#help-49
1 messages · Page 174 of 1
but i was explicitly told "do not try to show that the infimum of the distances between the points in two disjoint closed subsets is positive"
while also being told "first use open balls around points of A and B to construct disjoint U and V and show that their closures are disjoint from B and A"
so how am i supposed to construct balls around points of A and B without my idea
or am i misreading this
maybe this is supposed to mean inf{d(A, B)}
in which case that can be zero if the sets get arbitrarily close
but in my case it works because i consider a fixed point a in A
ping me if replying
@lavish venture Has your question been resolved?
@lavish venture Has your question been resolved?
@lavish venture Has your question been resolved?
@lavish venture Has your question been resolved?
@lavish venture if I write in topology terms can you translate into metric space terms
uhh perhaps
ok don't worry I'll write in metric space terms
i can't seem to formulate a proof for why the closures of U and V are disjoint
for each $a \in A$ i defined $\delta_a = \inf{d(a, b) \colon b \in B}$ then just took balls of radius delta/3 around each point and took the union to cover A
knief
i did the same thing for B
they are clearly disjoint but im not sure how to put it formally other than its fucking obvious, by construction
I'm saying if they are not disjoint, that point must be a limit point of both not in either
starboard moment
you mean construct sequences x_n in U and y_n in V such that they both converge to some point x in the intersection of the closures of U and V?
like
let $x \in \overline{U} \cap \overline{V}$ then define $(x_n)$ and $(y_n)$ such that $x_n \to x$ and $y_n \to x$ where $x_n \in U$ and $y_n \in V$
knief
uh let me go back to topology world
from this i get something like
what was it
$d(a_n, b_n) < \frac{2}{3} d(a_n, b_n) + \varepsilon$
knief
how did you define closed subsets?
just got home
going to write it out
slowly
@lavish venture
complement is open
perfect
what did you have in mind
$B_r(a)$
knief
we use $B_2(x;\varepsilon)$ lol
Xetrov
why 2?
form of metric
oh you mean for notation
ya
(I'm still here, I'm just in a mess)
$\bar{A} = A \cup {\text{limit points of A}}$
ok?
Xetrov
yes
@wary trail what if we show that $\overline{U} \cap B = \emptyset$ and $\overline{V} \cap A = \emptyset$
knief
then from here we must have that $\overline{U} \cap \overline{V} \subset X \setminus (A \cup B)$
knief
thus if $x \in \overline{U} \cap \overline{V}$ then $d(x, A) \neq 0$ and $d(x, B) \neq 0$
knief
wait but cant d(A, B) = 0
what if neither are compact?
Why does compactness matter?
my prof said not to do this because apparently theres a counterexample
based on neither of the sets being compact
let me read what you have
yea
would this work?
^
since we already constructed U and V to be disjoint
if we show this then the next line follows
Greater than zero for all a in A
yea
@wary trail
do you know anything about baire spaces by chance?
Let $(X, d)$ be a metric space and $Y \subset X$; thus, $Y$ inherits a metric $d_Y \equiv d\mid_{Y \times Y}$ from $(X, d)$. Suppose $(X, d)$ is a Baire space and $Y$ is open in $(X, d)$. Show that $(Y, d_Y)$ is also a Baire space.
knief
so i consider a sequence $U_1, U_2, \dots \subset Y$ of dense open sets in $Y$
knief
then need to show $\bigcap_{i = 1}^{\infty} U_n \subset Y$
knief
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The ratio of the lengths of the two shorter sides of a triangle is 1:2. The angle opposite the shortest side is 30°. Find the measure of the largest angle of the triangle.
pick a side length for one side and use the ratio to find the other side length
i would also recommend in your drawing that you make more of a distinction between the lengths of AC and BC, they look very similar right now
wait so
can u give me example 
okayy
i’m very lost whenever it comes to ratio cause i think that one side is 1 other 2
when we have ratios between side lengths, for example let's say AB:BC = 1:2, that means that as a fraction AB/AC = 1/2
you can do a little algebra to solve for one of the sides once you have the equation set up (and you know the other side)
ohh
it's ok just to pick one of the side lengths in this example, since the angles in a triangle depend only on side ratios, not the actual side lengths
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this is based on the series for e^(-x^2) ?
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I’m stuck on parts 3-5. I did parts 1-2 with no issue (part 3 is the third picture so I guess I technically did do it but i don’t know if it makes any sense. I just need help with this to the end if anyone can help walk me through it. This is due tomorrow and determines my grade for the end of the marking period so im really stressed about it :/ )
@simple needle Has your question been resolved?
bruh its been a whole hour and 30 minutes how have i not received any reply yet😔
is the third pic ur work for 3?
yea but i dont think its right
someone in a different homework server told me to do it
icl im trying to decode what u did so give me a min
yah idk whats going on
its fine
my older cousin is helping me over the phone now
none of the servers have been able to help so i just gave up here anyway
.close
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Im about to finish Real Analysis I (still got differentiation, integration) and still don't know the derivative of x!
it was my sole purpose for taking the course
can anyone tell if its differentiable?
im assuming its f: N -> N since I've never seen it take negative or fractions
$x!$ is a constant no?
張嘉棋
a constant?
I meant the function x factorial
or I guess it behaves more like a sequence
well $x!=1234...*(x-1)*x$
張嘉棋
right and since I'm assuming the domain cant be the set of rationals then it can't be differentiable since it has to be dense
i think there is some sort of sum in the derivative
oh wait in reals
so yhhh cannnot derive
unrestrict it out of the reals?
is it worth learning?
depends if you enjoy it
I never do it for enjoyment, more to fill my curiosity and apply to other fields.
This level of math takes too much time and energy
me when quant
I thought about complex analysis but idk if anyone uses imaginary numbers
ive considered topology
depends how much u like shapes
imaginary numbers make alot of areas in mathematics nicer to work with
Not at all lol but its useful in some areas in ML I hear
Thats actually pretty interesting
depends on area u wanna look at tbh
if u wanna do ML, don't take maths classes
take ML classes
gotcha, im still not sure what I will do for my PhD. Im in between Statistics and CS which learning more about functions in RA which has helped me with stats but not CS
i made the mistake of taking pure maths classes when i enjoy more quantitative finance
actually? this is what I was scared of too
but i'm lucky in the sense that, quant finance is pretty forgiving in what masters/phd they hire
lol im know im getting way off topic but I at least want to know, how do you like quant finance?
lets move to DMS
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How to get from $f'(x)$ to $f''(x)$?
The answer key says that it is $(x-2)e^{-x}$ not $(x-1)e^{-x}$
luna-maia
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u split the contour up
$\gamma_1(t) = it, t \in [0, 1]$ and $\gamma_2(t) = i + t, t \in [0, 1]$
Charky
Charky
u should get the sum of two integrals
@molten bay Has your question been resolved?
How did you get 0 and 1?
[01]
it doesnt matter, but usually for line contours between point $\mathbf{a}$ to $\mathbf{b}$ u do $(1 - t) \mathbf{a} + t \mathbf{b}$
Charky
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I got the right answer but
act i didnt
the answer key has a negative in front
but i dont
the answer key says this but i have a negative in front of the 3
in the numertor
and your denominator is the same?
Yeah my denominator is the same
same signs
can u show ur working
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How can I solve this integration?
that integral doesn't make sense
the bounds of integration on an integral with respect to x can't depend on x
@molten bay Has your question been resolved?
are you sure it's not dy dx
I see
Yeah
this would make a bit more sense
But i didn't understand it properly
What is the difference?
Can we not assume it constant?
in yours it's dx
which cant be possible at least idts
idk what you mean by assume constant
Why?
Can we find integration of it?
Actually no
because if it's as you stated then it just diverges
see for your question what im understanding after a lot of looking is
The inner integral is:
Since the integrand does not depend on 𝑥 it can be factored out
Thus, the inner integral evaluates to
leaving us with the outer integral
since the integral of an infinite quantity over any nonzero range is also infinite, we conclude that the given double integral diverges
i would look for a second opinion though
$$\int_{0}^{\infty} \int_{x}^{\infty} \frac{e^{-y}}{y} , dy , dx = 1$$
Technoblade Never Dies
since you can write it as $$\int_{0}^{\infty} \int_{0}^{y} \frac{e^{-y}}{y} , dx , dy = 1$$
Technoblade Never Dies
@molten bay Has your question been resolved?
Thank you so much
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what do they mean by change of sign
oh so like different signs?
Yes
different signs proves that they lie between x=1 and x=2?
And that means, geometrically, that between x=1 and x=2 you cross the x axis
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i dont understand the last part
why did we stop at 0.36
how did we determine 0.36 is the root
Convert every answer to 2DP as you're going. $a_2 = 0.30, a_3=0.38, a_4 = 0.35, a_5 = 0.36, a_6 = 0.36, a_7=0.36$
Oliver
The answer sheet is just saying that you got $0.36$ 3 times in a row, so you can be pretty confident that's the answer
Oliver
right but why 0.36
This is a convergent method, meaning over time you get closer and closer to the real answer. Once you're getting the same thing 3 times in a row, that probably means it's as close as you're going to get
If you want you can calculate $a_8, a_9, ..., a_n$ and they will get more and more accurate but to 2DP will still be 0.36
Oliver
So it makes no sense to keep going once you've had the same answer 3 times in a row
I assume the Newton-Raphson method
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hey notation question!
how do i write the chain rule using leibniz notation?
i just do $[f(g(x))]' = f'(g(x)) g'(x)$ because it's convenient
Percy
but tbh it took me forever to memorise the chain rule because i couldnt write it in leibniz notation lolol
is this what you mean
tbh chain rule is even more obvious in leibniz notation
HMMM
yeah I use this
well i get it like that but
more intuitive
its the reason why you can treat dy/dx as a fraction and it works out
^
when we have f(g(x)) stuff, do i just take the derivative with respect to g(x)?
i mean i know thats the derivation but notationally that's weird as hell
percy btw u not responding to my dms?
wut?
hold on i didnt see it
in both cases it's the derivative of the composition w.r.t. x
I mean.
I know.
But
okay
write me the chain rule for $\frac{d}{dx} \sin(3x)$ in leibniz form
Percy
(this is totally googleable im just bored apparently)
artemetra
it's the same formula
u just said u didnt know latex
gpt
$\textbf{Step 2: Differentiate } y \text{ with respect to } u: \[1mm]
\frac{dy}{du} = \cos u$
Technoblade Never Dies
yes but 👀 how do i write the sin(2x)
and then substitute
Uh Percy r u talking about chain rule differentiation?
ah so its just inconvenient af
Just differentiate from outermost function to innermost
isnt that hwat i said
So for sin(3x)
i know how it works
Ok
im asking leibniz notation for it
oh u mean substitutions
sorta, this really only works well when you make the substitutions technoblade never dies mentioned
these
hmmm yeah thats fair
to be fair i was taught trig differentiation conceptually like differentiate the trig func with the same angle repeated, and then multiply by derivative of the angle
I was never told it's chain rule
I only found out recently
because the dy/du would then be derivative of sin(u) which is cos(u), as you can see u did not change
i should nick
nvm I cant
I should ask a mod to nick me
so it says as cos(3x)
and the du/dx part would be the derivative of u w.r.t. x, which is 3
why not? /nick
it does not
eh personal preference
i think the question of "write this in leibniz notation" doesn't make sense in the first place
for rate of change qsses I find this notation so manageable
regardless of notation the derivative would be the same function
i replied that to techno telling us about the trig thing but slow net lol
oh woops
oh
yeah
it does suck that we were taught to memorize rather than the concept
fire isnt it
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so im trying to get the inverse of the first line but i did it totally wrong
It seems like you cubed the equation and missed a term or two
$(a+b)^3\neq a^3+b^3$
00100000
well, yes, iwould cube the equation
so 2->3 is wrong
okay, so what does the term change into?
precisely, 2 terms
this is binomial theorem with n=3
i am not sure what that is or means
whats the theorum?
thats what i tried
pascals triangle
okay, what is it?
$$(a+b)^3=$$
$$(a^2+2ab+b^2)(a+b)$$
00100000
give me a sec
im notdoing that 😭 no way
soo it adds the top 2 terms
its not ideal to cube both sides of the equation in its current state
as it'd generate more undesired terms
and then you can see that it equals $$a^3+2a^2b+2ab^2+b^3$$
line 3 is wrong
also (1/2)^3 isn't 1/16
Yeah better to take the 5 to the LHS
00100000
Then cubing the equation
btw do we even need to do any cube of a sum expansion
Readabove, theyve already told me that
ann dni
definitely not
ideally you'd want to first isolate $\cbrt{y-3}$
ℝαμOmeganato5
wait actually, you do
what's the problem
first
you'd either have to do it on the left or right
I think you gotta cube one way or another to isolate the y?
because there will always be a binomial term
i think OP should post the full qs
I already said that 😐
the question is fine
no this is fine
unlike the cocaine guy
i already did, i said im finding the inverse of the firstline
(there was more to the qs they sent this before in a diff chat and raged)
dni sami
i didnt rage
omg
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ohhh, I see
;=;
grah
💀
I sorry
Donot fucking talk tome anymore if youre gonnaspout bs like that. I am just trying to fuckingleanr but apprently thats not okay
ok woah
.
I got frustrated because someonetold me that its simple math when im strugglingith it
$$x = \frac12 \cbrt{y-3} + 5$$
one of your first goals would be to first get \
$\cbrt{y-3} = \what$
uhhhh... look, your question was well-defined and fine
Thats pretty much just callingme dumb. I know its simple. I struggle with it anyways (THATS WHY IM HERE)
ℝαμOmeganato5
we're all at different stages of our math education; don't listen to people putting you down for not having had the time or experience to study something that they're already learned
you are not dumb
let's create the idea
No bc both him and some otherperson are trying to make me look bad and thats notokay
When i react to that im somehow wrong!!?!
ive already closed the channel. Its not worth it
you're not wrong, it was just surprising
feel free to reopen it; we'll finish helping you with the question
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oh, it's too late now
oh wait oops
actually, while I have this channel, can someone explain to me the general approach for finding the phase portrait of an ODE that's not in $Ax=0$ form?
00100000
I know that you can take eigenvalues of a matrix when it's a nice $Ax=0$ equation
00100000
Yes, and i didnt ask that this time. So butt out (and i then changed my question to asking howtofind theinverse. so like bro)
ok I guess I give you guys permission to talk in my help channel lol
no no it's alright
i don't see why you think there's anything hidden behind what was being asked.
I'm just asking kind of an open question
lalnashef is mad
I'm just confused on what's going on with this whole thing to be honeset
were you the second person she was referring to??
ok anyways, my textbook shows examples like this diffeq
rightfully so
stop
which clearly can't be expressed as $Ax=0$ (I haven't looked at the non-homogeneous cases)
00100000
Don't worry everyone has their own pace of learning , just learn ignore those who call you dumb.
and of course, finding critical/equilibrium points is easy
@zenith mirageif you feel like you are being mistreated by users, you can raise a ticket with @shadow scaffold.
you have the option to block them, but it is also not productive to just leave as there are others present that would be willing to help if you have the patience
itsevery timei try to learn. how do i ignore the majority of people anytime i try to be better
Hey a lot of people I have seen here are genuinely nice
ive already blocked them and toldthem to dni
but figuring out how to draw the phase portrait by hand (without graphing the vector field) is very confusing
yeah, this community is mostly great
do you need all solutions
no
just the phase portrait
or like, a general strategy to approach ones where I can't find the eigenvalues for a matrix of the system
and also, ways without finding the explicit solution of the ODE
I can find more explicit examples
sorry I can't do that rn I'm dumb
chatgpt basically just told me "well, guess the solution"
and then when I told it "how do I do it without guessing?"
I would do derivative operators
it told me "lmao turn it into a PDE"
and of course, I don't think turning it into a PDE would help me too much... 💀
what's a derivative operator?
you mean, like, a linear combination of $\frac {d}{dx}$?
00100000
ohhhhh, ok I see I see. I'm a little stupid about the words
but this is really hard to do by hand, right?
I mean lemme try
no but
I need ones at this level of general detail
is it of t
and plugging in points would be really hard
well one way to get a good enough idea of what's going on is to linearize the system around equilibrium points
linearize it? now that sounds hot
you're telling me I can turn this linear?!?!
that's awesome!
and this should generally work?
I think for another set of examples in the book, it talks about different strategies for phase portraits of conservative equations
1.5.3. Conservative equations. In this section we consider the particu-
lar case of the di!erential equations conserving a given function. We first
introduce the notion of conservative equation.
and it mentions using level curves
but honestly, I am really bad at multivar
and don't understand that either
I'll ask about it some other time tho
the idea is that around equilibrium points the system behaves roughly like a linear system
wdym by that?
so it gives you a rough shape of the trajectories of the system but it's not perfect obviously
is it good enough to generally draw a convincingly accurate phase portrait?
say, on an exam or something?
lol
go check out the page, it's gonna do a better work than me
yeah
that's prolly the best you can get away with without literally plotting the vector field
ok, I'll give it a read. thanks for the resource! this phase portrait stuff has really been killing me
sounds good
thanks everyone :^)
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\frac{a^2-8a-20}{a^2+5a} > 0
꧅
ok consider positive case first both denominator and numberator > 0
i get a> 10 or a <-2 from numerator
and a> 0 or a <-5 in denominator
so how do i know the priorities of and or
which do i take first
do you have to do it with casework?
there is an easier way to do this entire problem if not
whats casework
like this "consider positive case first, then negative case"
dont have to but i still want to understand if im supposed to take and first or or first
well
wavy curve
yes
if you really want to
you can distribute the and over both ors in a sort of FOIL-like way
and get
(a>10 & a>0) or (a>10 & a<-5) or (a<-2 & a>0) or (a<-2 & a<-5)
2 of these and-clauses will collapse into falsehood and you can apply the identity law FALSE or P = P
thus being left with (a>10 & a>0) or (a<-2 & a<-5)
a>10 & a>0 then simplifies to just a>10, because any number greater than 10 is also automatically greater than 0
by the same token a<-2 & a<-5 simplifies down to just a<-5.
so you get a<-5 or a>10 for this.
i definitely recommend against this method though!!!
whats this not casework method then
well, you still factorize num and denom as you would otherwise
so $\frac{(a-10)(a+2)}{a(a+5)} > 0$ yes?
Ann
ye
then you know the number line is broken up into 5 intervals by the points 10, -2, 0 and -5
so... well ok it still kind of looks like casework except that you no longer need to fuck with ands and ors
but basically you can make a sign table
ok good
Interval | a<-5 | -5<a<-2 | -2<a<0 | 0<a<10 | 10<a
---------+------+---------+--------+--------+-------
a-10 | | | | |
a | | | | |
a+2 | | | | |
a+5 | | | | |
---------+------+---------+--------+--------+-------
Product | | | | |
like this
and fill out each row with "+" and "-" signs accordingly
and then multiply those
triple backticks to enter code-block formatting
and then i just manually entered | and - symbols
with some copy and paste
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herplp is the "claim" alwyas Ha?
asoruru its 2 am idk if im making sense
Sure I guess?
I think the "claim" thing is something your instructor would have made up though
OH AHHAHAAHAH
you generally just deal with the null and alternate hypotheses
I SEE I SEEE
okayokay tyyy can i ask one moreee?
normally we would diivide for level of significance andik that two tailed = one of each 0.05 becomes 0.025
but like when writing the final level of significance wiill it be 0.05 or 0.025..
wht i noticed from my teacher is at first its 0.05 but then when shes in step 5 she changes it to 0.05 which kinda makes me confusedd
the level of significance doesn't change
this is my last question 💟
ohh it will stilll be 0.05?
and 0.025 is just the idea?
we split the confidence in two because we have a two tailed test
but it's still the same significance
(as asked for in whatever problem you're solving)
okayokay gotchuu thank you!!!!
i cna sleep now hahhashhahd
@dark locust Has your question been resolved?
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!help
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i need to find (h,k) for -3x^2 +7x -2
for now i did h = -b/2a
h= -7/2(-3)
h = -7/-6
h = 1.66666666666667 or smth
idk if thats good
That is correct.
Just plug that into the original equation and solve for y.
or 1.66
y = -3(7/6)^2 + 7(7/6) - 2
that will give k?
It better.
alr ty
And the negatives cancel out.
minus over minus
yes...
Yes, the negatives cancel out.
$\frac{-a}{-b} = \frac{(-1)a}{(-1)b} = \frac ab$
rafilou is not not born in 2003
ill do this
👌
i got
-4 1/2 + 8 1/6 - 2
but i dsont think im supposed to have those entire numbers
-4 and 8
,calc -3*(7/6)^2 + 7*(7/6) - 2
Result:
2.0833333333333
do i write 2.083 or just 2
I would write the fractional form.
,calc -4.5 + 8 + 1.6
,calc -4.5 + 8 + 1/6
Result:
3.6666666666667
Wrote that wrong.
,calc -4 + 1/12 + 8 + 1/6
Result:
4.25
it gives me 4.08333333
Yes, you see that on the next line.
Do you see where you possibly made your mistake?
which mistake
Well, you got the wrong answer.
What do you think plugging 7/6 into the equation was doing?
Yes. And you were getting the wrong result.
oh
i didnt put it into like
the big form fractions
49/12
and not 8/1/12
im not understanding whats happening here tho
,calc -4 - 1/12 + 8 + 1/6
Result:
4.0833333333333
-49 - 24 = -73
-49
its -?
oh yeah
it is
k gave me
25/12
but do i write it lik that
because the coordinates
dont have fractions
like (h,k)
You can estimate where the point should be if you want to plot it.
so do i just like put it into decimal to draw the point
then when im writing h,k
i put it into fraction
On a graphing program?
its on paper
On paper, I would use fractional form.
ight
Unless your teacher explicitly tells you write an approximate answer to n decimals.
eg. Accurate to the hundreths would be 2.08.
alr
well
i used decimal to find where the point is located
but then i wrote it into fraction
to locate it
like
if im writing an equation
im typing it into fraction
but i turned it into a decimal
to know where it is in the graph
cuz idk how to find it if its 7/6 25/12
You could also write 2.083 with a bar over the 3.
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Hi how do you start
@empty ivy Has your question been resolved?
we need to get a quadratic in tan theta
im not getting how to do that tho
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can someone help me answer this please
what have you tried
should be 3t but otherwise sure
dont do this
use vectors
starting with 15sin(3t)+20cos(3t)
do you know how to find R
yeah im trying
ill show u after
there is a formula for it if you know it
this is what I did
whats the formula?
the formula is what you did just without the steps in getting there
shit i deleted it
lmfao I saw it
it went before I could interpret it
ok one second ill type it again
Thank you baby Yoda
d =15 sin 3t - 20 sin (3t+pi/2)
d= 15i - 20 j
d = root 15^2 + 20^2
tan alpha = -20/15 = -4/3
@leaden seal
uve used vectors
yes
if u do it like this u are so cooked
ummm
its the way I've been taught
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ok it is a huge process and i was particularly taught never to do this lol
but if u want to u can 👍
this isnt how ive seen it taught
typically you find R
then you have
d=R[ 15/R sin(3t) +20/R cos(3t) ]
then solve cos(a)=15/R, sin(a)=20/R for a common a,
should only take like 3 lines or so
.reopen
✅
that whole middle section could just be skipped
if you have Asin(t)+Bcos(t)
then R=sqrt(A^2+B^2), i havent seen someone have to write a derivation
is this correct for this
did you mean npi rather than n/pi
seems okay
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hey
im kinda of confused how did we get e^-2/3?
how tho
$e^x = \sum_{n=0}^{\infty} \frac{x^n}{n!}$
doaby
so they replace x with -2/3
but if you start at n = 1 instead,
$e^x = \sum_{n=0}^{\infty} \frac{x^n}{n!} = \frac{x^0}{0!}+ \sum_{n=1}^{\infty} \frac{x^n}{n!}$
doaby
and how do they end up with e^-2/3?
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How do you do this? I was going to use the Trapezoidal rule because that's what this lesson was about. But the intervals aren't equal.
You don’t necessarily need equal intervals for estimating
@teal solstice Has your question been resolved?
it says
use 6 right rectangles
they explicitly want you to use the right-endpoint rectangle rule
and yeah the intervals are not equal but thats ok
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How to find theta
....what
Idk I am not sure how to do it
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.
I lost the original question paper
But the line that pass through origin is a tangent
Original
Sorry typo
Ohhh thank you
Wait I think there is part 2
To find the radius of corcle
Oh I think I see how to do part 2 now thank you for the help guys
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Hihi for (b) can I check ik area is area of y+2x=17 from pt q to o- area of B which is x^+2-(17-2x) and integrate
But can I check how do we know if it's x^+2-(17-2x) or (17-2x)-(x^2+2) I can't differentatite between which to minus clf one explaining and why can't I do integral of A-B to find the area? Like in one step not total area - off
Have you found P Q R?
Can you just explain(differently) what your problem is? Because A-B doesn't give you what you think it gives.
No I alr got A
I know we need to integrate A and sub in coordinates - the area of interaction between the curve and line
uhm, you say you have A
But for the area of intersection how do we know if it's curve -line or line - curve that's the thing im confused abt
Hmm I did alr get the area of A
This is the to find the area of B right
uhm, no
Thing is I'm confused about which day to do it
Oh really am I getting smth wrong
U mean A+b is area from pt Q to O of y+2x=17 right ?
think... because saying more will be condmened by helpers as spoon feeding just think about it...
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The computed value of the Pearson’s r from the sample, (r = -0.01) is relatively greater than the critical value (±0.361), and therefore do not fall within the critical region. In this effect, we FAIL TO REJECT the null hypothesis (H₀: ρ = 0), and REJECT the alternative hypothesis (H₀: ρ ≠ 0). With that said, it can be concluded that there is no sufficient evidence that the amount of study time in hours affects the grades of Liceo G11 ABM students in General Mathematics.
Guys is the mean symbol correct? My teacher only taught as us to use the u symbol but i feel like rho/p matches this more.
ttytyty
$\mu$?
Percy
mu is the standard symbol for mean
yesss! i will use thiss
but mu and rho are practically the same right its just a matter of preference?
asuahsha okayy!
ive never seen $\rho$ used. you can if you wanna i guess.
Percy
i see rho and i think like density and stuff.
oh gosh i used rho for pmy previous scaffold i probably got wrong there 😭
anyway, thank you!
Hiii everyone, I plan to take the edX MITx Micromasters in Probability and Fundamentals of Statistics and was wondering if someone here would take it too. I have 3 years of not doing math at all and wanted to practice with someone.
My name is Laurent and I'm from Panama. Best!


as my mean symbol