#help-10
1 messages · Page 415 of 1
right it's +0z. so it doesn't matter what z is, that's why you need the second variable
[(i+4)j -2i, j, 0]
nono, it's [f(j), j, k]
for whatever f is. haven't worked it yet
the point is z can be anything and it still solves the equation
okay S2 looks good
guh y for S1 is gross
intersection is the easy part. at least for these ones; you chose good variables
so ig it would be the element are the same
right
so k
(if we were being careful we really should have used a third variable l for S2. but then we'd get k=l from the z-coordinate, so it's fine)
ig i made z = k for both
but since they are separate equations ig it would make sense
so S1 intersect S2 = {k}
y'all good
1x3
yes, i guess, but you already did that
But yeah, if $( -3i + (i-1)k , i - 1 + k, k) = (-2i + (i+4)j, j, k)$ then $j=i-1+k$ from the y-coordinate, and now we have to check if the x-coordinates match.
ENStucky
right
oh substitute that in ok
right
and the z-coordinate, well we didn't use it because of that "third variable" thing I talked about above. here it just tells us k=k
so the only information left is in the x
so i got -3i + ki - k = i -5 +ki +4k
hell nah
but let's think for a second about what we got here
...no
j /
you just showed that k is not a variable in S1 intersect S2, but has a specific value
and j is written in terms of k, so that's also not a variable
conclusion: there's no variables here. so only one point in the intersection
noooooooooo
gotta find that point
so then i get a single solution ?
right
gg
gg indeed!
is k correct doh
yes
nice
wait just check my sol
so S1 = (-2i +3/5, i/5, 1-4i/5)
S1 = (-1/5 -6i/5, i/5, 1-4i/5) S2 = (24/5-21i/5, i/5, 1-4i/5)
@vapid tiger Has your question been resolved?
hi
How you know you a helper?
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Can someone please draw the free body forces diagram FOR THE SYSTEM for this question?
I understand there has to be a tension force upwards in the string but then i don’t know which force will balance the horizontal component of the tension?
@sullen prawn Has your question been resolved?
@sullen prawn Has your question been resolved?
@sullen prawn Has your question been resolved?
What chapter is this from
If it's NLM then I can help
If it's rotation then I can't 
@sullen prawn
Yes it is
Okk
Nah this aint rotational motion
I just need the freebody forces diagram
Actually i figured out that the reaction force must be at A
If we take it to be our system both rods
Wait lemme just show u and u tell me if its right
Im talking moments abt A so no need?
No
I mean i will give jee and i’ll prep for it but only in the last 2 months, im not prepping for it seriously
This is for further mechanics in further maths a-level
@frigid burrow some other dude gave this
Said no reaction force at A
There should be
As "A is attached to a smooth fixed pivot"
So there would be some force exerted by the pivot
A special case might be that it is zero
But we should always assume it
Oh can you tell me more?
Further maths is an A-level subject offered by cambridge assessment international education, further mechanics is one of 4 components offered(other beings further pure 1, further pure 2 and further stats) for further maths
Ohh
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Hope is that
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Im getting a complex number
why would you block me...

@split sailDon't troll.
.close
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Is there any systemized way of multiplying 2 digit by 2 digit numbers in your head?
Few ways, you can memorise a times table or just memorise a method to multiply numbers
You just need a good brain. Try like.
Do you know how to multiply numbers without a calculator?
Odd number and even number.
Well ofc
I just need to find a more of an efficient way to do it
if you can multiply a 1 digit number by a 2 digit number, then you can multiply by the 1s place, then multiply by the 10s place and multiply by 10, then add together
Wait you mean like 1s places then the 10s and multiply both results by 10 and theb add together?
Then*
It's just easier to do it in my head most of the time I just need more speed+slightly more accuracy
I'm like at a 75% accuracy but I need more speed
what is this for?
For my own personal development
In math
The more u can do in ur head in an exam the easier
You can break numbers down into simpler ones. Multiplying 27 and 25 is also 3 by 9 by 5 by 5
e.g 24 * 32 = (4 * 32) + (2 * 32) * 10
Multiply in the order that you can do the quickest
So you would only multiply by 10 the 2•32? Following that notation ofc
I'll try both
yes, because 2 is in the 10s place it's really 20*32
Does this work for every single one?
distributive property
that’s all it is
I'll try it thanks bro
Where chu pull that 2nd 32 tho
24 = 20 + 4 so 24 * 32 = (20+4) * 32 = 20 * 32 + 4 * 32
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need my answer checked on this.. im pretty sure its wrong tho
can you rotate your laptop
its 360 ig
Think its 180
😭 ??
Isnt 360 a full circle
nvm not 360
how far do you have to turn your laptop to get one triangle to the other
i was thinking smth else
wouldnt it be 180
I think so
its 180 yeah
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ok... I AM BACK
find the slope -> plug slope & the two points on graph into point slope form -> simplify into slope intercept
okay ty bro
i found the slope
with m = y2 - y1 / x2 - x1
so what was your slope you found
2
this is for problem 24 correct?
use this formula to plug in
idk what thats called but yes ik what that is
y - (-1) = 2(x - (-2))
is this correct?
yep, now simplify
y + 1 = 2x + 2
y = 2x + 1
y - 2x = 1
i think
idk
we only just now started learning this formula, two weeks later
but im trying to do late work and i was missing this page
gimme a sec
okay, this becomes y + 1 = 2(x+2)
make sure you not only multiply the x by 2 but also the 2 in the parenthesis
OH NO
im sorry i forgot that
y + 1 = 2x + 4
y = 2x - 3
y - 2x = -3
isnt this it?
a + b = c or something
y should be on one side
y = 2x - 3
can we multiply everything by 2 or something
or -3
i think thats a possibility
idk
y + 1 = 2x + 4 to y = 2x - 3 is wrong by the way
idk what to do
what
waht the
bro im tired sorry
y + 1 = 2x + 4
y = 2x + 3
y - 2x = 3
is that it?
y = 2x + 3
is what you're looking for
oh
this is the wrong equation
just use yeah
y = mx + b
why didnt we do that
you needed to go from this equation to the one i just posted
or wait
no actually you could
its all good
you can get the slope and just look at the graph for the y intercept
yep
alr ty
you know how to check your answers right?
not really
the slope is visible without doing the y2-y1 equation
if your teacher hasn't taught this, then maybe wait to advance to this step
thats just how i normally get the slope
i just learned that there were two ways
this one was faster so i usually use this one lol
ty though
i have another paper
this one idk how to do
i can try to explain it for you
2 = |x| - 1
it says solve each absolute value equation
14 = |x| + 2
|-2x + 8| = 20
2|x + 8| = 20
2 <= |x| -8
|x| + 5 >= 10
|2x + 5| >= 9
-2|x + 4| <= -6
ok for this one, make |x| on one side alone, and then
x = 3 or x = -3
so
2 = |x| -1
3 = |x|
x = 3 or x = -3
?
yes as |x| = 3 --> x = +/- 3 (plus or minus 3)
okay, thank you'
ive got to go now, good luck!!
do .close
tysm
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ABCD is a quadilateral, O is the intersection of AC and BD, AB=OD, AD=OC, BAC=BDA, what type of quadilateral is ABCD
i tried drawing and i have no idea
I think ABC and ODA are similar triangles
but idk what that means
for the quadrilateral
how do you prove that?
SAS
wait nvm
wait SAS?
AB=OD BAC=ODA where is the lasr side
also isnt simmilarity only like AA and SAS is for congruency or am i stupid
@gloomy vector Has your question been resolved?
AOD+COD=180
AOD+OAD+ODA=180
BAO=BAD=BDA=ODA
AOD+COD=AOD+OAD+BAO
COD=OAD+BAO
COD=BAD
you get your SAS
@gloomy vector Has your question been resolved?
isnt AOD=COD?
also how is BAO=BAD
i meant BAC
how about this
nowhere does it say that
From this congruency, can you say something about AB and DC?
(they arent equal, but there is some relation between them)
err like BD=CD so CD is related to AB?
Think of angles attached to the sides, and what conclusion you can make from that
wdym
@gloomy vector Has your question been resolved?
well... ABD and BDC are equal
wait whar
|| AB and CD are parallel making this figure, at least a trapezoid|| idk how else to explain it so read at own risk
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How would one come up with the N = 2Max{N1, N2}? Like where does it come from? Ik where N1 and N2 came from: they're subsequences of N, but where does 2max come from? Why would we wanna take the max of both subsequences and double it when proving Zn converges to the same limit ?
Sorry if it seems like it should be a straightforward answer, just trying to understand how they got the answer :) Ik I could prob just say "Oh its true by Bolzano-Weierstrass Theorem" but i wanna know how the answer above came to be ! (esp since at this point of the textbook, B-W hasnt been introduced yet)\
A lot of yapping mb LMAO
you have an N_1 and N_2 to play with. taking the max couldn’t hurt
because we want both the x_k and y_k sequences to be close enough, so we take the max
and double it because we have to account for the values of the other sequence
why is our statement true? well it's because intuitively, x_n and y_n both get really really close to x
so imagine such a sequence in ur head
like if x_50 and y_100 onwards are close enough, then we can't guarntee z_k is close enough until z_200 onwards
becaus z_199 = y_99
you wanna pick a point N where eventually 'x_n is close enough to x' and 'y_n is close enough to x'
maybe x_n gets there faster than y_n so we'd need to take the max
wait
i think i misunderstood the max function then
does the max function take whichever sequence is bigger, as in like
takes the sequence that uses elements higher above N if that makes sense ?
max {N_1, N_2} is the bigger of the two values N_1 and N_2
if N_1 = 4 and N_2 = 6 then max { N_1, N_2 } = 6
wait im dumb N1 is in the set of Natural Numbers
ok i get it now
ill close this ina bit lemme just reread over what everyone said to make sure i get it
.close
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Someone please refer me a video from where I can learn this … it’s part of theoretical distribution basics… no advance stuff plz..
@crude skiff Has your question been resolved?
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What is 3/4 in decimals?
Pls show me the process
answer him first
try convert the number into a improper fraction
converted
what have you got
135/4
actually have you done this
yes
ok
got this
what to do next?
<@&286206848099549185>
hey?
it's easy i know but i need to convert in decimal
so if i cross out 100 then how will i be able to convert into decimal
what
oh
A mixed number is a whole number plus a fraction. If you convert the fraction to a decimal value, you can just add it to the whole number.
multiply top by 25
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Studying for a math exam. This is a practice problem. Question b and c I am stuck on.
Here is the thing
According to my peers, the professor said that there is no analytical solution, despite what the problem states. his answer he wants is: "use math cad and use a Give and Find algorithm" I don't understand why we can't treat the constant as a vector
Apparently there's no analytical solution because matrices.
Same confusion for c. Apparently it's non linear now. My classmates aren't explaining in a way I understand, so I was hoping I could get some insight here.
It's especially frustrating that the problem says "analytical solution", yet apparently there isn't one so it's a trick question. I'm wondering if the student misunderstood.
Thank you
Also, I showed my work for b). I only did quadratic formula, but to finish the problem, I would just treat the exponential part as a scalar, only constants are vectors. That shouldn't be an issue, right?
I don't understand why we can't treat the constant as a vector
you mean the A and B right ?
@gritty oracle
I mean like what I wrote in my work, provided below..I'm not sure if A and B are vectors
It doesn't say if A and B are vectors. I'm assuming they're scalar
Cuz that'd be vector * vector and we aren't using dot products / cross products / geometric products in this class.
yeah if A and B are scalars it's completely fine, it's like solving 3 scalar ODEs at a time
Same for c?
Sorry finish what you were saying
but yeah you have 2 linear independent solutions c1 exp(s1 x) and c2 exp(s2 x), which means the general solution to this ODE is c1 exp(s1 x) + c2 exp(s2 x)
where s1 and s2 are your two roots
it's a second order ode still
I'd expect you to find c1 and c2 in terms of y(0) and y'(0) also
(or at least write the equations they must satisfy)
This is exactly what I thought! I am frustrated that my classmates are saying I am wrong. I also used chat gpt (albeit, not always accurate) and it gave the same solution I thought
The reason why people are saying it's not analytical os because one student talked to the professor apparently and told everyone that's the answer but I am wondering if he misunderstood
We did this in class :/
Are you sure by the way? Is there any way you can prove it
Like, I don't want to suffer from conformation bias here
well if A and B were matrices they're prolly right
even 1st order ODEs y' = Ay where A is a matrix are already a decent pain in the ass to solve in generality
if A and B are scalars, it's just 3 1D equations in a trenchcoat, if you want to be sure just work with the 3 equations instead
Yeah I agree. But the problem does state anything about A and B so it's an unfair problems
Does the same hold for c?
Sorry if you said already
I didn't say but same thing yes
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Hello I tried several times to solve a question, but I couldn't. So I checked the answer, but I wanted to know the teacher's answer is only answer
what's the question?
what's the question?
ah
this is not in my course
well, seems like you gotta mention helpers
i can't help you with this
Ok thank you!
now someone will help
!15m
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Oh
It's helpful to write out the definitions of du/dx and dv/dx
ok
by mentioning
ok so what are you stuck at?
My teacher said "you have to explain why the approximation becomes an equality"
And I couldn't find answer
So I found a picture that includes the teacher's answer but i wanted to use that kind of way
This is the teacher's answer
<@&286206848099549185>
yep this checks out
So is that the only way to solve the question?
no
if its only limits and their properties then this is the only way
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Hello everyone
hi what's your question?
Isnt the answer he supposed to be C? Why is the answer A then?
first graph y = f(-x+4)
if you have a function f(x)
graphing f(-x) would mirror that function around the y-axis
ik
and i did it
but
isnt f(x + 4) a 4 units shift to the left?
why wsa the answer A then? it was supposed to be C
also
i got this from a government website
so te asnwers arent wrong
or so i think
its a provincial test
im all ears
I think the shifting is done first then the reflection
it would be -8 so reflected becomes 8
yep when rotating around y-axis
all x becomes -x
ah i see
so my mistake was
relfecting before shifting? so shifting before reflecting
is there like a rule for that?
i need to remember it
I can’t word it tho
mm
but it seems plausible
ok
thanks man
i was stuck on this for a while
ah yes
it seems there was indeed a rule
thank you
have a good day
evening
orrrr
night
or afternoon
or midnight
yeah
have a good day, evening, night, afternoon and midnight
and dawn
.close
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so my limited brain capacity tells me i just have to find original function
which i think is
$-x^{2n} \le \frac{1}{1+x^{2}} - \sum_{k=0}^{n-1}(-1)^{k}x^{2k} \le x^{2n}$
am i right in thinking that i just have to show this inequality holds true on interval x:[0,1] or is that insufficient
Dootud
@light flume Has your question been resolved?
<@&286206848099549185>
yeah?
What do u need
That’s an alternating series, use Taylor series expansion for arctan
taylor series isn't taught in highschool here
i cant use
Ur in HS?
im just wondering if my inequality is correct
yes
AP calc?
i dont take US curriculum so idk how ap calc works
Canadian curriculum?
australia
Right I see
This is right
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I dont understand how we got this. Could someone explain?
Is it some formula in use or?
,tex .exp rules
riemann
looks super wrong
so you do 4/3 − (−2/3), that's 6/3, so a² is right
but then −3/2 − 1/2 is −2
@mighty agate Has your question been resolved?
idk
Why are we subtracting tho?
when we multiply we add the powers
Ohhh yeah
this is division
oh right yeah the second one is wrong it looks like I looked at the wrong task that's why
Thanks for pointing it out
.close
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If the universe of discourse is the integers, determine the truth value the following statement
∃m∀n(m - n = 2)
Can someone please help me figure this out
the ordering of quantifiers is important
correct
There exists a real number m, such that for all real numbers of n, m -n =2
but my confusion lies in lets say we replace n with any real number right example -4
m + 4 = 2
m could be some number of -2, right so that would be true no?
lets say we replace n with any real number right example -4
that's already contradicting what the statement $\forall n$ means
riemann
Hello
!occupied
Someone else is already using this help channel. If you need help with a question, please open your own help channel/thread (see #❓how-to-get-help for instructions).
in what way?
-4 is an integer
ohhhh
so when fixed it must not be contridictory
m as a fixed number must make the statement true for all real numbers
@tardy epoch
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Could someone please help me with this?
Which part
Mostly the arcs
Hint: Consider the arc MNP, what's its measure?
i mean the arc starting at M, going through N and ending at P
idk the right notation
If it was arc MNP, it hold be 62 + arc MN, but I don’t know how to find MN
I'd actually find arc MN through arc MNP
How?
does that configuration look familiar?
green is what you need to find
orange is 80
Exactly
and now you can subtract 62
to get MN
and MQP is easy to find
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Just need help factoring m² + m - 90
There's no gcf and idk how I could do difference of two perfect squares with this
Oh thx
Immm not seeing anything that could help with this tbh. Maybe I'm not looking in the right spot
The section "a method for simple cases" is where you should start
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So I have this problem and just wanna be sure. If lambda(A)<infinity, then 1_A is measurable and it is a positive function so 1_A is in M^+(B(R)) which also means 1_A is in L^1(lambda) right? but how do I get the scalar a into this
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Algebra question: how do I make this a compound inequality?
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Hello
Not sure where to start
and ivt
How do I apply those
nvm i don't think mvt works
Yeah thats ivt
(not told that f is differentiable anywhere)
You may wanna consider the function g(x) = f(x) - x: this is continuous (why?), and so you can apply IVT to that instead
As the range of f is [a, b], f takes on the values a and b - what does that mean?
@harsh remnant Has your question been resolved?
f(a) = a?
Not necessarily at x = a, but there's some p between a and b such that f(p) = a
@unreal musk (by the way, I'm doing the problem too, as an exercise) I noted that g(a)= f(a)-a ≥ 0 and g(b)=f(b)-b ≤ 0. Then of course there exists x' such that g(x')=0. How can I formalize that last part?
Be careful, it isn't necessarily the case that g(a) is nonnegative and g(b) is nonpositive
But, as before, g is continuous, and (upon a correction) either one of those are zero (in which case, you're done) or one's strictly positive and the other is strictly negative (in which case, what does the IVT tell you?)
but since range(f)=[a,b] how come g(a) = f(a) - a is not necessarily nonnegative?
Because while the range of f is [a, b], you do not necessarily have f(a) = a nor f(b) = b (nor swapping them around neither, you don't have to have f(a) = b and f(b) = a)
What you \emph{do} know is that there are some $p, q \in [a, b]$ such that $f(p) = a$ and $f(q) = b$.
Using the fact that $p, q \in [a, b]$, what can you say about $g(p)$ and $g(q)$?
@unreal musk
that $g(p) = f(p) - p \in [0, b-a]$ ?
Ze_Beeg_Almond
Well, g(p) >= 0, which you have 
is it that?
Cause a <= p, that makes f(p) - p = a - p >= 0
(but that's the statement we needed, for which you can replace in here
)
Similarly g(q) can be considered and all...
yes, $g(q) = f(q) - q \in [a-b, 0]$ ?
Ze_Beeg_Almond
Yep, g(q) is nonpositive 
Then, of course 
but i still don,t understand why my previous thing didn't work
at $x = a we have g(x) = f(x) - x = g(a) = f(a) - a and then, since f(x) \in [a, b], we have g(a) \in [0, b-a], no?$
Ze_Beeg_Almond
Actually yea it's alright, coming to think about it
okok
f(a) is at least a
yes
Gotcha 
so the function, evaluated at the leftmost point in the interval, is nonnegative, and for the rightmost point, it's positive, but returning to my previous commment, how can i formally justify that there exists x' in [a,b] such that g(x')=0. do i use continuity or what?
Continuity and IVT
g(a) = f(a) - a is nonnegative (as above, f(a) is at least a), and g(b) = f(b) - b is nonpositive (as f(b) is at most b)
Either one of g(a) or g(b) is zero, in which case, whichever of those, you're done
Yes
Otherwise g(a) is strictly positive, and g(b) is strictly negative, and of course 0 is between those, and it should be clear that g is continuous, so the IVT tells you...?
that there exists $x' \in [a,b] s.t. g(x') = 0 <=> f(x') = x'$
Ze_Beeg_Almond
There you go 
$\iff$ and $\exists$
@unreal musk
and for all?
$\forall$
@unreal musk
alright man thanks
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Why are we allowed to say that final velocity is proportional to square root of displacement? Where did acceleration go?
the formula only works if acceleration is constant
$v_f =\sqrt{2a \Delta x}=\sqrt{2a} \sqrt{\Delta x}$ and $\sqrt{2a}$ is a constant
Civil Service Pigeon
also why is it c?
you can just use this tbh
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Hello, I will first give conext to the problem and myself. I am a highschool student who has taken little calc working on rockety. Inside a rockey to find how much fuel is burned you must know the surface area of the fuel grain, which is where my issue arrises.
finding the inner surface area of a shape like this is easy, it would be the permiter of the of the "top hole" * length
i cannot understand how to find the surfave area when it is rotated around a helix like this
Logic would tell me that it should be the same bc the permeter of the face is the same, but alas the surface area is differnet
apparent this is due to streching of the lateral face, which made some sense to me after I took a cylnder toy and twisted the top and bottom
the volume and surface is the same for the same object in real life, but the height goes down, but in my instance in my fuel the height stays the same therefore the surface area must be greater
Now i though I was just turning my shape, not twisting it, but appertly it must be twised bc with not other changes other than just twisting the surface area increases
so how can I calculate or esmiate this new surface area???
I found a website that seems to be dealing with a simialr problem, but I dont qoute understand their soultion
I would need to also somehow be able to iteratlivly calculate this in exel
Thank you!
Take a single slice. Has the shape inherently changed?
Exactly.
ok... why does my surface area change in that case?
It shouldn't.
logic would agree, but it does
same volume different surface area
5% difference which can matter in rockets
supposeably this is the soultion, but these means nothing to me, I dont know how to use this
damn that's pretty interesting
I have an idea of why
imagine you have a square
intially
ok
if you push the bottom side to the right
if would become a rhombus
but then
the vertical height would lower
as a result
do you get what I'm trying to say
one sec let me draw
What you are interested in is Cavalieri's Principle.
this what im trying to say
so originally when you have the cylinder, your surface area is formed by long vertical rectangles
but when you curve them
you lose some of the height because of the distance which you've slanted them
because the height of the cylinder obviously don't change, you gotta add extra surface area
it would have a different area no? isnt parrallegram area base*height.
to maintain the height
oh wait yeah
oh but still
that proves my point
cause then
you have to stretch the rhombus
vertically
well yes, but my 2 shapes have the same area
The area of the rhombus remains the same no matter how far you stretch it.
imagine looking at it like this
ok
like don't look from the top side, look at it from the side
cause when you twist it, from the top down, if you kept making cross sections, it would look the exact same as the original
but if you twist it
the intial long vertical rectangles
are twisted
this 💀
I don't think there is a simple formula
cause it also depends
on how many turns your helix has
the more turns, the more surface area
probably from 0.75 to 2
you'd have to use calculus to calculate the curved surface area
the most ive taken is calc bc this is with no help beyond my understanding
which is why im here lol
Calc BC doesn't usually cover this type of calculus.
yes
cause you've already found the SA with your software
hence why im lost
Calc AB and BC covers the same topics in Business Calculus in college.
But not what you would find in engineering.
its to calculate mass flow rate of fuel, ik how deep it burns, i just need the surface area
I think you could approximate it
i am making a engine model
using what I just did
just calculate
how much
the perimeter to area ratio changes
when you go from a square to a parallelogram (with a base of 1m^2)
yk i still dont qoute understant how you are streching it
like you know how when I nudged the base of the square, I had to add extra height
wait can u call 💀💀
sounds ridiculous but I can explain
better w vc
sure
It would stretch it now that I think about it. Imagine two points on an untwisted cylinder. If you twist it some amount dx, it from a triangle whose hypotenuse would net be the same length as the untwisted length.
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false
Sorry, im new to proofs, but if its asking to determine if this is true, and to prove my answer
yeah, its obviously false
but would there be any further proof to show that
can't think of anything
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Can someone double check that this is the correct usage of permutations and n choose k
for option (a) if its an ordered sample then just picking 2E A N is not enough u have to permute those 4 letters too
(b) looks good
Should it be 5P2 * 4P1 * 3P1 in numerator?
ummm not exactly because ur just permuting two same alphabets
it doesnt make sense
what u shud do is u shud think like
ah okay now i have picked 4 alphabets
in how many ways i can permute them
AKA how many words i can make with them
because technically each word is an order of alphabets right
if u find number of words u can take it as number of orders u have picked out the alphabets
Hmm I'm still have trouble understanding, my logic was that the first 2 tiles drawn have to be E, so therefore out of 5 E's we are taking 2, and not replacing them, so its 5P2,
u are correct
i am saying here u cant do 5P2
because the objects arent distinct
u cant differenciate between two Es so why use nPk
instead just ue
nCk
but then after choosing all Es A and N u have to permute them as a whole
Interesting
because the order in which u pick
Es As and Ns are different
like u can pick two es one a and one n
OR u can also one pick 1E 1a 1n and then finally 1e
u see they re diff events because the order is different
have u learnt finding number of words from a given number of letters?
Let me think about that, could you be more specific?
like suppose
i gave u 2As one B one C
how many distinct words can u make out of them
using all of them
i forgot to mention
Wont it just be like 4 * 3 * 2 * 1
yep that is correct but here i have given u duplicate letters too
if u consider both As as distint ull get extra cases
ABCA is the same word even if the As places interchange
So the probability of getting ABCA at random is 2/(4 * 3 * 2 * 1) ?
no not exactly
i think i am confusing u
like in this case that is correct
but not always
there is a way to find number of words without the 4* 3 * 2*1 method using nCp too
i am sorry if im wasting ur time XD im not very good at explaining
No worries
I appreicate your help
Perhaps you could explain this once more?
okay sure
so see
they said
we have to picked as an ordered sample
which means
the order in which we pick the letters
will matter
Yes
so like u can take in the order A N E E or A E N E
Yes
both will be different events right
Yes
because the order of letters change
Let me propose a revised answer one second
Skidibi toilet
Thoughts on this>
?
14 tiles total, no replacing, and we are selecting E,E,A,N
Where there are 5 E tiles, 4 A tiles, 3 N tiles, at the start
and 2 B tiles
yeah see the problem is