#help-0
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Why does 3 come from?
-7i > -21u AHA
Okay then
Both divide bij -7 right
@noble sinew
Or
7i < 21u
Both devide by 7
@noble sinew i <3 u
@abstract prairie Has your question been resolved?
Need response
Send a shot of the problem
me when i invent my own trig indentities
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question solved
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What is the line of greatest slope in a 3D plane?
I think it just means line AE
The point E needs to be chosen on CD such that the slope of AE is as large as possible
@shrewd sentinel Has your question been resolved?
Thx
any further question?
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I need help with 14 i
cry abt it
Wdym? Don’t you get help on this server?
No
I don’t understand
Assuming cos(x)≠0 [presence of tan(x)], what do the individual sides of (i) simplify to?
I’ve tried to turn cos into sin/tan and tan into sin/cos
can you show a pic of your work
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✅
I’ve sent a pic
ℝamonov
Like this?
yes
This is what I got but the answer at the back said it wasn’t the answer.
express those cos in terms of sin
Like cos^2x = 1-sin^2x?
yes
expand and simplify the numerator
For the restrictions, cos(x)≠0
Can you help with question 14 iv?
Notice that you can replace the 1 in the numerator by sin²(theta)+cos²(theta)
Yah I did that
Then, a²+b²+2ab=(a+b)²
How did you get that?
How did the denominator become 1?
Or is it just something you need to know
Oh I crossed it out so it didn’t become a fraction
Oh never mind
I can’t do that here
(a+b)²=(a+b)(a+b)=a²+ab+ba+b²=a²+2ab+b²
I get what you are doing but is there anything that can help me come to that conclusion
Notice that the numerator takes this form.
I get how you did it but I wouldn’t have been able to think about it on my own
It just seems like this method can only be applied to this question but you have to use different methods for other questions that are equally as hard to come to the conclusion of.
Is it just a matter of practice?
Yeah trig identities are mainly just practice, you start to see patterns like turning 1 to sin^2 + cos^2
It’s useful to look at the other side of the equality like if there’s only sins in it then you should change the cos to sines etc
And if there’s numbers you wanna look for factors that cancel to give a number
Practice does help.
Sorry, don't think it is right
You didn't show why sin²(x)-cos²(x)=sin⁴(x)-cos⁴(x). You just wrote it
I thought it just equals to eachother
You need to show steps that take you from sin²(x)-cos²(x) to sin⁴(x)-cos⁴(x)
Notice, $\sin^2(x)-\cos^2(x)=(1)(\sin^2(x)-\cos^2(x))\=(\sin^2(x)+\cos^2(x))(\sin^2(x)-\cos^2(x))$
Euclid31415
Sorry I don’t understand. Also aren’t you only allowed to change the left side?
I am changing the left side itself
Oh ok
I don’t really understand how it can change to that
We went from 1-2cos²(x) to sin²(x)-cos²(x)
Yes. The basic identity sin²(x)+cos²(x)=1
Any questions about these steps?
Yah I have questions on how you used that identity to get that
Notice the result you get after expanding the last brackets
Ok I get the 1= to sin + cod
But
I don’t get how you got two other brackets
Of numbers
What I’m saying is that I think sin^2x - cos^2x should equal to (sin^2x+cos^2x)(sin^2x-cos^2x) I don’t know where you got the rest from
I don't understand. Are you asking why I considered sin²(x)+cos²(x)?
those are equal, yes
Yah but I don’t understand where he got the rest from and how adding the rest will make it equal.
Maybe the more intuitive way to go about (ii) would be from RHS to LHS by factorisation
I’m confused how you added another sin^2x-cos^2x
Yeah RHS to LHS is more obvious for ii imo
I didn't "add" another sin²(x)-cos²(x). I just rewrote it as (sin²(x)+cos²(x))(sin²(x)-cos²(x))
Ohhhhh
I seeee
I didnt see the equal sign
So I thought it just continued
Sorry abt that
And when you simplify it it will equal to the right inside
*side
Thanks
Hope you understand this
I don’t really get what you mean by that. But I get the answer. Also my teacher said never touch the right side.
Then your teacher is leading you astray tbh
There's no reason to only work with the LHS, since equality is reflexive
Well I think it’s because I could solve it by the right side but then I wouldn’t know how to do the left side.
He says the left side is supposed to be harder for a reason
There are multiple ways to show equality. You could manipulate RHS and make it look like LHS or in reverse. You could even show RHS and LHS equal the same expression and use transitivity. Only using manipulation on LHS to make it look like RHS is an arbitrary choice.
The "harder" side is the one that simply looks harder
powers of 4 are generally harder than squaring
Ok thank you.
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So I have this problem here, and ik a simple, "elegant" way of doing it, but how would you do it using the Chinese Remainder Theorem, if applicable
So note that x = 1(mod 2) contains strictly less info than x = 3(mod 4)
Knowing the second means you know the first
You have three unique pieces of info here:
x = 2(mod 3)
x = 3(mod 4)
x = 4(mod 5)
By CRT, this is exactly the same info as knowing x (mod 60)
ok.... so then what? sorry i dont really understand CRT that much, i was trying to do substitutions but it got messy and i couldnt figure it out
The big thing is to realize the correspondence I put above. Knowing a number in (mod 3), (mod 4), and (mod 5) is exactly the same as knowing it in (mod 60)
To actually get this number, you do this:
https://math.stackexchange.com/questions/2441003/using-the-chinese-remainder-theorem-to-solve-the-systems-of-congruences
@void verge Has your question been resolved?
ok
after some time
i got 60l + 59 = x
so how do I imply the congruence of x
with this
@placid zinc
<@&286206848099549185> ?
as in
why is it
x = 59 (mod 60)
whats the proof ig
i think i get ig
oh well
my problem is solved so
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Not really sure how to solve this integral. What I tried doing was letting x=cos(theta) to get 1/sin(theta) dx but didn't know how to proceed from there. Integral is $\int{\frac{1}{\sqrt{1-x^2}},dx$
samarium 62
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Yeah but I don't know how to do that though
You find dx/d(theta) by differentiating
Suppose dx/d(theta) = f(theta)
Then dx = f(theta)d(theta)
Well not exactly
But you can replace dx by that
ok
Should be a standard integral after that
alright thanks
Welcome
oh wow yeah I was overcomplicating it
I don't remember why but I ended up trying to differentiate arcos(x)
Thanks!
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can someone help with this
Yea
ok
tell me when you work out all the angles in triangle ABC and I'll help you from there. Let me know if you need help
ok
ok thx
no worries
i might have a couple more i need help with , ill be back if i need more help
ok
good
do i use the law of sines again?
now you can use law of sines to work out AC and BC
ok yea
you only really need to work out one though
ok
God needs to go back to heaven now, he has some thoughts and prayers to answer
when will u be back
I'll check your working quickly but I have to go soon
all good
bye god
I will respond to all your prayers if you private message me ❤️
ok
(I might not get back to you for 30min though)
its fine i have time
cya
cya
@sterile otter Has your question been resolved?
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a worker has to make 15 products a day to supply the store. He decided to make 21 products a day, so he did his work 4 days early and has 60 leftover products. How much products did he have to do to make his job in time
this problem is confusing.
did you get it from a textbook or homework assignment or similar?
well i tried translating it
translating from what language?
bulgarian
hm
i don't speak bulgarian but i do speak russian. can you send the original so i can see if it's possible for me to figure it out?
uuh idk if u will understand
wait let me try to translate it again i will type here
okok
wait bruh i said 21 but it was 20 sorry for loosing your time the equations is very easy
sorry again for loosing your time
thanks tho
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??

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substruct of 2 upper triangular matrix gives me upper triangular matrix, right?
ping me
@sweet parrot yes, because matrix addition/substraction happens elementwise
in the lower triangular, where we have the zeroes, we'd always calculate 0-0 = 0
assuming both matrices are quadratic and of the same dimension
thank you, another question if i may
is it correct to say that
det(λI−A)=0 == det(λI−REF(A))=0
where REF is reduced echelon form
yes , of course
unfortunately, I am lost on this case, hopefully someone else can answer <@&286206848099549185>
🙏
@sweet parrot Has your question been resolved?
The answer is no. Question is how do I apply ref to it to simplify it bc my matrix is big?
If your matrix is above 3x3 you always use a software to calculate determinant
My problem is that I'm studying software engineering and need to make a code to calculate this
Is there a way to simplify what I said?
The fastest is PLU iirc
what is plu
In numerical analysis and linear algebra, lower–upper (LU) decomposition or factorization factors a matrix as the product of a lower triangular matrix and an upper triangular matrix. The product sometimes includes a permutation matrix as well. LU decomposition can be viewed as the matrix form of Gaussian elimination. Computers usually solve squa...
so my steps will be: (?)
Find ref of A
use LU to solve
det(λI−A)=0
@sweet parrot Has your question been resolved?
@sweet parrot Has your question been resolved?
@sweet parrot reduced echelon form is the form we get after we apply for example gauß-algorithm=
?
In my numerical mathematics course I learned the following
A = LR. I write R instead of U (Germany 🤷 ) for the upper triangular matrix
Let's assume $$ A \in \mathbb{R}^{n\times n} $$ and that we can apply LR onto it.
mrbrown
In A = LR the upper triangular matrix (here R) is the reduced echelon form. We can for example get R if we apply Gauß-alogrithm onto A.
for the eigenvalues we usually start with the equation $$ Ax = \lambda x$$ whereas, $$\lambda$$ is the eigenvalue to the eigenvector x.
mrbrown
Now, let's say we know that A = LR exists then $$ Ax = LRx = \lambda x $$
mrbrown
mrbrown
i will try to mess with it, thank you
$$ LRx = \lambda x \iff Rx = \lambda L^{-1}x $$
mrbrown
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Can someone help me prove this
It's dutch but they want us to prove it using mathematical induction
So proving it for n+1
@tawdry saffron Has your question been resolved?
Ping me when answering
@tawdry saffron
Yes
so you checked for n=1
Yes
I assume you are getting stucked in the third case where n=k+1
Yea
1 sec
Hope it's readable
So that's where I'm stuck
Don't mind me checking for n=4
ok so you have (1+2 + ... + n) ^2 + (n+1)^3 and if we prove that
(1+2 + 3 + .... + n + n+1)^2 is equal to this, we will be done
I don't know how to work out the term ^3
you don't need to simplify that anymore.. the term I wrote below will get simplified to that
so you could assume (1+2 + 3 + .... + n) = m and (n+1) = p
so (1+2 + 3 + .... + n + n+1)^2 = (m+p)^2 = m^2 + p^2 + 2pm
= (1+2 + 3 + .... + n)^2 + (n+1)^2 + 2(1+2 + 3 + .... + n)(n+1)
tell if you understand till here
I understand
yeah and (1+2 + 3 + .... + n) = n(n+1)/2 so replace that in last term. you will get n(n+1)^2 and then take (n+1)^2 common from last two terms
Ruffy🎄
huh
$$(1+2 + 3 + .... + n)^2 + (n+1)^2 + 2(1+2 + 3 + .... + n)(n+1) $$
$$(1+2 + 3 + .... + n)^2 + (n+1)^2 + 2 \frac{n(n+1)}{2}(n+1)$$
$$(1+2 + 3 + .... + n)^2 + (n+1)^2 + n(n+1)^2$$
[redacted]
Ruffy🎄
We weren't replacing that because we had to obtain (1+2 + ... + n) ^2 + (n+1)^3 and we already got (1+2 + ... + n) ^2 , so we aren't disturbing it
so you are done right with proving the 3rd part
yeah
Have to prove this
The same way
Is where I am atm
My n looks like a 4 but it is an n
Yes
so
$$(1+x)^n (1+x) \geq (1+nx)(1+x)$$
$$(1+x)^n (1+x) \geq 1+nx + nx^2 + x$$
$$(1+x)^n (1+x) \geq 1+ (n+1) x + nx^2$$
So ,
$$(1+x)^n (1+x) \geq 1+ (n+1) x $$
[redacted]
\begin{align*}
(1+x)^n (1+x) &\geq (1+nx)
(1+x) \ &= 1+nx + nx^2 + x \
&= 1+ (n+1) x + nx^2 \
&\geq 1+ (n+1) x
\end{align*}
Much better
ScapeProf
$$ (1+x)^n \geq 1+nx$$
Multiplying (1+x) both sides :
$$(1+x)^n (1+x) \geq (1+nx)(1+x)$$
[redacted]
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$\lim_{x \to +\infty} (\sqrt[3]{(x-a)(x-b)(x-c)}-x)$
Ruffy🎄
@tawdry saffron Has your question been resolved?
Try replacing "x" with variable "1/k" where k approaches 0+. Then, you can apply L'hôpital's rule once you bring the k to the denominator. @tawdry saffron
@tawdry saffron Has your question been resolved?
if you end up solving it can you send the solution
im kind of confused as to how to solve that as well 😅
dackid
Yea, this'll work. Multiply the top and bottom by a^2+ab+b^2, where a is the cube root term and b is x
I'm gonna simplify things. Let $u=(x-a)(x-b)(x-c)$.
Then rationalize the fraction like so: [ (u^{\frac{1}{3}}-x) \cdot \frac{u^{\frac{2}{3}}+u^{\frac{1}{3}}x+x^2}{u^{\frac{2}{3}}+u^{\frac{1}{3}}x+x^2} = \frac{u-x^3}{u^{\frac{2}{3}}+u^{\frac{1}{3}}x+x^2}]
dackid
Hope this helps @tawdry saffron
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Why would D be the right answer?
If CB=BA, then aren't triangles CBD and CAE similar, and thus won't Angle CBD = Angle BAE?
Oh, it's asking whether:
(A) Quantity A > Quantity B
(B) Quantity B > Quantity A
(C) Quantity A = Quantity B
(D) Not Enough Information
The triangles would be similar if BD || AE, which doesn't seem to be given
I guess that maybe the answer is D because we don't know enough for it to be similar? Just Googled the similarity rules again (haven't done geometry in a while), and it seems that 2 angles need to be equal, a side-angle-and a side, and side-side-side. Only know 1 side is equal
Oh yeah, ok, got it
Damn I was very quick to naturally assume that they were parallel looking at the picture
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How do i do a
i subbed in c as 0
and gave me an error
so now im confused
.close
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I need to know how can i find the value of [H]^2 in details
,rotate
Thats it?
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I was reading something and couldnt find the exact definition of something;
A typical human fingerprint pattern has a period of around 500 μm, with a width of the ridge ranging from 100 to 300 μm, so the structural parameters were determined to exhibit a ridge width of 100 μm, a period of 200 μm, and a groove depth of 50 μm
what is 'the period' referring to? I assumed statistics but I cant google it properly.
I assume you've done trig?
yes but not in english 😄
@faint lark it's analogous to period of trig functions
it's just how long until it repeats the pattern
(long distance, not long time)
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Hi, so I've been trying to solve this problem: the sum of three numbers in arithmetic progression is 12. The sum of their squares is 66. Find said numbers. My first thought was to somehow translate that into a system of equations and solve it, but I am not sure how to translate it into algebra. Or whether I should use one of the known arithmetic progression formulas and plug whatever is given in
let the arithmetic sequence start at a and have a common difference of d
that's correct
x=a, y=a+d, z=a+2d
so in fact you know one of the numbers has to be 4
So then I replace one of the variables by 4 and solve?
That won't be enough to solve.
You can expand:
(a + d)² = 4²
a² + 2ad + d² = 16
Now, expand your whole equation:
a² + (a + d)² + (a + 2d)² = 66
Then you'll be able to get a multiple of a² + 2ad + d² separated from the rest, and you know that that's 16. Substituting in the 16 will leave you with one variable, which makes that variable easy to solve for.
Just remember that x² = .... has two solutions.
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2-x/3+x = 1/2
basicly what i did was make it into a polynominal with the formula a/b = c/d
by cross multiplying
i got ad-bc = 0
which then i got
2(2-x) = 1(3+x)
4-2x = 3+x
4-3 = 2x + x
1/3 = x
wait what
2-x/3+x is read as $2-\frac{x}{3}+x$
Mosh
well is it (2-x)/(3+x)?
Mosh
then everything you did is correct
okay now next question
sorry not next but a follow up
so when i tried to verify
i plugged in 1/3 for x
and im having a bit of troubles solving..
2 - 1/3 / 3+1/3 = 1/2
what's 2-1/3?
yes.
which is 5/3
yeah
for 3 + 1/3 i got 10/3
yes, so you have $\frac{5/3}{10/3}=\frac{5}{10}$
Mosh
yes
what.......?
.
yes.. division of fractions is multiplication by the reciprocal
however it's easier to just multiply through by 3
oh yeah
then simplify 5/10 into 1/2
ohhhh
so theres 2 ways
reciporical thingy
and multiply by common denominator
now what if we had 5/4 / 9/ 7 what would we do here?
multiply by the reciprocal..
*7/9, yes
gotchaaa
thanks bro
i really appreicate you spending the time to help me
cheers!
Also i used to also play lunar client on minecraft
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can someone help
what have you tried?
x^2018=u
Do I need to tell you that won't help?
is the integrand even or odd?
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✅
Hint: If the integrand is ugly to integrate, think smart not hard
its multiplication how do we know its even
it's odd
I mean after you take integral
is it odd right now in integral?
and recall the odd integrand property and you're done
odd functions on intervals symmetric about 0 will integrate to 0
(assuming bounded interval obviously)
no
god no
you'd have to be able to integrate $e^{u^{1009}}$ or something like that
Mosh
and given $e^{u^2}$ isn't possible
Mosh
isn't possible within elementary functions*
if the 2018 was a 2, then you could
however you'd still get 0, cause it's still an odd function
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u-sub works for xexp(x^2) yeah
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Hello
Will the answer of 11th question be 0?
After doing algebra, I am getting x(6/x + 1/x^2)
As x approaches to infinity.
"No algebra" require you can intuitively see 1/x -> 0 as x -> \infty so you left with 3^2 = 9.
from there you see the limit should be 0, if your not convince you can prove it.
Okay. Thank you 🙂
np.
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Does anybody know whether the partial sum of hyperharmonic numbers has closed solution for not natural orders?
@ebon bronze Has your question been resolved?
do partial sums of harmonic numbers for natural orders have a closed solution? 
Hmm, they do have a solution that gets rid of sum and uses just the hyperharmonic numbers themselves, so yeah
I mean, harmonic numbers are still sums, but that's something
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What have you tried so far
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these are to be done by constructing simultaneous linear equations. anyone know how to begin contructing the equations before moving on to solving them???
Not yet
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@chilly tide Has your question been resolved?
in the first one,
let the number of outback models sold be O, and the number of bush walkers sold be B --> you want to find one of them to find the other, so you need to write equations that link the two. from the first piece of info you have, O = (100% + 20%) * B. from the second piece of info, the profit from selling O number of outbacks is price of one unit * O. do the same for your bush walkers and you have your equations. apply the same process to q16 and u should get the answers
Alright
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hi sam
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@chilly tide hi
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Can someone help please
Are you allowed to use L'Hopital's rule?
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i have a question regarding ii)
im not sure on how to continue
the two attachments are my working up to that point
hint: 0<=A<=2pi
draw a horizontal line y=k, and see how many times it intersects the sine wave in the interval [0,2pi]
y=k is... the line?
when sin(2A) = k, we should have the functions y=sin(2A) and y=k intersect, right?
both works
because those are all lines with -1<=k<=1
ok so lets say the green line is at 1 it intersects the graph 2 times right
but if its in the range it intersetcs it 4 times right
same as -1 it intersects twice
so are my answers 2 and 4?
for the number of solutions i mean
If k=0 then 5 times since you had interval [0,2π]
that's right, but you should also point out how it's usually 4 and there are only special cases where it's 2 or 5
np!
i'm just sam....
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Hello guys
If i want to find a normal vector to a curve f, do i do grad f?
how do you even get the grad of a curve?
I think I might i get it wrong guess
Here is the problem I'm solving
It's number 2
grad of that curve?
iirc gradient is orthogonal to the level curve
So is that a normal vector?
I was gonna find the tangent vector and derivate it
But seems a bit complicated to me hahah
Seems like do grad is the best way
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I know this is very basic question but what operation do I need to know to achieve this?
I have a maxValue and a minValue lets say min=5 max= 50 and i have a third value (x) which represents the point between min and max....
So when x=0 result=5 and whenn x=100 result = 50
What is result as?
“Third value (x) between 0 and 1”
Proceeds to give example of x=100 (third value)
i have a a current height , this height has a maximum and a minimum, with the current height and those maximum and minimums i get a heightPercentage.
Then i have a minVolume=X and maxVolume=Y
I want the volume go from X to Y according to the heightPercentage
like... progressively
proportionally
sorry my math vocabulary sucks
its more understandable?
maybe f(heightPercentage) with max=X and min=Y ?
im sorry my math level is so low
Why do you call it percentage when it isn’t a percentage?
If it was max value it would be 100%
Not equal to max value
mmmm, the height has a min and a max... so taking those and the current height i calculate the height percentage.... i thought i needed this step in order to do the next step
like... lets say minHeight is 2... and height is 2... then heightPercentage==0%
then i would need the 0% progression between minVolume and maxVolume which would be equal to minVolume obviously
makes sense?
If x<=min
f(x)=min
Else if x>=max
f(x)=max
Else
f(x)=x
Is that not what you are saying?
Else it makes no sense
im so sorry... let me explain differently. From scratch
I think he means more like (max-min)*percentage/100 + min
LEts start from scratch:
I have this:
Height values: currentHeight, minHeight and maxHeight
Volume values: minVolume, maxVolume
when current height moves between min and maxHeight i need to assign a proportional volume considering minVolume and maxVolume
does it make sense now ?
c=(max-min)*proportion + max would be the general formula you can use to solve for that
Im not going to use percentages just for simplicity sake
c is current
whats proportion there?
Itd be the thing you want to be equal from volume to height
So youll have one of those fancy equations for height and volume
Lemme solve for proportion so its more useful
c - min=(max-min)*proportion
👀
$\frac{c - min}{max-min}=proportion$
ah thats what i was calling percentage!! sorry im not native
PapaBread
You normally would but in this case you can kinda skip that step
Youll have two of those equations
One for volume and the other for height
With all of the max and mins and currents and stuff
So
$\frac{cHeight - minHeight}{maxHeight-minHeight}=proportionHeight$
PapaBread
$\frac{cVolume - minVolume}{maxVolume-minVolume}=proportionVolume$
PapaBread
aha....
Then you want the proportions to be equal right
yeah this is what i was missing
So you can just set them equal and solve for what you dont know
how?
Uhh
Youd do like
$\frac{cHeight - minHeight}{maxHeight-minHeight}=\frac{cVolume - minVolume}{maxVolume-minVolume}$
PapaBread
That
You know all of the mins and maxes
And you know the cHeight or current height
So the one thing you dont know is the current volume
Which you want to be proportional
yes
It has to be proportional cause we set them equal
So then the next step would just be solving for cVolume and simplifying
Im just going to abbreviate using h and v
ok
$\frac{cH- minH}{maxH-minH}=\frac{cV- minV}{maxV-minV}$
PapaBread
So the first step would just be to multiply both sides by (maxV - minV) right
Then add on minV
$\frac{(cH- minH)(maxV-minV)}{maxH-minH}+minV=cV$
PapaBread
omg 😅
okay
this last equation would do everything without the need of using the proportionns
whats that
Actually it doesnt look like it simplifies much
then its fine as it is?
since i have to code it its ok
@bleak ridge how do you call this? its a simple equation or...?
does it have a name in math?
like... progression.... equation....whatever?
Uhh
hahhaha sorry, i suck at this 🤣
I mean the base equation is linear interpolation
linear interpolation!! thats the name i wanted to google but i didnt even remember
thats what they taught me inn class
(not very well)
Oh
whats this? spam?
no
@bleak ridge thanks a lot 🙏
I dont think youre allowed to advertise here
Np
@bleak ridge
the operation between the numbers on top its a multiplication?
Ye
hehe thanks 🙏
Its multiplying the two sets of subtraction
?
Perhaps
i am dead
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how would i approach this
just a guess but howd ratio work out
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Hello, is there anyone that can send me proof of the abc formula without completing the square? Feel free to dm or to ping
Why do you want such a thing? Haha.
What abc formula are you talking about?
I'm curious
The quadratic formula?
You can also sub the quadratic formula directly into the quadratic, and see it gives 0
the formula to solve ax^2+Bx+c for x
Which is a proof that it works, but doesn't give the quadratic formula
Its a pretty hefty one to prove
Thats why they dont show it when you first learn it
Have you used the quadratic formula? Do you understand how to apply it?
The only formal proof I've seen of that formula is using completing the square, but I think there's a 3b1b video about the quadratic formula which might help you
It's Christmas break and I've got nothing to do xD
Oh without
Yes
Well, you can still always construct the vertex using calculus
I don't know if that's cheating
-b/2a?
Yeye. The vertex is at x = -b/2a
Can get a vertex form, without completing the square to get that form
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I was watching a youtube video and the instructor did this but I don't understand why is he keeping +c when we know the original function, after taking the anti-derivative of the derivative of a function, aren't we supposed to get exactly that same function?
the integral of the derivative is the function up to a constant
derivative of the integral is the function itself
why
I know exactly which function I did it
from
why does it matter
yes
so shouldnt integral of that be 3x + 4
no
When you integrate something, you end up with infinite possibilities that fit the answer
$\int\dv{x}(3x+4)\dd{x}=\int 3\dd{x}=3x+c$
Mosh
It doesnt matter what the original f was
If i integrate something, theres a plus c
Because after you take derivative and integrate you have manipulated the object
- indefinite integrals always have unknown constants.
yeah I'm asking why
cause vertical translation doesn't affect derivatives
so integrating introduces an unknown aspect: Where the graph is vertically
Start from f(x) = 3x + 4
Derivative of that is
f'(x) = 3
When i say integrate f'(x) I'm not asking you what was the original f
Im asking for integral of 3
yeah ok that makes sense
Integral of 3 is not necessarily the original f
It's only one of infinitely many options so you have to plus c there
the derivatives of 3x + 4, 3x - 2, 3x + 1000, etc are all the same
It depends how the question is asked to an extent
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How is a + (b - a) * t also expressed as a(1 - t) + bt ?
a-at+bt
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36 is also an answer choice
I honestly just don’t know where to start
Do you add all the derivatives up and then integrate that?
<@&286206848099549185>
Use ftc?
ftc?
$\int _a ^b f(x) \dd x = F(b) -F(a)$
jan Niku
for appropriate functions
$\int _0 ^6 f'(x) \dd x = f(6) - f(0) = 2 - (-22)$
jan Niku
Wait so it should be negative 24
