#help-17
1 messages · Page 64 of 1
Okay
But ima do it my own
I am going to interrupt quickly here
Iw ont botheryou anym9re
let me show my final work
First we state a few theorems we will use
if lim n->infinity |x_n-L| ->0 then x_n->L
if a_n -> a then sqrt(a_n) -> sqrt(a)
also, {1/k} -> 0
the epsilon n proof is easy for that
let k>1/epsilon
?
$\lim( |x_n - L|) = 0$ , then $x_n \to L$
Bishop
????????????
Oh
Interesting
I never thought of it that way
Neither did i ever see that theorem ever
lim xn -> x if and only if lim |xn-x|=0
anyways
using those theorems
this is |x_k-L|
by the theorem about sqrt(a_n)->sqrt(a) and 1/k -> 0
we get that the numerator -> sqrt(2)
using just that 1/k->0
we get that the denominator -> 2
using the theorem about if a_n -> a and b_n -> b and b!=0 then a_n/b_n -> a/b
we get here that the left hand fraction (x_k) goes to sqrt(2)/2
so the limit of |x_k-L| is sqrt(2)/2-sqrt(2)/2 is 0
so we get that x_k -> L=sqrt(2)/2
that seems valid to me
Works
though of course if you do it the algebra of limits way you can cut down a bit
awsum
From there you'd be fine 
ok cool ty chartbit
sorry it took me so long
I was trying to choose a k for too long
finally gave up on that
Mind you, if you did choose the epsilon-N way, then provided you could show this that way
You could manipulate the upper bound to be that and you're happy 
yes let k>1/eps
hmmm
"making denom smaller" and all 
Either way algebra of limits is much nicer to do these with honestly, saves so much time
(it also isn't too bad to prove the algebra of limits either
)
mhm
@thin vale Has your question been resolved?
you got your name back
yes I got an i earlier
I am working on this now
I am fairly confident I have the (=> ) direction
but I get stuck working in the (<= ) direction
We let ${x_k}$ be a sequence of points of $S\setminus {\vec{a}}$ s.t ${x_k}\to \vec{a}$ and we want to show that this implies that $\vec{a}$ is an accumulation point of $S$
Austin
${x_k}\to \vec{a}$ tells us for all $\varepsilon >0$ we can choose a $k\in \mathbb{N}$ s.t $$|x_k-\vec{a}|<\varepsilon$$
Austin
which means that no matter how small we shrink the radius of our ball around a, (in S\{a}) there are still infinitely many x_k around a?
and x_k are in S so?
yes, the tail of the sequence is any epsilon ball
I am having trouble putting this into words for Rn spaces Bungo
you have to be somewhat cautious though, as the elements of the sequence aren't necessarily distinct from each other (so if you knew nothing else, the sequence might only assume finitely many values, and then your argument doesn't work)
so you have to use that none of them are a, yet the sequence converges to a
if none of them are a, then the sequence can't be a constant sequence b, because that would converge to b, but b not equal to a
so the sequence is not a constant sequence
so the elements are distinct
they don't have to all be distinct
just rule out the possibility that there are only finitely many values
can I ask you a different question actually Bungo
sure
I think it'd be better I sort out my confusions with the other part first
because I have the idea but I have trouble making arguments with balls
so
let $\vec{a}$ be an accumulation point of $S\subset \mathbb{R}^{n}$
Austin
then $\forall \varepsilon >0$ the set of $\vec{x}$ within a ball of radius $\varepsilon$ of $\vec{a}$ interesected with $S$ disjoint $\vec{a}$ is nonempty
Austin
yep, not only nonempty but infinite
${|\vec{x}-\vec{a}|<\varepsilon} \cap S\setminus {\vec{a}}\neq \emptyset$
Austin
I can write this statement for all epsilon>0 correct?
and like you said it is also infinite
yes
$${|\vec{x}-\vec{a}|<1} \cap S\setminus {\vec{a}}\neq \emptyset$$
$${|\vec{x}-\vec{a}|<\frac{1}{2}} \cap S\setminus {\vec{a}}\neq \emptyset$$
$${|\vec{x}-\vec{a}|<\frac{1}{3}} \cap S\setminus {\vec{a}}\neq \emptyset$$
Continuing in this fashion
$${|\vec{x}-\vec{a}|<\frac{1}{n}} \cap S\setminus {\vec{a}}\neq \emptyset$$
sure
lost my brackets there
Austin
so this tells us that there exists $\vec{x_1},\vec{x_2},\vec{x_3}\dots \vec{x_n}\in S\setminus {a}$
Austin
that are within any arbitrarily small radius of $\vec{a}$
Austin
sure, you can pick x1 in the first set, x2 in the second set, x3 in the third, etc
yeah
notice that you need the axiom of countable choice for this
I lose my mind right here
yes, that construction is fine
I can no longer formally state what I am trying to say
after that point
It frustrates me
you don't need to say "arbitrarily small radius", you can say:
the distance between x_n and a is less than 1/n
(and greater than 0)
so for each n you have the inequality
0 < |x_n - a| < 1/n
The other direction is very easy. It’s just that suppose not, you have a r, such that the neighbor of a, a ball radius r, center at a, contains finitely many x_k: k from J, then those distance(x_j,a) >r for any j that isn’t in J, so for all great enough j, distance(x_j,a)>r. Then x_j impossible to converge to a, contradiction
then |x_n - a| is sandwiched between 0 and 1/n, both of which go to 0 as n goes to infinity
hence |x_n - a| must go to 0
and hence...
x_n -> a
yep
and all of the x_n are not equal to a
correct
indeed
Okay ty bungo I appreciate that
Idk if you have ever related to that kind of feeling but gosh it is just like everything I just studied in R being taken to Rn and I have the ideas but I just completely suck at trying to say them
yea, things can get a bit confusing every time you generalize a bit
but you won't lose a ton of intuition if you consider that balls in R^n are just intervals in R
with intervals this is so easy
the main thing that breaks down in R^n but works in R is that in R^n, you can't necessarily express every open set as a countable union of disjoint open balls
whereas in R you can
but that doesn't affect you here
this is for in R... I had no trouble with it whatsoever
cluster point = accumulation point
yea, to translate this sort of argument from R to R^n it's helpful to translate things of the form
x - epsilon < x_n < x + epsilon
to
-epsilon < x_n - x < epsilon
to
|x_n - x| < epsilon
all of which are equivalent in R, but only the last one can be used in R^n
so now I want to translate the (<= ) argument into Rn
which started by supposing the existence of a sequence xn in S disjoint a that converges to a
and from this we have to show a is an accumulation point
right
since the definition of the sequence converging gives for all eps>0 |xn-a|<eps we can form a ball around a of radius epsilon which contains elements of the sequence xn?
for any radius we'd like
elements of xn are in S yet not equal to a
right
hmmm
so
any ball around a
of any size
contains elements of S disjoint a
these elements being the xn in our sequence
but how do we know there are infinitely many?
suppose for contradiction that there are only finitely many
so the sequence xn assumes only finitely many values
that means there exists a subsequence which is constant
yes
and not equal to a
right
that subsequence converges to a
which isn't possible
Okay so let me restate
Because we have a sequence of elements of S disjoint a that converges to a, from the definition of sequence convergence we get that for all balls centered around a of radius epsilon,
|x_n-a|<epsilon
That is, any ball around a contains elements of our sequence, which are elements of S disjoint a.
Suppose that our sequence contains finitely many elements, then there must exist a constant subsequence that converges to a. But, for a constant sequence to converge to a value it must take on that value. But, this subsequence of our original sequence cannot take on a, and thus cannot converge to a. This contradicts the existence of a constant subsequence converging to a, which contradicts our sequence containing finitely many elements.
Is this proper?
"from the definition of sequence convergence we get that for all balls centered around a of radius epsilon,
|x_n-a|<epsilon"
This part holds for all n past some N, not necessarily for all n
(where the N depends on epsilon)
the rest looks ok
nope, just mentioning it for completeness
I have one final piece of confusion about what I just said
any ball contains elements of our sequence yes
and our sequence doesn't have finitely many elements yes
but how do we know that a certain ball doesn't have finitely many elements from our sequence?
because all terms of the sequence must be in that ball, for n >= N
i.e. the tail of the sequence must be in the ball
if the tail only takes on finitely many values then so does the entire sequence
why are you guys so smart
Bungo is the only smart one here
since the whole sequence is the first part (with finitely many n) followed by the tail
idek what u guys are talking abt
not smart, just more experienced with this material
btw lmk if u guys wanna help me solve a probability dice problem whenver u guys have time:D
HAHAHAH
is it this one? #help-3
i can take a look, if austin is all set now
Let me have 30 more seconds to confirm that
sure
yes
oke tysm<3
I am all set
cool
thank you very much Bungo
yw
you're great
cheers
seriously
cya!
Since the closure of S is defined to be the S union Boundary of S
I need to show that boundary of S equals the set of accumulation points?
that is, the accumulation points are a subset of the boundary points,
and the boundary points are a subset of the accumulation points?
Is that true or am I missing something here
no, an accumulation point need not be on the boundary, and a point can be in the boundary without being an accumulation point
example 1: in R, let S = (0,1), then 1/2 is an accumulation point not on the boundary
example 2: in R, let S = {0}, then 0 is on the boundary but not an accumulation point
what you need to show is that if you have a point in the boundary of S that is not in S itself, then that point is an accumulation point... that gives you the containment closure(S) ⊆ (S U accumulation points of S)
then you need to show the reverse containment too
@thin vale Has your question been resolved?
Okay TY Bungo I will work on that
@thin vale Has your question been resolved?
@thin vale Has your question been resolved?
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Im having a problem on my exam review. You’re supposed to solve a multi step question, which i have, but then I have to check it and it always stumps me. The first photo is an example of what the checking looks like (done by my friend) and the other picture is my work and what it looks like. I would like someone to guide me, i would appreciate it very much
how do i check my answer?
Just plug in the value you got into the equation
So you got x = -1, plug that into the equation
okay got it hold on
What's -6 * -1
it’s just 6
oh wait
thank you so much im like rlly slow with math i need like a guide when i do it sometimes but thank you
That's all you do to check your answer, you just plug it back in
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another question. gave this distance question a shot and i’m still so confused. i need some help
Draw a right triangle connecting the points
Where the hypotenuse of the triangle is the straight line shortest distance between the two points
And then use Pythagorean theorem to solve for the length
well it’s distance like the distance formula i was taught this way to do it
but that was with my teacher
The distance formula comes from the method I described
oh
It’s asking me to identify the function family to which f belongs but how am I supposed to identify that?
This channel is occupied
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okay so would it look like this? sorry it’s hard to read
Yes like that
okay okay i’m gonna use the pythagorean theorem formula real quick
so the distance is 5?
Yes
thank you sm!
Do you see how that is the same as the distance formula
yeah i think so
Great
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How do I use desmos to graph vector functions
like how would i graph this situation?
desmos can graph the parametrization of the vector valued function
so if you are able to find the position vector
it can graph this
but the accerlation vector is constant, there is really no function to graph in that case
@vast shale Has your question been resolved?
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can someone help with the last two questions of part b? part a answer is 1/2
Write it out on a paper
It’s nothing more than taking your answer from a and solving for cos(x) step-by-step
i’m setting 1-cosx equal to 1/2?
sin^2x/x^2 multiplied by 1/1+cosx
No no, skip to the end
CST
yea
so 1 - cosx = 1/2?
Where did the x^2 go?
in part b the question is 1 - cosx
What’s your answer to box 1 of part b?
1/2
there’s no x^2
multiply by x^2??
multiply by x^2
1/2x^2
please use parentheses so that it’s clear
(1/2)(x^2)
CST
Isolate cos(x) now
1 - (1/2)x^2
no
Where are you confused, the transition from box 1 to 2 or box 2 to 3?
2 to 3
Ok, let’s walk through this
wait i get it ty
Nice, no problem!
.close
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hey is anyone good at fraction
i need help i forgot it
Send the q
"good at fraction" means nothing by the way
@craggy acorn Has your question been resolved?
The first 1 is rewrite fractions into mixed numbers the 2 is rewrite to a spurious one and the 3 is reduce as much as possible, submit as a real fraction or mixed number
im bad at math
<@&286206848099549185>
what question
your elementary school?
Lmao
bro thats kinda easy
Kinda?
yes, why?
It's too ez
...
BRO GOT DAMMIT, i will teach you
Thx
opgave 3 right?
dont make me to a asian mom
i need to finnish it now and send it to my teacher
jsut 1 question then
number 2 and
this one
imma just not do opgave 3
ok
How old are you?
Because Discord is for people with age ≥ 13
14
💀 🐒
shut up
Ok no prob then 👍
hell nah
😭
Pretend to be a couple then
maybe i wanna die, i will chat you soon, cuz i wanna turn off this laptop and wanna go to the summer
i already add you
@visual drift @burnt temple this is not the place.
@craggy acorn is there anythin you still need help with?
@craggy acorn Has your question been resolved?
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what does complex exponentiation actually mean
ho do you multiply a number by itself i times
you dont
you take a function exp(x) which for real numbers corresponds to repeated multiplication, and then extend that function to complex numbers
I always thought it's more intuitive to think of multiplication as operations on a vector rather than the repeated addition idea schools give you
The idea itself breaks apart for negative numbers
even something like x^0.5 challenges the idea of repeated multiplication. you can kind of imagine multiplying a number half times but it doesnt really work
That's not the point
then hat is
do you really think of x^0.5 as repeated multiplication or do you think of it as something else
whatever that something else might be
well
it is repreated
but you cant repeat half
so we multiply half the amount of times we normally do
it's kinda the same thing we've done to multiplication to extend it from natural numbers to real numbers
like, if you view 4 * 3 as adding 3 copies of 4
something like 3.2 * 5 doesn't make sense, so we extend the definition in a way that is back-compatible with our previous notion
and note that it really is a definition at that point
the taylor series of e^x is a theorem
but the extension of e^x for complex x, or other inputs, by means of plugging them into this series can be taken to be a definition
so its just undefined?
the question "how do you multiply a number by itself i times" is undefined
because that's not what we mean by exponentiating by a complex or imaginary number
we can extend e^x to complex x
so we just combine it with (complex) logarithms
and we can transform the e base to any number, like 2
or more simply, write 2 in polar form and combine it with i
another perspective: if we step really far back, multiplication is repeated addition. so if x^0.5 is multiplying by itself half times, then it is also in some sense repeated addition. but by this point you really have to see that this is not any useful way to view what is going on
somewhere along the line we stop viewing multiplication as repeated addition and see it as its own thing
and this is also now happening with exponentiation
@boreal path Has your question been resolved?
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BrotmitHonig
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write an x insteadof 38 and solve it for x
It does not say whether interest is compund or simple
So I guess, too - can you be sure?
!show
Show your work, and if possible, explain where you are stuck.
I think bot give a good idea. Show? Meanwhile, I shall solve it myself and then explain
ok
Where is your formular from? The way I read your problem - it's just like this - GCSE level
that is wrong, you missed the 800 are paid every xear
If you are 15 years old - you find n by trial and error, if you are 17-18 year old level - use log
You are right
Wait
i guess the -800 at the start are wrong. but anyway. from the last line multiply by 1,025-1 then add 1 then use log
if youe aplly log at the right side - what do you get?
@cursive turret - I'll leave it to you - I overlooked... yes You are on track
Good luck !
lets discuss this leter, now for log. ok apply log to the left side?
$log(a^b)=b \cdot log (a)$
ThM
x times log (1.025) = log (16.556)
divide by log 1.o25 and you have x
i guess you made the "multiply by 1.025-1" part wrong, this gave me some smaller then 16
yes
something like that
and the -800 is right, as you need the value at the end of the year
lets start with the last year. 800 at the start of the year you need the value at the end -> 800 times 1.025
for the year before: 800 times 1.025 ^2 and so on.
so yo have the sum of 800 tines 1.025 ^i with i from 1 to n.
no. wait a moment. you have now $\sum_{i=1}^{n} (800 \cdot 1.025^i)$
ThM
this can be written as $800 \cdot \sum_{i=1}^n 1.025^i$
ThM
and now look at the sum this is the geometric sum, where a formula exists.
but this formula starts with i = 0
$\sum_{i=1}^n 1.025^i=(\sum_{i=0}^n 1.025^i)-1$
ThM
just wait.
$800 \cdot \sum_{i=1}^n 1.025^i=800 \cdot ((\sum_{i=0}^n 1.025^i)-1) = 800 \cdot(\frac {1.025^{n+1}-1}{1.025-1}-1)=800 \cdot(\frac {1.025^{n+1}-1}{1.025-1})-800$
ThM
where your solution 38 means n+1
$800 \cdot \sum_{i=1}^n 1.025^i=800 \cdot ((\sum_{i=0}^n 1.025^i)-1)$ is this clear?
ThM
$800 \cdot ((\sum_{i=0}^n 1.025^i)-1) = 800 \cdot(\frac {1.025^{n+1}-1}{1.025-1}-1)$ is this clear?
ThM
i did not change the -1 it is on the left side in the bracket, it is on the right side in the bracket. i only replaced the sum by the geometric formula. look at https://mathworld.wolfram.com/GeometricSeries.html for the S_N-Formula, if the sum goes from 0 to n the exponent in the fraction is n+1
A geometric series sum_(k)a_k is a series for which the ratio of each two consecutive terms a_(k+1)/a_k is a constant function of the summation index k. The more general case of the ratio a rational function of the summation index k produces a series called a hypergeometric series. For the simplest case of the ratio a_(k+1)/a_k=r equal to a cons...
because i didnt evalute the brackets at this moment, this is the last step.
$800 \cdot(\frac {1.025^{n+1}-1}{1.025-1}-1)=800 \cdot(\frac {1.025^{n+1}-1}{1.025-1})-800$
ThM
we started with this. which gave as a sum from 1 to n. where n is the number of year.s. then we added the i = 0 term and subtracted him again (the minus 1 part), we got a formula with n+1 which we solved and got 38. so n+1 = 38 -> so the answer is 37 years.
just drop the -800 is a wrong solution. there is a way without the -800 part, but then the term to solve is a little bit different. a different way, which gave you the same (!) solution, not only in a rounded way.
if you are interested we can do this other way
lets start with the same sum: $800 \cdot \sum_{i=1}^n 1.025^i$
ThM
ThM
ThM
you said ok to this.
ok
lets look on this
$\sum_{i=1}^n 1.025^{i}=\sum_{i=1}^n 1.025 \cdot 1.025^{i-1}$
ThM
and now take the 1.025 before the sum
we want a sum starting from 0 to use the formula for the geometric series.
$800 \cdot(\frac {1.025^{n+1}-1}{1.025-1})-800 = 48980$
ThM
that is the starting point.
add 800
we did this step by step, and this was the last step: #help-17 message
if it is needed we can start from the beginning again.
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hey guys I think the solution I am given is wrong but I need to reassure myself so I'd really appreciate someone helping me out by confirming that this is wrong or otherwise tell me that I'm dumb
so I have the integer set 1 through 8 and B:={at most 7} and C :={all odd numbers}
Now the book says that BuC would be {1,3,5,7} but I believe it should definitely be [7] so B, right ?
Yeah it should be {1,2,...,7}
It looks like they calculated intersection instead of union
which would be (B \cap C)
fréchet_filter
@forest crater Has your question been resolved?
What is your neuromanifold.
stop trolling
alright, thank you very much!!
.close
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i keep getting stuck trying to find limits. Am I supposed to just plug in 1.000001 as values and take that answer? Or am I factoring wrongly?
x^2 + x - 2 does not equal (x+2)(x-1)
Why?
Aye aye 😂😂
What does a factor in the denominator imply about rational functions
If it doesn't cancel out
not sure?
Think about the function 1/x
Well it Doesn't not exist
so theres an asymptote at 0
yeah
Yeah
how does it help me
U can draw a rough graph with it
now think about where the vertical asymptote is if the factors in the denominator are (x-1)(x+2)
-2 and 1
approaches 1?
Does not exist
huh
Think about 1/x again
so you're saying the limit doesn't exist
Yep
when it approaches from up to down
The left and right sided limits give different answers
this is right sided
it doesnt say so in the question
So the limit has to be infinity then
brother are u sure about this
Check it by plugging in values close to but greater than 1
so 1.000001 etc which i stated initially
Ooo this is a new notation to me
yeah or 1.1 or 1.01
I have never seen that either
Yeah we use 1^+ for RHL and 1^- for LHL
x -> 1 like this
same
So it's quite interesting
okay so the answer was infinity
What does the down arrow means
right limit
Oo then it is +∞
how can u see that
i can't understand why
when i plug in values close to but greater than 1 i get -5.5
for my factored equation at least
Is u put 1 in (x-7)(x-5) u get positive ryt
The x+2 for 1 is +ve
So just x-1 is left
Now if u approach it from right side which means a little greater than 1
Therefore x-1 for x= something a little greater than 1 should be positive
so you think of it as positive values divided by a veeeery small but positive value. So naturally it must be a v high answer
Yeah
because (x+2)(x-1) must be v small
Yeah
and for negative infinity, it would be opposite, so it would be a veeeery small but negative number
division by that
Yes
U put 1
When if it is 0/0 u gotta do work
If it is 0/something finite then it should be 0
It doesn't matter if it is +ve or -ve since it is very close to 0
for these types of problems, should we always test initially with a lim value or the actual value
plug in 1 or 1.00001 so to speak
Just do 1
YES
Always be on look out for indeterminate forms
you should work out the left and right hand limits
The question is RHL
Tho
IF IT IS NOT A FINITE #
If it is not mentioned then check both sides
Im seeing a 1 not 1^+
ok so i plug in the value. Now I can get many different types of results. What should I look out for? 0/0 means more work
oh so its mentioned?
the downarrow is notation for right hand limit
Yeah I was confused too the down arrow supposed to represent 1^+
oh new concept for me
Me too
yeah, ^+ and ^- is definitely more usual
when i plug in values, 0/0 case means more work. 0/finite means 0, what other cases are there
in this its gon be +INFINITY
Yeah 0/0 ,∞/∞,0⁰ , etc
1^∞
0*infinity
∞⁰
1^infinity
Oops my bad
Which one
Nice
yeah
these means indeterminate forms which are a non defined result
oh okay so i was only working with fraction limits so far
means more work
so i see these are other forms
might be simplifications
you might not have taken them yet but you will soon regarding limits
Why?
wow, this feels like a lot to remember
not really
Nah bro just practice
and these indeterminate forms
we can determine already from its initial form? before any simplifying?
cannot
U need to do more work if u see these
you mean determine if its indeterminate then yes
yes
i mean to determine if its indeterminate
so we dont need to first simplify to see what type of limit it is
No just plug the value in the function
yeah you should first in limits plug the value to see if its a number then we dont need any simplification
indeterminate forms need
okay good
so first plug in values. Determine form. Then try to simplify. After simplifying, i understood for fractions, if the denominator is infinitely positively small it is positive infinite limit, if infinitely negatively small it is negative infinite limit
yes but
watch the numerator too
The small factor might even cancel out
its sign might be negative or there is cancelling out process
if the small factor cancels out, then it is ... 1 ?
or negative 1?
or i guess it depends ?
it depends
i'm still confused as to know when a simplification is really "finished" (if i did it right in the first place), and then what to do, and then how to analyze the results of what i did
for the "what to do" step, is it just simply to plug in values again?
plug -> the result is a finite number? you are done, the result is an indeterminate form? do some work.
Maybe explaining with an example question might help
from marty?
i can get another one
Yeah
This ones not indeterminate...
yes
let em try it
okay great hold on
i tried getting an indeterminate one for 2 min all were determinate -_-
lemme look at yours
-2^+ is just the downward arrow to -2
3/0, meaning indeterminate ?
My bad
I messed up bad lol
0/0 indeterminate
yeah
Bro I was trying to find one all the questions I have have log or a trigo function
i got plenty of poly
All the poly I have u need to take log both sides 💀
1^inf situation
Yeah 0^0 and ∞^0 too
We were forbidden to use L'Hospital by our teacher 🥲
Nice
me too at first but then he allowed it when we took the rule
check this one
yeah true
As long as it's not log 0 somewhere we don't use L'Hospital
i only got 0/0
surely here you would use a different method, because plugging in q gives weird eq
just a simplification
Its 9 not q
😂
that makes sense
i didnt realize lol
Can u give me some tough ones it's been a while I did limits
allowing lhospital?
I have been doing indefinite Integration for quite a while
Hmm u can give any
i have done the course of integration, was greatttt
Yeah it's good
,rotate
like taylor series
Yeah
yeah
It always works if L hospital is to hard to apply
U need to factorise first
ok
yeah
U can take cos(sinx) + cosx out of lim
why?
U could have dmed
sorry
@long flame u here?
yeah
It's ok
i was working on the sqrt lim
U tried the limit?
marty
which still gives zero
isnt it sqrt(x)+3
oh yeah
no
$(x+9)*(sqrt(x)+3)$
Sherlock
108
my man
Correct
cool
U understand it now ryt
well the steps are getting clearer
here i felt confident the simplification was done because i was no longer dividing by zero
and i was always trying to cancel that term
Nice
and finite division by zero is still workable right
yeah its DNE
Don't exist
specifically +- infinity
Yeah
i mean for the initial stage before simplification
oh
unless its an indeterminate form
okay so it is determined, and its either + or - infinity
yeah
Save this
determinate but it is zero
like 0/2 ?
yessir
no worries bro
No problem
any question just send a mention
i will close for now 😄 🙏
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how is this undefined at f(4). It is 0 over 1 which is 0, not undefined
denominator becomes 1/4 - 1/4
omg
too quick sorry
i was thinking it was adding for some reason
now makes sense
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Trying to spot where they are haha
Is it like this?
The one on the right is obvious but I wasnt so sure about the one on the left
I wouldve guessed there was only one point of inflection if they didnt tell me
Yeah it's quite hard to see but I would agree
Okok nice
Points of inflection are kinda new to me so I just wanted to be sure haha
Thank you! Thats all I Wanted to ask
❤️
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how did i do?
@glacial meadow Has your question been resolved?
@glacial meadow Has your question been resolved?
@glacial meadow Has your question been resolved?
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Why might it be useful to convert radians to degrees?
a radian is the angle where the arclength of a circle is equal to its radius
In this video, we explore the concept of radians and why they are a useful unit for measuring angles. We start with an introduction of degrees, explaining the way we're all used to measuring angles. Then, we dive into the mathematical properties of radians, including the relationship between the circumference of a circle and its radius. We also ...
ohhkay
Because radians are unitless, since they arise from ratio of lengths
so like indefinable?
And unitless quantities mean numbers which we can put inside functions
No no, indeed you have been given the definition of radians above
Unitless means that there's no unit, it's not in meters, neither in kilometres, nor in seconds, nor in kilograms and so on
Simply it is a number, hence a quantity with no unit
@timid leaf Has your question been resolved?
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Hello
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Please post your question
For the first value of a i think it’s either a horizontal stretch
But the amplitude is different also
<@&286206848099549185>
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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'm told it's wrong
4. I got an answer and would like my work checked
5. I have a question about someone else's worked solution
6. None of the above
4
Show your work, and if possible, explain where you are stuck.
cool, can you show what you did?
SOrry i mean 1
I don't kknow where to begin
is it simultaneous equations?
wait nvm
someone else gonna hel me
thansk
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i didn't feel satisified in this simplification, is it rly enough to leave it like this? I just started using trig. addition rule
it could be simplified a little bit by adding the fractions together.
oh yeah fair enough
you could also factor out sqrt(2), but i'm not sure that it's "simpler" after that
$\frac{sqrt(2)+sqrt(3)*sqrt(2)}{4}$
marty
yeah but also sqrt(3)*sqrt(2)=sqrt(6)
wait
so you could have $\frac{\sqrt(2)+\sqrt(6)}{4}$
Wumbo
i forgot apparently how sqrt works. so sqrt(x) * sqrt(y) = sqrt(x*y)
yep!
not really no
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cos120 is the same as -cos30 right?
No
Odd question
F Discord
-sin x
i was thinking in terms of the unit circle
Even then
that we've gone past 90, and now we're in negative space for cos, and then 30
how about, cos120 = -cos60?
that should be correct right?
ah wait mb, yes looks good
how do u do the wolfram query
,w (query here)