#help-23
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You need to find c where the point (c, 0) is in L
When you apply the equation to (c, 0)
You got : 0 = -c +10
so c=10
dw
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P is a power set here
do you know the definition of injective
also what is the function
every element in one set can be mapped onto a unique element of the other set
sorry my goal is to construct a function that is injective onto T

or like
oh i guess binary encoding might work
any uncountable set would work. All I need to do is to find a function f that is an injection from P(S) onto an uncountable set
so I can show that P(S) is uncountable
does this make sense? @plucky elk
maybe? hard to judge without an actual funciton
well how would you prove that P(S) is uncountable?
if I can prove this I basically solved my whole assignment
power set of any countably infinite set is uncountable
okay so this is a proof to why P(N) is uncounable
S is bijective onto N (I already proved it). so can we imply from that fact that P(S) is also uncountable?
@plucky elk
yes
and if an uncountable set is a subset of another set, then this set is also uncountable right?
@lean otter Has your question been resolved?
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Can anyone give a pair of x,y,z that show that this is not a linear transformation?
Every pair I have tried pass by both scalar multiplication and matrix addition. I dont understand how this can not be a linear transformation
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@silk flicker Has your question been resolved?
@silk flicker Has your question been resolved?
Just test (0,0) and if it moves it’s not linear
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why is arctan(1) = pi/4?
i am confused on how to solve for this answer
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$b^{\frac12} \cdot{b^{\frac45}}$
Springsskateboard
oh nevermind 💀 i thought those were full fractions
yeah
take the reciprocal
and exponent becomes positive
yep
nice
ggwp
mhm
in ur mom’s house
tell me where you live NOW @lusty widget
Ayee sounds good
yeah..all over the news :(
honestly, i doubt anything can beat what they have in india
didn’t study in Korea’s curriculum
bro India built diff
respect to them
you are going to fight Cthulhu
I’m going to fight the belt
If I catch the belt then I’ll get a slipper thrown at my face
oh damn
calculus isn't thaaaaaat bad
calculus is love
until you get to integrals, then things kinda get harder
except for when it’s not
exactly
let me quote what my very insightful teacher said
“>50% of students fail this class”
fking hell
I found out he was lying
Everyone passed
HAHAHHA
here we don’t have calculus as a separate class
it’s all combined into one subject
math ✨
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from my end
to quote my inspirational electromagnetism teacher, "you are screwed"
you too my bro
HAHAHAH FUCK
I dropped physics 😎
based
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Hopped on to the good ol biology/ chemistry side
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okay nvm u went to worse
HAHAHAH FK OFF
😵💫
bio>phy
tbh by this point...maybe
Wrong
yes, I’m shedding light on the truth

🙌
YAS
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Need help with some math. Lol. I want to trade in a phone with T-Mobile. T-Mobile has two promotions. Trade-ins are worth either 1000 or 800 credit depending on model.
I want to purchase a used phone for 100-300 and trade that one in for credit towards the iPhone 14 pro max (1100). Can someone help write this equation out? I have an excel spreadsheet that gives me an idea. For my budget, phones worth 1000 credit I shouldn't spend more than 300. For phones worth 800, I shouldn't spend more than 100 (maximum I can stomach coming out of pocket is 400)
(cost of iPhone 14 pro max) minus- (trade-in value of used phone) plus+ (cost of purchasing trade phone) plus+ (whatever owed/remainder to get to 1100) = (total out of pocket cost)
(1100-800=300)+X==Y
(1100-1000=100)+X==Y
X is the variability in used phone prices. I figure "Y" is my budget. Is there some sort of equation or desmos graph that will tell me at what price point the deals come out even?
Please don't occupy multiple help channels.
Wait, so you essentially want to buy a used phone for the purposes of trading it into t-mobile to make a profit?
this feels...sketchy 
and unrealistic
Yeah I am not sure how something like guarantee, warranty, etc. is going to be considered here
if they are not, then i am not sure who is buying this..
Yeah I just think t-mobile is gonna offer a pretty low amount for most phones, I don't really see this being a net gain
but @white jay I'm not really sure I understand your question anyway
If you don't want to spend more than 400, then you need the used phone to cover 700. Which means you need to buy it for 700 less than what t-mobile will offer you for it
Profit implies I'm making money; I'm not. I need a new phone and want to get the best value and savings I can.
Well, what I mean is, essentially you need to have a net gain of 700 from when you buy the phone to when you sell it to t-mobile
Right. So you want to buy a phone for $100 and sell it to T-mobile for $800
for example
That's what I meant by profit. Obviously when you buy a new phone at the same time, you're gonna walk away with less money
Yes. However. The 14 costs 1100. If I spent less than 300 purchasing a used phone to trade, that would be a better deal than the 800 credit offer.
How did you get 700?
In both your examples, the difference between "trade-in cost" and "trade-in credit" is 700
800-100=700
and
1000-300=700
I don't understand your "difference" column
Ahh. I see. The 100/300 are arbitrarily put there bc my max budget is 400. Online prices are all over the place and the 100/300 should be variable
Oh yeah ok
Difference column is difference between trade credit and price of iphone 14 pro max
Ok
Yeah bottom line is if you want to pay 400 instead of 1100, then you need to profit 700 buying and selling the used phone
400+700=1100
Basically just that
It would be neat to see a desmos graph with an x slider that plugged into both equations (trade credit offers)
I'm sorry, I'm not sure what you mean. Here x represents what?
The variable cost of purchasing a used phone to trade in.
And the outputs of the functions would be?
How much you need to be able to sell it for?
It's not really a complicated function, if I understand correctly.
You need to buy the phone for x and trade it in for x+700
You lost me there. I suppose the question is: with a max budget of 400, what method could I use to quickly determine which is offer is the better deal? Keep in mind: later models trade-in for 1000 credit, but cost more; older models cost less but only trade for 800 credit
Oh, the 1000 and 800 are known for sure?
My best equation for this is to know exactly my budget, and use excel to quickly tell me total out of pocket cost
Yes. With qualifying models of phones
For example: the iphone XR lowest price I've seen is 100, but only trades for 800 credit. An iphone 11 pro trades for 1000, but if I spend 300 purchasing it, I break even with the other deal. The deals are effectively the same after all is said and done with
Because I'm OOP 400
Gotcha
So if you buy the used phone for x dollars
If you buy an older ($800) phone, your OOP cost will be x+300
If you buy a newer ($1000) phone, your OOP cost will be x+100
That doesn't sound right
OOP = 1100 - (trade in value) + (what you paid for used phone)
If the trade in value is 800, that's 300 + x
If the trade in value is 1000, that's 100 + x
Older phone worth 800 trade in will cost me 300+X
Bingo
that's literally what I said lol
Beat me to it
I mean, it's the same thing you just said sounded wrong
The wording got me
Okay lol
Yeah, if you buy an older phone for x, your OOP is 300+x
And if you buy a newer phone for x, your OOP is 100+x
Is it really just that simple? Is there a graph that I can put a slider on X for both equations that would quickly tell me my OOP?
Yeah lol I'll make a desmos graph
But yes it is that simple
x-value is the price you pay for the used phone
Green y-value is your OOP if it's an older model.
Blue y-value is your OOP if it's a newer model
You can drag the points back and forth like a slider
@white jay
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Thanks!
No problem 👍
Good luck. I wouldn't have thought it's actually possible to buy phones that cheap to trade in
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If im tryin to find the equation of a secant line that passes through two points (a, b) and (c, d) is y - b = [(d - b)/(c - a)] (x - a) the valid formula?
where [(d-b)/(c-a)] is to find the slope
@crude star Has your question been resolved?
Determine a linear mathematical model for the temperature, T (in degrees Celsius), as a function of depth, z (in meters) by finding an equation of the secant line that goes between Nico’s two data points.
Is this right?
Or am I missing something
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dy/dx = x+y
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y’’ -4y’ +5y = 21e^(2x)
I got Yp = 21e^(2x)
Which is the same as f(x)
Is this possible?
Or have I made an oopsie somewhere in my solution?
,w y’’ -4y’ +5y = 21e^(2x)
Wow, very useful 👀
Your general solution is correct. Just a coincidence that y_p(x) = f(x).
Uh but wait
My general solution is e^x * (c1cosx + c2sinx)
The bot’s solution has e^(2x) instead?
That means I did the easy part wrong 
🙂
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hello, how can I solve this?
right so what's g in terms of kg
that's correct, but you still need to deal with the cm
how many cm in 1 meter
100
100 cm^3 = 1 m^3
the cubes are the same
volume of a cube is just side^3
so volume of the left cube is (100cm)^3 which is 1000000cm^3
and volume of the right cube is (1m)^3 which is 1m^3
so 1,000,000cm^3 = 1m^3
but how can that be, cubic just means that it's 3 dimensions
yeah exactly
it's volume
the volume of a cube with side length 100cm is not 100cm^3
it's 100^3 cm^3
I'm afraid I don't follow you
ok let me illustrate in 2 dimensions, might help you understand better
these 2 squares are the same
as 100cm = 1m
what's the area of each of them?
don't worry about tha rn
just tell me the area of left square, in terms of cm^2, and area of right square in terms of m^2
10 000cm^2
and the right square?
1m^2
Guys on day 0 you send a chain letter to 6 friends each of them sends it to 4 friends the next day and each of those people send it to 4 more friends the next day and so on i need recursive and explicit
right so since the squares are the same, the areas are the same
so 10 000 cm^2 = 1m^2
in other words ten thousand square centimeters makes 1 square meter
now do you see how the same logic applies to the cube?
square*
yeah ty
this channel is occupied, check out #❓how-to-get-help
yeah I see that now but how can I know this? is there some formula I can use to figure this out
what do you mean
you just convert the units
for example lets say we have km and m
1000m = km
and then cube / square
yes but I know that k stands for thousand. How can I know that 10 000 square cm equals 1 square meter
but it doesn't make sense to me since they are both using cubic
easiest way is probably just knowing the first one. so you have that $km=1000m$ then you square both sides to get $(km)^2=(1000m)^2=1 000 000 m^2$
Duh Hello
this is how it works
but lets say I had something else like 1 square meter to square mm
how can I calculate that
so you know that $m=1000mm$ right? then you have that $m^2=(1000mm)^2=1000000mm^2$
Duh Hello
oh so I can just square it
what if there is 4 dimensions?
okay
so for the start problem, you have $m=100cm$, how much is $m^3$ in $cm^3$?
Duh Hello
so to convert cm3 to m3 I have to divide by 10 000?
not quite, if it was cm^2 to m^2 then yes you would divide by 10 000
so now it's 1 000 000
since $m^2=(100cm)^2=10000cm^2$ but you have $m^3=(100cm)^3=?$
Duh Hello
exactly yes
this is what bo luo was illustrating here
would recommend looking at it and try to understand why
I couldn't understnad that
but I still can't grasp how I can go about solving this problem
its two cubes, one measured in cm and one measured in m
let me just repost it so you dont have to scroll
yeah I can see the cubes but I can't read the symbols
the one on the left shows that one side is 100cm, the one on the right shows that the side is 1m
but we know that 1m=100cm so they cubes are equal
yes I already knew that
so what is it that you dont understand about the picture?
Duh Hello
so the left one has volume $$V=l\cdot w\cdot h=100 cm\cdot 100 cm\cdot 100cm$$ and the one on the right has volume $$V=l\cdot w\cdot h=1m \cdot 1m\cdot 1m$$
Duh Hello
could you show your work?
there should not be a 2.5 in the denominator
2.5 / 1 000 000
you have that $kg=1000 g$ so $g =\frac{1}{1000}kg$, you then have that $$m^3=10^6cm^3$$ so you then have that $$cm^3=10^{-6}m^3$$you then have that$$2.5\frac{g}{cm^3}=2.5\frac{\frac{1}{1000}kg}{10^{-6}m^3}=2500\frac{kg}{m^3}$$
Duh Hello
didn't understand any of that
ok ill remove scientific notation
you have that $kg=1000 g$ so $g =\frac{1}{1000}kg$, you then have that $$m^3=1000000cm^3$$ so you then have that $$cm^3=\frac{1}{1000000}m^3$$you then have that$$2.5\frac{g}{cm^3}=2.5\frac{\frac{1}{1000}kg}{\frac{1}{1000000}m^3}=2500\frac{kg}{m^3}$$
I understand scientific notation
Duh Hello
but I have never seen the format you are using
i find an expression for $g$ and for $cm^3$ in terms of $kg$ and $m^3$ and then i just put them into the original expression which is $2.5\frac{g}{cm^3}$
Duh Hello
which is what you are doing when you convert units
what step did I get wrong?
well you only showed the answers both times and both were wrong so i dont know
you gotta show all the steps for me to see where you went wrong
well first I converted 2.5g to kg by dividing by 1000
then I did the same with the cm3 to m3
but dividing by 1000 000
and that got me the wrong answer
0.001
ok. what is 1 cm^3 in m^3?
I don't know how I can calculate that
well you know that $m^3=10^6cm^3$ right? what happens when you solve for $cm^3$?
Duh Hello
going to scientific notation since you said you understand it, then i dont have to count zeroes anymore
but you cant convert those, they arent something you convert
they are different dimensions
its like trying to convert seconds to meters
they arent the same measurement so you cant convert them
but look at this equation $$m^3=10^6cm^3$$
Duh Hello
what do you have to do to get $cm^3$ alone?
Duh Hello
no idea
well you divide by $10^6$
Duh Hello
this is just basic algebra
its the same as saying $y=3x$, what do you do to get $x$ alone?
Duh Hello
maths isnt just about remembering equations, its about using logic
well you don't know x so that isnt possible
$x=\frac{y}{3}$
Duh Hello
of course but it's important to know the formulas
thats solving for x
but you can use logic to know that
actually math is pretty much built on that, pemdas, distributive property etc
but anyways I just need to know the method for calculating this problem
maybe you can do cubic root to get rid of the exponent
Duh Hello
Duh Hello
okay I don't understand the logic of it
the logic is that you want $g$ in terms of $kg$ and $cm^3$ in terms of $m^3$ so you can substitute them into the equation $$2.5\frac{g}{cm^3}$$to get the right answer in $$\frac{kg}{m^3}$$
Duh Hello
but how do you get cm3 to m3?
this is what i am showing
where
here
where do you get the 1 and million from?
but to get there i used the equation $$m^3=10^6cm^3$$ and solved for $cm^3$ to get $cm^3$ in terms of $m^3$
Duh Hello
and where did you get the 10^6 from?
from that $1 m^3$ is 1 million $cm^3$
Duh Hello
maybe i should switch away from scientiffic notation
seems you are getting confused by it
10^6 is 1 000 000 no?
yes
how am I getting confused
so why is it hard for you to get $cm^3$ alone?
I just don't understand the logic behind the formulas you are using
Duh Hello
because I don't know the method
its just dividing both sides by 1 million
in words, 1/(1 millionth) of a m^3 is 1 cm^3
I feel like you are jumping over steps. I have cm3 and I want to get to m3
how can I do that?
I don't know where you get your numbers from
you find an expression for cm^3 from m^3
and since you know the relation $$m^3=(100cm)^3=10^6cm^3$$ you can then divide both sides by $10^6$ to get $$cm^3=\frac{1}{10^6}m^3$$
Duh Hello
I don't know that relation
the other guy told me that m3 was not equal 100cm3
exactly. and you found that 1 m^3 is 1 million cm^3
after some time
and now i have been using that
how can 1m3 be 1 000 000 cm3
i thought you understood it at this point
you haven't explained it. You just stated it was the case but I don't know the method for calculating it
follow this
i was explaining it here
but you seemed to understand it
since you had the right answer while i was typing it
either way i think you have the wrong mindset when it comes to math. you just want to know how to do things with zero understanding of how it works. this will lead you down a bad path. i think im gonna have to call it quits here, maybe someone else can help you
I'm not sure what you mean by that. I'm trying to figure out a method I can use for converting this
anyways thanks for taking the time
I appreciate the help
would probably ping helpers
@hidden steppe Has your question been resolved?
convert each unit using powers of 10
show ur workings
where did u go wrong?
I don't know how I can convert cm3 to m3
ok
how many cm in 1 m?
@hidden steppe
@hidden steppe ??
10^2
yes makes sense
0.01
what
converted each of the 1 cm to meters
I don't understand the 2nd line
0.01
1 cm^3 = 1 cm * 1 cm * 1 cm
= 0.01 m * 0.01 m * 0.01m
= 10^{-6} m^3
what is last line
I don't understand it
10^-6 = 1/10^6
what??
no z
no I don't understand
what??
the last line
yes
what grade r u in?
I am not in school
doesnt mean that you dont know basics at all costs
r u srs?
yes
graduated with what
but I forgot pretty much all math I did
so I had to redo everything
I know how to multiply
when you multuply 0.01 by 0.01 by 0.01
idrc how u get the answer
so do u get the answer?
yes or no?
yes
ok
0.000001
I have no idea what you mean
this is in meter cubed
and is = 1 cm^3
and that was ur q
so done
gl
multiply this by 2.5 then
I don't understand why that number is relevant
because it shows how many m^3 in 1 cm^3
I still have no idea how to solve my problem
that doesn't help me
ah srry cant help i gtg
alright thanks anyways for taking the time
<@&286206848099549185> could someone help me with this problem please
@hidden steppe Has your question been resolved?
<@&286206848099549185>
i got you bro
@hidden steppe Has your question been resolved?
<@&286206848099549185> could anyone help me
Ok so
Im not on pc so i cant use latex but try to understand me
1kg = 1000g right
yes
I don't follow
So basically when you are converting "cubes"
If you jump for example, from m³ to dm³
You multiply by 1000
1 step = 1000 units
Ok?
I see, is it the same principle for m2 to dm2? but with 100
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Why does that say 25 marks?
I'm not stupid
I'm questioning if that's a test or not
look at the numbers man
<@&268886789983436800> Got a troll
cheers
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yea simplifies to 8x+13y=130
,w Plot 8x+13y=130
No I just did it without any reason
Wait you have to find x+y
ya
plotting isnt necessary bro its trigonometry
13+2=15
how u get 13 and 2
It is triangular algebra cause I have to find integer I have to find by using graph
It would be easier
8x+13y=130 there are some other possibilities like
x=0 and y= 10
But we know that x and y are positive integer so
Yeah
Bro at first I was confused but when I saw the integer word I got that in my mind
no
it should sum up to 180
it does
Yupp
how would u propose to do it
,w plot x^2 + {y -3/4(x^2)^(1/3)}^2 = 1
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Hey there, I would appreciate some advice to approach the following question (underlined and circled part).
This is about joint continuity of partial derivatives of the jacobian. Currently seeing this in Calculus.
Thanks!
@plush juniper Has your question been resolved?
I feel like you should include in information from the start of the question.
Does your book say what jointly continuous means?
I just get statistics stuff when I search for jointly continuous.
Yea true I cant seem to easily find this on the internet as well
Oh. I think that's uniform continuity.
Well for x > 0 each of the partial derivatives are continuous and continuous functions are also uniformly continuous.
I think showing they are continuous for x > 0 will be enough.
so I got these partial derivatives, how do i check if the bottom left arrow is continuous?
They are all clearly continuous for x > 0. Proving them seems unnecessary though.
I think just saying they are all defined for x > 0 will be sufficient and the rest of the problem will come from showing that the jacobian 2(x^2 + y^2)/x^2 > 0.
Ok, the thinking process is the following:
- Each partial derivative is continuous and such is uniformly continuous
- If all are uniformly continuous then x and y are also jointly continuous
Is this right?
I think that jointly continuous is just your courses terminology for uniform continuous.
But in this it uses the derivatives of the function at a particular point right? I don't think the definition I got uses that.
They seem very similar but your definition defined it for a point but has the conditions to be satisfied on a neighbourhood about it.
x', x'', y' and y'' are not derivatives in my image. Just names for points.
I see
I'm just noting the similarity between them so I think they might be equivalent. Which then allows us to only need to explain why they are continuous.
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1/3 + 1/6 = 2/6 + 1/6 = 3/6 = 0.5
1/3.5 + 1/5 = 14/35 + 7/35 = 21/35 ≈ 0.6
Is this correct?
How is 1/3.5=14/35?
hmmm not quite
Oh, should it be 10/35?
yes, try to be consistent with your numerator and denominator scaling
yeppie
17/35 ≈ 0.5
Right?
yeah
good job
Thanks
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Why would the pointwise limit not be integrable? Isn't it just infinity at 0 and 0 elsewhere? Which would be measurable with integral 0, no?
@raven stream Has your question been resolved?
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Hi all. [Real Analysis]
I'm proving that the sequence 1/2, 2/5, 5/12, 12/29, ... , x_{n+1} = 1 / (2 + x_{n}) is convergent
I need to show that the odd terms (n starts at 1) form a decreasing sequence and the even terms form an increasing sequence.
I already figured out that x_{n+1} - x_{n} = -2 (x_n^2 + 2x_n - 1) / (5 + 2x_n)... which means that for x_n < sqrt(2) - 1, it is decreasing and for x_n > sqrt(2) - 1 it is increasing.
My question is: how do I tie this information with the subsequences? I mean, how do I guarantee that the odd sequence will stay above sqrt(2) - 1 and the even subsequence will stay bellow sqrt(2)-1?
Sorry I was writing the full thing and hit enter by mistake
x_1 = 0 i guess ?
x_1 = 1/2
Hi all. [Real Analysis]
I'm proving that the sequence $1/2, 2/5, 5/12, 12/29, ... , x_{n+1} = \frac{1}{ (2 + x_{n})}$is convergent
I need to show that the odd terms (n starts at 1) form a decreasing sequence and the even terms form an increasing sequence.
I already figured out that $x_{n+1} - x_{n} = \frac{-2 (x_n^2 + 2x_n - 1)}{(5 + 2x_n)}$... which means that for $x_n < \sqrt(2) - 1$, it is decreasing and for $x_n > \sqrt(2) - 1$ it is increasing.
My question is: how do I tie this information with the subsequences? I mean, how do I guarantee that the odd sequence will stay above $\sqrt(2) - 1$ and the even subsequence will stay bellow $\sqrt(2)-1$?
Max..
just so i can actually read it easier lol
That's cool, thanks
i think for this question you need to show that the sequence is bounded and it's montonically increasing or decreasing
Yes exactly.
first of all we know $x_n>0$ so $x_{n+1}$ can be bounded from above
Max..
The $\frac{1}{2 + x_n}$ gives us the 1/2 upper bound, since all $x_n > 0$
yeah nice
then you have shown $x_{n+1}-x_n=\frac{-2 (x_n^2 + 2x_n - 1)}{(5 + 2x_n)}$
im not sure where you got that?
$x_{n+1}-x_n=\frac{1}{2+x_n}-x_n=\frac{1-2x_n-x_n^2}{2+x_n}$
Max..
Oh, I jumped some steps... this comes from the rule for skipping one element... $skip_{n+1} = \frac{2 + skip_{n}}{5+2*skip_{n}}$... since the original sequence is alternating, but the skip elements are all decreasing (for the odd ones) and increasing (for the even ones)... I mean, that's what I have to show...
keepitalphanumeric
ah ok ic
So odd(1) = 1/2, odd(n+1) = skip(n+1); even(1) = 2/5, even(n+1) = skip(n+1)... just to define what I was talking about...
1/2 is above sqrt(2) - 1, I hope to show that all odd(k) stay that way. While 2/5 is bellow sqrt(2) - 1, and I hope to show that all even(k) stay that way...
I mean for even it's easy as you can show it's monontically decreasing between even terms by the fact x_2=2/5 < 0.414 (sqrt(2)-1), then for even terms it's monotonically increasing
The original sequence is oscilating towards the limit... Both the even and the odd subsequences converge to the same limit.... like a dampening sine wave kind of thing...
The original sequence isn't monotonic, but it's even and odd terms are.
At least that's what i'm going for...
my bad yea i got confused with increasing and decreasing lool
yeah i mean you've got it no?
you've found the difference between the odd and even terms
and then as they are monotonically increasing but bounded above and monotonically decreasing but bounded below you have shown both sequences converge
you havent shown what it converges to but you've shown it converges
My problem is garanteeing that it doesn't overshoot the limit... why can I say that from one step to the other this subsequences doesn't pierce the sqrt(2) - 1 bound (I mean how do a garantee that all odd terms will stay above, for instance). They are above and decreasing, but they may decrease too fast and pierce the limit ... I have to prove that they can't do that.
I mean, why is odd(k) > sqrt(2) - 1 for all k? Once I establish this, I can say that for all k, odd(k) is decreasing... But, I have just shown that at k = 1, odd is decreasing (since 1/2 is greater than sqrt(2) -1 ).
My question should be rephrased to:
I think you can create new sequence y_n = x_n - (sqrt(2)-1) for n is odd and (sqrt(2)-1) - x_n when n is even
and prove than y_n > y_(n+1)
i'm thinking about it...
Actually i can prove that ||y_n+1 < y_n/2||
@dense yacht Has your question been resolved?
Hint: ||In original recursion, minus both sides by sqrt(2)-1 and use conjugate on fraction side||
@devout flume Cool. I think I got it.
$y_{n+1} = \frac{1}{(2+x_n)(sqrt(2)+1)}} * y_{n}$. So {y} is decreasing.
keepitalphanumeric
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Now why can I say that Y is bounded by sqrt(2) - 1? I have to use a previous knowledge that the original sequences were bounded by that, right? I keep coming back to this statement.
If limit of y when n->inf is 0, then we can guaranteed that sequence x_n converges
it is the definition of limit
the epsilon thing
Once I know that each subsequence converges to that same limit, I can transform the original sequence into Y, and know that lim Y -> 0. Got it! Thank you so much. This problem was destroying by brain! I am finally set free! hahaha THANKS! @devout flume @compact wraith
It is nice problem tho
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in the interval [1, 7] why is 4 a local maximum
cookie2
And so the only critical points are 0 and -8 right?
but they are not in the interval
cookie2
Ok this is the derivative
wait a second I'll do it on a piece of paper
ok
wait a second, are you sure there isn't a mistake in the derivative you've sent?
yea
that's the derivative
and now you try to tell where is the top fucntiuon positive and when is it negative
you can then tell where the local maximum is
do i just plugin random numbers?
nope try to find P(x)=0
P(x) being the thing on the top
you can use the quadradic formula or idk hiow it's called
yea now that you'vefound the derivative you find the solutions of the polynomial on the top so you can tell when it's positive and when it's negative
then you find that 4 is the number at which the derivative goes from positive to negative
thus it's a local maximum
@unique basalt did you solve ?
@unique basalt Has your question been resolved?
ive been trying, idk how to solve it
i dont know how i get a 4 anywhere
I think its just my algebra
you fiond the solutions of the polynomial on the top
i needed to simplify the parentheses
oh maybe idk but the thing is that you have to find the roots of the polynomial then factor the polynomial out thanks to the roots
and then you can easily find the sing of the polynomial
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L1 = {w ∈ I⋆ | w is divisible by 2 or 3 when converted to its equivalent decimal number}
I'm supposed to design a NFA for this
But I'm a little confused by the "when converted to its equivalent decimal number" part
@quick leaf Has your question been resolved?
@quick leaf Has your question been resolved?
<@&286206848099549185>
@quick leaf Has your question been resolved?
does it look answered 😭
@quick leaf Has your question been resolved?
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@glass carbon from yesterday if the answer was 2.708
If u convert to a mixed fraction
There is no answer given
Result:
2.7083333333333
it's not 2.708 !!!
Then why did the calc say it
Modus
,calc 2 + 17/24
Result:
2.7083333333333
There should be an option in your calculator for that
Ye
But I would need to know how to do it irl in case the teacher asks how I solved it
,w how to convert decimals into fractions
Wolfram Alpha doesn't understand your query!
Perhaps try rephrasing your question?
Click here to refine your query online
This app is very stupid
just work on fractions
you'll get that
$$\frac{5 \cdot 6.5}{12}=\frac{5 \cdot 6\frac{1}{2}}{12}=\frac{5 \cdot \frac{13}{2}}{12}=$$
$$=\frac{\frac{65}{2}}{12}=\frac{65}{2 \cdot 12}=\frac{65}{24}=$$
$$=2\frac{17}{24}$$
Modus
I should pay u for typing this
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is this correct
.close
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I’m not too sure how else to prove it
so how can I solve this problem? I know how to normally determine dy/dx but I'm not sure what to do regarding the logarithmic differentiation
oh this channel is already occupied sorry.
So you know induction?
@lean otter Has your question been resolved?
Uhhh didn’t learn that yet
@lean otter Has your question been resolved?
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Does anyone know how to solve this?
i have already tried to let z = c + di and formulated an expression that satisfies the required solution form: d = 3c - 2
thus, z = c + (3c - 2)i
i then expanded the modulus equation using the conjugate property zz* = |z|^2
i am stuck here...
<@&286206848099549185>
@novel thicket Has your question been resolved?
<@&286206848099549185>
Can you show how much have you done from there
hey, thank you so much for responding
i have stated what i have done so far
in the end, i derived an equality in terms of a, b and c
but, i was not sure how to proceed from there
Ok that equation is true for every c right?
yes
but i need to find specific a and b
I think you can compare coeffcient of 1,c,c^2
wait, can u show me how u would approach the derivation
to compare my equality with yours, bcs i am not sure if it is correct?
Well i didn’t do yet. But it must be able to write in polynomial of c
it would be greatly appreciated if u could derive just the equality so i can compare my answer with yours
i can then take it from there and apply ur suggestion
thanks
to get the first expression, did u use the conjugate property or the modulus definition |z|^2 = c^2+d^2?
so u would then construct a system of equations
but, u would then have two equations for 3 variables which is a deficient system right?
💯
@novel thicket Has your question been resolved?
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Consider the function g(x) = −2x² + 3x + 4. Which inequality correctly orders the values of g(−3), g(3), g(0), and g(2)?

