cant really see a reason why id have to use a median sampling distribution in my field
in this specific context
just a little annoyed to get docked off points when other people in industry would call this bimodal/unimodal
with a pretty even split
i am trying to find precise definitions of multimodal distribution on the internet and i can't really find any
so yes let's go with your prof is ragebaiting you
i too was trying to find one queen
one such rigorous definition is literally if two values have the highest frequency its bimodal
but by the professor’s logic i can splice a normal distribution in a spot that isn’t at the peak and suddenly i have two peaks
guh

@somber jetty Has your question been resolved?
i love you
you are an amazing bot
so delighted!
@somber jetty Has your question been resolved?
love no it hasnt
you're so beautiful though
i love you bot
what a beautiful mind
you have
@somber jetty Has your question been resolved?
from what I know, one usually defines define modes as distinct concentrations of probability mass... that is, peaks that are distinct from their surroundings.. since the bar at 660 is separated from the bar at 600 by a valley of zeros, it counts as a second mode... I believe that in practice people reserve trimodal for cases with three comparably visible peaks rather than one major pair plus a trace
thank you father
amen layla


amen twin
amen mommy
what the blud
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in this question the overall velocity is constant, which is vo
why in this question is the overall velocity not just 10 ms^-1, rather its just the x-component of the velocity of peg a
i think the slotted link moves at 10 m/s (the huge brown coat hanger shaped one)
and the pegs are connected to the slotted link to be in the same vertical line
so the horizontal component of the pegs are forced to be the same as the slotted link to move along with it
Closed by @green crypt
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anyone can tell me that is this relativity
I dont understand that weird e
@brisk cosmos Has your question been resolved?
ok
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What have you tried
hm i had a question in this, do i need to simplify it after multiplying 2x with the other terms
do you want a picture
There is nothing to simplify after multiplying 2x I think
there will be a bit of simplification to do on each term, but it looks like you already did it
hey again,
but my questions still goes since yesterday that why cant it simplify it
??
Because there is nothing to simplify
All of them are simplified just multiply the two that's all
you've expanded it
so your expression is in expended form already and there's nothing else to expand
ohh, so the question only asks my to expand but not anything else if i am not wrong
but if it was not the question then could i have added or subtracted them?
no, bc they are unlike terms anyway
ok, but if we had other operations like multiplication then could we have done it?
Yes for multiplication you usually operate them
ok, not addition or subtraction, right?
For addition it's only for like terms
Closed by @compact spruce
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Np
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$\frac{\ln(1+x)-x+\frac{x^2}{2}}{x^3}$
Goofy Joe
lim x->0
I've redone the calculations I don't know how many times, random numbers come up
what have you tried
Show your work, and if possible, explain where you are stuck.
what did you get in taylor ?
$\lim_{x\to 0} \frac{\ln(1+x)-x+\frac{x^2}{2}}{x^3}$
Ann
yh after simplifying
I redid the calculation over and over again. Everything superfluous was erased, the useless terms disappeared... in the end, only one thing remained on the sheet.
but it was wrong
like 7/25 or something
...... what did you get with l'hopital
it should be quite straightforward with l'hopital
i dont remember
try it again
ok
hm..
$\frac{\ln(1+x) - x + \frac{x^2}{2}}{x^3}
\frac{(x - \frac{x^2}{2} + \frac{x^3}{3}) - x + \frac{x^2}{2}}{x^3}$
I have a better method
scoob
Yeah this explains it
this simplifies to a good value
i got 0
if i see lhopital more than once skip
its just one l'hopital step
X and x^2/2 gets cancelled out leaving x^3/3 remaining
i get like 1-1/6x=0
then the top and bottom cancel out nicely
ic
I get as far as the derivatives, but then I get some strange stuff and it doesn't match anything... so I don't find it.
it helps to show those strange stuff, I believe.
we have
{ln(1+x) - x + x^2/2 } / {x^3}
can you write/type out the derivative of the numerator, and the derivative of the denominator?
yh lhopital is better here
he threw his work 🥀
(1/(1+x)-1+x/3x^2)
now simplify
we dont like having fractions in the numerator itself
if you multiply numerator and denomiator by the same thing, the value doesnt change
1/3(x+1)
what does this become?
1/3
see? not that complicated
when you do 1 step of l'hopital,
you differentiate the numerator 1 time
you differentiate the denominator 1 time
i know
so you differentiate the denominator, x^3, only 1 time
yes
are you asking why you only needed one round of l'hop in this question?
or why does lhopital work?
yes
call it a coincidence that the question was nicely set
but here we have to consider Δ x?
you mean the
lim x --> 0
thing?
Δ x=x since x->0
infinitesmal x i supose
for l'hopital we dont need to consider infinitesimal
if you're curious on how it works
or why it works
the big idea is that the infinitesimal ∆x on numerator and denominator when differentiating cancel out geometrically
Source: YouTube https://share.google/iZzv3EkKwMdI1Ts1t
Formal derivatives, the epsilon-delta definition, and why L'Hôpital's rule works.Help fund future projects: https://www.patreon.com/3blue1brownAn equally val...
ok
uhhhh not sure what you mean
how i know already that the result is <1
thats the neat part, you dont
you could compute using calculator/otherwise with tiny values
but at first glance of the entire qn, if nothing is telling, you have to attack it first
and after some manipulation/calculation then you can get an idea
but aren't there some kind of demonstration where it is shown that the limit is a certain value?
by demonstration do you mean like a graph? or testing values that get closer and closer to 0?
with the definition of limit
you want to use epsilon delta definition to show that the limit is 1/3?
that is <1
oh, you want to deduce that the limit is <1 without actually solving the limit?
no
I believe that by the nature of epsilon-delta proofs, you are going to find the limit directly rather than deduce a plausible range for the limit.
if that is what the OP meant.
ok
using epsilon delta to show that the limit is <1.... ?
yes
oh god
?
I'm not sure if that kind of question is what an epsilon-delta proof is meant to solve, no?
^
ok
i meeeean you could try
but it wont be a very productive use of epsilon-delta
no
and its going to be much more tedious than it should be
Closed by @viral kernel
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Hi!
im having trouble rigorously finding the value of K in
$\int_{a}^{b} \delta(x)dx = K$ for $ b > a $ ,$b < 0$ or $ a > 0$
Saggitarius
anything i think
its just for an assignment
i believe that it will equal 0 but i have no clue how to show it
,, \lm\int_a^bf(x)\delta(x)\dd x =\e{dcases*}{f(0), &if $0 \in (a,b)$ \ 0, &if $0\notin [a,b]$}
for a < b
this is all you need to use, pretty much
Don't you have a definition
by definition of the dirac delta distribution
for dirac distribution
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Find the last digit of $\floor{(2+\sqrt{3})^{20}}$
lower! <- dum dum
This looks like some binominal type shiii, but the expansion looks nasty 
I think I have a trick involving the conjugate.

try summing the expression with its conjugate.
the recurrence will probably be established through what I said, so consider both Lex's point and my own.
Nvm I figured it out
Use the fact that $a_{n}=(2+\sqrt{3})^{n}+(2-\sqrt{3})^{n}$ is always an integer, and you will obtain a recursion of $a_{n}$ thus a recursion of $a_{n}$ mod 10
Cogwheels of the mind
Yeah I see that
One more question b4 I sleep
This question is from CSP bruhhh
I haven't figured it out
$x^2-7x+1=0$ Let $\alpha$ be a solution of the equation, find the last 2 digits of $\alpha^{2026}+\frac{1}{\alpha^{2026}}$
lower! <- dum dum
Okay so, I establish a recurrence relation
$a_n=7a_{n-1}-a_{n-2}$ with $a_1=7$ and $a_2=47$
lower! <- dum dum
I managed to figured out the last digit, but the second last
I couldn't find the pattern for the second last digit 
You need a_n mod 100
It doesn't seem to follow any pattern to me idk
given that you are working mod 100, if there is a pattern it would have a maximum length of 100 steps.
a1=7
a2=47
a3=322
a4=2207
Yeah if it is 100 steps there's no way
I can find that
working mod 100 means to keep only the last two digits.
Ik
Yeah ik
I found period being 15
you could probably code something quick to help with finding out a pattern... but damn if I'm skilled enough to do so.
No way
, there has to be some other ways to do the problem
yeah getting this remainder stream
i mean its not that arduous so i guess its something
if it's period 15, it's not terribly bad, esp. working mod 100.
No I meant CSP never give a question that require a calculator
This is doable by hand. Just unnecessary
And also a_16 is damn large bruh
Why you don’t mod 100
I can, ofc, but I still have to find a1-a16,17
CSP shit
f(x_1,…,x_n) mod m equals f(x_1 mod m, … , x_n mod m) for polynomial f
you don't need a calculator!
if you ever get to a point where you are using a number that's 3 digits or more, you know something has gone wrong.
Yeah. Straightforward calculation, don’t seem to be hard to obtain at all.
Damn
for example, consider your a_4.
I meant this's bad, so much calculation, I didn't expect CSP to give me this question
Why you kept saying so much calculation
Cuz that's too much for me bruh
your a_4 has four digits, and your a_3 has three digits.
your a_3 should not have three digits after modding by 100, so a_4 should not exceed 999.
7x-y for two digits x and y and read its last two digits aren’t much calculation at all
You could do it a bit faster by doing mod 4 and mod 25 ig
though I would understand the slight inconvenience of having to hammer 16 terms.
7x-y, for two two-digits numbers x and y, and as soon as you have calculated the last two digits you can stop.
okay this problem sucks, for me at least thanks y'all
To me it's really inconvenient, because I always avoid doing calculations, I meant I usually only do one ore twice/ problem
Idk ig it's just me
I'm a bit bad at doing calculation now tbh
We all are
welcome to computational hell.
Better at math worse at calculation
I meant doing them by hand would take me 6-10 min
But we all have to do some calculations at some point
Closed by @azure parrot
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Oh that's why I hate cases work in Combinatorics 🥀
Mod 25 the period is much better btw (only 5)
so doing mod 25 and mod 4 is prolly quicker (then CRT to combine)
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Just dont get this topic
close one of your channels
Can u help?
tf is this question
I dont get it
That aint even a grammatically correct sentence
Or am i trippin
Idk
Idk
play it?
Im guessing the video explains how to do it?
No its not clear to me tbh
heads-up: you aren't showing the full diagram.
Oh mb
also how are you supposed to use ruler on screen
I presume OP is to construct it on paper and send an image of their work.
K will do in a sec
This one I dont get it
Im on that
please do not repeatedly ping me.
Mb ill turn off my ping
Didnt mean to do that
<@&286206848099549185>
?
I didnt get it
what do you think , point equidistant from B and A are at equal distances from both
Is it 3,4
Sorry the other way around
?
that is the midpoint you need all points that are equidistant,
not only one point
Ahh
Mb
do you know distance formula
Time*speed?
this
But isnt the question singular?
distance b/w two points
Im in year 9 so I dont really get it tbh
it asks to find locus of points
@fresh bane Has your question been resolved?
hm..
have you learnt the distance formula
This geometry video tutorial provides a basic introduction into how to use the distance formula to calculate the distance between two points. It also explains how to solve word problems such as how to calculate the area of a circle given the coordinates of the center and a point on the circle using the distance formula. This geometry video tut...
watch this
this is used to find distance b/w twpo points A(x1,y1) and B(x2,y2)
you know coordinates of A and B
let Point P satisfy condition it is equidistant from A and B
P =(x,y)
find distance b/w P and A, then Pand B and equate them you will have the locus
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You take x = 0 in this case
@round raptor can you use midpoint theorem here?
Can we use ?
.close
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So its 0,3?
yea its on y axis
Oh ok
Its saying no idk y
Hol up
I think you calculated it wrong
Come in #help-14
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Tried a lot of different stuff nothing works I am lost give me a general direction please
,rccw
What have you tried?
Mhm, it looks like multiplying by denominator conjugate doesn't really help
Let's try to multiply by numerator conjugate instead
i.e.
I kinda tried that as well with a-b = (a^2-b^2)/(a+b)
Modus
And I see it's enough to expand the top part
Now i am getting somewhere
You should just do the conjugate of both the top and the bottom. If you only do the top you are not going to be able to remove the root from the bottom.
But also i don’t get the denominator part
If you multiply sqrt by sqrt it’s just gonna be 2x^2 + 1x inside?
Did you get 2x-8 at the top?
Ahh no
It will be possible, but it's a little bit tricky in this case
What's more, sqrt(2x+1)^2 isn't 2x^2 + 1
The sign wasn’t supposed to be included?
(a-b)(a+b) = a^2 - b^2, right?
No it’s still in the sqrt like there but with sqrt still
When you square a square root, what remains is the number under the square root
So just 2x+1
Yes my bad
And hence, it becomes 2x+1-9, you see that?
Yes
= 2x - 8
Modus
I am talking about the denominator where sqrtx * sqrt(2x+1)
Don't touch it yet, believe me
Now, observe that 2x-8 = 2(x-4), I hope you can notice something right now
I see it
Thats tough to see
Man I wish I had that kind of vision
Maybe I am tired though, thanks for your guidance
Closed by @wet haven
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.reopen
✅ Original question: #help-27 message
I don’t know how to change the original question
I didn’t wanna ask again but I know I won’t do it otherwise
,rcww
About the previous one
So I know how the module part has to be done the 3 to the power is what gets me
Is L'Hôpital not allowed?
Well I can’t say for sure I know it but I am basically retaking this class
But I think we haven’t learned it yet
So no
I see
But you could probably do it with L’Hopital
Wdym
In the sense it takes 20x less time to do it with L'Hôpital
Exaggerating
But it is much faster
I would have trouble with it even so
You just find the derivative of the numerator and denominator and then plug 4 in
Sqrt with a-b and such would get me
But yeah this isn't the point if you haven't learned it yet so nevermind