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if x is a positive number then the absolute value sign doesnt matter
does that make sense
Vѳrtєx-
you cant combine them like that
oh
because -12>|x| is not correct
you have to write it as two separate inequalities
statement
OKAY
=
oops my fault
and <= sorry
well let's take this for example
you cant have a number be >4 and <-4
so this is an OR statement
x can either be >4 OR <-4
yes sir
IT WOULD BE A AND????
yea
more or less
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Correct
youre on desmos, just write what they give you
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Is this legal
Jus wanna know
Yeah! This is called differentiating under the integral/Leibniz rule. You can read more here https://brilliant.org/wiki/differentiate-through-the-integral/
Differentiation under the integral sign is an operation in calculus used to evaluate certain integrals. Under fairly loose conditions on the function being integrated, differentiation under the integral sign allows one to interchange the order of integration and differentiation. In its simplest form, called the Leibniz integral rule, differentia...
They have an example thats almost identical to this problem as well
Ok thanks
Jus wanted to know if its possible by adding the alpha parameter as an exponent
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hello, I'm taking differential equations and it has been a while since I've taken Calc 3 and done stuff with partial derivatives. can someone explain how they arrived at $\frac{\delta}{\delta y}(1-\sin x)...$
PolloTundra | Aidan B
are you asking why they took the partial derivative?
or why the partial derivative of (1 - ysinx) wrt y is -sinx?
why the partial derivative of (1 - ysinx) wrt y is -sinx?
when you take the partial derivative of a multivariable function with respect to just one of the variables, you hold all other variables constant
so in this case, 1 - ysinx is a function of both x and y
and so since you're diff wrt y, you'd consider x to be constant when differentiating
clearly 1 is already constant so its derivative is 0
now when differentiating -ysinx, it looks like something you might want to product rule
but since you're doing it wrt y, x is constant, so sinx is a constant
so technically -ysinx is no different than something like -2y
and you know the derivative of that is just -2
similarly, d/dy (-ysinx) = -sinx
gotcha, so why is it the partial derivative wrt y when it's dx and vice versa?
that has more to do with the properties satisfied by exact differential equations
if you have a differential equation
Mdx + Ndy = 0
then it must satisfy d/dy(M) = d/dx(N) to be exact
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Im having a stroke reading this question
Is it possible you can explain what is being asked
And how a cubic function is associated with a 3D shape
so you start with a square
then you take out square corners, so you end up with a smaller square and flaps
you can fold those flaps up into a box shape without a lid
Ok i get that part so far
So perfect square for each cut out
yes
Alr
so then you fold it to be x high
the base lengths you solve for
and you get a cubic
How do you get a cubic
Isnt a cubic function not straight
Also wouldn't the answer automatically be A or C since they have the least amount cut out for the corner cubes
I dont get how the cubic function or less than whatever crap relates
Pls ping when you reply, im typing on my phone, so i gotta get back to work
<@&286206848099549185>
Bruh
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Sketch the graph of f by hand and use your sketch to find the absolute and local maximum and minimum values of f.
f(x) = 1/x, 1 < x < 3
yes
you need to find the critical points
how do you get the derivative of 1/x?
1/x = x^-1
And just use the power rule
yep
ok so like th eupper half of it then
but what should i do now , get the critical nimbers by making f'(x) = 0?
yep
so $-x^{-2} = 0$ ?
wakamole
yes
well thats just 0
no, cuz x^-2 = 1/x^2
wakamole
yes
wakamole
no, cuz anything times 0 = 0
wiatwut
this equation has no solution
which in turn means that 1/x has no maximums or minimums
wait so to solve the equation wouldnt it be $sqrt(-1) = x$?
wakamole
which isd imaginary
no, cuz in order to get to that step, you have to multiply 0 by x^2
ohhhh
which wouldn’t give x^2
wait but my book is saying theres an answer for a similar problem though
which one?
17
what did it give as the answer
ohhhh wait im stupid
it’s on a closed interval
so, we didn’t find any critical points, but we still have to check the endpoints
no yours is also closed
well 18 is open
i simply forgot
cuz it’s not just -inf to inf
but you are right about it not having a solution cuz it’s open
it looks like there is none still
ok ya
ha
if it was closed then it would have absolute i guess
even though i thought it would have local
i thought closed have local not absolute
absolute on the interval
but the answer to the last one has absolute
absolute on the interval as opposed to something like [-1, 2] ?
which would have a local?
no, the absolute max/min is just the highest/lowest point on an interval
if ur not given an interval, then you assume the interval is the domain of the function
it has to
im getting confused if abs max or local max includes endpoints
ohhh right
absolute includes endpoints local doesnt?
no, both can include endpoints
absolute or local is only decided by if it’s the largest one or not
it’s 1 not negative 1
and that’s cuz the endpoint ended up being the highest point on the interval
plugging in the endpoint into 1/x gives you 1/1 = 1
trust you got it
yeah thanks
you have a decent idea, you just need more help putting the pieces together
for the answers to this i can write no abs/loca; max/min.. right?
yeah
and my TA's arent helping me at all
really depends on ur prof
i always like to go extra just to make sure i get the point
i go to tuoring services 1ce a week plus TA hours
i just wana make sure i got the point to this
what unit are you guys doing
since we derived f(x) and tried to make it equal to 0 we found it is undef.
and since the interval is closed then it means there is no local or absolute min/max
i like to write the equation, then x = DNE, then “no max/min”
yep
i thought it goes on forever
ohhh
true
thx
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Very simple question but one I was wondering about. If a process is working at 150% efficiency and it takes 1s for the process to complete, 1/1.5=0.6666666666666667 (I usually write this as ≈0.66), what unit would you write that as? 666ms? 0.66s? 0.66th of a second? Or would you simply just put ≈0.66 without any unit?
This is entirely context dependent. If this is industry/academia try to be consistent with other reporting, and there’s probably a firm/institution/journal etc. style guide. Also you might want to look into sig figs
And if it’s for a class ask your instructor
Okay so, didn't know what sig figs were until now :o
What exactly am I suppose to do the significant figure of 0.6666666666666667 (16 significant figures)?
Like, I don't know what to do with the information :o
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Doing systems of linear equations and am so confused on how I should start this problem. I dont know how to set up the equations for this.
so, you might have something like this
lets work on club A
lets say that the fraction of students in A next year is like this
$A_{n+1} = F(A_n, B_n, C_n)$
jan Niku
ngl i havent seen that format before. Our teacher has only gone over like simple equations that we will turn into matrixes and solve
like the problem itself or the equations u just showed
ya if you turn it into equations, i just dont know how for this one
augmented?
they describe flow on a directed graph
maybe its markov
anyways
lets say $D = \mqty( A \ B \ C)$
jan Niku
let me show you what i did for a past problem so you can see how she wants us to do it
i didnt post the actual question but this is the general way she wants us to approach these problems
ya
so a 3x3 matrix
yes but i need three equations for that, which i dont know
so think of writing $MD_n = D_{n+1}$
jan Niku
were M is a 3x3 matrix
say M was the identity
what would happen
how would D change from n to n+1
bro ngl i dont even know what u mean by identity, neither have i ever seen that format u just showed
ok
half of the people in a go to b
half stay
and no one in b moves
im gonna use d = (a b)
a is proportion of ppl in a
blah blah
seem okay?
i see
so i can write this out
so this means half of a went to b
gotchu take ur time
$\mqty( 0.5 & 0 \ 0.5 & 1) \mqty(a_n \ b_n) = \mqty( a_{n+1} \ b_{n+1})$
jan Niku
this equation describes this flow
i want you to do the matrix multiplication
write a n+1 in terms of an and bn
so...i dont think we have done matrix multiplication, idk if that is later but our class started like a week ago
if u could show me that would be great
oh man its gonna be hard to type all this
wait wait
before you do
do you think u could try and do the problem like this
or really just step 1
because thats all i need
its like this
An+1 = 0.4An + 0.2Bn + 0.2Cn
n+1 and n mean step
this is just the first eqn
do you see how i got those numbers?
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Hello
I'm confused about what this whole page of notes is explaining, but especially part of Descartes rule of signs. When it says "then it differs by a multiple of two". Like why is it by a multiple of two? I can try to get a better picture of my notes if that would be helpful
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how odds work?
Take this as an example:
I bet 10 bucks on something. My friend does the same. If I win, I get mine 10 bucks + his 10 bucks.
Total win: 20 bucks.
If I say I want to bet 10 bucks with 3:1 odds what does it mean?
I understand that if I win, I will get 3x the value I originally bet, is that correct? If so, how much did my friend bet? It wouldnt be fair if we agreed on 10 bucks but when I win he has to pay me 3x more.
I dont understand how this works
@unreal peak Has your question been resolved?
I understand that the winner will take home 3x his original bet value, right?
But if only two people are playing this, from where will come the extra money?
Look: If 2 people are betting 10 bucks each. The prize pool will be 20, and the winner will get 2:1 thats understandable. But where will the extra money come from if they agree on 10 bucks initially but with 3:1 odds?
You may say the other party will pay the extra 10 bucks, but by doing so, wouldnt it be the same as agreeing on betting more money initially?
Also, wouldnt it be silly to bet on a promise of payment where you dont see all the value but rely on the other party to pay you later a bigger amount?
ok so 3:1 odds
however, for the other person, it's 1:3 odds
if it helps, think of it like this
the total is 4, which is the combined value of the odds (3+1)
converted into percentage, each number is worth 100/4 = 25
so 3:1 odds means 75:25 - you have a 75% chance of winning
for the other person, they have a 25:75 or 25% chance of winning
if you both bet $10, the winner (regardless of who it is) will walk away with $20, and the loser will walk away with $0
Now, if someone says they'll give 3:1 odds, that means the person with the 3:1 odd is willing to pay 3 times more because the chance is 3 times less likely
it is not like the $10 and $10 example - the people agree on $30 to $10 at the beginning
does this make sense?
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Hi I need help with a matrix transformation question
Ill share the set up of the question, its from a university resource I found online
I know that if a matrix A is the standard matrix of T, its size has to be 3 x 2 (am I right)?
Height 3, width 2, yes
But how how would I find what matrix A is?
You have an easy shortcut in this case:
I suggest first getting T(1,0)
See how it's done in this case?
That's okay. Note they give
T(1,-1) and T(0,1)
If we add them:
T(1,-1) + T(0,1)
= T([1,-1] + [0,1])
= T(1,0)
Ah I see
If you have the transformations on the standard basis, then the matrix is just given by the outputs stacked into a matrix
Okay so that works luckily in this case then, but if it were something like T(-1, 4) and T(1, -1) that they have given us, how would we proceed then?
Would we do scalar multiple multiplications or similar?
if you want to repeat this approach, you could always find what linear combinations of (-1,4) and (1,-1) you'd need to take to get each of the standard basis vectors
right, so in the case I just created how exactly would that work - would we still be working to find T(0, 1) and T(1, 0)?
wait sorry I did not understand this
to get the matrix representing the transformation
see what it does to the standard basis vectors
and write the transformed versions of those as the columns
you don't know what T does to (1,0) or (0,1), but if you can take some linear combination of T(-1,4) and T(1,-1), maybe you can find T(1,0)
you're allowed to take linear combinations of these since they're linear transformations
So if we want to T(1, 0), we could do T(-1, 4) + 4T(1, -1), which gives T(3, 0), and then divide by 3
Is that the right idea?
But how would I write something like that out, because going back to the original question, the solution did something like this
Would the divide by 3 be outside the whole thing?
yes
technically the dividing by 3 is the same thing as 1/3 T(-1,4) + 4/3 T(1, -1)
which is the same as T(-1/3, 4/3) + T(4/3, -4/3)
which is the same as T(1, 0)
Would you mind terribly if I asked if you could write it out in a similar format and share a picture - I'm slightly confused on how to write it out, once I have T(1, 0) I can do T(0, 1)
write what out?
do you agree the matrix representing T here has T(1,0) and T(0,1) as its columns?
The thing that you are explaining, but in a similar format to how the picture shows it
Yup
so we want to find what those are
let me try to latex it
That works, I appreciate it
you used T(-1,4) and T(1,-1) as examples but never said what they actually were
let's say you knew T(-1,4) = a and T(1,-1) = b for some vectors a and b
then you know that T(1,0) = 1/3 T(-1/4) + 4/3 T(1,-1) as per this reasoning here
this is better, because I made up the -1 and 4 part to explore different version
then you know that T(1,0) = 1/3 a + 4/3 b
of course if you had the vectors a and b, you could write this as a single vector
which would form the first column of your matrix representing T
I see, let me try it out for T(0, 1) too
Okay I think I solved it
There was a question after this that asked to find a vector in R^2 whose image under T is a vector they gave
And I used the A constructed from (T[1, 0] T[0, 1]), and augmented it with the 3rd vector they gave. I then turned into RREF, got x1 and x2 as basic and x3 as free, and x1 and x2 ultimately turned out to be 1 and 0 respectively, so the vector in R^2 was x = [1 0]
Thanks for all your help
If i have more questions ill come back
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would this be 7 over tan 55 degrees?
Yep
@vernal acorn Has your question been resolved?
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if a matrix has Nul(A) = 0 then is it guaranteed the linear transformation x to Ax is 1:1?
i think yes because it means all col are pivot columns which is a req for 1:1
@random grotto Has your question been resolved?
<@&286206848099549185>
Yes. The kernel is trivial iff the transformation (or its associated matrix) is injective,
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Are -1/3 , 1/-3, and -(1/3) the same slope??
Like in the end my line will be the same right
they are all the same number so yes
a way u can check is to test them with real coordinates to see if they are the same slope
and do rise over run to find if they are the same 🙂
Ohh ok
-1/3 = 1/-3 = -(1/3)
yup!
-3/1 = 3/-1
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How would you tell this is a perfect square?
(a+b)^2 = a^2+b^2+2ab
the middle should be 2ab tho, so 2(2)(9) instead
yeah this one
its just a coincidence that 36 is also a perfect square
yea
like (x+2)^2
np
I’m still kind of confused, what steps would you take to figuring out the perfect square
see you factorise it
check if the first and last terms are perfect square
you can identify if it's in form of a^2 + 2ab + b^2 or a^2 -2ab +b^2
then you can be sure that it's a perfect square
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if I want to understand easily about polynomial equations better, what kind of math topic should I review?
polynomials
its really confusing to factoring those numbers and had to group them
You should learn some basic algebra topics
Such as polynomials (monomial, binomials trinomials), linear equations in 1 variable 2 variable 3 variables, system of linear equations,
quadratic equations
And in addition you can learn to draw graphs of linear equations
@bronze shoal Has your question been resolved?
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can someone please explain when exactly I use the => arrows in math? I know that it means "X implies Y" and I know that <=> means "X implies Y AND Y implies X" but I don't know when not to use them
like for example when I have to use the quadratic formula for an equation, does it matter if I use the arrows there?
x = 238
y = x +2
=> y = 240
that I understand
its not necessary to use implies for a quadratic equation
I'm not sure when for example I got something like this
its not an incorrect usage of it, but its not necessary
when is it necessary? because my exam deducts points for not using them when needed
or if you don't use them you have to write down a check for if your answer is correct where you plug in x that you found
so far I know that I have to use them when applying algebra and that I have to copy the whole equation everytime I do it
so for example
x + 2 = 0
=> x = -2
and not
x + 2 = 0
=> -2
but that's about it when it comes to my understanding of it
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Hello
I need help with one radical

!da2a
No need to ask “Can I ask…?” or “Does anyone know about…?”—it’s faster for everyone if you just ask your question! See https://dontasktoask.com/
where you learn these commands/?
just by being active 
#helpers-info has a list of commands
@solemn compass Has your question been resolved?
Thats the exact same question like yesterday lol
tf
@solemn compass Has your question been resolved?
v has to close it or you have to wait for it to timeout
'@solemn compass '
ok
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Someone help me with b?
find it's circumcenter
How exactly?
by drawing perpendicular bisectors
and where they meet is known as the circumcenter
So i should draw a perpendicular bisector on all A, B and C?
no any two sides would be enough
I see
Once I find the circumcenter do I just draw a circle that touches lines A, B and C or just make it big that it passes through them?
no it should just pass through ABC
Steps:
Construct the perpendicular bisector of one side of triangle
Construct the perpendicular bisector of another side
Where they cross is the center of the Circumscribed circle
Place compass on the center point, adjust its length to reach any corner of the triangle, and draw your Circumscribed circle!
Would this be correct?...
show
Ohhh
Ahhh
I get it now
Wow thank you so much for your time and teaching
Didn't know it was that easy
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can i please have some help?
can someone please tell me how to complete the square?
,tex .cts
ℝαμΩℕωⅤ
i dont have a question im asking how to complete the square because idk how
let's use the image above
i dont really get the image
what do you not understand
where the c came from
ok we'll ignore that for now
let's take this example
x^2 + 14x = -24
first step of completing the square
we always divide the 'b' term by 2
in this case we divide 14 by 2
so that gives us 7
now we square it
so we get 49
now whatever we do on the left side
we do it on the right side
so we add 49 to -24
so it'll look liike this x^2 + 14x + 49 = -24 + 49
now can you tell me what the LHS simplifies to?
idk is it x^2 + x +49 = 25/14?
nope
basically i want to know the factored version of the perfect square trinomial
so x^2 + 14x + 49 is what we call a perfect square
and it's a trinomial because it has 3 terms
the x^2
the 14x
and the 49
do you know how to factorise?
kinda ive done it before so i kinda remember but im not 100% sure
yep
that's why it's a perfect square
i can't explain what a perfect square is perfectly
so I would search it up
so when we complete the square we're just trying to make the LHS a perfect square
ohh ok
x = -2
yes or x = -12
plus minus
surely its (x+7) = 5??
square root gives pluse/mines 5 for 25
yes
because if u think abt
it
waht does -12 + 7 give u
i['ll just answer it it gives u -5
and -5 squared is 25
now do the same for -2
-2 + 7 = 5, 5 squared is 25
therefore x can accept both values of -2 and -12
hence we get plus minus 5
im confused where -5 came from and where -12 and -2 came from still
ok so let's go from (x+7)^2 = 25
if we square root the value
we're left with x+7 = plus or minus 5
reason being is because either plus or minus 5 works if we square it
cause it's going to give us 25 either way right?
so surely its either x= -2 or x=12?
hows it -12?
-5 - 7
not js 12
essentially plus minus 5 is like having two cases
but surely plus or minus so 5 + 7 = 12 and 5-7 = -2
ok
and minus 5 (negative 5 basically) is another case
if we take case 1
we completely ignore the minus
we assume 5 is just positive
so when we move the 7 to the other side
we get 5- 7 = -2
now scrap the first case and focus on the second case
assume 5 is negative and not positive
so x+7 = -5
x = -5 -7 = -12
do you understand?
ohh ok yeah i get it thanks so much for ur help
you're welcome
ive got a exam in a few days and i didnt rly understand how to do that
will do
if you have a notebook or like a spare piece of paper, write this down
yeah im also taking screenshots
thanks
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not sure how to start?
what is h_3?
huh
h1=100
ye
r=0.9
100 * 0.9 * 0.9
100 * 0.9 * 0.9 * 0.9
Flappie
$h_1=100\h_2=1000.9\h_3=1000.9*0.9$
ye
Flappie
yh
do u not notice anything
how would you write this in terms of n
so that we can find the height of any arbitrary bounce
close
0.9 times of n
how would you write 0.9 times itself, n times?
0.9^n
100*0.9^n
ye
we want the height of the ball
to be less than 25 cm
after how many bounces does it achieve that
100*0.9^n<25 ?
take the logarithm
so log10 0.9^n < log10 0.25 right?
yes
no
you have to round it up
100*0.9^13=25.4
which is just above
so you have to let it bounce one more time
i twill become n<13
which is the same
13
you have to round it up
not down
the threshold is inbetween two whole numbers
if you take the lower number
then it wont have passed that threshold yet
and =thus is not the number we are looking for
so you have to round it up
👍
@meager glade For b how do i actually start?
you need to take the sum
you need the total distance it has travelled
and that is each height
summed
Its height is 100cm
How do i find the distance travelled
what is the distance it travels between each bounce?
its goes down
and up
what is that distance
Theres no distance in the question
whats the height?
0.9h
is that not a distance?
Oh
I thought u meant the distance between em like left and right thats why i got comfused
100-(100*0.9)
Yh
yep
i dont see how else
you want the total distance
so you have to add up all the up and down bounces
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for a group with infinite order, such as 2^n
n=0 is technically the order
so why isn't the order 0, but rather inf?
thats what im asking
he did r-s saying that the only way it can equal the identity is by it's exponent being 0
but, how is that a given
abstract math seems to put exponents into recipe without telling and it's stupid
i
i'm okay with it being exponantial but
that's literally the definition of an element having infinite order, if a^n = e implies n = 0
if it has an order, a^0 = e, then it means that ord(a) is zero, not infinite
oooh
so inf order = 0 order?
if you want to think about it like that sure
that's stupid, thanks for help
abstract algebra makes less sense the more i learn it
think about it like this
a generates some subgroup
the order of a is the number of elements of this subgoup
if the order is 0, this would imply that the subgoup is the empty set
can't be tho
2^n isn't empty tho
because it contains at least a
right
that's why it makes sense for the order to be infinite
run a function zero times, and you get the identity
i believe this means this
but if you run a function zero times, also, not run it
you don't get anything
not even the identity
there is no esoteric reason why a^0 = e, it's defined to be like that so that the exponent rules make sense and {a^n in G | n in Z} is a subgroup.
it's just a notational device
no
if o is the operation a^n = a o a o a ... o a n-times
it's just a matter of definition
and if you have say $a^n$ and $a^{n-1}$ then $a^n * a^{-n} = e$ obviously
belabutter
multiplication*
i believe, is the thing i should have said
so for the exponent rules to make sense we define $a^0 = e$ so that $a^n * a^{-n} = a^{n-n} = a^0 = e$
belabutter
np
by the definition of order, a^r can't equal e, so why must it be r=0?
im certain that in the definition of order,
it was
0 =< x < n, x != e
i acknowledge that we need to set r to zero, to make a^r equal to e
but doesn't that contradict the definition of order?
that's the rule i believe
does it allow a^0 being e?
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why is 24 being divided by 4000?
Flappie
so if oyu take the inverse $\int\cos(4000t)dt=\frac{1}{4000}\sin(4000t)+C$
Flappie
is it the "t" which makes you require the chain rule in this case?
im looking at pauls online notes and it seems different
cos(x)dx = sin(x) + c
not xsin(x) + c
4000t = x
right?
err
I haven't actually reached the chain rule for integrals yet in my book so im not sure
only for derivatives
yes, but $\int \cos(ax)dx=\frac{\sin(ax)}{a}+C$
sin(ax)
Flappie
,w int cos(ax)
and since hte constant in the examples is 1 (a=1), you divide by 1, and thus doesnt do anything
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im using the product rule
!show
Show your work, and if possible, explain where you are stuck.
give me a sec
you can use implicit differentiation as follows:
first divide both sides by the radical, then square both sides, then take the derivative and solve for y'
almost
you need to multiply the first term with the derivative of whats inside the sqrt
$\frac{d}{dx}\sqrt{f(x)}=\frac{f'(x)}{2\sqrt{f(x)}}$
Flappie
can any1 here help me with limits
open a empty chat
help-13
oh, I was playing with the expresion and I got to the answer
how can I close a chat_
?
@ruby wyvern Has your question been resolved?
type .close
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is an algorithm that runs with expected runtim O(d * n) still considered an efficient las vegas algorithm if d in N+.
The thing here is that 1/d is the difference of two terms in my analysis and here 1/d is between 0 and 1. Then d can be any positive integer. Which makes this whole runtime weird because it could be arbitrarily large.
Does anyone know how to judge this ?
Can n also not be arbitrarily large?
I am maybe not understanding what the issue is. What information are you trying to extract out of the big-O runtime?
@wicked crown Has your question been resolved?
well n is the input
I want an efficient probabilistic algorithm for a good independent set
now I have some bound on the independence number
I'm not certain but
and I am trying to derive a las vegas algorithm
Now usually if the graph has m edges, then the las vegas algorithm needs to run O(m) times to find a good set. But unfortunately my analysis tells me that in some cases there might be a value d that can be arbitrarily large, depending on what the fractions do in my term, but it does not directly depend on the graph size
yes but
as far as I know big O notation doesn't refer to how fast or efficient an algorithm is but how well it scales as n does
if we have something like 10^10 * O(n) thats not pracitcal
thats the thing
technically its linear in the edges
but by analysis it could have some insanely large constant
well
and I didnt find any way to bound that value
O(n) is still the worst case scenario
what language
oh it's not a program?
lol no its math
😭😭😭
didnt implement it yet
I'm not quite sure how it would work in math
wdym
next person may find it useful
I kind of asked this in here a few times already lol
nobody seemed to want to take a look
I know that the expected size of an independent set is n^2/4m
therefore there is an independent set with size at least n^2/4m
without looking at it too much wouldn't that be O(n*m)?
What in the computer science is this
this is in O(m) expected ?
1/3m+1
is the probability that a randomly constructed independent set has size at least n^2/4m
so geometric distribution has expected value 1/p
here it is >= 3m+1
O(m)
in the case where the ceil(n^2/4m) is in N
the other case is the tricky one
the difference in the numerator can be arbitrarily close to 1
therefore 1-D = d can be arbitrarily small
so the fraction can skyrocket as far as I am concerned
forgot this
where U is an indpeendent set in a graph G, randomly selected by a certain method
and n is at most 2m
the only relation we know is that 2m >= n
other than that you could have everything up to m = n choose 2
so that would be O(n^2/m) then, no?
why ?
cause we have two things that change
but by bounding n through m , I get rid of n ?
also we know that m is always in O(n^2)
its at most n choose 2
u said that n=2m
worst case scenario