#help-43
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try it!
so the answers are k=10 and k=-10
check by substituting
nps!
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Just studying for this and I'm confused on something. When we do 2/3 - 5/6 we do 2 x 2 and 3 x 2 to get 4/6 - 5/6. But when we get to 1/7 - 4/3 we multiply both sides? so i just want some clarification on when we Multiply Fractions on one side and when we do it on both sides by different numbers?
the idea is always that you want them over a common denominator to add or subtract them.
the common denominator has to be a multiple of both denominators involved.
in "most" cases, the simplest one is just their product (as in the case of 1/7 - 4/3, where you take 7*3=21 for the common denom and work towards that)
but in the case of 2/3 - 5/6, you can notice that 6 is actually already divisible by 3 and so you can take 6 as the common denom (and this looks like not touching the second fraction).
Oh okay I think i see it
I have my study notbook rn should i write down as a mental note that as
in simple terms Multiply the denomiators by themselves To get a number then work from there?
i don't like that simple-terms phrasing
but i don't know if i can offer you one
i tried to make it as simple as possible for you
okay mb thank you for that 😅
Are you aware of cross-multiplication
If you are, then remember to do that, that's all
so when i have 1/7 and 4/3 just cross multiply?
Yes, add the numerators and multiply the denominators
yes it comes from $\frac{2}{3} \cdot 1 - \frac{5}{6} \cdot 1 = \frac{2}{3} \cdot \frac{6}{6} - \frac{5}{6} \cdot \frac{3}{3}$
so essentaly It does matter if it 1/7 - 4/3 add the numerators and multiply the denomiators
but 3 * 6 = 6 * 3 so you can combine the numerators, same denominator
south
no no, the sign stays, so it there's a minus then you subtract the numerators
that's not clear
yeah then, what do you get if you do this
but then you subtract the numerators instead of adding
not -3
like using this criss-cross method, you get 3 and 28 right
Oh i see where i messed up i did 7 x 3 and not 7 x 4
ahhh yeah
so yep, you get (3 - 28)/21 = -25/21
that explains it
alright i made a note for the cross multiplaction steps to not mix that up
then i see where it goes from there
cool! if you're done type .close
OKay also im really sorry for this i see where the 3/28 comes from
but where the 28/21
are you forgetting that you're multiplying the numbers like this
so 1 * 3 = 3
7 * 4 = 28
the denominator is the product of the two denominators, so 7 * 3 = 21
Oh crap my bad
that's ok!
ok im just write some notes done and thats it
Thank you all for your time and help
😅
Made some notes on the cross multiplaction where its 1/3 to get 3 then 3 x 7 to get 21
then 7 x 4 to get 28 and 7 x 3 to get 21
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hi im wodering if the value of x is 67 or not?
67?
yea
fellow Malaysian 👀
could you show your working please?
eh how yk in malaysian
x+36=103
x=103-36
x=67
language?
kan ada bahasa melayu kat situ
i'm more than familiar enough with typical Malaysian secondary school workbooks even though i don't do them as often as i should
hot take: those are not that good
i think it might be right based on alternate segments
make that a based take. you're talking to someone who never tried any of them
so its correct?
but whats the purpose of it saying the congruent
wdym?
yeah its correct
the question say angle pqr and pts is congruent
thankss
well it's not needed for part a perhaps, but that's only part a
could be needed for future parts
ohhh okayy thank youuu
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,rccw
Prathmesh
Alexis_Fx
yeah thnx
AlmondAxis987
$f(x) = x-x^n$
AlmondAxis987
$F(x) = x^2/2 - x^{n+1}/(n+1) + C$
AlmondAxis987
$F(x) = \frac{x^2}{2} - \frac{x^{n+1}}{n+1} + C$
Alexis_Fx
for general n you should get $\frac{n-1}{2(n+1)}$
Bronze Jade
$An = F(1)-F(0) \ An = \frac{1}{2} - \frac{1}{n+1} - 0$
AlmondAxis987
$An = \frac{n-1}{2(n+1)}$
AlmondAxis987
$A_2 A_3 A_4... A_{n-1} A_n = \frac{n-1}{2(n+1)} \frac{n-2}{2(n)}\frac{n-3} {2(n-1)}... \frac{1}{2(3)}$
AlmondAxis987
so we see that we have n-1 terms (as we go from A2 to An)
and All (n-k) after n-1 cancel out with numerator
so were left wiht 2^(n-1)(n)(n+1) in denominator
and 2 in numerator
so it becomes
$\frac{2}{2^{n-1}(n)(n+1)}$
AlmondAxis987
AlmondAxis987
uhh, you shouldn't have solved the problem
As a helper, please do not give out answers that could be copied as a homework solution. Have the student work through the problem themselves and guide them along the way.
It's okay, I didn't want to interrupt
@kind glen Has your question been resolved?
It clicked me when you did this, but still thanks for solving the whole question
ur welcome
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!status
What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
Computation, computation and computation
1
do you know what the symbol $\circ$ means?
Ann
yes fun comp
Ann
yes
ok so go and calculate that then
... there wasn't any need to post the question again
46
great now do the other two as well
72
9 div 6?
Seems good
are you trying to ask me a question?
No
if you want to ask something then you have to phrase it as a complete sentence.
i do not know what "9 div 6?" means.
what is the definition of divisi
T-T
Also its 6 that has to divide n not the inverse
"divisi" looks like a word that's half-eaten
, I mean, what is the definition of divisibility?
if the remainder of the division is 0
remainder*
also let's try to help renato develop such useful life skills as:
- googling
- looking shit up on wikipedia
only y | x
is the divisibility relation symmetric?
not at all
what do you think, renato
i'm gonna throw your question right back at you: is the divisibilty relation symmetric?
i dont understand why rhey sawp places for example, y div x is written x | y and x div y is written y | x
the | symbol is read as "divides", and "x divides y" means the same thing as "y is divisible by x".
it is the same relation written backwards.
why this switch even exists, i unfortunately can't answer as i don't know the history of it.
is confusing
to say the very least, any tips?
any tips on remembering?
whats the reminder of 9/6?
are you seriously asking others to do division...?
Result:
1.5
remainder
9 is not divided evenly by 6
a reminder is something you put in your phone calendar to remind yourself of a doctor's appointment
a remainder is something that remains
yeah exactly
anyway surely you know division with remainder? like that's a school-level topic. maybe around age 10 is when you learn it in school
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could someone explain how to go about this question
ive tried to solve it but only now that i have finished my working out i realise i was completely wrong lol
initially the bowl contains 4 oranges and n-4 apples
if you want the bowl to be left with n-6 apples, what 2 pieces of fruit will you have to take from it?
orange
i thought the opposite lol

do you mean "two oranges"?
the only possible answer options are "two oranges", "two apples" and "one of each" btw.
i think either you're overthinking it or not reading me correctly
are you absolutely sure
Initially, the bowl contians 4 oranges and n-4 apples.
I take 2 oranges from the bowl.
How many of each fruit remains in the bowl?
(answer as a complete sentence)
the bowl contains 2 oranges and n-4 apples
i took no apples out and also didn't put any in, and yet the amount of apples changed?
how did that happen?
@cedar hawk
right...
so taking out 2 oranges does NOT get us to
if you want the bowl to be left with n-6 apples
because after that there's still n-4 apples in there and not n-6...
yes, glad we could come to that conclusion finally.
yes, you have to take out specifically 2 apples.
thats what i though initially
then i continued to solve and got to some quadratic
but my answer was not 10 as shown
if you could have sent your entire line of work here, we could have probably already figured out where your mistake is.
is this where i'm supposed to start looking
yes or no
@cedar hawk are you still here or what
yeah my bad for the non sequential working out
ok, then why's there an n at the beginning of the LHS?
thats the number of fruits in the basket
but why are you multiplying it with the probabilities...
like i can see (n-4)/n is P(first drawn fruit is an apple) and then (n-5)/(n-1) is P(second drawn fruit is also an apple)
but what's that n doing there afterwards
and you didn't think to show me your diagram...?
but then again the question of "how tf did that extra n come in" still stands.
like actually let's work this expression out for some specific value of n without concern as to whether it's equal to 1/3...
,calc 1000 * 996/1000 * 995/999
Result:
992.01201201201
this gives you a number greater than 1, so you know it cannot possibly be a probability.
my point is this
i was hoping you would tell me your reasoning for this n so that i could dissect it and tell you where exactly you went wrong.
but you didn't or couldn't give me that.
its just that usually in probablity tree diagrams you strat with multiplying the number at the very beginning
what number at the very beginning
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bmo1 2023 q2
are u allowed to just prove the contrapositive? that given a_0 and a_1 are not consecutive then a_2023 and a_2024 are not consecutive? it's nowhere in the markscheme but it seems a lot easier to me
yes u are allowed that
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yes
Ok thank you!
pls dont use x for multiplication
yes
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or just put them in parentheses
Alr
(3^3)(y)
I mean putting a dot would take less time than brackets
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hey all, im trying to understand if this infinite series is convergent/divergent
so i was trying to first find a finite Sn and see if its divergent or convergent, but couldnt find so
any hint will be wonderful
have you tried partial fraction decomposition?
spoiler: ||you should get a telescoping series||
where tho
I like astronomy that's the hint I would give you
1/(k^2-1)
i mean how come they expect me to come up with that idea, i guess its the experience that tells u so
because k^2-1 factors and i know telescoping series
it's not guratneed but mostly works
Because why not trying since it is easily decomposable
actually im new to partial fraction decomposition so..
You could use a test then
Like ratio test or something
For me it is trivial that it converges bc it is essentially the armonic series with just -1 in the denominator so that essentially does not change anything and it must be convergent. That idea might be useful
Partial fraction decomposition can give you the sum but you just need to prove convergency
you can also just compare it to 1/k^2
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harmonic series diverges
unless you meant something else
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Is this series convergent or divergent? Normally I would use the limit comparison test, but that doesn't work with complex numbers.
@bleak flower
it can still work if you take the absolute values nvm
thats a good one ty
you can use this to prove something converges but not that it diverges
would it be valid to multiply by complex conjugate then splitting into real and img sums
Probably
What do you mean by this?
that will work
a series converges if and only if both its real and imaginary parts converge
I means multiply and divide by (n^2-4i)
And I just want to check my working out for this limit:
|Re(z)|^2 / z
= |x|^2 / z
= x^2 / z
<= [(x)^2 +y^2 ]/ z
= z_bar * z / z
= z_bar
= 0
Therefore using squeeze theorem, the limit is 0
You can't do inqualities with complex numbers
You would have to write |z|
Fair enough. I dont' know how to do it then
z_bar • z = |z|²
Why don't you use the ratio test?
That looks too complecated for that series. I didin't even want to try
But I guess I can try
Are you suggesting I do basically the exact same thing, but initially multiply by z_bar/z_bar?
Wait that changes nothing
I'm not 100% sure what you are implying
Yeah but how did you get the denomenator to be |z| instead of just z?
because that's how squeeze theorem works with complex functions
you take the absolute value of your function
But then you are not solving the same limit?
It feels easier to just multiply and divide by the conjugate, that is n^2 - 4i and then split into imaginary and real sums, then show that the imaginary sum diverges
Yeah I figured that one out thanks, but now I am stuck on this limit
If |f| <= |g| and g goes to 0 then f goes to 0, because we know that for all epsilon there exists delta such that
|g| < eps, so by that there exists a delta such that |f| < eps, for all eps.
Are you convinced now?
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Can anyone give me a nudge in the right direction as to how I can do the proof question in the challenge section? Part a specifically
,rccw
I dont really understand where to start, so I just subbed in values for a and c as 1 and 1
Have you learnt about discriminant?
Generalized harmonic series with exponent greater than 1, sorry. That's what I meant
this is a good start :) we need to "choose a value of b," so can you solve this inequality for b?
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I am stuck on the first line of this proof. Why is that series convergent?
This is how my notes define it. Note it only has to be convergent at |z| = r (not <= )
So I get why it would be convergent for some R1 < R, but I don't get why it is for z element of B_R1(0)
well R1 is less than R, so it's less than the sup of that set
which means there exists some z with |z| = R1 and the series converges
you need to show that in fact for any z with |z| = R1 the series converges
I feel like at the beginning where the textbook uses |z1|, the past test should be using that R1, but it just uses z
Idk the proof in the textbook makes way more sense to me
Ohhhhhhh thank u
I get it now
This is why I like maths yk
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is it converging, and if it is what does it converge to cuz denominator contains an imaginary unit
already closed you have opened a question
@short jewel Has your question been resolved?
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i was watching this yt video and this guy was teaching kings rule property and he said the shortcut is the answer comes to be (upper limit - lower limit)/2
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can someone explain this to me.... I do have some work but i dont think its working out lol
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oops
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Divide a triangle with angles of 15°, 105°, and 60° into three equilateral triangles.
🤔🤔🤔
That's going to be slightly difficult 🙂
but any way we divide it theres gonna be an angle <=15 right?
yeah
I'm wonder how're we gonna do that
There's certainly "cheaty" ways
We can't divide 15 degree angle smaller but we also can't add
E.g. cut out pieces and rearrange them.
But yeah, that's wouldn't be just "divide", it would be "divide and reassemble".
I somehow got two triangles and not 3 lol
same lol
i mean its impossible without reassembling right
Yes
are we allowed to reassemble pieces
yes ofcoure3
try to create an equilateral triangle from the given 60 and see what you can do from there
hmm ok
i thnk i got ti
a lot of construction
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Fk
a....a.. square root
How am I supposed to mental math this
sqrt(10000) = ?
you mean removing the sqrt?
100*sqrt10
It is 10^2
Fk it is 101^2
Modulus I get it
I feel stress when doing this quiz
My mindset has changed
I used to feel relax when doing it
this is easy
What my mind try to tell me
I think so
See -14c will never result in something that has 5 as the last digit
I actually solved that one with my teacher
I think I got it now
Damn
I feel tired easily
I cannot do academics for too long
Properly 4 hours a day is ideal
5 is a bit too much
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Am I on the right track to finding the answer to no. 87
The question is to the left underlined in pink with the direction up top
good start
And I can’t simplify the radical 21 anymore right?
oh wait yeah i thought that was a remnant of something else
That’s just a show of what I need to find i forgot the equal sign
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is this question even posible?
yes, if there are 2 equations (which aren't just the same one but multiplied by a factor), you can find the exact value of any 2 variables
picture it as 2 lines intersecting
my answer is (2401/195,9/5)
i didnt simplify btw
is it correct?
wait
i think it is wrong
show your work tho
there's a lot of places where you could mess up your arithmetic here
for 3 variables, you can picture this as a 3d space. where each equation becomes a straight sheet of paper. with 3 sheets of paper, you can find any exact point
note: they can't be the same equation twice
I dont think this is necessary. its just the same plane twice
because the answer i got is (2401/405,-2158/135)
btw it just take too much time
will it be better if i just write decimal if the fraction is too big?
i just always use fraction. and its fine to always use fraction. cuz writing down decimal might take more work.
but both will also accepted right?
unless it ask for specific one
make sure the fraction is simplified ofc
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is my answer correct the table below
<@&286206848099549185>
real
if you're just asking for whether you filled the table below based on graphs, yes it seems correct
yes im asking that
thanks
I have another one
how about this one
<@&286206848099549185> im asking if i filled the table below correct hehe
yes
it is
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I'm not getting anywhere close to finding a multiple of 5
in the equation 3*2^2n + 2*3^2n
thats not an equation
thats an expression
stop using the word "equation" to refer to things without an equals sign in them
anyway: consider that 2^(2n) = 4^n and 3^(2n) = 9^n
oh ok
yeah?
also to be clear i am going to push the modular-arithmetic angle
4^n + 9^n is not equal to 13^n...
your expression equals 3 * 4^n + 2 * 9^n
your blue hint says 4^n ≡ (-1)^n (mod 5)
do you see how to extend this idea
you are overthinking it
4^n can be expressed as (5-1)^n
oh
i still dont fully understand how that's going to help
try expanding out (5-1)^n (mod 5)
unnecessary
there's no need to that considering you were explicitly given the result of it
the problem sheet already gives 4^n ≡ (-1)^n (mod 5)
which is this
we can circumnavigate the world to rearrive at that
but in the interest of not wasting 80+ days
let's not do that
wait so
how do i use this though
if this is "overcomplicating"
what is 9^n congruent to mod 5
like you're technically correct but how did the +5 happen
what i meant is
4 and 9 are 5 apart
4^n ≡ (-1)^n (mod 5) because 4 ≡ -1 (mod 5)
so the modulus would be the same?
and by the same token, since 9 ≡ -1 (mod 5), so too do you have 9^n ≡ (-1)^n (mod 5)
thus your original expression
3 * 4^n + 2 * 9^n ≡ 3 * (-1)^n + 2 * (-1)^n ≡ ? (mod 5)
okay
ah
that's 5*(-1)^n
yes
so the modulus would be 0?
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$u=\sqrt{t}$?
Allen
show ur work
u sub i guess
Integration by parts?
!nogpt
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U sub still leaves two bits tho
!nogpt
Please do not trust ChatGPT or similar AI tools for mathematical tasks, as they often generate output which "sounds correct" but has numerous factual or logical errors. Use of these AI tools to answer other people's help questions is strictly against server rules (see #rules).
sry i ment i am saying it should be -1 and gpt is telling -1
my work isnt pretty thb
$$u=\frac{1}{\sqrt{t}}$$
$$dv=e^{-2\sqrt{t}}dt$$
just tell us what you did
ImOakley
ok so everything up to the last integral seems right
now lets think about it
i calculated 1
You used e^-v
Whats the antiderivative of e^(-u)? @worldly ermine
That doesnt work
just u sub $u=2\sqrt{t}$
Allen
i need some time to write out my steps
wait i need to google i dont do maths in englisch sry
what language
okok
german
@worldly ermine
-e^-u+c
correct
oh
but thats not what you did
$$\int_{0}^{\infty}\frac{1}{\sqrt{t}}e^{-2\sqrt{t}} dt$$
$$u=2\sqrt{t}$$
$$du=2\cdot\frac{1}{2\sqrt{t}} dt=\frac{1}{\sqrt{t}} dt$$
$$dt=\sqrt{t}du$$
$$t=0\Rightarrow u=0, t=\infty\Rightarrow u=\infty$$
$$=\int_{0}^{\infty}e^{-u}du$$
$$=-e^{-u}\Big|_{0}^{\infty}$$
$$=-e^{-\infty}-(-e^0)$$
$$\boxed{=1}$$
@worldly ermine u see now?
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ok I’ll continue writing anyways
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Allen
$$\int_{0}^{\infty}\frac{1}{\sqrt{t}}e^{-2\sqrt{t}} dt$$
$$u=2\sqrt{t}$$
$$du=2\cdot\frac{1}{2\sqrt{t}} dt=\frac{1}{\sqrt{t}} dt$$
$$dt=\sqrt{t}du$$
$$t=0\Rightarrow u=0, t=\infty\Rightarrow u=\infty$$
$$=\int_{0}^{\infty}e^{-u}du$$
$$=-e^{-u}\Big|_{0}^{\infty}$$
$$=-e^{-\infty}-(-e^0)$$
$$\boxed{=1}$$
u the goat
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uh oh
ChatGPT stupid
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number 6
what exactly is the initial condition like, im so confused
yeah
it doesn't look like an initial condition for sure
idk
prolly a misprint maybe
anyway, just wanted to confirm that im not dumb
thank you
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is this correct?
Yes
(don't forget the dx's for the integrals
)
@worldly ermine Has your question been resolved?
ok thx guys
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Hello I need help with some of these questions I feel like they will be on my test and indont know how to like do them, also yes they are ch!tg!t but I asked him to create question
For the first one
Ik u can just plug in the values and solve for b and a
But like the second one I'm a little lost
The 3rd one I would just do the same as the first
Same with 4th
But I don't get the last one
well, for the second one, after 9 days 0.6 * 0.6 * 0.6 (since it decays by 0.6 every 3 days) of the original is remaining
so look
Wouldn't it be plus
let's say the original is x
yes
after 3 days, we have 0.6x
oh yeah
but after 3 more days, we have 0.6 * 0.6x
Ahh
and after 3 more, 0.6 * 0.6 * 0.6x
you got it from here?
wait it says that x is days tho
sorry, this is a different x
i was being confusing
it's 0.6 * 0.6 * 0.6 * b
and you want b
so we let b be the original amount
wait would it be y=b times 0.6 ^x
and then we can plug in at 3 days
wait but where would we plug in 0.6
To find b
i think it would be y = b * 0.6^(x / 3)
yeah it is that like x/3
But indont understand it
And also how do we plug in the value for y
wdym?
like, you don't understand how it works?
wait never mind
I use the second question
I don't understand why its x/3
why can't it just be x as that denotes the day
Result:
0.216
but you see, after 3 days it's not supposed to be 0.216b, it's supposed to be 0.6b
of course, you could also do it by using a different value instead of 0.6
sure
^
so y = a * b^t right
ye
it's currently 35,000 so a = 35,000
oh wait so in an exponential is the value of a is original amount all the time
now, if it doubles every 4.2 years we can do an approach similar to the last question
ahh that would make sense cause ur timing it
yes
at least in the form used there
👍
y = a * 2^(years / 4.2)
oh true
oh so it would be y=35000 * 2 ^years/4.2
and then we plug in 12years to find the b
yes
Ok thanks so much
I have a test
I'm like 30 minutes its about parabola and non linear
I hope I get good mark
🙏
no imnnot
haha
I just wanted to touch on that question because inwasny confident
.cloae
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hi
can someone please help me w calculus ab
question 10 here
it doesnt come w a graph or anything i dont rlly get it
cuz if i factor it i get x+3 but it says what is wrong
well i can plug in x = 2 on the right side, but on the left side it's undefined...
yeah the question is wrong
its for limits
the left hand side has a removeable discontinuity
oh, interesting
i get what they mean
sure so they're not equivalent
you see why, yea?
they still phrased it wrong
yea its phrased weird but i see what they mean now in context
@full plinth you get what they mean in the key?
yea
for questions like these (any one of them) i cant plug x in until i completely factor it?
usually you don't get so lucky
the easiest way to solve a limit is if the function is just defined at the limiting value
so if it is, you can
they don't usually give people problems like this, other than to demonstrate that it's possible
oh ok thanks got it

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chat is this good so far i feel like i messed up
@pliant canopy Has your question been resolved?
Yeah me too buddy
Do that in another chat
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oh that's a factoid. Neat
Im not gonna get help am i😔
sorry I was looking at it and my game started. Give me a moment
Yeah that looks fine so far, you still have to undo your substitution to get your final answer though. But good use of trig sub 
@pliant canopy (ping if you were expecting one. Sorry if not 😅 )
Oh oki thanks
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Looking for statistics teacher immediately,even students with good command are welcome
you can try asking in #discussion or #study-discussion for that, but a help channel is not the right place to ask these i believe
it is indeed not the place, consider resources like khan academy too
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ok i NEED help with problems b and c (i have somewhat of a clue of what im doing but for the most part i need an explanation)
btw the second image is what me and my friends got from trying to understand this insanity
the graph shows the rate of people arriving at the ride yeah?
yes
don't call me "dude" please.
oh sry ms
thank you.
i didnt see 🫢
the line has newly arrived ppl going in at the back
and going out (and into the ride) at the front
the amount of ppl in the line changes only from these two factors
so the rate at which that happens is equal to the arrival rate minus the ride-seating rate
capisce?
ok
thx
so between t=2 and t=3 hours, are we getting more arrivals than we are seating, or less?
we're getting more arrivals, correct?
mhm
now how do you think we can find when the line for the ride is longest?
i just dont know tbh
ok let's try to call on some physical intuition
imagine you throw a ball in the air, vertically
what can you say about the ball at the instant when it's at the highest point in its trajectory?
ohhh
0
uhm
is that it?
Ya because when it’s far up in the air it stops for a second then comes back down
Yk what I mean
mhm
would've appreciated if you had let OP come to this himself
but anyway yes the instantaneous velocity at the peak of the trajectory is 0
you may know that in general, a function's derivative at a local min or max point is 0
so what we want, then, is to find when the new arrival rate is equal to 800 ppl/h
wouldn't that be at hour 3 or am i misunderstood?
yeah that would be specifically at t=3.
@spring maple Has your question been resolved?
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is there any good ways to prove the recursive sequence x_n = 0.5(x_n-1+1/x_n-1) is bounded?
or it has an upper bound
it has a lower bound 1, i've calculated by using basic inequality
What is x_0?
1
then sequence is constant?
hmm?
Oh now I see the +
yea it's constant apparently
you might prove that
by induction
x_n = 0.5(x_n-1+2/x_n-1)
,w x=0.5(x+2/x)
we can prove it is bounded for any t by monotonicity of the recursion function
let f(n) = 1/2(n+1/n)
then $x_n = f(x_{n-1})$
AlmondAxis987
now if $x_0 > 0$, then $f(x_0)=x_1>0$
AlmondAxis987
inductively, all $x_n > 0$
AlmondAxis987
how about upper bound
now for $n>=1, f(n) = \frac12(n+\frac1{n}) <= \frac{n+n}2 = n$
cool
AlmondAxis987
because $n>=1 \implies \frac1{n} <= n$
AlmondAxis987
but $x_n \geq 1$for any n
AlmondAxis987
damm
lol pls I cant tell if ur saying Im wrong or im right 😭
Did you replace x_n with n, and also wasn't it 2/x_(n-1)?
ig OP will close it when he finishes
