#help-27
1 messages · Page 277 of 1
Tbh when ppl speak french, i don't really watch the grammar or whatever, i assure you are speaking it well
You made two little mistakes (add/forget a letter) in both messages
Which change nothing to the meaning
@restive river Has your question been resolved?
You can use that f(x) = f(x/2)
I have no idea what this is
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Can someone walk me through the steps on how to solve this
Are you using quadratic formula or factorization to solve it?
which one?
Like ik there's different ways to solve it since it's a quadratic ewuation
Which
Either way works
12
Which method do you prefer
Im not sure i haven't done much practice probably using the quadratic equation
Discriminant will work as switz watch
So theres a formula for quadratic ecuations
Which is
Ok, so first you will get a, b and c (the coefficients)
Try making this using a,b,c
x2 + 5x -24 = 0. Do you agree?
Ohh shit right
now we can get the a, b and c values
Should I make it become x²+5x-24=0
yes
You should firstly equal the equation to zero
Yes
a = 1, b = 5, c = -24
Ok and I plug it into
Make him think man 🙂↔️
The quadratic equation
yep
-5+-sqrt
Hold ob
Ye
Now what you need to do
reduce
Now what do you think you should do now
Er idk the word but do I multiple the -4(1)(-24)
Multiply
You could
I would recommend firstly doing
5^2
So 25
Sqrt of 121?
11
👏
Ye
But normally just leave it
OKIESSS
What's this for 😭
For (10-x)^2
Is x not 1 😭
Your x is one line
Ope
Bc im silly 
Now just do all ^ and multiplications
Btw all this =-25
Dont forget
Youre doing the ecuation
Not just (x-10)^2
Nvm
Gotta go take the shower
LOL okk
🫡
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Since 0
is a possibility for oranges and for apples but not for both. we have
(9 + 1)(6 + 1)- 1 ways" Is the solution as described in the answer key, can anyone explain this to me please?
the easiest comparison for me is with factors of numbers
I understand that 0 is not a possibility for both, however the formula that follows is new to me. What is the reasoning?
this
if we have a nukber
a^3 • b^2
how many factors are there?
the rule is
(3 + 1)(2 + 1) or 12
you either have the factor in or you dont
same idea with the fruit
No, I still don't understand
uhhh
okay the fundamental theorem of counting says
if you have m ways to do one thing and n ways to do another
there’s m • n ways to do both
do you agree with me
yes
okay
in this scenario
you can pick 0-9 oranges (10 options) and you can pick 0-6 apples (7 options)
so then 10 • 7 ways to pick the fruit
understand to here?
alright
last thing is that
there is a case where you pick neither of the fruits
so you have to subtract one
thus (9 + 1)(6 + 1) - 1
ah, I thought the -1 was because you include zero in both cases, which can't be right since the requirement is at least 1
it is?
alright
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i have a question that is NOT about math
however
you are all smart people
so
how does asexual reproduction work in angiosperms
actually nevetminf
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How would you solve this?
How do you mean? I know you have to work out the gradient of line B
But I’m not sure how
It’s just the slope of the line - rise/run
That’s what I need help with working out the gradient
How can you just eye ball the gradient?
which one appears most tangent
it should stay close to the function
it shouldnt come in at a wonky angle
or pull away too quickly
I don’t understand
I think your talking about the line
I’m talking about how you work out the gradient of line B
Well you need to do ur fuckin job and tell me the answer
@feral ledge Has your question been resolved?
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me and my friends have been debating whether if the 1 at row 0 is to be isolated or to be grouped with the 1 at row 1, whats the case here
( im new to kmapping and this confuses me )
( internet modules tell me that its to be isolated, while my friends have been telling me that i should be grouping it )
It's better to group it
So it reduces more
but its still fine to isolate it?
It's not going to be the most reduced expression
ah so its for the expression to be in its most simplified form?
Since you isolated it, you have x'yz but if you group it, you'll get yz
That's what a kmap is used for, to reduce to most simplified form
Which?
Yes that's to be isolated
As a rule of thumb you want to make groupings in the size of 2^n
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please help me find d(x+s)/dt
@serene dragon Has your question been resolved?
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so this is my answer how to determine the truth table
the number 2 is wrong tho, my real answer is
r is false, s is false = false v false is false
q is true, so false <-> true is false but "~", so TRUE
r = false, so true -> false is false
so its false
how do i change the words into the symbols like on the number 4. T T F F T F F = False
idk what its called but i just call it symbols
@hoary osprey Has your question been resolved?
<@&286206848099549185>
apologies for my ignorance but whats your question here
So here is my answers right
uh huh
here are the examples and look at number 1 and 4
they have this kinds of symbols? im not sure what its called
T T F F T F F = False
How do i get the symbols of my answer
i see
oh wow the book just kinda goes random with its truth value labelling
yes it is
then just do however you want
make a truth table if you want
maybe something like this idk
^
works too if you can understand it
correct me if im wrong, my answer on number 1 should be TFFFTFFTTF

cuz thats my answer on my truth table
yeah sure
usually i dont write the original and the negated together
but its whatever
could you check my answer on number 1?
what would be your answer on number 1?
mine would be TFFFTFFTTF so its False
yeah its false
I see
I get it now
I believe that’s all I need for now.
Thank you so much for your help, Shioshi.
Thank you so much for your time and help
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i forgot what the addition method entails
if a = b and c = d
then a + c = b + d
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yeah the 2.5 shouldn't be there
$e^{\int 0.4 \dd{t}}$ ain't the same thing as $\int e^{0.4 t} \dd{t}$
aPlatypus
the second one is indeed e^0.4t / 0.4
yea
the e^0.4t/0.4 is wrong
it is
thank you!
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From point A, which lies outside the circle (O), draw two tangents AB and AC to the circle (O) (B and C are the points of tangency). The ray AO intersects the chord BC at point H, and draw the diameter BK of the circle (O).
Prove that ∠ACD = ∠HKB.
Given data:
• OA is perpendicular to BC, and OA is parallel to KC.
• AK intersects the circle (O) at point D.
• Triangle ABK is similar to triangle ADB.
• Triangle BDK is a right triangle.
@fathom harness Has your question been resolved?
abk is similar to adb helps solve it
Can you explain it
My teacher said that the tip is proving 4 blueish angle is equal
nvm i was on something
<@&286206848099549185>
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can someone explain how did our equation 2/s^2+4 got simplified to tan inverse
It didn't get simplified, they took the integral
@obsidian nebula Has your question been resolved?
we will take 2 from nominator and 1/2 out from the denominator in equation which will leave us with 1/s^2+2 to integrate right?
nope
can't pick and choose which part of the denominator you want to pull out a 2 from
ya exactly
do you know how to integrate 1/(x^2+1)
ya thats tan inverse x
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Translation:
Let x be the result of the following operation (image above, line 1). Decide if the following statements are true or false.
- x is less than 1000
- x is not an integer
- x is an odd number
How do you solve thin type of question? I have no idea where to begin.
Try writing every term in parentheses as a single fraction
1+1/2=3/2
1+1/3=?
4/3
I'll see what I can come up with
After doing that nearly everything cancelled out and I got x = 1006, so I guess it's solved
Thanks for the hint
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Guys...
If I have something like 2*(x+1)^2
Yeah, I get 2x+2 * (x+1)
NOW.
Do I multiply 2*(x+1) or
(2x+2)*(x+1)
????
The second
Ah yes?
What's the reason behind it tho?
There's parentheses there in any case, not writing them is what's confusing you
2(x+1)^2 = 2(x+1) (x+1) = (2x+2)(x+1)
Wait so
Parentheses never leave after you multiply?
WHAAAAAT???
They leave when it's unambiguous, but as you've written it above 2x + 2 * (x+1), the order of operations would stick with 2x+ (2*(x+1)) if you don't have parentheses. That is not the same as 2 (x+1)(x+1)
FUCK.
Now my exercise is correct.
FUCK yeah!
What do you mean when it's ambiguous
Any rule master?
As a rule of thumb, if you're multiplying by a single constant, no parentheses. If you're mulitplying other things, keep the parentheses. It'll be clear if you don't need them
So 2(x+1) = (2)(x+1), but we don't need the parentheses for 2
(x+1) * (x+1) we need them since order of operations would induce the wrong interperetation if we just write x+1 * (x+1)
Why tho?
I don't get it, fuck.
Why is (x+1) not the same as x+1(*(x+1)
It's the order of operations.
In x + 1 * (x + 1), the "correct" way this is parsed is that we start with multiplications, and then move onto addition.
So in other words x + 1 * (x + 1) = x + (1 * (x + 1)) = x + (x+1) = 2x + 1
(x+1) * (x+1) is parsed as you would expect as
(x+1) * (x+1) = x^2 + x + x + 1 = x^2 + 2x + 1, which as you can see isn't the same as above.
When in doubt, just put more parentheses to ensure the operation you're writing actually corresponds to what you mean
Well, I was doing this exercise so
Gotta find second derivative, y'know
yeah, and when I added parentheses it started to work.
Then again @trail eagle
when am I supposed to leave the parentheses?
what do they affect?
@hexed berry Has your question been resolved?
@hexed berry Has your question been resolved?
whats your question
Based pfp, a man or woman of culture I must say.
When do we remove parentheses?
thank you
whats the orignal question
i really dont wanna
read all of that
text wall
Of course
what is it
F'(x)*g(x)-g'(x)*f(x)
Because we gotta use quotient rule?
you can bring
the denominator
to the top
and just make the exponent -1
than just do the power rule along with the chain rule
Yeah but like
my dumb cirno intelligence
won't let me try that during test
you smart me cirno
what
you basically have to do this
unless u want a crazy long quotient rule
but they probably wont even accept that
Thank you diamond
Based pfp ans based brain
Based face too probably
no problem 👍
What do you think about your pfp
what
what do you mean
what do i think
about my pfp
lol
if i didnt like it, it wouldnt be my pfp
@hexed berry Has your question been resolved?
how has your question
not been resolved
bruh i got no idea what emilias nails look like 😭
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i just know the character
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Are there any good strategies in integrating functions like 1/(x^4 + 1), cscx, 1/x^5 + 1) etc
umm like what exactly id use different methods for each of those integrals
integration is a case-by-case process
yep adding a single thing to an integral can make its ideal approach entirely different
also like the integral of 1/(x^5 + 1) is nasty
Thing is, there is no clear technique that you can use in integrating those kinds
csc x is not hard
oh so you are asking about the little tricks you can use to make them easier?
Kind of
Integral of 1/(x^5+1) evaluated using complex numbers, the cover up method, and clever reorganization of terms.
Join my discord: https://discord.gg/uqUEJmhmG7
Feel free to suggest integrals or other problems for me to try in the comments!
Like and subscribe if you enjoyed the video and want to see more content like this!
Thanks for watching!
you know all about u sub, trig sub, that kind of stuff?
Yea
Is that seriously the integral
That’s wild
Good thing integral sheets exist for a reason
you u sub after
Yea that's doable, but like how do u know what to manipulate it into
The only thing ik is u have to do lots of trials and errors
ill just say it how i heard it
you learn to "smell" it
when you do a lot of integrals you just look at it and feel like you know what goes next
what we can do now for you is show you a lot of different tricks to manipulate the integral into something more familiar
we cant really "teach" you exactly what to use because integrals are built on a case-by-case basis
yeah it's impossible to really come up with methods on your own
all you can do is look at other questions you've done and try to see if you can apply the same methods
The integral of sec(x) has a pretty interesting history. It has a whole Wikipedia page.
I realise this is unhelpful for OP, but for the trig ones like $\int csc(x) dx$, my teacher just told us to memorise them
luna-maia
Than who invented u sub if it’s impossible 🧐
there can only be so many methods discovered before it's just renaming an old one 😭
Well those other questions, thing is those have an obvious technique u can use
I lokey be praying sometimes that I can invent the math my self on tests
But nothing is impossible
Who knows
Newton and Leibniz I'd say
u-sub is just the chain rule in reverse
Reverse chain rule
While these kinds u have to do lots of manipulations to find an equal expression that is doable
starting out with $f'(g(x)) \cdot g'(x)$, you can integrate that
southlander!
welcome to math
also there can be many different forms for the same integral
Yea but in the first place, how did they find an equal expression for it that is integrable
Was it trial and error
MIT integration bee math tricks just search something along those lines on yt
I assume it's just Riemann summ and they find some cool e function?
e
for instance this https://math.stackexchange.com/questions/333611/evaluating-int-frac1x41-dx
how did they find an equivalent expression for it
trial and error?
just use partial fractions
is it factorable?
yes
there is a note below the answer, point 1
add 2x^2 and subtract -2x^2
then complete the square and then difference of two sqaures
...you just do
it's hard to come up with it by yourself
Like honestly idk what to tell you
maths is a very very old field
chances are whatever you do, it was probably done by some guy hundreds of years ago
especially at a pre-research level, so like all of undergrad and before at least
uh what so those guys already know what to do already?
No I said that they just do know how to come up with these solutions
They have the knowledge to advance and they know how to use it
And they do, so in a sense yes they know how to do it, if the question was posed differently
so no trial and error?
Not sure what you even mean by trial and error
Keep changing the functions until it looks integrateable?
yes
Well they do that I guess
Or they could also just imagine a function that's integrateable, then try to find a way to make it look similar
That's basically ODEs
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Can anyone help me with time series ?
I have this tables
what model should i choose based on this ?
My goal is to forecast microsoft stock prices
btw my english is not the best
The automatic model and ARIMA(1,1,1) with drift have the lower AICc , but in the other hand they have one of the highest RMSE , how can this happen ?
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Can someone help? I'm trying to calculate the Daylight Factor (DF) at point X, but my result is consistently at least 2.5% too high. I need it to be below 5% to align with logical expectations
Window Dimensions: 2 meters wide and 2 meters high.
Reference Point (X): 0.8 meters high and 1 meter away from the window.
Obstructing Building: 6.2 meters tall and 6 meters away.
Calculating the Obstruction Angle:
𝜃=tan−1(6.2−0.8/6+1)≈39.8∘
Calculate Ratios:
𝐻−𝐻𝑥/𝐷+𝐷𝑥= 6.2−0.8/6+1≈0.77
𝑊/𝐷+𝐷𝑥= 2/7≈0.29
Using BRE Tables:
Finding the intersection of these ratios to get the SC value. Assuming SC value of 0.05
ERC: 𝐸𝑅𝐶=𝑆𝐶×brightness or reflectance = 0.05x0.1 = 0.005
IRC: Using BRE tables to find the IRC value. assuming IRC value = 0.02
𝐷𝐹= 𝑆𝐶+𝐸𝑅𝐶+𝐼𝑅𝐶= 0.05+0.005+0.02= 0.075
Converting percentage : 𝐷𝐹=0.075×100= 7.5%
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Im not sure where im going wrong here. I need to use stokes' theorem
the four points are on the plane z=1/3 y
a parametrization of this is r(u,v)=u i + v j + 1/3 v k
curl (F)= 10y i +2z j +4y k, which in terms of u and v is 10v i + 2/3v j +4v k
the two derivatives of r(u,v) are i and j+1/3k, the cross product of these is -1/3 j+k
the dot product of curl(F) and this cross product is 10/9 v
integrating from 0 to 3 with respect to v and then 0 to 3 with respect to u gives 15
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@slate obsidian Has your question been resolved?
The dot product of curl(F) and |r_u(u,v) cross r_v(u,v)|sounds wrong
The k component is 4v * 1 and that's already larger than 10/9*v
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How do you integrate this problem?
I have been watching Organic Chemistry tutors video on how to integrate these types of problems, and he does not have an example like this in the video. He has something similar, but I dont know how to integrate a problem like this.
<@&286206848099549185> '
just separate the fraction?
$\int\frac{7x^2-9x+3}{x^2}\dd x=\int7\dd x-\int\frac9x\dd x+\int\frac3{x^2}\dd x$
ok did this. Im confused on what to do for the 3/x^2 though? do you just leave it since there is no x on the top?
and afterwards is that the answer plus c?
bruh
you can integrate it like u integrate any other x^n you add one to the power and divide by the power
except the power is -2
is that not what I did
no thats not what you did
Ok so id start by saying its better to simplify your x terms before you integrate
wait im reading the wrong thing oops
so the first issue is you've accidentally done 7x^2/x^2 = 7x so when you integrated you got 7x^2/2 which would be correct if you were integrating 7x but you're integrating 7
its 7x^3 in the original. my handwriting just bad
oh
then yeah thats correct
but the 9/x term is a special case
9/x = 9x^-1
if you add one to the power you get 9x^0
it actually integrates to 9ln(x)
so that one you just have to know
does that apply to the 3/x^2 too?
not quite
3/x^2 = 3x^-2
if you add 1 to -2 you get -1
which is fine
you can do it normally
$\int \frac{3}{x^2} \dd x = \int 3x^{-2} \dd x = \frac{3x^{-2 + 1}}{-2+1} + c$
I can't believe you've done this
ill get it right eventually
thats how you do that integral
so you should get $$ \int \frac{3}{x^2} \dd x = \frac{3x^{-1}}{-1} = -\frac{3}{x}$$ using negative powers
I can't believe you've done this
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Two textbooks are selected at random from a shelf containing three statistics texts, two
mathematics texts and three engineering texts. Denoting the number of books selected
in each subject by S, M and E respectively, find (a) the joint distribution of S and M
this is my jpdf
it doesnt add up to one
when i look it up online
(x=2, y=2) has a value which i dotn think is possible
and (x=0, y=2) has a different value than mine which i think is wrong
what are x and y?
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x is random varible for math tb and y in random variable for stats textbook
you found out
the question says M and S are those random variables but alright
show me the calculations you did to get those numbers
now we reach the crux of the problem. That calculation is missing something
that assumes that you pick a math textbook and then a stats textbook; that's not the only way to select one of each
indeed it is
yeah...
so you can get 1 math and 1 stats book by picking a math then a stats OR a stats then a math
how does one normally handle OR when computing probabilities?
addition?
quite so
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can some1 help with b)
i think im tired but i keep getting it wrong
ik -5pi/12 is -75 degrees = -45 - 30
so
tan(-pi/4 - pi/6)
and then u start the identity
use addition formula for tangent
since u already have tan(-pi/4 - pi/6)
denominator is +
or do i just add a negative at the very end?
^ this
but
it’s 1+
it’s always opposite the sign of the operator in numerator
so how do i do with plus?
tan(pi/4 + pi/6) ?
thats just weird tho bc it gives positive 5pi/12
if u mean only here
if ur confused u can also write
tan(-5pi/12) as tan(7pi/12) which is just tan(pi/3+pi/4)
and then u dont have 2 negatives and u wont be confused
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For (3) I concluded that this is only possible if
$$ \int_{-\infty}^{\infty}x(t)\left[\cos(\omega t)\sin(\alpha \omega) - \sin(\omega t)\cos(\alpha\omega)\right] = 0 $$
if you take $\alpha = \frac{k\pi}{2\omega}$ for some integer $k$ then you're left with an even multiple. But is my thinking correct overall?
Aero
To be clear, the notation above is describing [x(t) \xrightarrow{\mathscr{F}} X(j\omega)]
where $j = \sqrt{-1}$
Aero
@sand quarry Has your question been resolved?
@sand quarry Has your question been resolved?
@sand quarry Has your question been resolved?
@sand quarry Has your question been resolved?
@sand quarry Has your question been resolved?
yes
i believe so
Issue is: kpi/2omega doesn't make much sense in my mind
alpha is meant to be a constant I presume
but we are making it depend on omega
.close
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given this system,
1)they ask us to find the rank of this system
2)and then determine the principal matrix and the principal equations and the principal var of these ystem
3) Rouché-Fonténé Theorem to give the neccessery and sufficient condition on and b for the system to be consistent (specify the determinant bordering the principal determinannt)
4) solve the system if it consistent,
for the rank i wanna use REF
so what i know is that to find the principal matrix i need to find the rank of the matrix, and then those equations will be the equation of my matrix (independent equations)
and then put them as principal equations
for Rouché-Fonténé Theoreme, based on my understand it's say that:
if the rank of (A) = rank(A |b ) < n the system is consistent, it's have infinite solutions
if rank(A) = rank(A |b) = n it's the system is consistent and have only one solution
if rank(A) < rank(A|b) the system is unconsistent and don't have solution
and then for question 4 i believe the system is consistent based on the value of a and b, so i just reply with that value and solve the system
do i'm doing anything wrong?
@simple canyon Has your question been resolved?
<@&286206848099549185>
@simple canyon Has your question been resolved?
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am i right with D here?
It's wrong
Show your workings like you did the last
im srry i mistyped i meant D there
You chose B though
damn man its on paper for this
😭😂
its random
i picked b there then typed it on mistake
It's D that's correct
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Question: If two nxn matrices A and B over a field F have all four of the following being equal to each other, must A be similar to B?
Characteristic polynomial of A
Characteristic polynomial of B
Minimal polynomial of A
Minimal polynomial of B
Prove why or give a counter example.
My thoughts: I think the answer is yes bc I really can't think of a counterexample. I found 4x4 matrices that both had characteristic polynomial x^4 and minimal polynomial x^2 that had different JCF so weren't similar but then I realised the characteristic polynomial had to be equal to the minimal polynomial so that wasn't a counterexample.
@half cargo Has your question been resolved?
If the characteristic polynomial for a matrix equals the minimal polynomial that tells you a lot about the kind of Jordan blocks you have as you already saw. Namely that each eigenvalue can only have a single jordan block
I think that because you get eigenvalues and algebraic multiplicities from the characteristic polynomial and the size of the largest Jordan block corresponding to an eigenvalue from the minimal polynomial
That means that they must have the same JCF and are therefore similar?
Or am I mistaken
Like they have to have the same eigenvalues and block structure?
Thats the big picture idea, but Im not sure how precise you are expected to be
Yeah I have no idea how to make it more precise haha
If every eigenvalue can only have 1 jordan block, thats a very strong restriction
Yeah very true
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Why'd you delete
oh ok let me reopen
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im very lost on the second part
because 2/7 x + 3/7 y = 3/2 x + 4y you get that y = -17/50x
and so you can plug that into the constraint to find the x value at which a critical point occurs
how did you get the fractions
divide Fx by 7
and Fy by 2
you're just solving Fx and Fy for lambda
so you can equate them
is it kinda similar to finding the critical points where you have to zero out a variable?
wdym by that
ok nvm lol
it's similar to optimization in calc 1 right
i dont remember that lol
ah i see
it's way too tricky to optimize two variables at once
so the better idea is to get your variables in terms of one
gotcha
lagrange multipliers guarantees you whatever relationship comes out of Fx, Fy and F_lambda will give you a critical point
often times you want to solve F_x and F_y for lambda so you can relate them together
👍
yeah
ok cool
the better way to htink is you can say you're solving for lambda
what happens to the other symbol
does it cancel out?
how come its not there when its solved or in the simplied part
these are solutions to a review so this is the profs work
the work is a little misleading sort of
dolphn
your goal is to solve this for lambda
that the wishbone sign right?
yeah
ok
$2x + 3y = 7\lambda$
dolphn
yeah that makes sense
so you'd want to do the same for Fy
im confused as to why the thing is inside the equation
lambda?
yeah
ah i see
the method of lagrange multipliers introduces lambda
to find the lagrangian, you use your objective and constraint functions
if you have one constraint, the lagrangian F is equal to $F(x,y,\lambda) = O(x,y) - \lambda C(x,y)$
dolphn
where O is your objective function and C is your constraint
in this case O is given to you straight up right
f(x,y) = x^2 +3xy + 4y^2
ok i got what the equation is
so the lagrangian introduces this lambda
and we want to look at Fx = 0, Fy = 0, and F_lambda = 0
and relate them together
the best way to do this in most cases is to solve F_x = 0 for lambda
like we did above
and we can also solve Fy = 0 for lambda
im sorry im so lost
it's all good
does it make sense how we construct F
let's just like imagine we started from the beginning
yes
okay awesome
now the method of lagrange multipliers specifically tells us we want to look at Fx = 0, Fy = 0, and F_lambda = 0
yes
so we take our partials and we write those equations down
now we want to somehow relate these equations to eachother
the best way most of the time is to solve Fx for lambda, like we did above
which gave us 2/7x + 3/7y = lambda
now we can also solve Fy for lambda right
yeah its 3/2 x+4y
3/2x + 4y = lambda right
yeah
that implies taht 2/7x + 3/7y = 3/2x + 4y
because they both equal lambda
yep
now this tells you that y = -17/50x
you could ahve chosen to solve for x aswell
you just want it nice and simple for when you substitute back in
well im trying to figure out how -17/50 got there
ah i see
they're just using 2/7x + 3/7y = 3/2x + 4y and solving for y
that's why we wanted to solve Fx and Fy for lambda
so we got a new equation that we can work with
yeah but im confused what they plugged in to get -50/17
or the other way around lol
they're just re-arragining 2/7x + 3/7y = 3/2x + 4y
like subtract 2/7x from both sides
subtract 3/7y from both sides
our goal is to get a relationship between y and x so we can substitute into F_lambda
that's where we get rid of an extra variable, in the F_lambda
we can't do that right now until we simplify this equation more
vice versa
we know that F_lambda is 7x + 2y = 30
but htis is really annoying because it has two variables right
so we want to find a way to make it into only one variable
oh my lord
this is so messy lol
im tryna get some boba lol why do it gotta be s complicating
from our work above we know that 0 = 17/14x + 25/7 y right
so true...
optimzation is always messy
so -25/7 y = 17/14 x
so -50y = 17x
so y = -17/50 x
multiplied this line by 14
14 /7 = 2 so 2 * -25 = -50
i think im brainfarting
is there a way you can show me on a paper on how you did it
yeah
thank you
$(14) \frac{-25}{7} y = (14)\frac{17}{14}x$
dolphn
$(2) (-25) y = 17x$
dolphn
because 14 / 7 = 2
now we have gotten something REALLY convienent to substitute into F_lambda
youre amazing
its crystal clear now
thank you
do you think i can dm you if i need help again
cuz you actually help me understand the concept
sure
i dont know how long ill be on for but yeah
most of these will be the exact same approach
it's just the derivatives might look uglier etc
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We're given the col space of A in R3x3
we're given Y0 and asked to find alpha such that AX=Y0 has a solution
did i solve this correctly?
the solution would have to be included in the col space of A, right?
@primal jolt Has your question been resolved?
I'd also like to know if I solved b correctly
b) Find all solutions of the system AX=(1 1 0)^T
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if y1,y2,y3 are known particular solutions to a nonhomogeneous diff equa, define y(x) = k_1 y_1(x) + k_2 y_2(x) + k_3 y_3(x), then If k1+k2+k3=1, then y is also a solution to the original differential equ?
@void knot Has your question been resolved?
plugin y in your diff equa and look if it is fulfilled.
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please assist. What can I do besides turning it into polar coordinates?
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Determine with the help of these points an approximation to cos(127 deg - 53 deg) and sin(53 deg+53deg)
Is the question formatted wrong because the answer is in decimals and I dont think theres a way too do that with just the image?
It's a unit circle.
So your coordinates would be (cos53, sin53) [blue one] and (cos127, sin127) [red one]
Now use cos(127-53) = cos127cos53 + sin127sin53
yeah I understand that you use this . but since the question is asking with the points but I dont see how they are relevant
Do you know that the x-coordinate represents cos and y coordinate represents sin on unit circle?
i mean like is the image even relevant to solve it
How'd you get coordinates and angles without this image?
I mean cant you just use the formula on this without an image
if you use the formula,
You get something like this as LHS; cos127cos53+sin127sin53.
You wouldn't know the value of cos127, cos53, sin127 and sin53 without this image.
ah. i think i get it
sleep deprivation is real. you get the values of them then multiply them at the end
If you do directly cos(127-53), you get cos(74) on RHS.
which is equivalent to sin(18).
You could use sine table but you're required to use trigonometric formulas here.

