#help-49
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Jonath A.K.A Planned Aiphid1621
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you know why
@oak ether
you should not and is not allowed to use bot to help
ill delte
nd ur literally giving the answer away
π
anyway
no ur supposed ot guide me through it
oops
yes
oki
but do you know any property for determinant of product and inverse of matrices
ok which ones do you know
yh
ok can you list it out just to be sure
list out the things i know?
just the ones that you think is enough for this question is okay too
so what is det(AB) in terms of det(A) and det(B)
just multiplyright π
ohh wait so i need to find the det of both then multiply the result by each other
what about $det(A^{-1})$ in terms of $det(A)$
lgkoo
yes, except in the question it contains inverse of A, and transpose of B
oh inverse im not too sure π’
lgkoo
is that the transpose
yes
yeah im kinda lost sorry π
i need to find the inverse right
before the transpose
you don't
from this we know that det(A^-1) = 1/det(A)
so as long as you know det(A)
you don't need to find A^-1 and its determinant
so it would A^-1 = 1/det(3x-24)
yes
which im not too sure of tbh
oh
the determinant of the tranpose of a matrix is the same as the original matrix
wait so its just det(B)
yah
nah it's ok, you're still learning
last thing
do you know what's det(kA) in terms of det(A)?
where k is a scalar constant
uhh
(in this case for the question k = 5)
im not too sure sorry
det(kA) = k^n det(A)
where n is the dimension of A
in this case A is 2x2 so n = 2
btw I would suggest you spend time to verify these formulae yourself too
im tryna process it xD
yh that's good
im kinda confused on how its 2x2
ok, so combining these formula
yes
ohhhh
now can you do it for the question?
yup, so what would you get
i dont really have a calculator on me rn π
you don't have a paper to work on?
i found one its fine
nvm it doesnt work π
ill just use a paper
OKAY i think i got it
is it 154/3
nvm
wait
i think i made a mistake
for what though, the determinant or x?
show me your work and we can figure out the mistake together
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why is the unit normal vector N (times dS) equal to that?
the oval is the intersection of the cylinder and the plane 2x+2y+z = 3, which means that the oval is on the plane
so it has the same normal to the plane 2x+2y+z=3
gotcha, thanks!
np
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!1c
Please stick to your channel.
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58.03 I guess
12.8 / 4 = 3.2 meters (base side)
Base area = 3.2 * 3.2 = 10.24
V = 1/3 * 10.24 * 17 = 58.026666666... ~ 58.03
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Looking for help on where I went wrong for this question
How did you determine your a and b
Also, you did not account for the inner radius in your setup
@latent hamlet Has your question been resolved?
Did you try drawing a graph?
graph would just be a wider parabola right?
no I don't think I did, I haven't done calc in over a year and have forgotten a bunch of stuff
Do you recall the Washer Method?
yea a little, also I'm realizing my a and b should be +/- 1.308 right?
oh yea yea so it's +/- 1
With the Washer Method, you subtract the volume calculated by the inner radius from the volume calculated from the outer radius.
ok yea I'm remembering, so outer radius is Ο(x^6)^2 right
Which is ΟR^2 - Οr^2
Not quite. The radius needs to be calculated from the axis of rotation.
What is that distance?
What is the distance from the axis of rotation to a point anywhere on the curve y = x^6 on the interval [-1, 1]?
How would you calculate that length?
integral of Ο(x^6)^2 ?
No.
Consider the points at the ends of the orange line segment. Let's say at x = 0 to keep things simple.
yea that's 5
What are the coordinates of the endpoints of the orange line segment?
5 and 0
The (x,y) coordinates.
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β
(0,0) and (0,5)
And how would you calculate that length?
ahem Distance formula, but you don't worry about the x value because it would zero out.
it's just 5 yea?
its 5 units
At that particular point, but that's not what I'm getting at.
How would you calculate that distance using the distance formula?
0-5 = -5 ?
Would it make sense to have a negative length?
So what do you think you should do?
5-0=5 ?
Yes. ALWAYS subtract the smaller value from the larger value to get a positive radius.
At any point on the curve y = x^6 on the interval [-1,1], the y-value will be less than or equal to y = 5.
Okay, so now what do I do with that
Now let's think in more general terms for calculating the length of the radius.
Alright
this is where I'd want to use an integral right?
Not yet. I'm teaching you something rather basic right now before we get to the integral.
5-f(x)
And what does f(x) equal?
the y value at a given point of x
What is the equation given to you by the question?
x^6
so 5-x^6
Now let's find the inner radius using a similar method.
alright bet
How would you calculate that radius?
5-1
Correct.
So the Inner Radius is equal to 4.
Now you can fill in the integral for the Washer Method.
Yes.
And there is a reason why I emphasized using the Distance Formula. There will come a time where you will to need to solve for the rotation about a slanted line. That's long in the future but it will come.
And it's better you understand that you ARE using the Distance formula here.
Yeah I get that
just want to make sure I have this set up right
25x-16x would become 9x
You can simplify things by reducing 25 - 16 to 9.
one last thing if you don't mind, I just want to make sure I plugged in all my numbers right, but I got ~48.056 as a final answer, does that seem right?
Spot on.
thank you sooo much for all of this
Although it's usually preferable to leave it with pi.
Without reducing to decimal unless asked to do so.
cool beans man, thanks again π
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Hey! Itβs not necessarily a mathematical question but i was just curious to know: so basically im taking linear algebra in my next semester of college and i wanted to know in advance what would generally be the main topics that i could possibly learn during the class. My only guess is that weβll learn the matrix thing
this playlist by 3blue1brown is a good overview of the concepts covered: https://www.youtube.com/watch?v=fNk_zzaMoSs&list=PLZHQObOWTQDPD3MizzM2xVFitgF8hE_ab
Beginning the linear algebra series with the basics.
Help fund future projects: https://www.patreon.com/3blue1brown
An equally valuable form of support is to simply share some of the videos.
Home page: https://www.3blue1brown.com/
Correction: 6:52, the screen should show [x1, y1] + [x2, y2] = [x1+x2, y1+y2]
Full series: http://3b1b.co/eola
Fu...
Alright thank you so much ππ
don't worry if you don't understand everything the first time, that's what the class will be for
it's not super difficult, but it is a bit of a different style from the types of classes you've taken before
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This is for the master theorem, what is the "2nd term" they're talking about? Not sure what they mean by terms
Ping me if you reply please, this is for discrete math
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@last slate Has your question been resolved?
Solved...
Lemme repeat the process clearly
Here
@last slate lemme know of any questions
Did you click at it?@last slate
What did it show?
Exactly here it is... you just click and it will download to you@last slate
Is that your pic?
@pearl hull yes it is
@last slate after the v part, we take the v equation and replace the a with a in iii. That gives us the vi down there. And then, you take v and replace it's c with c we made in ii, after which you get vii. From there, you just take the vii and solve it simultaneously with the one from the arrow with terms a and b, and since they have like terms, you get the answers of a and b, and now c becomes easier as you will just take the c we made in ii and replace a and b with values.
Yes@last slate ... so it's well understood now?
We get iv from the second equation in the question. We just make c the subject in that second equation @last slate
We take ii and iv as they have the same terms being a and b on one side, and c on one side. Solving like simultaneous equation while eliminating c now gives us an equation with a and b as the only unknowns which is 1.5a+0.5b=25 which is also same as 3a+b=50
@last slate just to match with the terms there, it's just a zero, so no much significance
Yes, because after that, you just take -25 to the other side and now remove the zero @last slate
Because we just subtracted the two c's on the left hand of both equations so c-c came to 0
Yees @last slate
@last slate from here.... make 1.5a+0.5b=25 and make it to a fraction, and then multiply every term by the lcm which is 2, you get that
Nice @last slate
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can someone tell me what am I doing wrong?
check if u are using degrees or radians
then ill give u a hint
hmm
of course not
that's why I know im doing something wrong
is your work the 2nd pic?
yep
well we know tan=sin/cos
sin and cos are both positive in the first quadrant
55 deg is the first quadrant
so by that logic your work is using radians
you might have meant to use degrees but always have to check the calculator settings
ok lemme try desmos calculator
desmos automatically uses radians unless you specify otherwise
ah yea
I changed it to deg
yep
I was confused for 10 minutes trying to figure it out
dw u havent done enough practice if u havent missed a question because of degrees vs radians
everyone has done it
anyone claiming to not hasnt done enough math
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how can i solve this in a calc?
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What is your question. Explain me
how can i solve the question by using the calculator? for ti 84
Have you tried it in pen and paper
i know how but iβd like to know the calculator method
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how can i solve this using pascels triangle
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Solve using binomial expansion
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the question asks: what is the probability that they need to sample again if 3 of every 5 households in the country have pets?
so what Im thinking, is to use the binomial distribution
where Success= at least 4 households have pets, so the equation I'll use is: 1- h(4;10,0.6) where 4 is the num of successes, and 10 is the sample size, 0.6 is the probability
yea, I think that should be right
more clear when I typed it out, thanks
so bayes theorem would be, prob of F given 0.6 success..
i dont see why you cant just use the formula I typed above?
ok, give me some time to think on it
I think Im getting more confused lmao
I still didnt use bayes..
oh oops btw its b(0;10, 0.6) not h, b for binomial, I dont know why I wrote h
yea I think thats right
Hey i am really sry
because P(X=1)=b(1,10,0.6) and thats for one pet, we get prob of 1- at most 3 pets, which is prob of atleast 4
My phone died
oof nw
whats p and whats q?
p is household doesnt have dogs
n = 10 number of trials
Now you can calc and add for P(x=0,1,2,3)
I am really sorry
I was inspecting the question and it just powered off !
thats me and my phone too lol, always low battery
You have considered having pet as p ?
so 0.6 is the probability of 3 of every 5 households
Yeah its correct then
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the question is is there a partial differentiable funktion g: R^2 -> R with the outcome above
yk what's an easy check we can do
So you are trying find the function?
we found a solution where someone took e^x * sin(y) + c
but shouldnt it be
e^x * cos(y) since when you take the derivitive of x you get cos(y)?
we can compare the partials of xy and yx
Yeah
prob the best way to start off with
You are right
so let's do xy first
Becuase you treat the y-part as a constant
yes
so you take e^x * cos(y)
hold up
what happens to the negative
but cosy derivative is -siny
yes
ah
the way you show this isn't true
is you take the partials xy and yx
they should equal each other
Yep
by Clairaut's theorem
which givves us -e^x * siny + f(x) and e^x * siny + f(y)
wait now im confusedπ
learn Clairaut's theorem
i believe there is some khan academy lesson for this
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hey everyone
When I saw this lemma I immediately thought of what I wrote down. To my surprise the authors chose to do a "more complicated" proof (imo). Is my version wrong ?
your C must be a positive integer, theirs does not
ohh
thats a good point
thank you very much !!
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heya
i have to hold a presentation about "Whole Numbers"
it is also requested that we formulate at least 3 quiz questions
ok... whole number
they should be directed at uni students
(math / education course)
the questions i have right now are:
Which of the following Relations are total Orders on Z? (meaning reflexive, antisymmetrical, transitive and total)
-some options here
Do the whole numbers construct a Field?
-yes / no
but i dont know if these are good questions
i know the subject is weird
the whole course is kinda weird imo
I think it is actually good.
do you have a third question in mind?
some number theory quiz maybe
that is a good one.
yeah that is good
how much time do they have to answer these lol
and maybe formulate that in terms of cardinality instead, so that it's clear and unambiguous
"is 0 a whole number"
they dont have to answer them at all, but i have to create the quiz
it's for uni students
wait what are whole numbers tho
-3,-2,-1,0,1,2,3
integer
ohh
i gotta say tho, the didactics/education courses are all so lame
well, some define that as $\mathbb{Z}$ and some define it as $\mathbb{Z}^{+}$
the math and physics courses are so much better
"whole numbers" usually refers to nonnegative integers
"natural numbers" usually refers to positive integers
huh
we call them "Ganze Zahlen" meaning Whole Numbers and for us that means -3,-2,-1,0,1,2,3
yeah the definitions are a bit.. ambiguous
(though i will admit i've never seen whole numbers include negative integers)
"whole numbers sometimes include zero, and sometimes include negative. But they never include fractional or decimal components"
cool
"mathematicians struggle with naming things"
in german they are luckily not ambiguous, for us, whole numbers always include the negatives
wait what
oh nvm
even natural number sometimes include 0.
yeah
lol
I include zero
i like to call them N_0 then
Yeah, but as CS person, we count from 0, not 1.
different field or different people define that differently.
As a set theory uh.. fan? I like to include 0 too
just, make sure it is clear in your presentation
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the question was get the primitive of f(x) = cos(x) - cos(x)/sin^2(x)
,rccw
good question. No idea

it has nothing to do with it being a constant or smthing right?
bcs I'm still kinda vague on this topic
might also be a book mistake
this is the full answer
oooooooooooooooooooooo
I see it
that's just part of the answer
right
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what should I notice here to prove it?
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the relationship between the functions (x^4 + 1)^(1/4) and (x^4 - 1)^(1/4)
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is the intersection of two planes, a line, exactly one solution?
or is it a set of solutions, as many as the points in the line?
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Do set operations like union and intersection and difference have a priority order? If so what is it
$A \cup B \cap C$
GinNBread
Which part do I do first
the first thing you do is scream at the author for writing that
but after that i would interpret it as A cup (B cap C) and then scream at the author some more
I could use parentheses on first two or last two
yea
Why would you do it on last two?
iβm not answering this question lol just use parentheses
i donβt want to say anything that encourages one operation having precedence over the other
You're confident there's no such thing?
i mean letβs see whatβs on google
I'll stick to parentheses

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You can write is as sin(pi(1-x))/(x-1)*1/(x^2+x+1)
Yes
Monarch of Eternal Night
Monarch of Eternal Night
Then use sin(ax)/ax=1 value as well as binomial theorem in denominator
We can also use a^3-b^3
Or binomial
Both works
That's because to get indeterminate form
Sin(pi.x) when x->0 is 0
But for me they taught the value inside sin should be zero
That's why I took 1+h
Now as h->0, inside also become zero
So now sin (ax)/ax=1
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Prove
$A \cap (A \cup B)' = \phi \$
Where A and B are any two sets
I need to prove this using their definitions
What's their definition?
Like starting with xβ
Is there any further information about A' and B'?
What is the term used to call this method, I'm sorry
x \in
Ah, ' means complement?
What is the correct notation?
Kepe
I have done some working but I don't know if it's right
Can you show that? We might continue from there then
GinNBread
i was very confused because i reacted to a message and then couldn't see it but now i realize the message got deleted
Do you know de morgan's laws?
Kepe
My internet is so slow
My problem is I used the parentheses specifically to reach the answer. My question is how should I appropriately use parentheses
Does that make any sense? 
Are you referring to this step?
Yes
The first line is equivalent to [\text{(x in A) and ((x in A') and (x in B'))}] and when having two and's, you can use the associative property: [\text{((x in A) and (x in A')) and (x in B')}]
Kepe
That's how I would do it
Thought I think it's not wrong as you did it too?
Might wait for what @junior flower has to say (if she is still here?)
Hey
i think u pinged the wrong layla
oh, sry
I have another question
no problem π
Kepe
x not in (A and B)
x in (A and B)'
x in A' or B'
You can also write it like they did it
It's correct. But it doesn't cover the universal set
The middle will still be missing
You can try drawing it
It will look like this
Now if you read this again,
you also have the requirement "x in A u B"
So the entire area around the two circles falls away
What does \ mean
"without"
oh -
Yes
So yeah, you did everything correctly but went wrong in saying
Because it covers the universal set in Venn diagram
So the definition given in text is wrong
No it's correct too
Ah, that part. Yeah, it should say {x in A u B | x not in A n B}
You want to represent the shaded part of Figure 1.11
Yes
Like this, everything around the shaded part is included too (except A n B)
I just wanted to find a simple way to represent it, sorry
Thank you for your time
.close
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Use .reopen if this was a mistake.
Btw, it's generally a bad idea to define a set using {x | ...} without specifying what x is in. Look up Russel's paradox (or Barber's paradox).
You only do that in non-rigorous settings where the reader is assumed to know what x is in
Hey
Is there a good resource to learn sets
My guide is not cutting it
I have been most things outside and from this server. God bless you all
Though not sure if he has much on proofs
I'll still spend some time on it the unit tests help
Depending on your class the proof exercises are also really important
So yeah, just google "set proofs" and I'm sure you'll find something
I've been struggling with proofs
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Hello! I'm trying to study some statistics in my free time and I have a question about multinational coefficients. My book explains binomial coefficients (regular combinations) as an attempt to perform an experiment $k$ without replacement, and I get that analogy; however, when it comes to a multinomial coefficient, I struggle to use the same analogy, as for some reason with multinomial coefficient, unlike with the binomial, we start to account for the items that are left out (unchosen), and I cannot understand why, since the derivation of the multinomial coefficient from the binomial coefficient (which I have attached) seems to omit the unchosen items.
RIGIK93
from those which are left out at first you want to choose in the next go
@quiet spire Has your question been resolved?
? I'm sorry, but I don't fully understand
I understand that part, however, what I do not understand is why we are choosing from those unchosen too (conceptually)
In a regular binomial coefficient, it is (n-1)(n-2)(n-3)/3!, so we don't really care about the "unchosen" items; however, with the multinomial coefficient it does not seem to be the case
So this is why I'd like to find an appealing analogy
that formula is the same as n!/(3!(n-3)!)
so the unchosen items also "appear" in the formula
well ok not the same cause your formula is wrong, but this would be the correct one
intuitively, not choosing items is the same as saying: I pick those elements as those I dont want to choose. so you "chose" them as your unchosen items
that sounds weird but hopefully makes sense after reading it a couple of times
Yeah, sorry the corrected formula would be:
$$
n(n-1)(n-2)/3!
$$
RIGIK93
How I view this is:
We have n choices when we are picking the first object, then n-1 for the second, then n-3 for the third, and we also divide by the number of possible arrangements. I don't understand where in this reasoning unaccounted items are included.
lets say we have 10 objects. and we want to pick 3 of them
then we could say, ok 10 for the first, 9 for the second, ..
like you said
or we could say, I instead pick 7 objects and afterwards choose the leftover 3 items as the actual 3 items I wanted to choose
which would be n(n-1)(n-2)...(n-6)/7!
to get from this formula to the one I wrote, multiply by (n-3)! on top and bottom
$\frac{n(n-1)(n-2)}{3!}\cdot\frac{(n-3)!}{(n-3)!} = \frac{n(n-1)(n-2)(n-3)!}{3!(n-3)!} = \frac{n!}{3!(n-3)!}$
Denascite
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guys am i allowed to ask z-transform question here yes or no?
dont ask to ask
i dont wnat to get banned
worst that can happen is someone not available who knows how to answer
if it's nota llowed
You will not get banned by asking to ask
why would you get banned for that lol
!da2a
No need to ask βCan I askβ¦?β or βDoes anyone know aboutβ¦?ββitβs faster for everyone if you just ask your question! See https://dontasktoask.com/
@bright grail just post the question
what would the process look like if i inverse transform this
this is my question pls dont ban me if not allowed
Relax
Nothing of the sort
@bright grail Has your question been resolved?
What exactly do you mean by transforming?
I do it via tableβ¦
There is a definition but itβs a yucky surface integral idk your purpose for this if itβs just to learn the math you can do it by definition if itβs for signal processing β¦ just use a table bro
@bright grail
i am bro
but i need to ask something
when you do partial fractions
are you expressing the denominators with complex roots as 2 binomials multiplied or only 1 quadratic
that's where im stuck right now
solving for the coefficients
or you use cover up method?
Well honestly the goal is to get into a form that matches the tableβ¦ you can split up partial fractions into fractions of any residues that are multiplicative elements of the the polynomial in the denominatorβ¦ Iβd suggest going down to binomials if convenient as there are pretty convient rules in that table for them
If you need a review of partial fractions (as in you donβt remember how to do it β¦ itβs probably quickest to watch a video example)
i know how to do it
but not using cover up method
for z transforms i noticed almost all the time people use cover up method
why is that so?
Use whatever method you want man β¦ dont worry about what other people do so much if it works it works
If you can get a right answer you can. Get a right answer
This is the method they use itβs quick so I get the utility
yeah that
ok man i will use that starting now
thanks
i am used to just making a system of equations and get all the coefficients
can i ask what u are searching to get acces to this
what keywords
Idk I probably searched βHeaviside cover up method for partial fraction decomposition β or something like that
Knowing the full name of the method and what itβs used for is generally enough for a good google search
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Why and how can we do this?
Because we are changing the elements so the matrix won't remain the same only right so how determinant would be same?
it's one of the properties of determinants
when you add rows together the determinant doesn't change
But here we didn't add rows no?
we added row 2 and row 3 to row 1
We added elements of same row you mean?
Here we SUBTRACTED the same column elements
Still the determinant won't change?
@subtle blaze
correct
Can I multiply 2 columns tho?
they are doing row operations. but no, you cannot
Oh damn, thanks man
Btw is there any proof available that if I add or subtract 2 columns in a matrix
Determinant don't change
Because it's hard for me to digest something as it is unless proof isn't given
I am not asking to prove this
Just asking, is there any proof available
If yes, then I'll try myself for fun
I'm sure there are proofs of that, yes
Thankx π₯³π₯³π₯³π₯³π₯³π₯³π₯³
Gracias
yw
@tiny drum last help
Can u share a site or pdf or can u name anything where I can get ALL properties of matrices and determinants?
sorry, no. try asking in #linear-algebra
Real, thanks man!
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The , means?
a comma is used to separate every 3 digits before a decimal point
And is called?
it doesn't have as much of a common name (unlike the decimal point it doesn't change the meaning of a number), although it acts as a "thousands separator"
some styles prefer to use spaces rather than commas or just leave it out entirely
k.
@marble plinth Has your question been resolved?
whats not answered?
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help
"it" referring to? everything, or a particular part?
like i know suvat
and that
but when you use s = vt -0.5at^2
my brain dies on choosing acceleration
bc in one part the acceleration is g and the other is -g
in question 1 part a
Cool cool 
my exam is this month and i do fm im prolly cooked
You could, e.g. find the "additional" height the ball rises to before it starts to drop again, then use this to find the velocity on hitting the ground, for example
Awwww, did you have the maths one today? 
nah im year 12 right
icl im confident on everything bar these little aspects of suvat
pure carries me
Oh 
i see that makes sense
but im wondering right
the mark scheme did it in one equation
this
How did they do it?
ill show you
lie they chose g
and my brain dies there
right because they set downwards as positive
bc overall displacement is postiive according to them
so we know that
meaning they saying acc
wait
acceleration is always down
wtf
then how come im using negative g before when it goes up and its right
Hmm, those arrows
what on earth-
bro how has mechanics got me high
Nah, mechanics is generally pain tbh, unless you get someone who's really good at teaching it 
because my initial instict is in the first section
got you bro
first instict* is because the ball is rising
it goes against g
so is decelerating
so in that part g is negative
then after reaching its maxmima
accelerates with g
so its now postive
also seems like they're choosing a = -g here, or expecting you to use that(?)
yeah aswell
Which makes sense, as you're shot up, gravity is acting downwards throughout
mabye because they took gravity downwards as negative
yeah like displacement
mabye im overthinking it
Actually wait no they didn't 
Yeaaaa I really don't know about these 
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can someone help me please
@short cove Has your question been resolved?
please help me
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I have to use partial fractions to evaluate this fraction. When we divide the nominator by the denominator we get f(x) = (2x^3 - 4x^2 -x - 3)/x^2 -2x -3 = 2x(x^2-2x-3) + 5x - 3.
My question is why do we rewrite is as 2x + (5x-3)/x^2-2x-3
And not 2x(x^2-2x-3) + 5x - 3
This is what the numerator is equal to, so when you replace and split up, itβ¦
β¦turns the fraction into this expression
You mean we get 2x(x^2-2x-3) + 5x - 3 from dividing the numerator by the denominator, and we can divide this expression by x^2 - 2x - 3 to get the fraction?
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i need help in this problem
@rapid cairn Has your question been resolved?
<@&286206848099549185>
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Hey guys
I get the stuff in green but then the red stuff happens and idk what it means π
Like if I was given a problem like that I wouldnβt be able to do the red stuff ykwim
So can someone explain what it is
Tbh it should specify that B is mid point
Oh ok
Basically, B is mid point and distance of AB = BC
AC = AB + BC
= 2(AB)
Can I say AC = 2(BC) instead of AB
Does it matter?
Ofcourse
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Hey how do I prove that this thing is a trapezoid (using vectors)
I drew a really vague sketch and also proved that diagonals are perpendicular
Then I also tried doing something something equals 180Β° but it didn't turn out right
In LaTeX, please?
What?
Don't mind the language only the coordinates are important
There will be only 3 vectors
Wait, why did you prove that the diagonals are perpendicular?
huh
Like every other vector formed by lines will be collinear to these three
there was another question asking me to do that lol
wait wdym three π its a trapezoid isnt there supposed to be 4
oh
Ohh sorry mb lol
I read it as parallopiped
Sorry
ohhh
okok
i searched up that a pair of adjacent angles must be equal to 180 degrees and that would make it a trapezoid
2 vectors collinear and one side perpendicular to both of them
but when i tried doing it that way it didnt rlly end up being 180
why perpendicular?
Not perpendicular sorry lol
huh im confused π
Damn sorry i read it as right trapezoid
Only two sides need to be parallel any two and other two should not be parallel
hah i think its time to rest π
would this prove?
cuz like what if its another shape
or is only trapezoid like that
Trapezoid is defined like that
It has two parallel sides and two non parallel sides
how do i prove that they're parallel
Ya i only slept 4 hrs in 2days π’
Wait
U need to
Find vectors of side
ah what
Subtract v1 with v4
And v2 worh v3
See v1-v4 and v3-v2 are scalar multiple of each other
Did u get it ??
wait
what did you do with them
howd they turn into that
shouldnt it be 2i+4j?
whys it 10
oh wait
