#help-23
1 messages · Page 92 of 1
I just wanted to solve this equation using subtitution method:
x^2-4x+y^2=0
x-y=1
so i did like this: x = y+1
(y+1)^2-4(y+1)+y^2=0
2y^2-2y-3=0 from there i dont know what to do
We were almost done.
2y^2-2y-3=0
And this
(y-1/2)^2 = 7/4
are the same
we only needed to square root both sides
sqrt((y-1/2)^2) = sqrt(7/4)
|y-1/2| = sqrt(7)/2
y-1/2==Sqrt[7]/2 or y-1/2==-(Sqrt[7]/2)
what do u mean by |y-1/2|
So y = (1 + sqrt(7)) / 2
or y = (1 - sqrt(7)) / 2
what the hell
There is another way like using delta
in answer it says When x = 0 y = -1; x=1 y=0
You should read the whole process from here #help-23 message
I am talking about your initial equation
Which is what we were doing the whole time.
Have you guys tried using delta
what is delta?
Muta, you have to check the basics again.
Delta id calculated with
b^2-4ac
Then if delta<0 there is no solution
If delta=0 there is one solution
And if delta>0 then there is multiple solution
You can't solve 2nd degree equations if you have not studied them
Yes
i tried i got D = 28
but its wrong because i cant do sqrt(28) :/
but its not whole number like answer is in whole number form
but that's not because of the equation you gave me
Then you follow another formula after that
y1=-b+sqrt(b)/2a
y2=-b-sqrt(b)/2a
anyways, i'm checking it and that's an error
x = 0 y = -1; x=1 y=0 This is not the answer
Where did you get that from?
exercise book
the book is wrong, or you copied it bad
x^2-4x+y^2=0; x-y=1
For this system of equations you can clearly see that your solutions are wrong
The book is right lmao
by replacing them in the equations
I said either the book is wrong or the exercise is not written correctly here
x=3/2-Sqrt(7)/2, y=1/2-Sqrt(7)/2
x=3/2+Sqrt(7)/2, y=1/2+Sqrt(7)/2
These are the solutions for his system of equations
I scrolled up a bit, there is a lot
not related
we were solving 1 single equation
then he said it came from a system of equations
x^2-4x+y^2=0; x-y=1 this one
x^2-4x+y^2=0
x-y=1
When x = 0 y = -1 ; x = 1 y = 0
lol
its written in a book :/
totally out of context
Yes
They just asked you to find solution where x and y give 0 with the equation
You just have to determine a value to one of these and resolve
no they asked to solve
????
this is written in the back of book of answers
What does solve means to you?
I understand now
so in yout book of answers
they put this system x^2-4x+y^2=0; x-y=1
and they say the answers are 0, -1, 1 and 0?
i don't think it says that but
if that's what they say
the book is wrong
:/
can u take a picture
or better
can you read the exercise without solution?
i mean, in the book of questions
not the solution
Its very confuse
you can check yourself
When x = 0, y = -1
x^2-4x+y^2=0
0^2-4(0)+(-1)^2=0
1=0
wrong
as you can see, either the book is wrong, or you are not reading it properly
Ok here is word by word:```System of equations:
x^2-4x+y^2=0
x-y=1
The number of solutions is
A. 0
B. 1
C. 2
D. No soliution```
lol
so, you solve it, you get this
x=3/2-Sqrt(7)/2, y=1/2-Sqrt(7)/2
x=3/2+Sqrt(7)/2, y=1/2+Sqrt(7)/2
and you answer
C) 2
if the book is saying other thing, it's wrong, probably a typo or talking baout other exercise
but why it says in answers when x = 0 y = -1
because books are made by humans, and they can get confused
propably talking about other exercise
nah this book is revised in printing there are no mistakes
As I told you before.
- The book is wrong
or - You're not reading correctly.
The system of equations you gave me have the solutions I provided
Period
- I still dont undearstand how to solve this
Then, read the whole explanation I gave before again until you understand it.
i dont undearstand pizzas
random numbers popping
i dont know what to do
nah f this i cant spend more than hour
Thank you for your patience and explanations you provided
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In how many ways can we arrange the letters murmur, such that no two alike letters are together?
Ive been trying to solve this for the past hour..
Draw a Venn diagram
MY MIND IS LAGGING RN
I don't blame you
I've solved something similar before
It's pretty hard for the first time
4 ways?
Tried that it didn’t work
Yes.
Three bubbles
Bro ive seen smthn similar on quora
that's objectively the best way to do this
Rip
1.rmumur
2.rmrumu
3.rumrmu
4.rumurm
U can start with m or u
Its gonna give u more than that
I dont think it can be solved like that i got lost while doing it
There are 30 ways
Uh idts
Pleaseee show me how
damn
I appreciate the effort man
First, tell me how many ways to rearrange them.
90
ok
u have laready something done?
can i see all your job?
or u're just too fasT?
xD
I tried counting two letters as one
But then didn’t know how to know the repetition of the rest
30
usually, when someone ask you for something, u look the opposite
Yea thats what ive tried ig
The arrangements Where RR exists
why number 30 exactly?
I tried multiplying that by 3
so u have 30 for MM, 30 for RR, 30 for UU
But then i should know when did the letters appear twice right?
Yup
how many for MU together?
right, so how much?
Lemme count that
oh yeah hes right
5!/2! ?
why 5?
urmurm
umrurm
umurmr
murumr
urmrum
rumurm
rmurmu
mrmuru
rmumru
umrumr
rumrmu
rmurum
urumrm
umrmru
mrumru
mrumur
mururm
rumrum
umrmur
urmumr
mrurmu
murmru
rumumr
mrurum
murmur
rmrumu
rurmum
urmrmu
rmumur```
Considering MU one letter
Damn
lol
sry, i don't want to spit the answer, but the last thing u said is wrong
is not 5!/2!
mine too lol
it's fine, i already know how to do it
wait so its not 30???
it is
good
sry i think i asked the wrong question
Its fine go on
give me 1 second, i'm trying to find the good question
it is 4!/2!, i'm just exhausted
and can't find the way to ask u
i just did it by hand
these ones
are the ways to arrange the letters so that both
for example RU are kept together
but remember that you have to substract this from the ways to rearrange 3 letters
like RUM
which is
3! right?
Hold on lemme process that
Oh okay
So ways to keep two different letters-the ways to keep 3 diff letters right?
Youre nottt go on
ok we finish with this solution
so it would be
90-30-30-30
that's 0
12+12+12 36
-6 = 30
but i have a better solution for this problem
we are gonna make this
MU _ _ _ _
now the next letter is an R that can be here
Okay
Okay
There are three possible ways to choose the first letter of the word, and two possible ways to choose the second letter.
So the number of ways would be 3 * 2 * 5
which would be 30
But why is the second one 1
this is only possible because the letters repeated wice
let me re-check
sry it's 2! for the second
and 1 for the third
i said wrong
Oh yah it makes sense now
So for each pair of alike letters, calculate the number of permutations where those two letters are adjacent, then subtract the sum of all these values from the total number of permutations to get the final result, in your case the word murmur, there are 90 total permutations without any rules set, so there are 3 pairs of alike letters: mm, rr, and uu, following that each pair has 30 permutations where they are adjacent. So, the final result is 90 - 3*30 = 0.
yes
Wait imma try to understand this as well
Omg tysffmmmmmm
damn
you're welcome
I respect your dedication
somehow inclusion exclusion principle is more easily undearstandable than my systems of equation
xd
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yeah post work homie
^
Gotcha, take your time for it to be legible. Also, symbolab is super helpful for finding the specific substitution sometimes for a quick check.
could i do it like : tan^2 (x) + 1 = sec^2 (x)
so that would make the integral of sec^2 (theta) - 1
which equals tan(theta) - theta ?
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Linear Algebra help
they did the row reduction on [A | 0]
that's the first column after the | in the matrix
The row reduction on [A|0] is just this:?
yes
and the the [4 8] is the next column, and [-2 -4] is the third column
How did they get this?
So converting it back to an equation gives you x + 2y = 0, and x = -2y
There aren't any free variables so how it there a T?
so your vector [x y] is [-2y y] = [-2 1]y
or t, doesn't matter what you call the variable
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why is there a flat line between 1/2 and 8?
when i try to remove the root and the power it gives a differen't function and im not sure why
$\sqrt{a^2}=|a|$
Toby
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what is wrong with my answer?
The above is my solution, anything wrong?
btw, I also tried replacing them with u and v, which is also not right
sorry I can't really follow your work
so z_x basically means dz/dx
did you get dz/dx = e^y, dz/dy = (y+1)e^y + xe^y?
yes it should
now I got the second one right
what did you get for dx/du and dy/du?
got it all right now, thanks man!
just gotta replace all of them with u and v
so pain
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For part b, how is gH the set of left cosets
In the question it refers to create a bijection between the set of left cosets and Y
the symbol $\mapsto$ means "maps to"
Toby
which means gH gets mapped to g(a)
the set of all possible gH is the set of all left cosets
Isn’t this a bijection from a singular left coset to Y though?
no, in this context, it defines a function on all possible cosets gH for any g in G
I see, for the final statement can I just say by lagrange’s theorem |G|/|H|=number of left cosets =|Y|
yes
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How does this prove the existence of i such that p^i(x) =x?
Is the contradiction literally just the fact that they have found that i = k-j+1?
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Why can't I do this?
Because lim(cos(x) + x^3 sin(1/x)) does not exist
So when one of the two limits does not exist alone, I can't use the property of limit multiplication to separate the limit.
Exactly
Ok, thanks.
However, now that I remember it, in the case that one of them is 0 you don't need the other one to exist, it is enough if it is bounded
But in this case the second one goes to infinity
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How do I graph y=-2^(x-3) without an ordered pair?
I mean without making a list of when x=1, y=...
Js there a way to graph this by just looking at the numbers like you would on an graph of y=-(x+3)^3
hmmmm well we can probably tell a few things without making a list
like for example
any number raised to the 0th power is equal to 1
so looking at -2^(x-3)
we can see this will be raised to the 0 at x=3
and that would give y=1
Thanks, how would I find two other points?
I actually need to correct myself first
this equation is actually (-1)*(2)^(x-3)
so at x=3, we get (-1)*(2)^(0)
which is actually -1
not 1
Does that make sense?
We can try to find the y-intercept too
that would be nice
that's when x=0
-(2)^(-3)
AustinU
so that would be the y-intercept
hmmm maybe
AustinU
AustinU
I have another question
f(x) = -2f(-2x-6)-3. Is the correct equation [-1/2x-6, -2y-3]?
I won't help with another question until you respond to my help with your last one :p.... but anyways I'd need more info for that one
does it get close to it?
Sry, I was typing it
no worries!
Yeah it does bc as the x value increases, the fraction is smaller
Could you help with this one?
send the original question please
I'd put in the chat here what your confusions are about this one, and someone else will come along and help out
Wdym?
describe what you need help with about this question
I think i did it right but comparing it with someone else's answer it's not correct
Actually, I found my mistake
When factoring at the beginning, I forgot to factor the 2 out of the 6
Thanks for the help!
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I'm a little confused by the notation of Stirling numbers of first kind
In this example, what is n and k?
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@junior wagon Has your question been resolved?
I have no idea what the stirling numbers are but n and k are just numbers
i dont understand why you are confused
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y'(x) = x, y(0)=y(1)= 0
I know this ODE can be solved using Green's Functions and I already did
But the question asks for the verification
... are you sure you wrote it correctly
So, how to do it normally?
as written, the equation has no solution
I get your concern, that is also what is bugging me
I got the Green's Functions and intergrating it gives me
probably
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how do you know that cost = -cost is the same as pi/2, and 3pi/2
i have a unit circle and i see that this is when both cos are = 0
So you are trying to find when cos(t) is equal to -cos(t)
AustinU
whattt ahhhaahah noooo
that can't be!
so obviously something went wrong when you divided by cos(t)
what could it have been, to stop you from being able to divide by it?
well, if cos(t)=0 then you can't divide by it
that would be dividing by 0
which you can't do
So it is clear that this equation is only true when cos(t)=0
and that is your new problem to solve
using your unit circle you should see that the two angles that satisfy that are pi/2 and 3pi/2 (within 0 to 2pi)
Does that make sense?
one sec just processing this lol
so are you saying that you cannot mulitply by reciprocal then distrubute the -1?
AustinU
So the error must have occured when you divide by cos(t) as that is literally the only step that we took to produce this false statement
so from that you can see that cos(t) must equal 0, and that is why the error arises
Does that soothe your mind?
@lean otter Has your question been resolved?
i think i get it but thats mind twisting honestly
since you would not be able to divide by cos only if it were equal to 0
and cos is equal to 0 at those two points listed in the answer
yes
thats crazy no way im coming up with that on the test
well thank you again
Well, I was just trying to reason it out for you
the explanation can be much simpler
so don't pysch yourself out
when does negative (number) equal positive (number)
?
never
well
yea
when that number is 0
so that's the main idea
is - cos(t) = positive cos (t)
then cos(t) is 0
oh i get it more now
since zero isnt postive or negative
yeah, negative 0 equals positive 0
although that really doesn't mean much
just it isn't true for anything other than 0
bro thatz crazy
so that is what is useful
ay good helping man
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If f(x) = g(x-1) and g(x) = √(x+1), find f(4)
!status
What step are you on?
1. I don't know where to begin
2. I have begun but got stuck midway
3. I got an answer but I'm told it's wrong
4. I got an answer and would like my work checked
5. I have a question about someone else's worked solution
6. None of the above
f(x) = g(x - 1)
what happens when you replace x with 4 in this equation?
g(4-1)
f(4) = g(4-1).
or, f(4) = g(3).
are you now able to calculate g(3) and hence also f(4)?
Yes, thank you
-2f(-1/2x) is the transformation applied to √x. Would I have √(-2x) or √(-1/2x) under the radical?
Can you explain why? I thought when I do 1/b the number would be flipped
??
what's "1/b"?
i am simply showing you what happens on a purely symbolic level when you evaluate -2 f(-x/2) for f(x) = sqrt(x).
your question was purely symbolic in nature and so is my answer to it.
y=f(bx) and there is a horizontal compression by 1/b or stretch by 1/b if 0<b<1 on a graph
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Injective, Surjective, Bijective, for functions in the complex plane
yes
but well now you can take roots of negative numbers and stuff
so results may vary
a function that may have been injective over R might now not be anymore
same for surjective
so how would i work out this specific example?
well what would you do over R
ngl i've just been graphing and then seeing what they are
im struggling to graph this tho
hmm
ok so:
for the function f(z) with complex numbers z_1 and z_2, equating f(z1) and f(z2) gives the same images
so therefore they can't be injective
how do i test for surjective
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how do I show convergence of the sequence:
$\Bigg\{\frac{\log_b(n)}{n}\Bigg\}, b>1$
steamhahasteamhaha
I have no idea where to start
I was thinking maybe squeeze theorem
but I don't know how exactly
I don't know how to "bound"
$\log_b(n)$
steamhahasteamhaha
a variety of ways exist
do you want the from-scratch version or a more refined version
i wanna do refined version first
$\ln(n) \leq \frac{1}{p} n^p$
Ann
for any positive constant p
for your purposes, any value of p less than 1 fits; if you're buridan's ass, take p = 1/2
and of course, log_b(n) = ln(n)/ln(b) so we might as well take the base as e
hmmmm
do you need me to clarify anything else or are you going to continue
(don't answer "yes" to this one)
what about the from scratch version
$\ln(n) < n$
Ann
whence the one for n^p is derived by some trickery
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Let m be an integer, let X_m = {p = n^2 + m^2 | n is a natural number} be the set of primes of the form n^2 + m^2. Prove that the Dirichlet density of X_m is 0 for each fixed m.
No one ever posts in those I asked a question and it got ignored for 2 days
@sand ember Has your question been resolved?
I know that usually due to Fermat we have that p = x^2 + y^2 iff p = 1 (mod 4), but that seems different to here
@sand ember Has your question been resolved?
@sand ember Has your question been resolved?
<@&286206848099549185>
You're more likely to get an answer in those channels
I got an answer in them recently
Again I have not learnt anything about Dirichlet density but it seems like It would be worth noting that the sum of X_m is 2* all primes congruent to 1 mod 4
So maybe you could say something about the density of X_m vs X_n for m not equal n and deduce that they're 0 by considering the sum of densities or something
I've asked it but I'm keeping this open for now in case someone can help me with it
I know this, but this seems different
I mean the union of X_m is the set of such primes
If I'm understanding you right, you think I should do the union. We do have that if X_i intersection X_j is the empty set then dens(X_i u X_j) = dens(X_i) + dens(X_j), but we don't have that they're empty, e.g. 5 is in X_1 and X_2
So I don't think I can break it up like this
yeah but it's like twice the density
or maybe not
there may be something to consider in the number of ways a prime can be written as a sum of two squares
Idk if this is going to be the way, I think it'll have to do with fermat's theorem of the sum of two squares, but I don't why it wouldn't hold here
I guess we could look at the specific formula
The dirichlet density is going to be $$lim_{s\rightarrow 1^+} \frac{(\frac{1}{m^2 + 1})^s + (\frac{1}{m^2 + 2})^s + ...}{log(\frac{1}{s-1})}$$
LeftySam
Note here the top should be the primes of that form that is being summed over, so for instance if m = 1, then m^2 + 3 isn't a prime so that isn't summed over. In addition, m is fixed
@sand ember Has your question been resolved?
@sand ember Has your question been resolved?
@sand ember Has your question been resolved?
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Need help
After differentiating siny=tanx implicitly and getting cosy dy/dx = sec^2x I don’t know the directory to take
Or if it’s even the right one
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how should i set this problem up?
what would you guess?
i feel like something has to = 81
yes..
What have you tried?
im not sure where to start, if i dont have momentum from the beginning ill just be confused
when the diver hits the water, how far has he fallen
81
81 feet, correct.
you have a function that gives the distance fallen by the diver in terms of time
now you need to put the two together
81/16 ?
81/16 equals what
5.0625
then sqrt?
no, I meant the equation you're working with
81/16 = t^2
good
"I started with the equation 81 = 16t^2 and divided both sides by 16."
yes
you should make it a habit to put everything you do into words.
anyway, continue.
you now have t^2 = 81/16.
your goal is to solve for t.
keep going.
don't turn it into a decimal number...
why not?
decimals, in general, are ugly.
and for fractions whose denominators aren't powers of ten or divisors thereof, also imprecise.
and you can lose precision
that, or you'll have to always write 0.124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857124857... whenever you want to talk about the number one-seventh.
you might be under the impression that fractions are less "numbery" than decimals. let go of such bias.
ya thats it
is that a thing?
sure is.
except for when they are clean numbers
ok, cool, yes, you know this.
now read (and perhaps type out here) the second question.
With what velocity (in ft/s) does the diver hit the water?
velocity is related to d(t)
we go 81 ft in 2.25 seconds
and i think velocity is distance over time
but 81 / 2.25 = 36
and that is incorrect
you are wrong, but in fairness i did kind of not give many pointers in the right direction
you want the velocity of the diver at the instant he hits the water.
does this clarify what is being asked for?
81/2.25 would give you the average velocity of the diver over the course of his fall.
which is not the same thing as his instantaneous velocity at the moment of impact.
you understand the difference between these two, do you not?
.
do we use the average velocity of 36ft/s ??
somehow
i think multiply something with 81 or 2.25
i have no idea what or why tho
<@&286206848099549185>
i do not know
velocity = distance / time
we cant get derivative of a normal number like 81 or 2.25
its 0
im not sure what ur getting at
ok
but thats 0
??
i did not say the derivative of 2.25
i said the derivative of d, evaluated at t=2.25
try to be a little less oblivious to the problem statement.
i've seen that a lot. you go into a problem and not more than 4 steps in you forget any and all details from the outset.
this the momentum i was talking about
like jumping to rocks in the water, if i miss a beat , im lost
we're looking for the velocity at the 2.25'th second
"2.25'th second" is a bit cringe as far as wording goes.
ok
you're not interested in a one-second interval, you're interested in an instant. a point in time.
instantaneous velocity
ok...
The distance the diver falls in t seconds is given by the function
d(t) = 16t^2 ft.
d(2.25) = 16(2.25)^2
?
oh the function
i am using notation consistent with the problem.
d'(2.25) = 16(2.25)^2
no
you're confusing d' with d
you've done things with derivatives before, haven't you?
yes
ok then
given that i've been talking about the derivative of d(t) incessantly all this time,
was this not cue enough for you to work out d'(t)?
no, bad, bad
d(t) = 16t^2 is the definition of the function itself. d(t) = 81 is an equation we needed to solve for the previous part.
indeed
we differentiate 16(t)^2
to get 32t
then 32(2.25)
wow
it would have helped to know that instantaneous velocity = derivative of velocity function
yeah, you're supposed to know that.
er,
no
instantaneous velocity = derivative of POSITION function
the derivative of velocity is acceleration.
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Hi, I’m looking for help with writing a mathematical formula to calculate probability involving dice rolls. It’s for a tabletop RPG I’m going to be playing.
What I need this formula to be able to do is:
• Calculate the chance of rolling a double at least on X amount of 6 sided dice (by “at least” I mean that triples, quadruples, etc count as rolling a double)
• Double 6 needs to be excluded (it counts as a failure)
• The face number (not the total of the double) is greater than or equal to a number between 1 and 5
Any explanation for how said formula works would be appreciated!
@young mantle Has your question been resolved?
The chance of rolling a double a better is the inverse of the chance of rolling all singles
If X>6, then there is a 100% chance of rolling a double or higher
Right, but double 6 is to be excluded as a success (this is to stop players from getting a 100% chance to succeed with 7 or more dice)
So success is double or better of 1-5, and everything else is failure
Correct
So we can write failure as rolling zero or one of all 1-5
X=0 and X=1 are trivial at 100% failure (so 0% success)
Right
X=2 failure, we consider two cases:
Case 1: first dice is 1-5, then second dice can be any value except matching the first, so there are 5 choices for the second dice.
Case 2: if first dice is 6, then second dice can be anything.
Yes
Number of outcomes in these two cases is 5*5+1*6=31
So probability of failure of 31/36, and success is 5/36 (which matches the naive way of considering 5 possible doubles)
Right, makes sense
X=3 is when things start to get a little more tricky
Probably where you are stuck too
Most likely
Kinda do the same thing, just more tedious.
Case 1: First dice is 1-5 (5 outcomes)
Case 1.1: Second dice is any non match 1-5 (4 outcomes)
Case 1.1.1: Third dice is any of the remaining 4 values (4 outcomes)
Case 1.2: Second dice is 6 (1 outcome)
Case 1.2.1: Third dice is any non match of first dice (5 outcomes)
Case 2: Second dice is 6 (1 outcome)
Case 2.1: Second dice is 1-5 (5 outcomes)
Case 2.1.1: Third dice is any non match of the second dice (5 outcomes)
Case 2.2: Second dice is 6 (1 outcome)
Case 2.2.1: Third dice is anything (6 outcomes)
Then just combine all the outcomes
5*(4*4+1*5)+1*(5*5+1*6)
,w 5*(44+15)+1*(55+16)
probability of failure is 136/6³
Tedium remains until X>6, then it's just probability of successive 6
There may be a better way to do this, but that's the best I got
This has been very helpful, thanks.
So once I get to 7 dice, does the probability of failure become the same as (probability for 6 dice + the inverse of probability of successive 6s) / 6 ^ 7 ?
Hmm.. hard to say now. I never was that great with stats. Maybe other <@&286206848099549185> are
That’s fine, it’s quite the complex problem and I’m not the best at probability as it is
if this is for a practical thing, maybe it would be easier to do it numerically via monte carlo
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no
it would be log ((9-x^2)^2)
the goal is to turn it into one logarithm
right side is okay
okay perfect
so its just log(((9-x^2)^2)/((3+x)(3-x)))
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what are we seeing here
angle?
the symbol above 180?
Yes
erm the symbol for measured angle
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so i need help i know i need to use that equation to just plug in the years but the correct answer isn’t popping up
well i just did p(1)=12,520e^0.058(1)
Good, and what did u get
12,551.05179776
Hmm
Gotcha
Yea just show me and I’ll see
Try just typing in exactly this: 12520 • e^0.058

That’s what I got as well

what would i plug in for c?
So it’s asking u for the amount after 2 years right?
yes
So what does ‘t’ represent
time
So what would t be for us in this scenario
Oh that’s what u meant
Doubling time means the amount of time it takes for us to get to double our original balance
So how do u think we could do that
Well what would double our original balance be
would the og balance b e after 1 yr?
it means when we start at t=0
Which is?
25040
So set 25040 = P(t) and solve
Nice job
so rounded would be 12.0?
Ye
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Np
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I'm pretty sure you are supposed to multiply your result by 2 because you shaded half of the region because there is two values of y for the same x
@native pagoda Has your question been resolved?
so your bounds for theta should've been -pi/2 to pi/2
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pog
how so
wait why is it -Pi/2 and Pi/2
Integration in polar coordinates
Instructor: David Jordan
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I just follow this guy method
11:47
he only shaded the x boundary
0=<x=<2
look at the given y bounds it shows a positive semi circle in quadrant 1 and 2 and a negative semi circle in quadrants 3 and 4. but you are given x =0 to x =2 which is only the right side of those regions put together which would be -pi/2 to pi/2 in theta. The person in the video wasn't doing a problem with the same type of bounds as you. You can tell by the graph he made and the region he shaded.
in the video he was looking at the area between y=x^2 and y=x which starts from theta = 0 to theta = pi/4. He got pi/4 because the top is y=x which is a line that is 45 deg above x axis which would be theta = pi/4. He got 0 because the functions intersect at the origin which is on the x axis and that's theta = 0.
I see
oh yeah fact bro
I have to shade
the lower part too
have to account for the y-boundary too
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!status
What step are you on?
1. I don't know where to begin
2. I have begun but got stuck midway
3. I got an answer but I'm told it's wrong
4. I got an answer and would like my work checked
5. I have a question about someone else's worked solution
6. None of the above
1
Ok
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Does anyone know how to solve this?
(\tan (\pi )/(15)+\tan (4\pi )/(15))
(1-\tan (\pi )/(15)\tan (4\pi )/(15))
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i got it lol
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Can someone explain what the hell homogeneous means
just google it
So you know what it means?
i know in chemistry not inmaths
chatGPT
google Bard
both will give you a more thorough explanation
I know in biology
what is homogeneous in bio
In mathematics, the term "homogeneous" refers to a property of a mathematical object or equation. A mathematical object is said to be homogeneous if it exhibits symmetry under scaling, i.e., if multiplying its values by a constant results in an object that is identical to the original object.
In the context of equations, a homogeneous equation is an equation in which all the terms have the same degree or order. In other words, the equation is homogeneous if each term can be expressed as a constant times a function raised to a power. For example, the equation:
ax^2 + bxy + cy^2 = 0
is homogeneous of degree 2, since each term can be expressed as a constant times a function of degree 2 (x^2, xy, and y^2, respectively).
Homogeneous equations and functions have many important applications in mathematics, particularly in areas such as linear algebra, differential equations, and geometry. In linear algebra, for example, homogeneous linear equations can be used to study the properties of vector spaces and linear transformations, while homogeneous differential equations arise frequently in the study of physical systems that exhibit scale-invariance.
there you go
GPT 
ya
@peak depot Has your question been resolved?
This doesnt explain why a first order ode dy/dx=f(x,y) is homogeneous if you can express f(x,y) as f(y/x)
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hi, can someone help me with this
Do you know about derivatives?
yea
Did you find <= 1 ?
Notice that x^r <= x for all x in [0, 1]
(btw, another proof would be using the binomial theorem, but that would be much longer)
wait is it possible to prove the edge cases then treat everything inside as if it works>
like case for x = 0 and x = 1
They're not special in any way