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I was trying to do this excercise but I can't think of any other function then sin or cos to have this property
can I just say f(x) = sin(x) and then I know the series of it which is
and radius of convergence is infinity
no, the nth coefficient of the sine expansion doesnt match the n+4th coefficient
oh wait u are right its' because of the n!
oh wait is it a geometric series?
oh nvm
you can try expanding and see what has a common factor of $c_0$, $c_1$, etc
anonymemes
well when i write it out it's c0 + c1x1 + c2x2 + c3x3+ c0x4 .. etc
okay
yup
and also for c1 .. c3
yup
but will that help me
I have written it out but I still don't know the general formula
okay. similar to $c_0$, what did you get next to $c_1$?
anonymemes
x^1 + x^5 ...
okay, try taking an x out
for c2 it's x^2 + x^6 ...
try taking an x^2 out, etc
oooh that's so smart
the common factorr is that (1 + x^4 + ...)
exactly
is it allowed to say that (c_0 + c_1 x + c_2 x^2 + c_3 * x^3) ( 1 + x^4 + ...) is my general formula?
no you're not at your general formula yet
oh
the common factor can be made into a sum right?
let me see what the sum is
(and what it equates to)
yup
yes
yeah
yeah so thats ur radius of convergence
the infinite series becomes a function in this radius right?
interrval is just (-1,1 ) btw
oh wait ye
1 / (1 - (x^4)
and that I do times the c_0 part
(c_0 + c_1 x + c_2 x^2 + c_3 * x^3) / (1 - (x^4))
is this my general formula?
exactly
I can call it my general formula since it's not infinite right?
yup
and uhm this part:
(c_0 + c_1 x + c_2 x^2 + c_3 * x^3)
radius of convergence is just infinity or don't I have to look at that?
its a finite polynomial, so it has an infinite radius of convergence
ye so I take the intersection of radius of convergence right?
which is 1
yup
and the interval is just (-1,1) since thats also for the gemoetirc series
yes
you're welcome
if u have time can I ask 1 short question which I am confused about
I was doing excercise 9
and I found the power seires representation
which is summation of ((-1)^n * x^(4n+2)) / 2^(4n + 4)
so basically I learned to radius of convergence to do it 2 ways
one is with ratio test
other one is this
which is basically faster way
but it was not working this time
the ratio test was working tho
do u know why?
one sec
ofc
to clarify u take x^2 / 16 out to get a geometric series and basically simplify after that
so why did that one not work exactly?
yeah i understand, your formula is correct
uhm I forgot I did this one like a couple hours ago and I accepted that it didn't worked lol but now that u can help me I thought I might aswell ask 1 sec I will try it again and see why it failed
ye so c_n = (-1)^n / 2^(4n + 4)
just to clarify if I did that step correct
yup
ye so from that formula I get R = 16
but with ratio test I got | x | < 2
R is the radius of convergence for x^n. since you had x^4n, you had to take your R to the 1/4th power
ooh this is making sense
alternatively, changing n to something like k/4 in your sum would make it in terms of x^k
and for ratio test u got | x | < 2 so u already have it to x^n
ye that one might work aswell
although that prob is a bit more effort
I feel like this is the easiest to do
yeah. i would do the sum stuff tho just incase
is that like safer option?
I feel like if I do that isn't ratio test faster?
or about the same speed
yeah if you wanna be more rigorous
but i think you can just say $|x^4|<R$ and do stuff
anonymemes
I tried it on this one so if I am correct it's the summation of k = 0 to infinity
(-1)^k/4 * x^(k+2) / 2^(k+4)
ye this one seems fastest to me tbh
also make sure to check the sum manually for + and - R because the tests dont test those
ye I've rmeembered that
but if I do this
will it go wrong?
because this seems like fastest way to me
i dont think it will but i can check
I know lim n to infinity with c_n / c_n+1 is just a derivation with the ratio test for power series with x^n is that the reason why it may go wrong?
yeah it shouldnt go wrong if you know what your x powers are
anyway like you said its basically the ratio test with a mask on so do whatever you like
ye so if u got smth like x^12n + 25 with that formula I get
|x^12| < R and then just take both to 1/12th power
yea
ye tbh I can always do the ratio test as a doubel chcekc it's just that I found this one faster
yeah double checkin is a good idea
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not sure about this section
not sure how they got 2b1 from
because the only equation I see that relates is this one, so b1 = 2b2-2a2+a1^2
From here you'd have $a_{k+1} < b_{k+1}$ and also $b_{k+1} \leq b_k$
@unreal musk
One line below 
Cause you have $a_{k + 1} < b_{k + 1}$ you get that the $\frac{b_1 - a_1}{2^k} \qty(b_{k + 1} + a_{k + 1}) < \frac{b_1 - a_1}{2^k} \qty(b_{k + 1} + b_{k + 1} ) = \frac{b_1 - a_1}{2^k} \qty(2 b_{k + 1})$
@unreal musk
The fact the intervals are nested forces $b_{k + 1} \leq b_k$ for each $k$, so you can iterate that backwards to then get $\frac{b_1 - a_1}{2^k} \qty(2 b_{k + 1}) \leq \frac{b_1 - a_1}{2^k} \qty(2 b_{k}) \leq \frac{b_1 - a_1}{2^k} \qty(2 b_{k-1}) \leq \ldots$
@unreal musk
[you're happy with why this is the case at least, right?]
if you iterate this enough you get to b1 in there
yes, visually, b2 and a2 with the two diff cases would be the midpoint of b1 and a1
like binary search in programming
thank you!
I'll prob just stay in this channel
working on lots of proofs today
Can someone help me
!occupied
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@tawny kite Has your question been resolved?
@tawny kite Has your question been resolved?
@unreal musk I dont really get the sup = inf part
sup is least upper bound, why is it saying r<x?
least upper bound where r is less than x?
They're kinda saying "take the all rational numers that are less than x, and work out a^r, and make that a set...
...from that set, take the least upper bound"
"kinda" like you're taking larger and larger rational numbers getting closer and closer to x to work out a^x via the a^r's
You know how to work with rational powers, so define the irrational powers via rational powers, if that makes sense?
(similarly, the "inf" part is saying "take all rational numbers r greater than x, work out a^r and put those in a set, and of that set, take its greatest lower bound)
Im actually gonna go back to the original question I asked
I was trying to explain it to my family haha just for fun
and I realized I have no idea how the last expression we found relates to a-b^2. The last sentence proving existence
waitttt
actually no
why would finding a sufficiently large k be a contradiction?
yes we know that bk+1 ^2 -ak+1^2 is less or equal to b1/2^k(2b1)
but there is nothing that says it cant be bigger than |a-b^2|
That difference is supposed to vanish basically (because of that 2^k in the denominator)
But if you had this, any other larger k's would also be bigger than |a - b^2| and means that it wouldn't be able to vanish
ohhh
so because its b1/2^k its going to 0, indicating that bk+1^2-ak+1^2 is '0'
so statement contradicts
Yep 
yea! thank you thank you ๐
@tawny kite Gonna get a bit of sleep now 
ok!
Most likely will catch ya later 
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hello
HI
i nees help bro
bro dis my channel
in maths
I'll give you a hint: f'(x) = 0 when slope of f(x) is 0
hi zap
ahh that makes sense
but what if it was a scenario where there wasnt a horizontal tangent
More than likely you will rarely encounter that, You will just need to get good with seeing the relationships between the graphs
alr thx
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https://webspace.ship.edu/msrenault/geogebracalculus/derivative_try_to_graph.html
I found this interesting site if you want some practice (These seem pretty challenging though)
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So im essentially wondering the best way of figuring out a function from the following data set:
1/0
2/0
3/0
4/0
5/0
6/0
7/3
8/4
9/4
10/5
11/5
12/6
13/6
14/6
15/7
16/7
17/8
18/8
19/9
20/9
21/9
22/10
23/10
24/11
25/11
26/12
27/12
28/12
29/13
30/13
31/14
32/14
33/15
34/15
35/15
...
The pattern is repeating, and X โ W, this isnt from a specific question in some homework, i am just curious on what would be the best method of trying to define a function for this thing.
huh, what is the data?
Are you wondering if there is a way to find the relational properties of those fractions?
When x โ [0,6] = 0
And when x is 7+ theres a pattern
My goal is to turn this data into a function, probably using floors, my question is how do i go about it? What would be the method? Just throwing out functions and seeing what sticks?
They arent fractions, i shouldve formatted them better. These are x and y values, so like (7, 3)
Apologies for the confusion
X also belongs to W, as in whole numbers. It cant be negative or a fraction, nor can y
Id explain where im getting the data but its a long story
how exactly are they repeating? are we just ignoring the beginning and assuming the 2 2 3 repeating continues?
like 2 13s, then 2 14s, then 3 15s
Yes, we're assuming
The single 3 in the beginning can be chalked up to an irregularity
Then we can assume the pattern is 2 3 2
Or if we need to (which i kinda assume we do) chalk up the first 5 into irregularities and start at (15, 7)
So that we get 2 2 3
ok i have an idea it will take me some time to set up and check though
Thank you, i appreciate it
Id love to learn how to get functions from data sets like these
But does that work as a function?
Id have a hard time getting an output from that if i inputted like, 1034
yes i think, it is a function
I honestly couldnt tell ya if it is, im not sure how the k works into the equation
my idea won't have any if statements if it works
as i restricted that k is a integer, every x would, and would only satisfy one of them
I see
but the domain of this func only contains integer and it's make sense, that's enough for this question
The domain only includes whole numbers though
wdym numbers
natural number u mean?
Sorry i havent slept, yea i think im being stupid
Or am i?
Natural is 1, 2, 3
Whole is 0, 1, 2, 3
Integers are with negatives
Then rational and irrational
Which are all real
No?
natural number includes 0 i think
I dont remember tbh
anyway, any questions?
Not really no, thank you :)
i think i have a computer friendly answer
actually has an issue but i think it's almost ready
lol ok
$f(n) = \left\lceil \frac{n \operatorname{mod} 7}{2}\right\rceil - \left\lfloor \frac{n \operatorname{mod} 7}{7}\right\rfloor + 3\left\lfloor \frac{n-1}{7}\right\rfloor - 3 \left(\operatorname{sign}(n \operatorname{mod} 7)-1\right)$
soulgazer
this generates 1,1,2,2,3,3,3, 4,4,5,5,6,6,6 etc
can shift it accordingly to match the data
so....
$f(n) = \left\lceil \frac{(n-7) \operatorname{mod} 7}{2}\right\rceil - \left\lfloor \frac{(n-7) \operatorname{mod} 7}{7}\right\rfloor + 3\left\lfloor \frac{(n-7)-1}{7}\right\rfloor - 3 \left(\operatorname{sign}((n-7) \operatorname{mod} 7)-1\right) + 3$
wait
soulgazer
i think that should have f(8) = f(9) = 4, f(10) = f(11) = 5 etc
@wide pewter Has your question been resolved?
That is so fuckin crazy im ngl
I thought itd be a lot simpler with using some dividing and floors but wow
Bro i dont even know what mod does, that is so cool
i'm sure it could get simpler
Thats still so cool
Youre a legend
I think you deserve to know the context
Although its so stupid you might strangle me for it
don't worry i wouldn't strangle anyone
In a server im in, big public one
They have a bot that deletes messages with too many caps
But
You can offset it with some small letters
So if i went
YABA DABA DOO
Thats 11
Itd get deleted
But
If you made it
YABA DABA DOO yknow?
Itd be fine, x = 11 and y = 5
X is the letters that are capitalized, and Y is the ones that arent
I was just so perplexed and intrigued on what basis it was getting rid of messages on
And wanted to know if i could reverse engineer the system
I was initially just gonna look for help on gettin started as my best method to go about it wouldve been making up functions, testing em, and then makin more if it didnt work
haha what's weird about being curious about that
Its out of the blue and so gut wrenchingly stupid lmao
Its a frickin discord bot and if i was so curious, i could probably just ask whoever made it
But either way, thank you man. This was awesome
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i'm gonna guess it doesn't run on this
Probably not lmao
but it might as well
also that won't work for n < 8
but those are special cases anyway
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How to know if these 2 are congruent?
A good way is to try to draw them
@scarlet anchor Has your question been resolved?
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Part A,
Everytime I do such a question
I get confused why the formula
sn = n/2 (a + L) doesnt work L being last term
a (first term) is k+1
d (constant) is k+2
Why does
sn = n/2 (a + L)
303 = n /2 ( k+1 + 303)
x2
606= n (k +304)
606/ k+ 304 = n is wrong
why is that wrong?
The correct working out is
sn = a + (n-1)d
303 = k+1 + (n-1) (k+2)
303 = k+ 1 + kn + 2n + -k -2
303 = kn + 2n -1
303 = n(k+2) -1
304 / (k+2) = n
How is my frist method wrong
Im confused ty ty
@graceful marten Has your question been resolved?
I think i understood why kinda?
Bc the first one is the # of terms to make the sum 303?
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โ
I have a Question
So A,
Is done like this
sn = a + (n-1)d
303 = k+1 + (n-1) (k+2)
303 = k+ 1 + kn + 2n + -k -2
303 = kn + 2n -1
303 = n(k+2) -1
304 / (k+2) = n
If I were to be asked,
Q2. How many terms would you need to make 303
Would that also be done through the same method as the above? (A)
And If I were to be asked
Q.3 the sum, of terms to 303
Would it be done like this?
sn = n/2 (a + L)
303 = n /2 ( k+1 + 303)
x2
606= n (k +304)
606/ k+ 304 = n
@graceful marten
Yeah?
@graceful marten Has your question been resolved?
Yes for a it's done like that
For question b
Use the formulas sn = n/2 (a+L)
from question a you found out the value of n and L is given in the question
sn = (304/2(k+2)) * (k+1+303)
sn = (154/k+2) * (k+304)
sn = (152k + 46208)/(k+2)
Hence proved
For question c
you have founded the value of Sn in terms of k in the question b
Yeah C->
2568 = QB
k = 17
Yep
Since your here I hope you dont mind
?
Iโm a bit unsure where I went wrong
What I did is use the Last n'th term being the
un = ln9 ect
And throw it in
Sum of first n terms sn= n/2 (a +L)
A being the first term, and L being the last term
Last term being (un) in question
Unless that is me understanding it wrong (un) is not the last nth term
Wait let me check it
Oh my answer came out too
Same thing as I ?
No its
1/2 ln^(n^2+3n)
a is 1/2
mentioned in question
yeah
thats correct
I found my mistake after 30 min of chat gpt and doing it 3 times
It's just a Lil bit tricky
I did ln(9^2 x 3^n)
Dude ๐
2*
ok
a^m * a^n = a^(m+n)
Is your question resolved now?
My pleasure
Same
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Im having a problem with maths,
Instead of using log, i tend to use ln (just bc it confuses me less)
Is it alright if I get all the working out to
5 ln p + ln 5 = 0
and then convert it to 5 log p + log 5 = 0
[Bc the question asks me to prove you get ' 5 log p + log 5'
Can I do that for all questions
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Does "a number of the form 2^m * 5^n" include 30?
consider the prime factorisation of 30
You need a factor of 3
Because 30 would be 2^1 * 5^1 * 3 but 3 is not mentioned in the given form of the number
So 30 wouldn't be of the form 2^m * 5^n?
can you multiply any number of 2s and 5s together to get 30? (without using 3)?
No I dont think so
No
so 30 can't be expressed in that form (assuming m,n are integers)
I saw a question saying this-:
Assertion: 6^n will never end with the digit 0 where n is a natural number
Reason: Any number ends with digit zero, if its prime factor is of the form 2 ^ m ร 5 ^ n, where m and n are natural numbers.
I know that the Assertion is true
But the reason should be false
But everywhere on google it is being said that the reason is false
If a number ends with zero it must have a factor of 5 and 2 so whats the problem
And the thing is that teachers would blindly follow the answer on google and not listen when someone has a question
Oh I see they said no more factors
?
Yeah
No ig they wanted to say at least 5 and 2
where'd that reasoning come from
What reasoning
Reason: Any number ends with digit zero, if its prime factor is of the form 2 ^ m ร 5 ^ n, where m and n are natural numbers.
It should be multiple of 10
But it could have other factors apart from 2 and 5
Thats the problem
was that part of the question? were you being asked whether this was a valid argument?
Yes
They're asking us whether the Assertion and reason are true or false and if they both are true, is the reason a correct explanation for the Assertion
They should have written 'at least' or something like that
It could have more factors obviously
yeh, so like you said
the assertion is true
but the reasoning is invalid
The problem with these types of questions is that sometimes teachers say you're thinking too much about it and sometimes they say we have to find technicalities and mistakes in the statements
note that the implication only goes in one direction
prime factor is of the form 2 ^ m ร 5 ^ n, where m and n are natural numbers
results in a number ending in 0
but doesn't work the other way
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Idk why am I stuck on this
Im sure its easy but I just dont know why cant I think of the way to do it
I think this is bayes theorem?
Havent heard about that thing
I thought making diagram would help but I cant find the stuff union intersection and uhh
you should probably check 3blue1browns video about bayes theorem cause I think this is bayes theorem
you can probably think of it as an area of a rectangle rather than a venn diagram
yeah bout bayes theorem
the question is really hard to grasp if you only think of it as percentage, much better if you make it to actual quantifiable numbers
no idea what i did
but I couldnt make any use outta it
now talking about bayers lemme go check it
I think
it says maximum students who can either not sing or not dance
total number of students - ( students who can sing and not dance)
GOT IT
40 - 38
2
yeahh
thx for ur help anyway ๐ @oak bear
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Hello, how do I continue this?
@cobalt scaffold Has your question been resolved?
@cobalt scaffold Has your question been resolved?
what's the question
@cobalt scaffold Has your question been resolved?
i can help kindly message
Oh okay, thanks
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honestly havae no idea where to start.. ive missed a couple of lectures and i feel really behind ๐ญ
do u want help on how to do it
or do u just wanna know the answer
both i think
The expected value is 1/lambda
i want to know how to do it and if im doing it right
So lambda = 1/80
The probability density function is lambda e^(-lambda x)
So just integration
Also the exponential distribution is memoryless
It doesn't depend on previous events
So for b the time would start again at 0 minutes at 9:25 am
And tricks like P(at least 1) = 1 - P(none)
how come we're using the probability density function and what does thjat function mean
Probability density is a term used in statistics for continuous random variables. Since these variables can take on infinitely many values, the chance of any specific value occurring is usually zero. Instead, we focus on the likelihood of the variable falling within certain ranges or intervals.
so exponential distribution is a type of
probability density function
and why is lambda 1/80
and what does mean mean ๐
i feel like i dont understand anything
oh wait
average time it takes to finish the test is 80?
so 1/80 * e ^ (-x/80)
find the probability that x is less than 40?
so for the problem that asks P( at least 1 finishes before 40 ) i should do 1 - P( everyone finishes at or after 40 min) ?
or no one finishes before 40
Yeah so no one finishes before 40
And then 1 minus that
Yep
Yeah so you need to integrate
Yeah
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โ
wait @red ice would the integral be from 0 to 40?
1 - int from 0 to 40 of [ (1/80 * e^-t/80) ^ 5 ]
or would it be from 40 to infinity
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and if it starts at 0 again does that mean itll be 60 to inf
Nah 0 to 35
And 0 to 40 for the other one
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how do i do this
I found 'a' which is 2, and in 12b it says it's negative so c = -2
but i dont get how to find d
book says y=-2sin(x-210) but i wrote y=-2sin(x-30) since it moved 30 units right from the original position???
i get that 180+30 = 210 but why
hello?
It is because you can think of it as flipping the function and shifting it half a cycle
wouldnt the red one be y=-2sin(x-180) then?
too complex for me to imagine
As you noticed, 180 + 30 = 210
ah
adding 180 to 30 because 180 is half a cycle
right
And reflecting the sine wave does the same thing as shifting it half a cycle
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How do i do this?
!original
Please show the original problem, exactly as it was stated to you, with the entire original context. A picture or screenshot is best. If the original problem is not in English, then post it anyway! The additional context might still be helpful. Do your best to provide a translation.
Do you want to simplify it?
yeah
Yep
how do i add
Ye
$\frac{5^k + 5^k \cdot 4 -1 }{4}$
artemetra
@wicked ice does that make sense?
what would i do after?
Hmm
5^k + 5^k * 4 simplifies
i cant really rememeber my indices on how that works
im not really sure how to
would u just factor out the x
Soo how do i solve my orignal question
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good evening
hey
is there a simple way to solve the limit as x -- > 1 of x/(x-1)
(x-1)(x+1)
heh
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@everyone hi guys im ishowtoilet
@everyone
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<@&268886789983436800>
chill chill chill
@everyone
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dont ban me
wtf
ok i won't ban you
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you know it doesnt work right
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๐คก
Lol
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hi, I need help with this differential equations problem
The general solution to this linear system is the following:
xโ(t) = โxโ(7) + 4t + e
The equation for xโ takes xโ(t) and subtracts xโ(7), then adds 4t and e to get the linear function. You can then substitute any specific value of t to get the corresponding xโ(t) value for that t.
Well actually I didn't understand how you get there
uhh wait
The first step is to express the given terms as a linear equation. You start by writing both equations in terms of the same variable:
dx/dt = x
dt/dt = 1
Now, you can combine these two equations by adding the first equation to both sides of the second equation:
dx + dt(dt)
= x + t
This results in a single equation that contains all of the given terms. You can then rearrange the equation to find the general solution
NOW?
Oh, alright I get it now, thank you!
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Ive worked DBO AND BDO to be both 90-x, how do i get BCD in terms of x
angles in a triangle add up to 180, so (90-x) + (90-x) + BCD = 180 and you can rearrange
ah wait, I misread which angles you have
this angle is x, since it's subtended by the same arc
then opposite angles in a cyclic quadrilateral add to 180
so BCD = 180 - x
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d is the GCD
Yeah
ax + by = d
so you're saying ab | d
the next step
from this is somehow incorperating c
on the RHS?
yeah
you need the RHS to be big
so you want cd in there from the start i think
i gtg
mind quickly hinting on
b4 u go
off the top of my head, consider a/d and b/d and give them names
and like c/a and b/a maybe also
@smoky onyx Has your question been resolved?
no
really quick, sorry
is this what you meant
close
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Im having troubles understanding some basic? math rules
ok so,
They first expanded the brackets to cancel out the
1-r^2 on both sides
Becuase if you just cross multiplied at the beggining, you wouldnt get a correct answer
You would.
It would give you 4 values of r. Two of them would be +-1, which you can't accept.
oh ok I think thats whats confusing me ^
Bc I usually get x^2 + x + 4 and u would get x values
But here sometimes you get no values
or all imaginary
or just the wrong ones
How would I do it then?
Lets say from here -->
-r^4 -1.16 +1 - 1.16r^2
There are no "wrong ones"
You'd let r^2 = x and solve the quadratic.
oh
still wrong in your sign
yeah there is no equality to begin with
you had an equation and in the end you don't have an equation
Ok i think i understand
So if I had something like
30.5 = ( 8 (1-r^3) ) / (1-r)
30.5 = ( 8- 8 r^3 ) / (1-r)
30.5 (1-r) = 8- 8r^3
30.5 - 30.5r = 8- 8r^3
30.5 - 30.5r - 8 + 8r^3
what do you mean?
you had an equation and the last line is not an equation
your equal symbol just dissapeard for some reason
ok = 0 ?
yes
30.5 - 30.5r - 8 + 8r^3 = 0
ok but then im confused again
oh the equation works
Wait waht one second
Ok no this one works
Ok let me start again
sorry lol
Solving this
1-r^4 = 1.16 ( 1-r^2)
1- r^4 = 1.16 - 1.16r^2
1-r^4 - 1.16 + 1.16r^2
-r^4 + 1.16r^2 - 0.16
Oh Ok nvm
I understand
I just managed to get both wrong somehow
Sorry for this
Thank you anyways
This took me 4hrs -.-
Great
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im not sure what to do here
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the only thing I can find is k values
pls help me I dont know how I am going to find the time of his death :(
i dont have an answer but may i ask what this subject is
this intrigues me a lot
ib math aa hl

theres more formulas you have to use with this i presume, i tried to do this but i cant since there's too many missing variables
good luck ๐
I thinkkk i need to use some integral stuff but i am not sure lol
thxx 
your first goal should be to find the value for C
i gave 70.00 F for C
I hope that's true 
that's correct yeah
yeah I also found k values but 2 of them are different due to the temperature and time
lemme send you my work real quick
that will help :)
good idea lol
here you go

p.s. I am sorry I wrote "time of death" instead of "normal temp"
and i should have considered the - sign before kt 
honestly that seems like an error in the problem, not you
you shouldn't end up with 2 different k values
your work was fine tho
oh wait hold up
I think the issue is how you're setting your times
think about it this way: T(0) should be 98.6. what you're doing is saying T(9) = 80 F
and T(10) = 75
OHHH
so I would make a variable for the time of death, something like t_d
yeah thats pretty logical however should i use some integral stuff
bc we were learning differential equations at the time
they gave us this question
there would be an integral but they already solved it for you lol
T is the solution to Newton's cooling equation
which is a Differential eq
easy then 
hopefully :)
tysm u saved my life
any time :p
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Given these values, determine a line with the nearest fit to them.
My lecture notes have this about it, so I guess we need to use that
Apparently the solution is a_0t + b_0
How do we determine a_0 and b_0 though?
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hello
hi
Show that if x is nilpotent in A, then 1-x is invertible in A. A ring
i tried some things and ended up with xy = y - 1 if y is the inverse of 1-x but i dont think that's how it should be done
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hi
confused on this last part of a proof
we need to choose an $N$ so that $2 X 10^{-N} \leq \epsilon}$, the way the book chose it without logarithms resulte din choosing $N \geq \frac{2}{\epsilon}$
nchoosek
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what's the actual problem itself?
the way I did it is $10^{-N} \leq N \leq 10^N \leq \frac{\epsilon}{2}$ so I can just choose $N \leq \frac{\epsilon}{2}$ mine also seems correct is this valid?
nchoosek
doesn't really matter I basically have an algebra question at the end lol
oh
this is both for any $N \geq 1$
nchoosek
how did you get that $10^N \leq \varepsilon/2$ ?
doaby
oh did I use circular logic here?
I had
$2 \times 10^{-N} \leq 2 \times 10^{N}$
so I just chose $2 \times 10^{N} \leq \epsilon$
nchoosek
... but I didn't choose it without using logarithms
like explicitly
but even without relating epsilon yet
we have
$2 \times 10^{-N} \leq 2N \leq 2 \times 10^{N}$
nchoosek
so we can just choose $2N \leq \epsilon$ now without using logarithms
nchoosek
and this is still different than the book
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Da Mucky Boi
Da Mucky Boi
@timid silo Has your question been resolved?
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need help with (a)
you probably have a formula for area of triangle based on cross product
i think it's like $\frac12 ab \sin\theta$
hayley!
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i need help wih this probabilty thing
@agile saffron Has your question been resolved?
<@&286206848099549185>
the easiest way to go about this is 1 - P(nothing matches)
what
$P(X \geq 1) = 1 - P(X = 0)$
doaby
have you seen this?
nope
in other words, if you wanna know the probability of something happening at least once, it is the same as 1 - the probability it happens 0 times
which is usually easier to do
i don't really get it
lemme make up a problem then. let's say there's a football game. the probability that team A scores at least 1 goal during the game is 90%
what's the probability team A scores no goals at all?
10%
yeah?
so the chance of the other thing happening is 1- minus the probability
the chance of Beti getting at least 1 one of the same numbers is 1 - the probability she gets none of the same numbers
the answer was different tho
what
pls help
<@&286206848099549185>
bruh
plsss
<@&286206848099549185>
can anyone explain to me
bruuhhhhh
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