#help-33
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"we perform the operation opposite to what we see"
interesting
is there a rule for this
name*
ive no idea what the name of the rule is atm
something about equality of operations
hmmm ok ill go from there
$a = b + 2 \implies a - 2 = b$
blanket
$a = bc \implies \frac ac = b$
blanket
ok so in scenerio 1
if i were to move b instead
would it be
a - b = 2
i get the multiplication/division ones no problem
yes
so in this example
how come its not just all addition on the top
because of the parenthesis?
nvm i get it
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i have no idea how to solve this
@green rover Has your question been resolved?
<@&286206848099549185>
you have to represent it as a sin or cosine
so you have y
= some sine function
what is y in this case?
i think the dependent variable is 3.5
and independent is 2.25
that right? @odd crest
No thos are constants
Variables change
If you read the question again what are things you read that are changing in the question
That are not single values
the months and the precipitation
precipitation depends on the month
Exacly so in this case your independent variable is months
And dependent variable is prefipitation
C
So number of months is x
And the amount of precipitation is y
Yes but its not quite that simple
Unfortunately i have to take a shower
So im gonna be gone for a bit
Btw you answered the first question alread
<@&286206848099549185> can someone else help till they come back
Im back
@green rover Has your question been resolved?
@green rover do you know the general formula for sin functions?
Actually nevermind that it turns out you dont need it
Since what you need to find is the amplitude and the period
Do you know how to get an amplitude of a sin function?
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can you do y1 - y2 also?
replace them by actual numbers and try to verify if your logic is right
thats too much effort
it takes 2 seconds
is y2 - y1 the same as y1 - y2 the same thing as asking
is 5 - 1 the same as 1 - 5
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Hello :) I have a rather simple question on how to do this problem
It’s in a digital Logic class ^
I’m confused on how to get started mainly and if those problems would be the same as
5X = 1 mod 7
Rewrite it as 5x=7y+1
But recall that it can also be rewritten as 5x=7(5y+2)+1
Since the choice of y is somewhat arbitrary
Basically keep adding 7 until you get a multiple of 5
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Angle of elevation is something I just haven't quite gotten down yet. Would someone know the necessary formula to work on this question and questions adjacent?
However thorough an explanation would be appreciated.
I see, and Cosine would yield two seperate angles?
Cause the satalite seperates the angles
you can just use the cosine rule to find the angles directly
Oh it is angle of elevation
Not depression
Then use cosine law
Alright so Cosine law
, I wasn't sure how to approach it seeing as my knowledge concerning Trig isn't one to be described as vast so thanks for the help. That's all concerning the question. 👍
Watch a yt video for a visual explanation
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Well you have a good start [missing some bits but I can see what you're doing!]

One good idea is to note that
[
\abs{g(x) - c} < \varepsilon \implies -\varepsilon + c < g(x)< \varepsilon + c
]
@glass silo
Well, the idea is that we want to show that $f + g$ diverges to infinity - so, like the definition of that would be that for any $K > 0$, there is some positive real number $m_{K}$ such that whenever $0 < \abs{x - a} < m_{K}$, we have that $f(x) + g(x) > K$, right?
@glass silo
sorry why diverge lol
u mean tends to?
do they mean the same thing
but yes i agree with the sentence XD
Yea tends to infinity, different phrasing same meaning
But note how we have that basically:
\begin{enumerate}
\item For any choice of $\epsilon >0$, there is a $\delta_{\epsilon, g}>0$ such that whenever $0 < \abs{x - a} < \delta_{\epsilon, g}$, we have that $-\epsilon + c < g(x)< \epsilon + c$, and
\item For any choice of $M>0$, there is a $\delta_{\epsilon, f}>0$ such that whenever $0 < \abs{x - a} < \delta_{\epsilon, f}$, we have that $f(x) > M$
\end{enumerate}
Those are the from the definitions and my rewriting
And green tea 
I see you 🫶

Give me one second to edit that!
@glass silo


hmmmmm
wait
okay
so like
ok but yes
sorry had to do something
i understand
ok hmm
so like
Cool, but then if we took those two up there and added them together, and let $\delta_{\epsilon} = \min{\delta_{\epsilon, g}, \delta_{\epsilon, f}}$, then we then have that whenever $0 < \abs{x - a} < \delta_{\epsilon}$, we have that $-\epsilon + c + M < f(x) + g(x)$, right?
[Alternatively I could've written that $f(x) + g(x) > -\epsilon + c + M$]
@glass silo
wait reee where did that come from
oh wait
oh
IM STUPID
okay
i get it
okay
wait
is that sufficient
Cool cool, now this is almost what we want for the definition of divergence...

See how it's been written here, it would be much nicer if we could have this here(!)
But we can pick our $\epsilon$ and $M$ such that we can get that, based off a given $K$
@glass silo
wait did we just introduce the K
[I used the letter K rather deliberately so that it doesn't get confused and it's clear what we're doing here]
Me mind reader 🔮

Anyways, based on that $K$, I would quite like to choose an $\epsilon$ and $M$ such that $-\epsilon + c + M$ cancel down nicely to $K$
@glass silo

Do you have any thoughts on what choice you'd like to make for epsilon, and for M?
The sad cat? 

hmm
can i choose the bigger one?
Hmm, what do you mean by that?
We're given a K, and want to choose an epsilon, and an M
oh wait
i thought u meant choose K from episolon and M
hmm
could we do K + epislon + M?
wait then thats similar to the previous one hmm
Welllll, that isn't exactly an answer to the question really 
This one is a bit of a think 
i cant think
We have quite a bit of the work done for it 
Welll limits are part of analysis tbf 
I mean the hint is to look at the definition you know
hmm
ok just to be clear
we have arbitrary K
and i want to find espilon and M from K
K is anything right
Anything positive yes
hmm
[though with that said, negatives should be fine without affecting the definition I think? Do you have the definition from like your course that you're working with?]
Wellllll, if we assume that c is positive non-negative for the time being...
are we allowed algebra on limits btw
no eyedea
if we are
HMMMMM
it immediately follows 
...then we would have that this here, we can say that
[
f(x) + g(x) > -\epsilon + c + M \geq M - \epsilon
]

@glass silo
yes
Given a K, we would like to choose a M and an epsilon such that the M - epsilon becomes K
There's a rather nice choice we could do for that, right?
wait i get the idea but like
we just birthed the K out of nowhere
are we trying to use K as a lower bound (sorta)
for the infinity
That's the idea - we are given a positive K, and we want to then get that we can force f + g to be greater than that K over a certain interval
That's the explicit definition of diverging to infinity
sorry am i being dumb D:

You can't equate K to anything
You can equate epsilon and M to whatever you want though...
here's an idea, why not we try letting M-eps = K

Wait but i thought we cant do that
we're not touching K
let K = M-eps not o-K
let M-eps = K this is ok
the first one says we choose K based on M-eps which is not fine
the second one says we choose M and eps based on K, which is okay
so be specific about what
that's why the word "let" exists
[and remember that we said that we want it such that M - epsilon "turns into" K based on the choice of M and epsilon]
2 - 1 = 1, quik maffs
WAIt
Something just snapped
Ok sorry i kinda need to go
But
I got the idea
Ill attempt it again
Without referencing
@glass silo @nocturne fiber
Tysm gyts
Guys
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I don t understand how to calculate this i need help
i have to find which is correct here
the answers is sqrt(1/4b) but i don t know why
$\sqrt{\frac{1}{4}b}=\sqrt{\frac{1}{4}}\sqrt{b}$
jay.
this rule
there is a minus in front
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Hi! I could use some help with the following question:
What i think i have to do first, is write up a polynomial with the p(4) and p(-4) = 0, so:
(t-4)*(t+4)
But i get unsure when i progress here, am i supposed to try to copy the polynomial below? If so i need to multiply with another (t-4)
yes, this is right
every element of your base should have this factor correct
you want to write the poly as a multiple of (t-4)(t+4)
Alright, So will I write the poly like: a2xt^2 x (t-4)(t-4), a1 x t x (t-4)(t+4), a0 x (t-4)(t+4)
Or have i missunderstood?
sure, thats fine (what you have written is equal to (a2*t^2+a1*t+a0)(t-4)(t+4))
ah ok, so that should be the polynomial right?
Alright!
So find the coefficients so that it relates to the polynomial in the question? t^3-4t^2-16t+64?
equal to that poly, yes
Ok, then i get a2=0, a1=1, a0=-4
$\polylongdiv{x^3-4x^2-16x+64}{x^2-16}$
Toby
yup correct
How do I go forward now? I have the coefficients, how do i determine a base for H and the coordinates?
you already found the basis to be (t-4)(t+4)
the coefficient is a1=1, a0=-4. ie (t-4)
Ohh, I see
Yea I get that
But that is not the coordinates right? The answer is supposed to be a vector
there is only one generator for H
so the vector is 1d
(ie just (t-4))
oh wait
does P3 mean polynomials of degree less than or equal to 3?
I believe equal
it wont be a subspace if its only equal
this is wrong
Then it is less, I translated it to english myself so might have been wrong there
and the basis is what you had here
ie t(t-4)(t+4) and (t-4)(t+4)
sorry for the confusion
No thats okay, I am just a bit confused in how I am supposed to write the answer. It wants them as the Polynomials in my choosen base
maybe write $t^3-4t^2-16t+64 = t(t-4)(t+4) -4(t-4)(t+4)$?
Toby
Toby
basically, the things you had here without the 'a's
and not a2 since that has degree 4 which is bigger than 3
np :D
Yea that i understood, if we were to use another polynomial we would get to high of a degree
Curiosity question, why dont we write a last polynomial as just t? Since we have t^3 in the first, t^2 in the second
because no degree one polynomial has two roots
ie, non zero line goes through both (-4,0) and (4,0)
Ohhh right!!! Since our base needs to contain (t-4)(t+4)
yup
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I'm not sure how to deal with the part after I factor r
I got to $r(cos\theta^2 - rsin\theta^2) + 14rsin\theta = 0
(put the eq in dollar signs)
how
Nim
am I suppose to factor inside the bracket?
like (x^2-y^2)(x^2+y^2) kinda stuff?
nvm i solved it
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How did we get rid of the denumerator?
rationalise by multiplying by the conjugate
yeah I get that
(a-b)(a+b)=a^2-b^2
simplify the denominator
(4+t)-(4-t) = ?
Yes you can see in this
what are you stuck on then?
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does anyone know how to solve this,
i think my answer is wrong
Looks right
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Does this just mean to replace x using -2 or 3 and have 2 answers
yes
Yes, 1 answer associated with p(-2) and one answer associated with p(3)
Wow insane camera
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prove A-(B int. C) = (A-B) U (A-C) analytically
<@&286206848099549185>
yeah
i hate these proof questions tbh
me too
"analytically"?
that just means mathematically other than using venn diagrams @stoic saddle
so, by element-chasing...?
To show both are equal, we can show both left and right are subsets
Let x ∈ A-(B∩C); then x∈A and x∉B∩C
x∈A and x∉B or x∈A and x∉C
x∈(A-B) or x∈(A-C) or it's union
can you explain this step a bit
If $x \in A - (B \cap C) \
x \in A$ and $x \notin (B \cap C) \ x \in A$ and $x \notin B$ or $x \in A$ and $x \notin C
\ x \in (A-B)$ or $x \in (A - C) \ \ x \in (A -B) \cup (A - C)$
3rd line can you elaborate a bit
A - (B int C) means
Set of elements that belongs to A but not to (B int C)
So either it belongs to A and doesnt to B or belongs to A or doesnt to C
ColdTee
thank you
why though that
I don't know but it is required i guess
does these arrows have a specific name and significance in maths that you used what do they stand for
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is this right?
Result:
20
nope check for option E
ok
All but one should be “trivial” to check, I’ll say…
k so A is true
B is true
yeah b is true
Really? Why?
Come back to c later, do the others
what about E
Is this testing if I know the properties?
of the fundamental theorem
ad rules
and
well 6*-2 is -12 but that's not what the answer is
it's not necessarily the answe4r
the only thing secured is additivity and subtraction
not multiplication
when you have the same integral
definite integral
not multiplication
that why?
That’s a good point, have you checked D and E yet? 
[of course you have for D, I answered you already on that, but forget that I did]
I know e is true
because that rule where you can flip
the signs
if you do that for both of them
it stays the same
I mean
It functions
properly
but yea
Thx for the help g
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What exactly is meant here by Rationalize the Numerator? Is it a typo with Symbolab?
or is Rationalize the correct term, when you combine two fractions into one?
I always thought Rationalize meant to remove sqrts
when you combine fractions with a common denominators, you get an irrational numerator. They suggest you rationalize the numerator
Why is it irrational to combine two fractions with common denominators?
when you combine the fractions, the numerator has a radical in it. making the numerator irrational.
meaning it has a radical in it
Hmmm, I have to think about this..
'rationalize' just means get rid of the radicals
1/2 + 2/2 = 3/2. These fractions have common denominators. Would it suggest 3/2 is irrational? Or am I misunderstanding?
The numerator when you combine the two fractions becomes 1-sqrt(t-1)
They wanted to get rid of the square root (aka rationalize) so they multiplied the conjugate (1+sqrt(t-1)) and then canceled t
no, it doesn't have a radical in it
Oh, I didn't pick up that part from this explanation
how would you word this to mention radicals?
is the idea "roots" are irrational? or powers too
like ^2 and ^1/2. only ^1/2 (sqrt) would be irrational?
yeah thats what I thought.. only when a radical can be drawn, is it considered irrational
this function has irrational numerator and denominator because it has radicals in the top and bottom
yeah
I often hear "rationalize the denominator", I think it depends on the question if you need to bother or not.. don't think professors are too picky with that
my line of thought, is that if it starts with a radical in the denominator i think it's OK to answer with that too
otherwise I will rationalize
but for this on Symbolab
it says "Rationalize numerator".. how is it being rationalized? It's just 1 in the numerator
I wrote it out if u want to see it
please 🙂
Oh I see, so we are getting a common denominator
^^^ there's a page of work you're skipping and then trying to understand what's happening
this is the same thing as "rationalizing"?
no it's OK, the steps are explained on Symbolab too. I am more concerned about the label "rationalize numerator", if that is considered a typo or not?
no
seems to be this is just find a common denominator, which would be different I think?
we aren't removing radical signs
yes you are
oh, for the numerator
yes. So you're rationalizing the numerator
So basically this
I missed this explanation
multiplying by the conjugate
to rationalize the numerator
Yeah so you can do the limit
i suppose we could have rationalized the denominator instead.. either way, same answer
oh wait, maybe not? for limit would I need to rationalize the numerator?
to see if I can cancel anything
there's a t multiplied onto the denominator, when you take the limit that could be a problem.
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not sure what i will be dividing/multiplying at the end to get my limit
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Hi
For all positive natural values of x find all integers N that in their decimal representation have x number of 2 in their digits and 1 time 5 in their digits and are a perfect square
It was in a math comp and I got 25 and 225 but I’m not sure if I’m correct
Yea but how do you prove for all x that these are the only sol
Might want to post this in #competition-math
Ye probably
But imma leave it here too
<@&286206848099549185>
So my reasoning was that for it to be a perfect square it can’t end in 2 so the 5 must be at the end
After that
When x>2 when you try to factorise N you get a number with x-2 8s and a 9 at the end
Which is a prime number most of the time so it can’t be factorised so N isn’t a perfect square
but it can also end in any other number than 5 and the 5 being in any other digit right?
No cause the number only has 2s and a 5
Which I asked and was verified by the overseer
Cause I had the same thought
But this number can be factorised if x+2 I think is a multiple of 4
As it can be divided by seven in that case
But if I’m not mistaken the number after that division always comes out prime s
Is there a flaw in my line of thought?
…
Any luck
Oh, then consider rewriting it as 2(10^(x+2)-1)/9+5=k^2
10^(x+2)=(9k^2-44)/2
k=2n
10^(x+2)=18n^2-22
kappa
Now we have to solve this Diophantine
Lemme try to
Thanks
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!15mins
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@still temple Has your question been resolved?
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Anyone?
@still temple Has your question been resolved?
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hello
i need some help finding the derivative of 4xsinxcosx
what have you tried
so i tried applying the product formula
and i got 4x * (cos(x)-sin(x)) + 4*(sin(x)cos(x))
would that be correct?
cos(x)-sin(x)?
how did you get that?
well bcz i thought d/dx of sin(x) is cos(x) and cos(x) is -sin(x)
product
yes
it's close
ohhh
my bad i did that too fast
ok so now i would apply the product rule again?
since theres a 4x?
you apply it twice
you do product rule on 4x and cos(x)sin(x)
and then product rule on cos(x)sin(x)
wait hold up
so product rule on the original and then product rule again?
is that because g(x) has a product within itself?
yes
so
rn i have 4x(cos^2x-sin^2x) + 4(cosxsinx)
and i apply the product rule to the second half again correct?
no, because you're not taking the derivative
so what should should i do now?
nothing, unless you want to simplify
in which case recall your double angle formula
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can someone help me figure out how where im supposed to find the standard dev?
It's a binomial distribution
okay thank you
im confused tho how would i implement that
You don't implement it
You follow the formulas for the binomial distribution
And plug in your parameters
Start by reading the binomial distribution
can you show me the first few steps im so in over my head with this class
@main idol
<@&286206848099549185>
@still temple Has your question been resolved?
Look these up
okay
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Help asap.
What are the bounds
for x: 0 and 4
for y: 0 and x^3
?
I got this but it's wrong. What did I do wrong?
Why asap
Switch them?
Yeah try that
You can’t do integrals with a different variable on the outside
Cuz you can’t solve it
Wdym
If you reverse order of integration
You switch the two
And you can do a integral with respect to y if one bound has x in it
It will leave x in the answer
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I am struggling with a tough combinatorics problem:
Find in how many ways a sequence of length n (containing only letters a, b, c, d, e, f, g, h, i) can be arranged, given the following rules:
- the sequence must start with either
a,b,c,dorg. - the sequence must end with either
a,b,c,fori. - after
a,b,c,fandi, there must be either ana,b,c,dorg(or the end of the sequence). - after
dande, there must be either aneorf. - after
gandh, there must be either ahori.
I have no idea how to even get started with this problem. I know the basics of combinatorics, such as factorials, permutations etc., but I still cannot solve this problem.
interesting
My dating standards are lower
@still temple when you say n letters, do you mean n letters, or the letters in those brackets
No they're lower 😔
The sequence's length is n.
But they can only contain the letters in those brackets?
Yes. The sequence only contains the letters in the brackets.
so you go (a|b|c)* then you maybe go (deeeeeef | ghhhhhhhi) and then you maybe start over
that's not very complex but how to count that
If by "start over" you mean going back to either a, b, c, d or g, yes.
This is a mad question
I think you need to get set theory involved with the venn diagrams
let's look at n=4
dfgi
gidf
def_
_def
ghi_
_ghi
ghhi
deef
_df_
_gi_
__gi
__df
gi__
df__
amazing
What do the underscores mean ?
Oh, okay.
also 4 underscores
and also gigi and dfdf
so you sorta fit any number of these df things, you can leave empty spots, and they can be any length but at least 2
that doesn't give me ideas how to count it
but it's still like, within reach sorta
I was thinking of creating a list of auxiliary sequences (let's name them f), representing how many choices we can make at a given point.
f(n) can only have five values
If f(n) = 3, it means that at position n, our sequence contains either a, b or c.
If f(n) = 1, it means that at position n, our sequence contains d.
If f(n) = 1', it means that at position n, our sequence contains g.
If f(n) = 2, it means that at position n, our sequence contains either e or f.
If f(n) = 2', it means that at position n, our sequence contains either h or i.
Now, given a length n, we can see how many of those auxiliary sequences we can build - then, for each sequence, we multiply all of its values, and then we add the results obtained from each sequence.
The reason I marked some numbers as prime is so that the sequences (1, 2, 2, 3) and (1', 2', 2', 3) count as different sequences, but when multiplying all terms, they count as the same numbers.
The advantage of this is that these auxiliary sequences have easier rules, and I assume that calculating the number of such sequences isn't as hard. However, I still can't calculate the number of these sequences either.
No, this is wrong. Sorry. Using underscores instead of a, b and c is still the easiest method.
i think i have an idea
Ok, I have another idea: I'll forget about g, h and i for now, and I'll focus only on sequences with underscores and d, e and f.
to any sequence you can append an underscore
a sequence ending with f/i can be extended, f becomes ef
and you can append a whole df to extend by 2
that should give a recurrence
Hmmm, I'm not sure I understand.
it's like your idea i think
different sequences based on what's last
in the end we will ad them up
you pretty much understand
cuz i haven't made it work yet
Correction: f(n) can only have three values:
- 3 means that it has
a,borc. - 1 means that it has
d,e, orf(it counts as only one choice, because whether it isd,eorfdepends on the position on the chain). - 1' is the same as 1 except it is for
g,handi.
Nu(n) = 3 (Nu(n−1) + Nf(n−1) + Ni(n−1))
Nf(n) = Nf(n−1) + Nu(n−2) + Nf(n−2) + Ni(n−2)
Ni(n) = Ni(n−1) + Nu(n−2) + Nf(n−2) + Ni(n−2)
that's it
It's wrong to count the e and f as two choices, because which is which is already determined by the auxiliary sequence. This is why I got rid of the f(n) = 2 and f(n) = 2'.
Hmmmm.
What does that n argument mean ?
the length
Oh, Nu(n) means the number of ways a sequence which ends in underscore can be arranged ?
yes
no idea how to even proceed
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I need help with breaking down a statistics problem. The first question is asking what is the probability of the sampled households directly affected are greater than 8
Per my notes, I'm supposed to find the (x(bar) - mean)/(SD*(sqrt(N))
I know N is supposed to be Sample size (25) but I dont know the mean and SD, in which I think I may be using the wrong formula for this one
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.close
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Could use a hand with question. I think I'm supposed to parameterize, but I haven't really learnt how. I think I learn best through examples so solving this would help a lot! Here's my attempt without parameterization: (I believe 0<x<sqrt(72) and -6<y<6 are the appropriate limits?)
general advice, dont upload random files
(discord doesnt like heic images, use png instead)
@wispy garnet Has your question been resolved?
any <@&286206848099549185> out there who aren't as dead in the water as i am? :p
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@wispy garnet Has your question been resolved?
Same case for me been waiting for hours
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i dont understand where the 1 + (n+1) - 3 comes from
this is a recursion proof: in blue is the n gon so it has n(n-3)/2 diagonals
in pink and black are the added diagonals
when you consider the extra vertex
@quaint arrow Has your question been resolved?
i still dont really understand
they consider a n+1 convex gon
pick a vertex
and say that the remaining n vertices
form a n convex gon
by induction
this has n(n-3) diagonals
then they count how many diagonals arre added when you add the vertex back
okay wait, can we just use a pentagon for analogy purposes please?
yeah ok
so if i pick the tip, there are 4 remaining vertices
yep
im just hoping an analogy with a pentagon will let me understand where the 1 + (n+1) - 3 comes from
the pink ones are the diagonals that start at the picked vertex
so now im i forgetting about that top vertex and im a really only looking at a square?
this is how induction works
oh okay
the square has 4(4-3)/2 diagonals
but now how many are added if you consider the 5th vertex
3 more
so by adding 2 extra sides, we get 3 more diagonals
right?
or 1 extra vertex = 3 more diagonals
its true for the pentagon
but probazbly it depends on n
and thats why we do it on the general case
to not do each case
right, but for the pentagon, is it 1(1-3)/2, which is -1, + 4?
oh wait it's not linear
that won't work
wdym?
this doesnt make sense iml not in your head
i was saying if we plug in 1 (since 1 extra vertex) into the formula, we get 1(1-3)/2
But im guessing that this calculation is meaningless
why would you do this calculation?
just try it in the general case
if you add one vertex to an n gon
how many diagonals are added?
theres one for the two adjacent vertices
that were adjacent to each other before
but arent anymore
is it n-2?
why?
since it can touch all the vertices besides the 2 it's adjacent with
yeah right
but dont forget the last one
between the two neighbours
those are the pink ones
this is the black one
ohhhh. Thank you so much. I understand it now
then its just calculating
Right. I really appreciate you walking me through the problem. Thanks a million!
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where are you stuck?
tangent = what over what?
ok, which side is opposite
and which side is adjacent
no..
34 is the hypotenuse
the missing side
what theorem tells you how the sides of a right triangle are related?
yep
try using that
how did you get that
it can't be longer than 34
the hypotenuse is the longest of the three sides
no..
suppose you call the unknown side Y
then you have Y^2 + 30^2 = 34^2 right?
solve that for Y
where are you getting 2056 in the first place
can you show me what you did
you don't add them
Y^2 + 30^2 = 34^2
how do you get Y^2 isolated on one side?
yea
that's Y^2
so how do you get Y from that
yep
well which one?
ah right
16 for Y
then the tangent is opp/adj
you sure you're checking the answer for the right problem?
wait one moment
which one is opp and which one is adj?
you want opp/adj
opp is 30
adj is 16
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i forgot to write my work
but i tried it again with 315 and i got something else
154/2
77cos(315)=54.44
77-54.44=22.56
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You can construct a triangle to find out $h = 80 - 77 \cos \theta.$
Shao
@rotund yacht Has your question been resolved?
where did u get 80 from
ahh
Diameter is 154, so the radius is 77
Yuppp
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hey
oh oops
lol
@oak void Has your question been resolved?
wb the range of y?
(0 to +infinity)
\
^
o to +infinity
1/4 is not zero
sec function cannot be less than 1 ..
what?
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Could use a small bit of help. Given is a countable partition {A_i}_{i in N} in X. Also given is the sigma-algebra F which just consists of every possible countable union of A_i. How can I show that if B is in F that the complement is too? Any hints would be appreciated. I did try looking into applying DeMorgens law but that just gives me an intersection of complements and I am not sure that's helpful for anything
can you give me the definition of a sigma-algebra
3 properties. the sigma algebra contains the whole set. If an element B is in the sigma algebra then so is the complement of B and finally taking an union of a countable subset of the sigma algebra is in the sigma algebra
so what is there to really show?
you do just use demorgans law
and then use the definition.
Right except the fact that the sigma algebra contains countable unions?
Taking demorgans law gives me intersections
when you say every possible countable union, hopefully you also include finite unions, yes?


