#help-36
1 messages · Page 73 of 1
Np!
I haven’t done it myself. Can you show your reasoning?
Wait, where did you calculate the blue triangle area?
Oh my bad
Is the area of the blue triangle just 5/6?
Alright that looks good, good job! If you want/need an exact answer then you can try the similar triangle method which doesn’t involve any trig
Or does the 13/18 happen to be exact?
What do you mean by exact
Like is it actually just 13/18
So the pentagon area is 13/6 and the area of the rectangle is 3 so you multiply each by 6 and get 13:18
So yeah it is exact
Oh sweet alright
Thanks for your help
You’re welcome!
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number 16
help
i tought it has but the answers say it doesnt
why does the limit not exist
cant we do h*(2+h)/h = 2+h=2+0=2
Try taking the limit from both the positive and negative side and see what results you get.
but why cant i do this
Did you try doing what I said to do?
okay okay
so
if we take something negative a little less than zero
the limit will be negative and if we take something a bit positive it will be positive?
Yes, but how does that affect the limit from each direction in this particular problem?
does this show it doesnt exist?
It does, but it's important for you to understand why it is DNE.
yeah thats what im tryong to do
so the limit is not equal from both sides so the function is not differentiable?
do i check from both sides all the limits that go to a number?
You don't always have to. Note that h in the denominator cannot equal 0, so in that case you should check because that is what the limit is approaching.
Although you can technically eliminate the h in the denominator mathematically, you must always consider the original equation/expression.
👍
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radius and interval of convergence?
i think lim is
radius = 0 and interval = {0}??
help
<@&286206848099549185>
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hi
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,rccw
Oh sorry
Which among the numbers in the set is the solution of the following
Like we need to do the solution
For the following Trigo equation
isn't this trig identities?
Yea
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Hi.
I need help with this:
"Let A = {1, 2, 4, a, b, c}. Identify the following as true or false.
c) c∉A
e) { } ∉ A"
I got these wrong. I said that "c" and "e" are false. The book says the opposite.
Isn't c an element of A?
The book also says that for any set A, since there are no elements of Ø that are not in set A, then Ø ⊆ A. Is "e" right because you can't say that Ø is an element?
Neither are right. Maybe they mixed up true/false in the negation?
I think e) is true since you don't really refer to an empty set as an element of a set unless you are talking about a power set. In this case, you would say the empty set is an element of the power set. Otherwise, you have to say it is a subset of A because an empty set is a subset of all sets, at least that's how it is defined. For c, however, I have no clue.
Oh wait yes e is true. It's a bit annoying with the negation haha
But yeah the empty set is not an element of A, so { } ∉ A is a true statement.
As for c, it is pretty clear that c is in A, so c∉A should be false.
oh. so would Ø also be considered a set?
gotcha. still didn't register that well that it is actually a set
thanks! still hadn't gotten that it was actually a set. sometimes i understand things but usually forget what they're called
i feel like it should be completely false. but then i get worried that it was something I didn't understand
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so I need help with this one
I cant seperate it like so but is there a way I could seperate it?
ik the answer is 2/3 x^3 + 9/2x^2 + 4x + c im just wondering if there is some way I can seperate them (even though they arent constants) rather than multiplying them
Not really. You could do integration by parts, if you've learned that
but the simplest method, by far, is just multiplying
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So I factored it but im not sure what to do from here $\frac{5x(x-3)(x-2)}{3(x-2)(x+1)}$
Matt
you can start with:
- domain
- limits on ends of intervals of th doman
- asymptoes, their equations
4 zeros of fucntions
also notice that (x-2) is reduced
ti iwl make yoru funciton easdier
but still x cant be equal to 2
so it is hole there
@tranquil pine Has your question been resolved?
ok i get the rest but im not quite sure
how to find the asymptotes for this equation yk
since i graphed it and its slanted
theres no vertical asymptotes so thats whats confusing me yk
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Complete the Square.
? @trim sigil
tanx= sin/cos
And below: Cos²(x) +sin²(x)=1
$2\cos^{2}x-1=\cos2x=\frac{1-\tan^{2}x}{1+\tan^{2}x}$
B-eard
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what's the sum of the roots of this equation
it's very easy, but time-consuming, I don't know if anyone will want to do it here, you have to put each denominator into a product form, and then multiply both sides of the equation by the common denominator, etc.
there is an easier way
faster
why do you care
🙂
I'm not forcing anyone to solve it
got it you jsut wanted to share it, )
i see
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he just wants the answer and is lazy to solve it bruh
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Do i use binomial
since it looks like for a binomial distribution
I thought i should use n trials 100, k be 3 and probability be 0.02
so then find P(X=3)
is this right?
<@&286206848099549185> Hi, just need some small help
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<tikz;siunitx;enumitem>
\usetikzlibrary{decorations.pathmorphing}
Three identical \qty{8.50}{kg} masses are hung by three identical springs. Each spring has a force constant of \qty{7.80}{kN/m} and was \qty{12.0}{cm} long before any masses were attached to it.
\env{enumerate}{[a)]
\ii Draw a free-body diagram of each mass.
\ii How long is each spring when hanging as described?
}
My sketch of the problem is as follows:
\env{center}{
\tikz{
\tikzset{
spring/.style={thick, decorate, decoration={zigzag, pre length=0.1cm, post length=0.1cm, segment length=6}},
rect/.style={fill=orange!70, thick, draw=orange},
}
\draw[thick, black] (0,0) -- (2,0);
\foreach \y/\label in {0/A, -2/B, -4/C} {
\draw[spring] (1,\y) -- (1,{\y-1});
\draw [rect] (0.5, \y-2) rectangle (1.5,{\y-1}) node[midway,text=black]{\label};
}
}
}
And my free-body diagrams are as follows:
\env{center}{
\tikz{
\tikzset{
rect/.style={fill=orange!70, thick, draw = orange},
weight/.style={->, thick, red},
sf/.style={->, thick, blue}
}
\foreach \z/\label/\nextlabel in {0/A/B, 2/B/C, 4/C}{
\draw [rect] (\z, 0) rectangle (\z+1, 1) node[midway, text = black]{\label};
\ifnum\z<4:
\draw[weight] (\z+0.3, 0) -- ++(0, -1) node[left, anchor=east] {$w_{\label}$};
\else:
\draw[weight] (\z+0.5, 0) -- ++(0, -1) node[left, anchor=east] {$w_{\label}$};
\fi
\draw[sf] (\z+0.5, 1) -- ++(0, 1) node[right, anchor=west] {$F_{\label}$};
\ifnum\z<4:
\draw[sf] (\z+0.6, 0) -- ++(0, -1) node[right, anchor=west] {$F_{\nextlabel}$};
\fi
}
}
}
My questiion is, are my free-body diagrams correct? And how do i go about calculating the extended length?
@tranquil pine Has your question been resolved?
@tranquil pine Has your question been resolved?
I think they are okay
I suppose you just have to find the raw values for each force now
hm
so lets take our origin to be the ceiling
we have [
F_A = kx_1\
F_B = kx_2 \
F_C = kx_3
]
i guess?
but for the x's what are we counting as the elongation?
no wait
[
w_C-F_C = 0 \
F_C + w_B - F_B = 0\
w_A + F_B - F_A = 0
]
I'm sorry for saying this now of all times, alex, but although I can interpret force diagrams, the last time I dealt with spring forces was 5 years ago. So I'll have to spend some time rejogging my memory
[
mg = kx_3 \implies x_3 = \f{mg}k\
kx_2 = mg + mg = 2mg \implies x_2 = \f{2mg}k \
kx_1 = 2mg + mg = 3mg \implies x_1 = \f{3mg}k
]
would this be correct then i guess 
oh no worries
well, you've assumed that the entire system is at rest right?
nothing is accelerating anywhere?
therefore the sum of all forces is zero for objects A, B and C?
indeed
then I will trust you on this one
For a more concrete verification I'm going to do a gigachad move
which requires swallowing my pride
<@&286206848099549185> I need someone to take my place to help with calculating simple forces involving springs
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hi, is the answer for this
is "-ln | sec z | + C" ?
if not can anyone show me the step by step on how to solve this
How did u get -ln""
Show ur work first
@zealous parcel basically 1+Cot^2 is csc^2 right
yes
Yea?
ooh it will become csc (z) cot (z)
Ya
whats the next step?
Express everything in sin cos
Express it as cos/sin^2
@zealous parcel any more doubts?
still confused huhu
Substitute man
isnt cot is 1/tan?
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(lg(a))^(1/2) + (lg(b))^(1/2) + (lg(a)^(1/2)) + (lg(b)^(1/2)) = 100.
ab = ?
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.
@thick grotto Has your question been resolved?
@thick grotto Has your question been resolved?
What's "lg a"? Is this a new way to write log(a)?
$\sqrt{log(a)} +\sqrt{log(b)} + log(\sqrt{a}) +log(\sqrt{b}) =100$?
G. Spark
This does not match your description at the top.
But that is incorrect, so struggling for the problem statement.
Maybe possible to get rid of the logs?
lg(a) = log₁₀(a)
@thick grotto Has your question been resolved?
@thick grotto Has your question been resolved?
@thick grotto Has your question been resolved?
But here lg(a) means log₁₀(a). This is a simple decimal logarithm.
I don't rule out that it could be a binary logarithm (which I doubt), but even so.. I'm already interested in finding an answer to the question, is it possible to find a solution to this problem with a decimal logarithm?
yeah so $\sqrt{\log a} + \sqrt{\log b} + \frac{1}{2} \left(\log a + \log b \right) = 100$
south
or $p + q + \frac{1}{2} \left(p^2 + q^2 \right) = 100$
south
$p^2 + q^2 + 2p + 2q = 200$
south
ah but $p^2 = \log a \implies 10^{p^2}$ so we need to find $10^{p^2+q^2}$ for $ab$
south
the only integer solutions should be p = 8, q = 10
and like p = 10, q= 8
I'm not sure how to prove this however
but then if all terms are integers, the solution to p^2 + q^2 + 2p + 2q = 200 will give all the integer solutions of the original equation
ah right, add +1+1 to both sides to get $(p + 1)^2 + (q + 1)^2 = 202$
south
if it helps we only need to check the squares from 1 to 100
like q + 1 = 11 is the same as p + 1 = 9
nice problem
Its easy to observe 0 <= p,q <= 11
So u don't have many values to test @thick grotto
@thick grotto Has your question been resolved?
Thank you for your responses. I think this is enough for me to try to find a more accurate explanation of the solution. Anyway, if I don't succeed, I will ask this question again. Goodbye.
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Merineth
Now I’m supposed to take the primitive of each term, simplify and then put in x = 0 and y = 1
However how tf do I take the integral of
$\int \frac{dy}{dx}e^{-x^2}$
Merineth
apply the integrating factor
Product rule or integration by parts
I(x) = e^integral(P(x))dx
then y = 1/I(x) integral(I(x)Q(x))dx
Q(x) is -e^x^2(sin2x)
Merineth
just use the tabular method (DI method)
an easier method of IBP
IBP?
i never learnt the the original equation for IBP (integration by parts)
use the DI method, way easier
No
Okay, you do you
I won’t unlearn it and start using another method
lol u will take less time to learn the DI method than u will take to learn the original IBP equation
Ok, what is Di method?
A shortcut method for IBP
watch a video of blackpenredpen using it
he explains it in full detail
sorry i made a mistake here (incorrectly read the question)
@verbal steppe this should be the final answer, hope this helped lol (sorry if i made a mistake in my solution i tend to make stupid mistakes)
yeah its easy
also this solution is (probably) wrong, its supposed to be e^-x^2 not e^x^2 (for the final part)
That is from a math exam
nvm i forgot to change my incorrect answer to the correct one LMAO
I’d be surprised if it was wrong
yeah it IS correct
no its not
i just forgot the negative sign
@verbal steppe heres the general formula to solve these linear differential equations
Merineth
It’s divided, right?
its undefined
So it can’t be solved?
without special functions? no
if u add the limits from -inf to +inf, then u will get sqrt(pi)
How does he remove -2x?
wdym
yee i dont understand that method, i used my own method i learnt
@opal plinth does the smartest man alive get it? 
i concur...nel is the smartest man alive 
they expressed it in a product rule form?
after rewriting they can just reduce the entire expression to:
,, {\color{green}\qty(e^{-x^2}y)'} = e^{-x^2} y' + \qty(e^{-x^2})' y
kanna
@verbal steppe Has your question been resolved?
What kanna said

Also it's very wrong to say that the integral of e^{-x^2} is undefined
It's complicated but certainly defined
However you don't need that if you want to do integration by parts
Take u'(x) = -2xe^{-x^2}, so u(x) = e^{-x^2}
You have u(x)y'(x) + u'(x)y(x)
The integral of that is int [ u(x)y'(x) dx] + int [ u'(x)y(x) dx]
= int [ u(x)y'(x) dx] + u(x)y(x) - int [ u(x)y'(x) dx]
= u(x)y(x)
= e^{-x^2} y
And on the other side you have the integral of -sin(2x)
@verbal steppe yeah?
I’m here :3
We are just wondering
$\int (e^{-x^2}y)’ dx = -\int sin(2x)dx$
Each and every time we solve this
And put in f(0) = 1
We get that C = -1/2
But the solutions says C = 1
What is going wrong?
Merineth
Do you have the C inside or outside the parentheses
Never mind you shouldn't get -1/2 anyway
What's the next step from this?
No worries
@verbal steppe Has your question been resolved?
Okay i'm back :3
sorry it took a while
$e^{-x^2}y + C_1 = \frac{cos2x}{2} + C_2$
@opal plinth This is my first step
Merineth
Nel
Wrong
Merineth
Right
here
Because it's factored by 1/2
Use 1/2 in this and you'll get the same final answer
Nel, the math god
(well, 1/2 as C2 and 0 as C1)
$xy'-3y=\frac{x^4}{1-x^2}$
Merineth
if i have something like this
i'm having trouble getting rid of the x from the first term
do i divide by x?
$y' -\frac{3y}{x} = \frac{\frac{x^4}{1-x^2}}{x}$
Merineth
Will that allow me to use
Yes
Merineth
Merineth
Yes it can
so when i "move" out -3 i am actually in fact factorising it out from the function?
Yes
It works because of the linearity of differentiation, which I mentioned before, I think yesterday
If you think of the integration as a function f, you have f(-3/x), and because that function is linear, it's equal to -3f(1/x)
Which you can think of as "factorizing" out
\begin{align}
y' -\frac{3y}{x} &= \frac{\frac{x^4}{1-x^2}}{x} \
\text{Multiply with IF:} e^{G(x)} &= e^{-3ln|x|} \
y'e^{-3ln|x|} - \frac{3ye^{-3ln|x|}}{x} &= \frac{x^4e^{-3ln|x|}}{x+x^3} \
(ye^{-3ln|x|})' &= \frac{x^4e^{-3ln|x|}}{x+x^3}
\end{align}
I'm not sure how i use align
\begin{align}
y' -\frac{3y}{x} &= \frac{\frac{x^4}{1-x^2}}{x} \\
\text{Multiply with IF:} e^{G(x)} &= e^{-3ln|x|} \\
y'e^{-3ln|x|} - \frac{3ye^{-3ln|x|}}{x} &= frac{x^4e^{-3ln|x|}}{x+x^3} \\
(ye^{-3ln|x|})' &= \frac{x^4e^{-3ln|x|}}{x+x^3}
\end{align}
Merineth
You need to simplify e^{-3 ln x}
Oh
i didn't realize that could be done
Becuase i'm having trouble on step 4 on RHS trying to do an integral of that
Well, also the x + x^3 is wrong, and even if it were correct, it should have been simplified too
Yeah
You have x^4 / (x (1-x^2))
aaah
i can simplify
hold on let me try!
my best guess would be to
$e^{-3lnx} = x^{-3}$
Merineth
Merineth
Yes
Merineth
$y'x^3 + C = \int \frac{1}{1-x^2}$
Merineth
$y'x^{-3} + C_1 = -\frac{tan^{-1}(x)}{x}+C_2$
Merineth
Merineth
Wait how did you get y'x^3
Merineth
yx^-3
i think i keep making small mistakes like that
but it should be y
and not y'
Still incorrect
Merineth

(yx^-3)' = y'x^-3 - 3yx^-4
Yeah ok
So yx^-3 + c_1 = ...
Integral of 1/(1-x^2) is not -tan^-1(x)/x
No
1 is sqrt 1?
(-x)^2 = x^2
hmm
You can't use that if you have -x^2
$\int \frac{1}{(-x)^2 + 1^2}$
Merineth
So not like this?
That's not what you have
Which one 
$-\int \frac{1}{x^2 + 1^2}$
Merineth
Absolutely not
No
hmm then i'm not really sure how i will utilize the formula
$\int \frac{1}{1-x^2}$
Merineth
this is what i had from the start
$\frac{1}{1 - x^2} = -\frac{1}{- 1 + x^2} \neq -\frac{1}{1 + x^2}$
Nel
Rearrange the terms and find another formula
Merineth
like so
Sure, then what?
I now use the formula
Hmm
$\int \frac{1}{1-x^2} = -\int \frac{1}{x^2-1}$
Nel
You must have a formula that looks like this RHS
I guess you don't
Ok but you can factorize x^2 - 1
(x-1)(x+1)
I retried it
what about -tan^-1(x)
$\int \frac{1}{x^2+a^2}dx = \frac1a tan^{-1}(\frac{x}{a} ) + C$
Merineth
Merineth
.

uh
i'm so confused by what he is doing
i think
i fucked up
I have swapped to -
instead of +
somewhere in my solution
Are you sure it's xy'-3y=\frac{x^4}{1-x^2} ?
Yes i found it..
i accidentally swapped from + to minus
in the denominator somewhere while
solving
it should be 1/1+x^2

i'll redo the whole thing properly ..
brb

Okay
so
C= -pi/4
Is what i got
Can you state the full question?
$y = x^3(tan^{-1}(x) - \frac{pi}{4})$
Yes i will
one sec
$xy'-3y=\frac{x^4}{1+x^2}, y(1)=0$
this was the original
that would be my answer
,w {xy'-3y=\frac{x^4}{1+x^2}, y(1)=0}
Looks ok

Other than a lot of carelessness with signs
i think i'm getting the hang of diff equations

one tiny mistake however.. will cost me dearly..
You'll be better at it than me at this rate
press X for doubt
❌
It would be nice if i could ace one tho
without any help
If i have
$Ae^{4x}-10Be^{4x}+25Ce^{4x} = e^{4x}$
If i understnad it correctly
A has to be 1 in order to get e^4x
but then remains -10Be^4x and +25e^4x
they both have to cancel eachother out
No, you can just divide everything by e^(4x)...
Always try to factorize stuff that has x in it by stuff that doesn't have x in it
i missed the C
Merineth
sorry..
Same thing
i tried doing it alone but i seem to always get stuck when trying to determine A B and C
$A-10B+25C = 1$
Merineth
ofc
What is this supposed to solve?
I tried to solve a diff equation by myself
let me type it up
$y''-10y'+25y=e^{4x}, y(0) = 0, y'(0)=-2$
Merineth
my first initial thought was that this is solved with second order ODE
so i do the y(x) = yh(x) + yp(x)
my answer to yh(x) is
$yh(x)=(C_0+C_1 x)e^{5x}$
Merineth
I'm fairly confident that is right
$5-10
Ok
So then now i just have to figure out yp(x)
so i rewrite it in a way that gives me an idea of how the solution should be
i.e
ohgod
I think i solved it by explain it
Merineth
Happens 
Well in that case there is no B or A either
Merineth
I have this
now i just have to replace y'', y' and y with
what i imagine there to be
y(x) = e^4x
y'(x) = Be^4x
y''(x) = Ae^4x
No you misunderstand
You need to take y = Ae^(4x) because the RHS is of that form
Then you calculate y' and y''
There is no B or C
y' and y'' are fully defined by y (with A)
I'm not sure i understand what you mean by that
f(x) = Ae^{4x}, what is f'(x) ?
4Ae^4x
Right, so that's your y'
Ah
I see what you mean
funny thing is
i wrote that down on my paper
and never actually used it
$16e^{4x} -10(4e^{4x}) +25(e^{4x}) = e^{4x}$
Merineth
Yeah
And now simplify?
I mean you're missing A but that's still true because A=1
where would A be?
.
Merineth
Still missing one
I think i have to repeat this part because i'm not following
i thought i always had A B and C
Not sure where you got that from
the yp(x) part
Is there a method which i can remember by?
step 1: guess what the solution should be?
If the RHS looks like pe^{kx} + qe^{mx} + re^{nx} then you'll have to take y = Ae^{kx} + Be^{mx} + Ce^{nx}
Maybe that's why you thought about A,B, and C
?
idk
I don't know what you're referring to
isn't there a method
or a step by step guide on how to find the particular solution?
in my case
shouldn't it be
i figure out what f(x), f'(x) and f''(x) is
Not that I know of
and then substitute my function with those answers
Isn't that what we are doing?
yeah but there are no variables
the solution is just
f(x) = e^4x
f'(x) = 4e^4x
f''(x) = 16e^4x
after i put those in
don't i just simplify and we are done?
If you put these in and this equation is satisfied, then you are done, yes
But in general that kind of equation won't be satisfied if you just take y = e^{4x} instead of y = Ae^{4x}
(this one is, but it's just by chance - or rather because the one who made the exercise made it so)
So how many A:s should there be?
because when i simplify i get "1"
well i solve the equation but there isn't any variable
i assume that should be A
$16Ae^{4x} - 10(4Ae^{4x}) + 25(Ae^{4x}) = e^{4x}$
Nel
This is what the equation should look like
From there, you solve for A and find A = 1
So you got your y_p = e^{4x}
aaah i see
$y(x) = (C_0 + C_1 x)e^{5x} + e^{4x}$
So that would be my final answer on f(x)
now i just need to put in y and x?
y(x) not f(x)
sorry yeah y(x)
Merineth
Yeah, solve that with y(0) = 0 and y'(0) = -2
what do i substitute y(x) for?
0?
or i mean
if x=0 and y=0
that would give me C + 1
C_0
Yeah C_0
Yes
= 0
C_0 = -1?
Yes
What made you determine it shoåuld be = 0? y(x)
Sorry that was braindead question lol
i get why
hm i tried to solve the f'(x)
I tried my best at least..
woops i tried chain rule on it
With what functions?
$y'(x) = C_1 e^5x+(C_0+C_1x)5e^{5x}+4e^{4x}$
Merineth
Merineth
Merineth
$C_1+5C_0 + 4 = -2$
Merineth
Yes
Merineth
C_1 = -1?
Yes
You already had C_0
You could've put it in here even before differentiating
ohgod i did not realize that
that i could use C_0 from f(x)
;-;

I feel like it's break time but got anxiety for upcoming test lmao

I've been on math since like 14:00
Call chartbit for some hugs 
Do you have the final answer for this?
Yea
Merineth
Well that's not very final is it
Oh i have to give C_0 and C1?
Of course, why else did you calculate them?
$y(x) = (-1 -x)e^{5x}+e^{4x}$
Merineth
,w {y''-10y'+25y=e^{4x}, y(0) = 0, y'(0)=-2}


We wouldn't come back if it truly bothered us
I still have to learn / practice complex equations, integrals and something i don't know the name of
in fact

it has been so long that i can't remember anything from complex equations
There will be a total of 10 questions with 5p each, and i need at least 15 to pass
The past 3 days i've literally dreamt of differential equations
this is awful haha
So full points on just 3 questions?
Seems easy enough if you're careful about silly mistakes
(5) you can do by now
just plug into formula
(5) and (7) is something we have done the past days
A question tho, what the fuck is a hyperbeln
hyperbola i think eng term is
x^2 - y^2 = 1 is the equation of a hyperbola
It's a conic section, like ellipses and parabolas
It's asking about the point (0,1), right?
8. Which is the shortest distance from the hyperbola x2 − y2 = 1 to the point (0, 1)?
Extremely
Well if you can graph the thing it's easier
But then, I'm not sure, maybe just vector maths
No it's squares
You have a point P on the hyperbola, and you want the distance from P to (0,1) to be minimal
That means the tangent to the hyperbola at P is perpendicular to the line from P to (0,1)
Yeah
It means P = (P_x, P_y) such that P_x^2 - P_y^2 = 1
I'm fairly sure this question involves derivatives
Yeah for the tangent
Or maybe you can calculate the distance as a function and minimize it by just finding the min through the derivative
Both ways pretty much as complex
Well you'd need a parametric equation of the hyperbola
If you've never worked with that before, it's not going to be very fun
Yeah i'm looking at the solution right now..
Pretty sure this question is
advanced
I do understand tho that
$d= \sqrt{(x-0)^2 + (y-1)^2}$
Merineth
Is the utilization of pythagoras
Actually this isn't too bad
Once i get started with that equation
Anyhow it's def time to take a break

Thanks for tn nel 

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Hi
Please don't occupy multiple help channels.
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Display an infinite sequence $a_1,a_2,...$ of integers with both of the following properties:\
No term in the sequence is equal to 0\
For all n positive integers, $a_n + a_{2n} + ... + a_{2023n} = 0$
Monkagoras
Could anyone give me a hint on what do I need to know to independently solve this?
Maybe just have it so that each pair cancels like
(1,-1,1,-1,...)
Would that work or is there some limitation
That wouldn't work for n = 2 per example
wait, I think I have misinterpreted the question
nevermind, it wouldn't really work if n were to be equal two
I was thinking of some function in which $a_n = -a_{(2023-n)}$
however as I developed that idea I got to an invalid result
Monkagoras
Think about another way which restricts you further but in a positive way
What if I asked you to make the a_n as simple as possible, for example make as many of the a_n = 1
If I asked you to do this for the first 2023 terms for example, how many of those a_n can you set equal to 1 without having further problems with the conditions you have?
If I have not misunderstood the question I would need to have 1011 or 1012 terms set equal to 1
There is really no way you can set more equal to 1?
I could set 2022 terms equal to 1 and only a single term equal to -2022
In any case, this is basically the strategy I would adopt
The first?
Oh, nevermind, I thought it started at a_0
It would be the last in the case that n = 1
however how could I describe the last term of sequences for other n?
I'll help you a bit further :
Suppose every n non-multiple of 2023 has a_n = 1
I thought about that but if every multiple of 2023 was equal to -2022 it would be wrong for n = 7 as 7 is a factor of 2023
Ofc, you can't have all a_(2023n) equal to -2022
However you can define that sequence by induction
Sorry, I can't really figure it out, I just got to if all a_n = 1 then there would be no such constant sequence because anywhere that I place the -2022 there are infinite numbers which are multiples of that place and got stuck here. Could you give me your resolution?
So my place of reasoning is you just let a_(2023n) = -a_n - a_(2n) - ... - a_(2022n)
OH
I see
that's clever
ty
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hi i need help with this question. am i wrong in thinking when the matrix is raised to an infinitely high power, it converges to a direction of (1,1) and then i should take unit vector of that? can someone show me a step by step of how to do this cause my answer is incorrect and i have no clue what else to do. thanks in advance
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How can I resolve this ?
Raise both sides in exponents to get rid of the logs
First do 2^(everything) on both sides
It is enough to even use the definition of logarithm three times, and the result is already there
Ok thks
I've got the fix and it's the answer, thank you.
yw )
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Let V be the set of all ordered pairs of real numbers. Consider the following addition and scalar multiplications operations on u = (u1, u2) and v =(v1, v2):
u+v = (u1 + v1, u2 + v2) and ku = (0,ku2). Explain why V is closed under addition and scalar multiplication



