#help-23
1 messages · Page 313 of 1
yeah
took me like three tries to get the right answer for each qs
all good
done?
yup!
ok welcome bye
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hello , can someone help me with question
Hint: ||Expand (A + 4I)(A - 5I)||
you mean A + 2I ?
No, but you will need to expand the (A+2I)(A-3I) as well, yeah
i did but I didnt know what to do next
Expanding (A+2I)(A-3I) in the given equation will tell you what A^2 - A is. The latter term also appears when you expand (A+4I)(A-5I)
@restive lance Has your question been resolved?
Im trying to know what to do next
The rest is basically algebra, multiplying by inverses, using the A^2 - A equation wherever you see an A^2 etc
There's a lot of ways to do it
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for 15b what do these mysterious symbols mean
but I go to trinity
we use WAEP
there’s no point of me doing pmod
you're stuck on part b right?
try translating that statement into words
yea
for all integers x there belongs an integer
to answer your question....
Bracket 1: all values x are integers
Bracket 2: there exists a value y in the set of integers
Bracket 3: then just 2xy=24
and it mentions counterexample so you just need to choose an integer value of x
how is that going to benefit me
such that brackets 2 and 3 don't follow
do practice exam from Pmod its the best school in perth
hardest exams are better
trust me
pmod doesn’t use WAEP and im going to do a WAEP exam
no it’s not i have like 4 friends that moved in like year 9
to like hale or ccgs
ccgs uses waep
for chem and physics especially
oh
I already did it
How did u go
it was kinda easy except for that optimisation on non calc
I think calc was easier than non calc
there was more interesting questions compared to the old ones
did you get that one in your exam?
yes
no fucking way
like the structural integrity of a log is measured by ayx^2 or something
I skipped it didnt know what the fuck to do
had like 4 variables
yea same
i did the first part
and then skipped b and c
but i answered everything else
I reckon 90+
wait and that last probability question
idk why
was a bit strange
at tc the tests are harder than the exams
in year 10 we did year 12 spec
bro what?
there was year 12 content in our year 10 exam
what was the last probability one?
lol
the prerequisite for spec was 60%
calc
remind me...
idk I forgot
oh ok
i did it last week
high chance that at least one of you is Asian
I did it yesterday hahahah
nah
no tc is full of white people
tc?
we have like 10 aboriginal kids for our indigenous program
oh trinity college
damn
refugee scholarship
yes
jesus all this competition only for most people to get into a uni course that only needs 90 ATAR
what sport
like athletics
what course
our median was like 89 lol
or 88
bachelor of arts or bachelor of science, like it can't be more than 90
I swear every course is 80 or under except for med and law
for art?
drawing shit requires 90+?
I cant lie 90 is easy
lie 67% average
yeah I mean 90 or below
My predicted is like just over 99
I have 3x bonus
hahahahah!
actually it might be like 99.5 because of scaling
dawg what
thank god I didnt chose apps or some of those bs subjects
mine is like 94
spec methods language
u go to PSA?
where is psa?
nah I dont mean like some rural school where they add like 5 atar
but I get 10% bonuses for methods, spec and second language studies
but you can just choose a uni that is out of state and it will be back to like 80 or 85
scotch
oh
I think the highest I've seen for something not crazy like dentistry or advanced or double degree in the degree title
bachelor of mathematical sciences at ANU is 95
Or be smart and not go to uni because 90% of people don't know what they want to do with their lives
:)
are u all in yr 11?
a lot of the humanities and arts are at 80 actually
still light work
just figured you might not be interested in those
lmao I switched from maths to sociology at uni
I'm doing mech engineering bachelor with bachelor of cs probably
something like that
probs UWA
ah okay cool
u at curtin ?
I don't know about Scotch in WA but in Melb your parents can sign you up onto the waiting list as soon as you're born
i found our y10 exam omd
no not a WA person
i got like 73 on this 😭
oh ok
but yes Aussie ofc
oooh yr 10?
I was gonna say this is piss easy
there was some shit like this in the methods remember?
that's actually normal for year 10 advanced
what did you get for that?
its not advanced
mine had different numbers
exactly
its achademic extesnion
calc has u1 spec
yeah, had some matricies though I swear
wait
u mean methods my bad
methods is really easy i feel like
because its just everything we learnt from y7-10
but i cant lie i kinda struggle with spec
not in yr 12
everything is new
if you do maths enrichment in an international school you get this
I got 100 on my calculus test and I knew I was going to cook for year 12, comes very easily to me
for year 10
@echo gazelle do you do chem or phy?
uh oh
don't worry it's 52/80 for an A on this paper
to get A* they combine marks from both papers so you'd need like 83% on average
I'd probably only get like 60 rn
imagine yr 10
no knowledge of calculus
id get 30/80
damn its 75% for one at my skl
a lot of people struggle at that level but it's good prep for y11 and y12
have you done the exams?
yea
both?
yes
have u done spec
easy?
yeah that means it must be curved pretty badly as well
cause I checked, for WACE 75% and higher is excellent
as in you can't get a higher markband
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<@&286206848099549185> I don’t know how to find the total length of the path
A dump truck starts to slide down a serpentine to the bottom of a paraboloid-shaped quarry. The helical pitch of the road is given - this is the ratio of the quarry radius (60 m) to the quarry height (40 m). The dump truck entered the road at a speed of 16 km/h and began to slow down with uniform acceleration at |a| = 2 km/h/s. Determine the final speed of the dump truck if, after driving uniformly at a speed of 1 km/h for 7.5 seconds, the dump truck reached the bottom of the quarry with uniform acceleration in the same time that it had already spent on the descent as a whole. Give your answer in km/h and round to the nearest tenth.
use Pythagoras
yeah I'm not exactly sure what they mean by that
Can I throw a photo, how should the road chart look?
photo would be really helpful. for a normal helix you're looking for the blue length
there is one nuance
Do you want me to multiply the number of such possible turns per resulting blue line?
I'm trying to figure out what's going on with the quarry, i guess it's a bowl shape
Paraboloid. just look on the internet
something like this I think?
yes, such a black line. and now I think how to make an equation to find it
figure out what a is based on the initial radius of the quarry (60m)
and height of the quarry 40
yeah
oh that integral isn't right, we need path length
$L = \int_0^{40} \sqrt{(2\pi r)²+1²}\dd{y}$ i think??
hayley is stateside!!
but we need to count the integral for the general case, suddenly the numbers are different
.
well yes, but figure out what the relationship is between r and y first
Wolfram Alpha doesn't want to solve this
hayley did you purge
isn't it just 60 = a √40 ?
a - is this a helical stroke?
does this equation make sense to you, given the diagram?
Okay, let's go through this equation, but I don't know what we're going to do with A next
well, we'll need it to calculate that integral
I would change this.. from the parametric equations, we replace r with a coefficient u, which is already equal to a*sqrt(ф) where a is the helical pitch and ф is the angle, which was achieved through the parameterization of the circle.
oh yeah that might be simpler
it is necessary to make parametric equations of a paraboloid, I think
and there..to get it somehow through integration, I'm still thinking
dy/dx is a fraction, but 1/∞ isn't .. oh limits
inf isn't a number (in most sets)
tell me how to solve my problem further..
frankly i have no idea what your problem even is
the length of the helix on the paraboloid
this is used in the task, I can't output the formula
@hard crest Didn't you decide further?
This channel will not close..
the cmd is .close
I know
@edgy harbor Has your question been resolved?
@edgy harbor Has your question been resolved?
@edgy harbor Has your question been resolved?
@edgy harbor Has your question been resolved?
<@&286206848099549185>
?
I couldn't figure out an equation for the length of the paraboloid's spiral. how to do this?
are u a girl
not
@lean otter
Do you know about the length of the helical spiral of a paraloid?
i said dm me or no help
💀
Banana who goes to the navy to fail?
alr bro
tell me
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help?
\frac{8}{x+5}-\frac{3}{x}=5
$\frac{8}{x+5}-\frac{3}{x}=5$
jan Niku
thanks
where'd you get stuck
i dont know what the common denominator i can multply is
what?
$\frac{8}{x+5} - \frac 3x = \frac 5 1$
jan Niku
multiply by $(x+5)x$
jan Niku
(the 1 is there, its implied)
that works for all?
well the (x+5) factor will cancel in the first fraction
and the (x) factor will cancel in the second
you may imagine the 1 factor cancelling in the third, if it makes you happier
and now we have no fractions left
now im getting confused
we still need to multply numerator
and denominator
if i have 8/x+5
and i multiply both sides by x(x+5)
i get 8x^2+40x
as numerator
and denominator is
alr
will you give me a moment to type
sure
it might take me a few tries to get it right 
np
$\qty( x(x+5) ) \qty( \frac{8}{x+5} - \frac 3x ) = \qty( x(x+5) ) 5$
jan Niku
ok i see
do you see why I'm using x(x+5)?
yea
its nothing special, just used every denominator multiplied together
alright
now we can distribute
$\frac{ 8x(x+5) }{ x+5 } - \frac{3x(x+5) }{ x } = 5x(x+5)$
jan Niku
yea, and this step, you can do more slowly, if you want
3x+15?
to say only with numerators makes me nervous
8x-3x+15=5x^2+25?
wdym?
it does, but do you understand how the distribution happened here
yea
i mean, i just want to be sure
okay
if you feel you could duplicate that step then you are good
it does, by design!
yea
since we mutiplied by the product of denominator
so 3x+15 ?
they will all cancel with part of what we multiplied by
after the x cancels out
yes
what am i doing wrong?
you made a small sign error
-15?
it should be $\frac{8x}{1} - \frac{3(x+5)}{1} = 5x(x+5)$
jan Niku
so $8x -(3x+15) = 5x(x+5)$
jan Niku
yea, easy mistake to make, you hae to be careful
whats up
does this strategy work for all problems like this one?
where i multiply by both terms?
the thing we multiplied by
yea
but we would use different terms because diff denominators?
ok so i can use that in other types of problems
ok and one more thing
do you know where i can learn probability and statistics?
like a guide out there
thats a tough question i would say you should take a class or find a tutor
i only need it for alg 2
alg 2 probability and statistics
and i dont have a class or a tutor
well thats a pretty broad topic
you could try an online course, something on youtube
there are free courses out there
can i show u a preview of what im looking for?
okay
like a set of problems
alr
@marsh walrus for stats https://www.jmap.org/Worksheets/S.ID.A.4.NormalDistributions1.pdf for prob https://www.jmap.org/Worksheets/6.SP.C.7.ExperimentalProbability.pdf
these problems are what would be covered in a normal introductory probability and stats course
im not sure what to say other than that
should i try khan academy?
the material is generic; if you find some intro prob stats course, this will be covered
lets see
looks up up to unit 12
i would say all but unit 13 onwards
really?
who needs help with math?
it normally takes people a while to like
internalize the normal distribution stuff
who needs help
probability i think is more straightforward, for people
i have some background so its not completely new
probability i find harder
ah
but its all good
you're backwards 
haha
well if you have funn prob problems i can help with
i like prob
stats is spooky to me
thanks jan
np
if u want a preview tho
good luck
Do u need help sir?
why are u chatting here if u dont need help..
huh?
yea
Then dm me i can help
thats honestly almost all i see
@lean otter usually we dont do stuff in dms
people have their own channels
i dont know wthat that is tho
oh yea for those ones
you just gotta practice

but fun exam
it looks harder than any algebra class i ever took
what? no way
my algebra classes were easy it was the later classes that were murder lol
im sure youll do great
you too
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can i please get help on number 13🥹🥹
ive been trying to solve it for almost an hour now😂😢
it feels like the area should depend on the radius of the circle...
and not be constant
cus i think i got a formula for the thing but its a wierd formula in r
Let AM = r and MB = x
and PB = t
we know r + x = 2
also BM.(2AM+BM) = PB^2
=> x.(x+2r) = t^2
therefore 4-r^2 = t^2 (as r+x = 2)
now, angle apb = 90
so area of triangle apb = 1/2 * r * t
and area of sector AMP = pi r^2 . theta/ 2pi
where theta is angle PAM in radians. but sin theta = t/2
thus the area of the shaded region is the triangle area - the sector area
$= \frac{1}{2}\cdot rt - \frac{1}{2}\cdot r^{2}\theta$
CherryMan
$= \frac{1}{2}(\sqrt{4-r^{2}} - r^{2} \arcsin(\frac{\sqrt{4-r^2}}{2}))$
CherryMan
by substituting in the vlaue of t as sqrt(4-r^2) and theta as arcsin(t/2)
and this doesnt look constant
@outer compass pls check if ive made a mistake in the process
$= \frac{1}{2}(r\sqrt{4-r^{2}} - r^{2} \arcsin(\frac{\sqrt{4-r^2}}{2}))$
CherryMan
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I have a quick question about matrix calculation with unknowns, for example, what techniques are there to determine what values for a give what solutions?
I can use gauss-jordans and then see what values a might have to get trivial solutions for example
well it could be anything
what is the question asking?
like a particular solution?
But the solution states that since 3-3a =/= 0, so a =/= 1
How do they find this "3-3a"
!original
Please show the original problem, exactly as it was stated to you, with the entire original context. A picture or screenshot is best. If the original problem is not in English, then post it anyway! The additional context might still be helpful. Do your best to provide a translation.
yoooo bungo
been a while
hey ren
the picture space, I am translating directly
i guess it means image?
Probably
ok, do you have any thoughts about how to do that?
Gauss Jordan, see what values of "a" would create leading rows of 1s
or 0s
and then the solution would be different cases of different values of "a"
Yeah
I think it works, but I am more so curious what the solution is pointing towards
I could not find this when doing gauss jordan
I would expect to find it there, so either I did it wrong or they're using another technique that I am not aware of
well do you see that if a=1 then you get 0 0 0 for your last row when you do the gauss jordan?
Yepp, I agree
I guess I am asking if there's a more direct way to find this
Because the solution seems to allude to this
well, if you happen notice that when a=1 then row 1 + row 3 = row 2, that could be a shortcut
but in general it's not easy to notice such things
if you know about determinants, you could use that
I am aware about how to calculate them but not sure what they mean. I should read more about determinants, thanks
Yes that's fair
short story is, if the determinant is 0 then the matrix has linearly dependent columns
so you could find what value of "a" makes the determinant 0
Ooh, this is where it's from then
Surely
I bet if I calculate the determinant it will end up as 3-3a
possibly, give it a try!
awesome thanks!
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hello, I need help with the following: suppose $a_n$ is bounded and $\lim_{n\to\infty}(a_n-a_{n-1}-a_{n-2}) = 0$, does that imply $a_n \rightarrow 0$?
ω
I think it does
and since $a_n$ is bounded there exist $\limsup a_n$ and $\liminf a_n$.
ω
$|a_n-a_{n-1}-a_{n-2}| < \epsilon$
ω
okay...
limsup and liminf are not linear btw
eg limsup(an + bn) != limsup(an) + limsup(bn)
note that if a_n has a limit then it must be 0
I know that
oh yes I see from the expression
makes sense
so if u prove a_n has a limit ur done
yeah
have u tried to think of a counterexample?
yeah, but I couldnt find one
let's say u believe the statement is true
try to find a counterexample and see what goes wrong
and try to find it properly
the counterexample must be a bounded sequence which does not converge
what's the simplest such sequence?
$(-1)^n$ comes to mind first
ω
it's becaue an - an-1 - an-2 doesn't converge to 0
oh sorry I worded it poorly thats what I meant
maybe try a limsup liminf argument like u were suggesting
use limsup(an + bn) <= limsup(an) + limsup(bn)
gtg
alright
to show that limsup an = liminf an maybe
yeah that would do it
@outer river Has your question been resolved?
ω
@outer river Has your question been resolved?
can't do just do it on contradiction? suppose $a_n \to k \neq 0$, then $\lim_{n \to \infty} a_n - a_{n-1} - a_{n-2} = \lim_{n \to \infty} a_n - \lim_{n \to \infty} a_{n-1} - \lim_{n \to \infty} a_{n-2} = k - k - k = -k \neq 0$
Sires
we already established that if its convergent then it is convergent to 0
yeah but I was trying to do contrapositive assuming it already converges
I believe the following is a counterexample:
$a_0 = 1, a_1 = 1, a_2 = 0, a_{n+2} = a_n - a_{n+1}$:
1, 1, 0, 1, -1, 2, -3, 5, -8, 13, -21, ....
Sires
probably easy to prove that from a_3 onwards its an alternated fibonacci sequence so it does not converge
is $a_n$ bounded?
ω
oh my bad
forgot about that
oh ok
but that can still be helpful
because that is the only way to construct a sequence that obeys the hypthosis given the first terms
nvm I'm halucinating
its just the only way to make one where the sum of 3 successive terms is always 0
yeah
@outer river Has your question been resolved?
@outer river Has your question been resolved?
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How do you find W, W^2, W^3 and W^4 for a.ii
A is the distance from center
Pi/4 is the orientation angle
So if a =
2
Since pi/4 represent the diagonal in the first quadrant of the unit circle
You can represent w
And for w^2, you take 2e^i*pi/4 and you put a square
This gives 4e^i*pi/2
And same you can draw it
Yes
I already got the stuff for W3 and W4
Its just im unsure what to do next for the drawing
Like im not sure how to get here
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Does this proof relies on the existence of f^-1, that is, is it necessary that inverse function exists, or inverse image existing is sufficient
they used only the preimage
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ive tried taking logs on both sides, but im not sure how to proceed from there
@vague pewter Has your question been resolved?
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Prove the inequality 10(x^2 + y^2) + 3(x + y) - 8xy <= 18 for all numbers x, y ∈ [0, 1]. Hello, please help me solve this inequality, I had many attempts to solve it, but unfortunately nothing worked out for me, I will be grateful for your help
try taking the function is equal to 18 and apply implicit differentiation to show dy/dx is 0?
not sure if this works but seems to be worth a try
ok i correct my sefl
Thanks for the answer, but is it possible somehow without the derivative?
err
its like 10(x^2 + y^2) + 3(x + y) - 8xy=k is a relation
you can either implicit differentiate which yields 20x+3-8y=0 at a max point, take this back to the original function so its all x or y and then it'll be easy to find the max
or you can try to transform the relation into a function of y= something x with a k which could still probably yield the same result
Why is there a maximum here?
because the question asked to prove a max?
no
i dont know. derivatives are the first thing to come to when its max and min questions
probably
you need to prove that the inequality is true when x,y belongs is from 0 to 1
This is an inequality with 2 variables, why introduce a derivative here?
ok ok i get it
you can look at this function like 2 relations
10y^2+3y-8xy and 10x^2+3x-8xy
we wanna make both as large as possible so the whole thing is largest
we look at them separate, so in the first part only y is variable and in the second part only x is variable
you would yield -5y=3-8x and -5x=3-8y when both of these are in maximum
take this simultaneous equation and you find there is actually a solution x=1 y=1 that falls wthin the domain
take that back and the function yields 18 which is max
i am skeptical of the -8xy here
@sturdy stone Has your question been resolved?
I don’t understand what you want to do, why don’t you just show it???
you can view the left hand part as a parabola in x on interval x∈[0;1]. Its branches go upwards, so, the maximum value is reached only with x=0 or x=1. So you plug these into initial equation and find the maximum w.r.t. y. which is always <=18
for the same reason it is enough to check only y=0 and y=1.
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straight to the point: Find a cubic polynomial equation with roots -2, 2, and -4., i have absolutely no clue how to do this
How would the factored form of such a cubic equation look like?
p(x): ax^3 + bx^2 + cx + d
that's not factored
Factored form is e.g. something like this:
(x-2)(x+3) = 0
now you can either expand it if you want it in the standard form, or keep it like this
how can i expand it?
fortunately, multiplication is associative
(x+2)(x−2)(x+4) = ((x+2)(x−2)) * (x+4)
so you can start by doing this: (x+2)(x−2)
and then take the result and multiply it by (x+4)
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@hollow zenith Has your question been resolved?
yes but still confused just got the answer
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did I do anything wrong
bc the answer shoudl've been
a = 2
b = 3/4
c = 41/8
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Bit lost here
Thinking of trying to rearrange the cos^3 theta such that i can replace the 12 sin theta in y with x
its not working out all too well for me
well i guess you could probably just use the generic equation that $$\int y \dd x = \int y \frac{\dd x}{\dd \theta} \dd \theta$$
I can't believe you've done this
oh idt i've come onto that yet
oh ok so ig i try differentiate cos^3 theta
oh right the d theta cancels out
nice
thank you
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I posted first 😤
go into another channel ya goof
yea what is wrong ?
So do you have sin and cos in your x equation because the roots are imaginary?
well yea
in general it's c1 exp(r_1 t) + c2 exp(r_2 t)
but since the roots are complex, cos and sin appear
hmm
there's also a formula omega=sqrt(k/m)
I think that's phase shift?
does that go into the formula anywhere?
because I thought you would have cos(omega*t) and sin(omega*t) but that doesnt seem to be the case
for a damped harmonic oscillator, the differential equation is :
x''(t) + c/m x'(t) + k/m x(t) = 0
with m the mass, c the damping coefficient, k the spring constant
k/m = omega²
omega would appear indeed in the solution if you solve it
wait, can you also write it as mx''(t)+cx'(t)+kx(t)=0?
because thats usually how i see it
you can
i just divided both side by m
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Im so lost, idk where to even start, like their are 2 variables in this, how am i suppossed solve this?
do you know what a quadratic whose only solution is 4 would look like?
or whose only solution is 3, or 2, or 1
or 0
uhh, nope
if a quadratic has only one solution, then b^2 - 4ac = 0
don't you agree that if a polynomial $x^2 + mx + n$ has roots $r_1$ and $r_2$ then it's gonna be equal to $(x - r_1)(x-r_2)$?
combinatorics hater
yes
substitute x = 4
oh wait
sorry
yeah thats what i did lol
since x is the only solution
both roots are equal
sum of roots is 4 + 4 = 8
product is 4 * 4 = 16
now the reason we are taking it as two roots instead of a single 4 is that in a quadratic equation with all real coefficients the roots can only occur in two multiples
which is either none or two
here there is one
so only possibility is it to have two roots
and from here maybe @lucid trout can continue?
nop
oh
😔
well theres nothing more anyway
just that sum of zeroes is -b/a and product is c/a
for ax^2 + bx + c = 0
i thought you were about to derive it
so here can you find what b and a are?
yea
by comparing
b= -8
yep
so b = m = -8
when is says, "only x value" it means the only root is 4?
yes
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I feel like i should know this but, sm how I'm not getting the correct answer.
My thought process:
I got 8 for how many combinations of shirts and pants
1S 2S 3S 4S
1P 1P 1P 1P
1S 2S 3S 4S
2P 2P 2P 2P
P = Pant
S = Shirt
Then i js used the formule
*formula
8 options(n)
2 to chose from(r)
8!/6!
= 54
becuase it is a permuation + no repeats
I'm thinking that either, I didnt understand the problem and it is actally Combinations + no repeats, or I messed up with the shirt pant combos
hello
hello
slight inconvenience
you may have choosed two combinations with 1P
or 2P
in one of those
so instead
you can just calculate for shirts
and then multiply by 2
as there is only two ways you can display the pants
wdym
like i counted a combo twice?
@frosty stag Has your question been resolved?
i dont think you can choose the same pant twice
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i feel so silly for asking this but i literally forgot how to divide by a decimal
represent the decimal as a fraction
dividing by a fraction is the same as multiplying by its reciprocal
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could someone explain?
this is the definition of lim in sign function
epsilon > 2
therefore, limit doesn't exist
okay but why tho
could someone explain the definition of limits in simple terms?
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@dense sphinx Has your question been resolved?
=( Anyone?
@dense sphinx Has your question been resolved?
It negates the definition of limit existing
You have to first understand the eps delta definition of limit it looks like
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Having trouble with convergence and divergence. Trying to solve 75
the directions are cut off a bit
Give me a sec
have you found the general term for a_n?
No how would I go about finding it? Would it be sn?
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the height of the tower doesn't matter but the location does
yeah thats the part im trying to think of
unless youre a flat earther or something
this is not the formula i really want though
we dont know the tangential speed of the eiffel tower
What info are you given?
what you want is omega = 2pi*f
oh wack
0.8552 rad latitude
frequency
whoever gave you this question expecting you to know the exact latitude of the tower is evil
but also this is 3 dimensional so i dont know what to do here
Result:
0.0041666666666667
hm not right
no clue
i would answer c and be like really confident
there's no way the yearly motion changes the answer enough to matter
and latitude doesn't do anything
yes, it's just the same thing as rpm, except unit
how many circles per second
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" The angular velocity of the Earth is approximately 7.272×10−5 radians per second."
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Could someone tell me why my particular solution won’t work.
roughly speaking, Axsinx + Bxcosx generates some sinx and cosx terms that cannot fully be accounted for by the Axsinx + Bxcosx term itself
in general, when you have xsinx or xcosx on the rhs and you wish to use undetermined coefficients and you confirmed the homogeneous solution doesn't have any overlapping terms, your guess should look like (Ax + B)sinx + (Cx + d)cosx
Strange, this is the first example I've come across that has required that. Even if my homogenous solution has c1cos(x)+c2sin(x) I've always been okay with a particular solution of Axsinx+Bxsinx
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Wait I need help how is this wrong 😭
the average velocity between 2 points is the slope of the points' secant
the average velocity only depends on the start and the finish
it doesnt matter however the graph behaves; as long as they have the same endpoints, the average velocity is still the same
it's the slope between the endpoints
Ohh I see
Tru
I thought I could use any point from the graph
Also if distance is 0 till 10 secs and then suddenly distance reaches 100m then also avg is same bcz avg is total distance/total time taken
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Im not able to understand how to prove q2
Blockydude
I got question 1 by doing the above part
Is this a misprint? It seems surprising to me that the centroid about x and the centroid about y would be exactly the same no matter the shape of f.
It's been a long time since I've done multivariable calculus seriously though.
yk it actually might be, i've spent nearly an hour on a whiteboard and its constantly showing x^2 f(x) instead of xf(x)^2 and chat gpt agrees
its not even multi-variate calc im in calc 1
our prof just likes making our life harder
ChatGPT agreeing is not worth much in general
true
its not a typo turns out, my prof has a published list of typos and its not in it
now im even more confused
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What is the probability of four of a kind in poker ?
I saw a video where it is 13C2 x 2C1 x 4C1 and the "story" behind this is that first we are choosing out of 13 cards 2 , say A and K , then we are choosing which one will be 4 jn number and the we are choosing the colour
what kind of poker? do you mean what is the probability of a 4 of a kind in a single draw 5 card hand?