#help-49
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O
Do you have a math question to ask?
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This is my problem
But I only want to know the second question
what are the nul-točke
solution is:
But why we only take the numerator's nul-točke?
And not the denominators?
because denominator's nul-točke is 1, -1
nul-točka: points where the parabole cuts the X axis
first of all
the denominator's null points
are the points where f is not defined
since
if denominator is zero
then f(x) would be .../0
Ohhhh
division by 0 not allowed, doesn't exist
Yes, I see now
a/b = 0 is the same as
a = 0 * b
which is a = 0
so
the denominator's null points are points outside the domain
the numerator's null points are the null points of the function
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Snitch.
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is this correct ?
@chrome ibex Has your question been resolved?
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Hello, is this correct:
Injection: when no y element of Y doesn't have more than 1 x element X joined?
Also, is this correct:
Surjection: when every y element of Y has at least 1 x element of X joined?
this one is correct
Injection: when no y element of Y has more than 1 x element X joined?
when none y has more than 1 x
correct?
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Markov Chains question, I'm not entirely sure how to start
Maybe law of total probability at the start to introduce invariant dist
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@tepid breach Has your question been resolved?
nvm I cooked
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hihi
problem:
y = -x^2 + 5x + 6
and we're also given this formula:
-b +- sqrt(b^2 - 4 * c)
/
2 * a
and you gotta like seperate them
it's a perabula thing
now, the answers page says that the correct answers are: (6,0),(-1,0)
but I can't get it.
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are you sure that formula is write
yep
a is just 1
because the coefficient(number infront) of x^2 is 1
but obviously we dont write the 1
but isn't it -1?
what makes you think that
ohh ya its -1 then
it's this:
y = -x^2 + 5x + 6
okay your formula is wrong then
you missed out the a in the discriminant (square root)
it's +- because you divide it into two parts:
one for an exercise where you do subtraction
and one for an exercise where you do addition
and then you get two x's
do you understand why you need to do the plus and minus?
well why
so you'll get the two points where the perabula touches the y axis
you mean x axis?
yeah I mean x mb
okay well
the formula above is a general solution to equations in the form Ax^2 + Bx + C = 0
so in this case
-x^2 + 5x + 6 = 0 (because y=-x^2 + 5x + 6, and at the x axis the y value is 0, so you can replace the y with 0)
aight hang on
i think you should understand why we take the plus and minus of the square root
what?
I honestly have no idea why we do that
consider the equation x^2 = 1
first time working with perabulas
solve that for x
ok. what's (-1)^2
1
hence, -1 is also a solution to x^2 = 1
so wheneveryou need to take the square root to solve for a variable, remember you must include the +- to account for the negative root
i just felt that was quite an important piece of intuition for this topic
alright so back to the quadratic
-x^2 + 5x + 6 = 0
we have it in the form ax^2 + bx + c = 0, so we can apply the quadratic formula to find our values for x that satisfy this equation
as we said,
a=-1
b=5
c=6
what's ac
its a multiplied by c
so instead of 46, you would have 4(-1)*6
ok
the 4 is italisizing
its a?
read this formula
100%
it wasn't there in class, it only showed up as the 2*a
perhaps you were only dealing with quadratics where a=1
but tbh i have no idea why it wouldnt be there
oh it is thereee
okay I see it
the square root says:
sqrt(b^2 -4 * a * c)
is this right?
yes
1 for what?
i did:
sqrt(5^2 -4 * 1 * 4)
for the square root
as in: this has the wrong value for c
so you have computed the square root but not the whole formula
remember
so rn you're at -b +-(7) / 2a
I got
(6,0)
(-1,0)
that is correct
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The answer is y = a(5x+2), with a < 0
I'm trying to understand this but I simply can't
What is an affine function?
f(x) = ax+b
Ah just a linear function 
Yes
Consider the point slope equation for a line. Do you know it?
||(No difference in english? Cuz affine is ax + b and linear is ax to me)||
Yesss
At least in my language it's like that
Also its in fr and we have wierd enough stuff like that
Portuguese as well...
I'll close this chat and try to search for my teacher to get a reply... because WHAT A QUESTION 
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It could simply be y = -(x+2/5)
(x + 2/5)y < 0
Is the written condition basically, or you could manipulate it to be
y/(5x + 2) < 0
So just put it some constant C, with C < 0 and you're good to ho
Not ho, *go
@sudden yacht Has your question been resolved?
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How do I make most of the terms here cancel out?
I think we could use the fact 1/(n*n+1)=1/n-1/(n+1) here
at first glance, it looks like you would want to consider telescoping series (but I could be wrong)
that looks useful
$\frac{1}{(2n+1)(2n+3)}$
it cant hold even stuff
2n+1 and 2n+3
knief
n from 0 to 99
oh ok
@mint ravine do you know partial fraction decomposition
no
its coming
Am I supposed to?
$\frac{1}{(2n+1)(2n+3)} = \frac{A}{2n+1} + \frac{B}{2n+3}$
yes
knief
what i did was multiply and divide by 2
solve for A and B
A=(1-B(2n+1))/(2n+3)
yeah that's what was i did
then set n = -1/2 to solve for A
and set n = -3/2 to solve for B
$1= A(2n+3) + B(2n+1)$
knief
yeah i got that expression after multiplying both sides by the denominator on the left
did you do this
do that
because it will make the other term be zero
so you can solve for A and B
B=1/-2
$\frac{1}{2(2n+1)} - \frac{1}{2(2n+3)}$
knief
knief
knief
so you can write out a few terms to see what’s going to cancel
and pull out the 1/2 tbh
Sorry this is much better
thanks naruto
so it's 1/3 - 1/201
If you look at the formula the top of the summation is n-1
so in this case n-1=99
n=100
That multiplied by 1/2
Oh and we have an issue
The summation on the formula starts at 1
But in the problem it starts at 0
Guess what to do now?
You have to add the first term to the formula
so replace by 0 and add it to what we have
so 1 - 1/3, all multiplied by 1/2
so 1/3
so if i did my math correctly
the answer should be 601/903
Let me check
and you can't simplify it anymore since 601 is a prime
This was equivalent to 0.49751243781
This is 0.66555924695
you have to add 1/3 to it
nevermind
i see my mistake
thanks for helping everyone
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am i actually tripping or aren't there infinity many solutions to this
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5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
shit i didnt realise that was from long ago
Lmao 
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hello ! I have a problem with partial derivative in a 3 D space !
i must find the partial derivative in
that's the proposition i have
but 0.7 is not the correct answer 😅
so my idea of how to fint the partial derivative might be wrong
i also have this graph in y=1
thanks y'all in advance !
so i suppose that's it's negative
but why looking at the graph with z ?
OH OKAY
THX
i just understood
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Should be 5ms
working out?
No m done. Just wondering the context of "first time waveform reaches 220V"
Well anyways, the first time waveform reaches 220V is in T/4 time and T = 1/f
So 1/4f time or 0.005s = 5ms
@leaden seal
Naah that's just rigorous
okay
π/2 is reached at T/4 time anyways. And if frequency is already given, it's better for mcqs to not overcomplicate
Plug T = 1/f, compute, onto the next ✓
right
Btw I'm curious why your Vpeak = √2 • 220V
its a formula
But Vpeak = Vrms √2.. it isn't mentioned in q that Vrms is given
Anyways, hope you got this
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hii, I still don´t understand the difference between asymmetry and antisymmetry. The following set {a,b,c,d} and relation R = {(a, a),(a, c),(b, b),(b, d),(c, c),(d, d)} were given. Why is the relation R not asymmetric but antisymmetric :((
well, what's the definition of asymmetric, and what's the definition of antisymmetric?
the definition of asymmetry is: if x R y => y is not in relation with x
and antisymmetry means x R y and y R x => x = y
well it is antisymmetric because it isn´t symmetric
...what?
but I don´t know why it is asymmetric
ok wait what's the definition of symmetric
okk,soo it means that if x is in relation with y, then y needs to be in relation with x too for example
well that's not the negation of antisymmetric
that is symetric yes
the relation R = {(a,b),(b,a),(c,d)} isn't symmetric, because cRd is true but dRc is false, and also isn't antisymmetric, because aRb and bRa but a isn't equal to b
but to prove antisymetric the most used method is if you have xRy suppose yRx and try to prove that in this case that always x will be equal to y
most used method
...well yes because that's the definition
okkk, does that mean that if we have something like
and no that's not the definition of asymmetric
it's the definition of symmetric
? xD
bro sry to ssay this but u gotta take back that claim if u not sure try to not share missinformation please
R = {(a,a),(b,b),(c,c)} this is symmetric, reflexiv, transitive and antisymmetric, right?
yes, assuming it's on the set {a,b,c}
you're the one who's spreading misinformation actually
why what was wrong?
can you read my emssage again and tell me what is wrong "undergrad?"
the message you were replying to here is the definition of symmetric
you said it's the definition of asymmetric
or, well, "assymetric", which would be a pretty strange way to misspell "symmetric"
anyways i'll break it down to you easily . to prove symetric you need to have is when xRy you need to prove that yRx aswell . for antisymetric you need to prove that for xRy then y sin't in Relation wtih x ( as i said the best method for this is to suppose xRy and yRx and prove that x=y always in this case ) ; for transative u need to prove that when you ahve xRy and yRz prove that xRz
for antisymetric you need to prove that for xRy then y sin't in Relation wtih x ( as i said the best method for this is to suppose xRy and yRx and prove that x=y always in this case )
false
that's the definition of asymmetric
it is true that all asymmetric relations are antisymmetric, but not all antisymmetric relations are asymmetric
xRy and yRx => x = y is antisymmetric
yes
try to focus in this
why are all asymmetric relations antisymmetric?
well suppose R is asymmetric, and consider two elements x,y such that xRy and yRx
assymetric means if xRy then Y can never bever in relation iwth x
this situation is a contradiction because R is asymmetric, therefore by the principle of explosion x = y
which proves that it's antisymmetric, because we showed that if xRy and yRx then x = y
waitt
if it is asymmetric, that means that xRy but yRx is not in the relation,right?
exactly
and it is antisymmetric because xRy and y is not in the relation => x is not equal to y ???
R is antisymmetric if whenever xRy and yRx, [something else]
but because R is asymmetric, "xRy and yRx" just never happens, so it's true vacuously that R is antisymmetric
ohh,just because it never happens?
no, it's antisymmetric because if xRy and yRx, then x = y
but yeah basically it's just, "xRy and yRx" is impossible, so it's saying "every time [this thing that never happens] happens, x = y"
and that looks like (a,a),(b,b) for example?
or a different way to look at it: there can't be a counterexample, which would be two x,y such that xRy and yRx, and yet x != y, because the "xRy and yRx" part is already impossible
well no, the relation {(a,a),(b,b)} is antisymmetric but not asymmetric
because if you take x = a and y = a, then xRy and also yRx
because aRa and aRa are both true
i'll give you an exemple take the relation < . if xRy then x < y and y can never be < x
wait, i need to reread your explanation
so taht means if x R y then y can never be R x
@shut goblet i believe this exemple should be very easy
ohhh,rightttt now I got it I guess
np :)))
and to be clear, while "symmetric" does sort of feel like the "opposite" of "antisymmetric"/"asymmetric", they're not actually negations of each other
the relation {} is both symmetric and asymmetric
again for vacuous reasons, "symmetric" and "asymmetric" both start with "if xRy, [...]" and that never happens with the empty relation
THANKS A LOT, I really thought that it was just the opposite of symmetry
well depends on the prespective
there are also a lot of relations that are, intuitively, "sometimes symmetric and sometimes asymmetric", and end up not being symmetric or asymmetric, which both assert that it always happens a particular way
ohh, do you know how I can practice this topic?🥹
{(a,b),(b,a),(c,d)} isn't symmetric, because the (c,d) part makes it not symmetric, and isn't antisymmetric, because the (a,b) (b,a) part makes it not antisymmetric
yep
and if you had {(a,a),(c,d)}, then that is antisymmetric, but isn't symmetric (the (c,d) still breaks it) and isn't asymmetric (because of the (a,a))
omg, thanks
there was the following relation given:
R = {(a,a),(a,c),(a,d),(b,b),(c,a),(d,a)}
Why is R transitive?
I thought that it is not possible to be transitive bc {(c,c),(c,d),(d,c),(d,d)} are missing
...oh, huh, good point, i missed that lol
yeah you're right, this isn't transitive
cRa and aRc should imply cRc, if R was transitive
yeah i think your teacher just didn't notice that
which tbf i didn't either until you pointed it out
does my solution makes sense?
i think i would have given more detail to make it more directly related to the definition of transitivity, instead of just listing the pairs that were missing and leaving it to the reader to work out what exactly is wrong with them
like i did here
but you definitely had the right basic idea, because those are the pairs that should be there but aren't
like cRa and aRc => cRc ∉ R?
for example
or like it should imply cRc, if R was transitive
...i mean that's kind of a pile of symbols that doesn't exactly make grammatical sense, specifically "cRc ∉ R" is a bit odd, but yeah basically
"cRa and aRc are both true, so if R was transitive, cRc would also be true, but it's not, therefore R is not transitive"
yeah, you are right it is a bit of odd I should write it like you did it
makes things for everyone clear
i am really,really thankful for your patience and explanations
thanks a lotttt!!
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how did this get simplified
$\sqrt[n]{x} = x^{\frac{1}{n}$
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And
So
@grim monolith Has your question been resolved?
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Can anyone proof to me why does odd root can have a negative number inside of it?
what number multiplied by itself 3 times is equal to -8?
-2?
Yes, now can you find a number that multiplied by itself is -4?
I mean, if you think about it, (-1)^3 =-1 so (-1)^(1/3) would be -1
same thing with other odd roots
This happens because negative times negative times negative is still negative, while there is no sign that multiplied by itself is negative
On real numbers
This is the signs rule
I think there are no number to it
So for square roots you have only two options: negative x negative or positive x positive
Both of them will give you positive
But what happens with cubic roots? You have negative x negative x negative or positive x positive x positive
are u asking for intuition or proof
In the first case, from the picture above, negative x negative is positive, and that times negative will give you negative
In the second case, positive x positive is positive, and that times positive will give you positive
So for the cubic root you may find the root for both negative and positive numbers
But for square roots you may only find the value for poditive numbers
OOOOO
I seeee
Basically the square of any number is positive so the value inside of the square root must always be positive, while on the other hand, odd root can have negative number like (-2)³ is -8 or 2³ is 8. therefore it is acceptable to have negative number inside of the square root
Is this correct?
yeah
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I'm unable to understand the 7th question, that when we take coefficient of highest power as unity, theres only a single answer?
Fundamental Theorem of Algebra
juaincha do you know wtf "highest power of the unknown be taken equal to unity" means
Yes
How does it apply here?
Maybe it helps to reduce the amount of solutions
But we need complex coefficients for that?
If the highest power of the unknown is 4, then the amount of solutions are 4. Now if it is not 4, the solutions decrease
I don't think
It says coefficient of the highest power, so if it was 4x⁴ now it's x⁴
um
It's bc you can just simplify things
is it asking why is there only one polynomial that satisfies ex 1 - 4
the grammatical errors are throwing me off in the question sorry
She said it's bc why do we use (x-r1)(x-r2)=0 instead of 3(x-r1)(x-r2)=0 let's say
But it's bc they're equivalent
Ohh
Moreover, they ask for "a" equation
okay I think got it
its the same thing as writing 100 x 0 or 1214124 x 0
they both become 0 anyways
doesn't matter what number I put before it
I understand, thank you!
Np
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Does anyone know of any physical calculators that are affordable and can be used for the SAT?
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What is Simon's Favorite Factoring Trick and how does it correlate with the Diophantine Equation?
Show where you're reading about Simon's favorite factoring trick
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You don't have to be unpleasant, people here are just volunteers
And you're not supposed to get help on these problems
So this was a lie
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is it sufficient here to say that when T = 0 (the zero map), p(T) = 0 so the set becomes just {0} which is not L(V)
im not sure if it means these are not equal for ANY T or there is some T where they arent equal
im leaning towards the former
what does $\mathcal{L}(V)$ mean again?
Arnavutköy
ok i will leave this for somebody else to help you with then
p(0) is not necessarily 0, though
oh wait ur right what am i talking abt
would it be p(T) = aI for some scalar a
I is identity
But that should still qualify as a counterexample
yea it would
my main issue is just with this wording
They mean it can't be equal for any T
So your argument doesn't prove it for all T
yea
i think i can figure it out for all T, i just was unsure abt the wording
ty!
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oop
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✅
the dimension of the set here is equal to dim V but dim L(V) = (dim V)^2. since (dim V)^2 < dim V (we are given dim V > 1, which guarantees this), we cannot have equality
i think..?
why is the dimension equal to dim V?
or i guess its less than or equal to dim V
wait
hold on my brain isnt working rn
this exercise appears before chapter 5B so presumably you should not know that fact yet
yeah i knew it because im just reviewing stuff but i was trying to think of a way to prove it without relying on stuff thats not in the book yet
why doesn't it work for dim V = 1
then dim L(V) = 1 so every nonzero T is a basis of L(V) and we can construct any other linear operator U as a multiple of T
there is a simpler explanation
yes
hmm
yeah
which also happens to be a number right
well lets say ive got some polynomials p(x) and q(x)
im not sure what youre getting at
mhm
ok
mhm
oh we have commutativity?
mhm
uh im not sure what's useful to say about it
hint: you've already said it
everything in it is just numbers
perhaps the example with V = F was confusing
lets take V to be any vector space now
not necessarily F
so T is a linear map V -> V
mhm
and p(T) is some expression like T^2 + 5T - 2I
yeah
what can you say about p(T) q(T)
remember this
mhm
p(T) q(T) = q(T) p(T) still right?
yes
they dont typically commute
no
do you see the argument now?
yes i do
and when V = F, as mentioned earlier, everything is just numbers
so you just have commutativity always
thats why it fails
and dimV > 1 because when dimV = 1 the operators do commute?
ye
nice
ill try and use this to make a complete proof, tytyty <3

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i suppose an unbased solution would be to look at the invariant subspaces 
so my proof was to let U,W be arbitrary operators on V that do not commute (which is always possible with the guarantee that dim V > 1). then for sake of contradiction assume {p(T): p in P(F)} = L(V), which lets us pick polynomials p, q with p(T) = U and q(T) = W. then p(T)q(T) = q(T)p(T) but UW != WU, a contradiction
alternative solution btw
this is probably the indended route lol
i like this proof though :>
the eigenvectors of T are eigenvectors of p(T)
so you just find S with different eigenvectors
hm no this might mess up when you get weirdness like p(T) = I
then everything is an eigenvector
commutativity is definitely more based
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i need to prove AY is the diameter of (ABC)
if we take quadrilateral BHCY its a paralellogram right
since the diagonals bisect eachother
i just wanted to know for any quadrilateral if the diagonals bisect eachother we can say its a parallelogram
i took angles and proved ABXC is cyclic
ok
i wanted to know if this is sufficient to say HBYC is a paralellogram
HYBC is a parralelogram and H is the orthocenter is sufficient
yeah yeah i just wanted to know if saying the diagonals bisect eachother is enough to prove HBYC is a parallelogram
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hi, for a triangle with fixed perimeter, the area is maximized when it’s an equilateral triangle right?
Also what about if two sides are fixed? then maximum area is when it’s a right triangle?
yes
okay sure, nice
what about this?
you mean when the perimeter is not fixed but we know 2 of the side lengths? yes then the right triangle where the two sides are the legs
i guess yeah
why?
also this person is wrong then right?
well one way to think about it is the area of a triangle is $\frac{ab\sin(C)}{2}$
Arnavutköy
if two of the sides are fixed and the perimiter is not fixed then yes it is when its a right angled triangle
hmm fair
so the person that responded is wrong right?
also no trig allowed 😭
yeah
any geometric proof?
base times height over 2
uhm like i guess for a fixed perimeter a square has the greatest area so we want it to be as close to a square?
so take one of the edges
and make that the base
the height will always be less than or equal to the second side
the case of equality only happens when the second side IS the height
which implies that both sides form a right angle since they are the base and height
for fixed perimeter, the maximum area of an n-gon is the regular n-gon
why?
but okay i see the intuition nonetheless
if u have two sides and if u fix one as the base
the area is maximized when you make the height orthogonal to it
given 2 sides why can’t u like try to make it regular?
why right triangle and not “as regular” as possible
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Convert this to parabolic equation
||4(y^2-5y+6.25)-6.25=-12x-67||
should be -25 outside the brackets
why 25/4
-25?
ok in our syllabus they reduced perfect square for 10th lol
so i don't know what method you're using
completing the square
ye but why (2.5)^2?
https://youtu.be/prx_Bf2hakw?si=guhMxX92T90aUkGy see this to understand the method
MIT grad shows the easiest way to complete the square to solve a quadratic equation. To skip ahead: 1) for a quadratic that STARTS WITH X^2, skip to time 1:42. 2) For a quadratic that STARTS WITH 2X^2, 3X^2, etc., skip to time 6:46. 3) For NEGATIVE leading term like -X^2, skip to 13:34. 4) If there's NO X TERM (ex. 3x^2 - 121 = 0), then you cann...
thnx
the bracket is being multiplied by 4
it might be easier to think about it as $4y^2-20y+25-25=-12x-67$ since $4y^2-20y+25=(2y)^2-2(2y)(5)+(5)^2=(2y-5)^2$
kheerii
(y-5/2)^2 = (-12x-67+25)/4
no
why
+25, not +6.25
but what you wrote has a term of 25/16, not 25/4
you're done, you can simplify the fraction
Ok
taking 4 common u get 4(-3x-42/4)
but this is incorrect
it should form (y-5/2)^2= -3(x+(7/2))
?
@twilit field ?
its not giving the same answer dude
sorry, was enrolling myself in a course
yeah, one minute
where are you stuck
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The extended Euclidean algorithm is an efficient way to find integers u and v such that au + bv = gcd(a, b). Using two prime numbers p = 26513 and q = 32321, find the integers u and v such that pu + qv = gcd(p, q).
I'm not quite sure how I'd do this, all I really know is that gcd(p, q) = 1
Good start. I would do pu + qv = 1
start with $1\cdot p + 0\cdot q = p$ and $0\cdot p + 1\cdot q = q$
Bonk
What does "start" mean here exactly?
What I'm confused about it how is the Euclidean algorithm relevant at all
this is the method i learned
you start off with those two equations
write them above each other
and then subtract them from one another until you get to 1
ill show the first step
one second
\begin{align*}1\cdot 26513 &+ 0\cdot 32321 &= 26513\0\cdot 26513 &+ 1\cdot 32321 &= 32321\(0-1)\cdot 26513 &+1\cdot 32321&=5808\-1\cdot 26513 &+1\cdot 32321&=5808\end{align*}
Bonk
do you see what i did here?
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,rotate
Hi guys any one have any idea how to do 13
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2. I have begun but got stuck midway.
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7. None of the above
I do not know how to start at all
I thought of integration
But my sch hasn't went through it yet only differention
My only thought process is coordinate q and r have same graident maybe we can link it to that
first try making an expression for the area of the rectangle
Hmm I'm not very sure how to do that
also, notice that it is symmetric around the x-axis
yea that makes it much easier
let x be the width of the rectangle
hmm yes so points q and r have same y coodinate right
then what would be height of the curve at that point?
no, x, but i think you get the idea
hmmm x/2?
not sure if thats a square if we js count the upper part
oops mb
where are you getting that from?
cutting the rectangle into 2 at the x axis
yes but we have the point x
on the x axis
what is then the value of the curve on the point x?
you know functions right?
yea
hmm yea
so this is a parabola
and the y value depends on x
now we have the curve x=y^2-4
then what is the value of y?
oh 2?
what?
how is y a constant
x is a variable
y is also a value
and dependent on x
im not sre i understand what do u mean by value y the value of y that makes x=0 or smth?
we want to find the area of the rectangle right?
hmm yes
so we need the width and heigh
we set the width equal to x
then what is its height?
im still not sure
what we want is a function of the area of the rectangle in terms of x
am i supposed to express the height in terms of x?
yes
i cant find any relation between the width and height tho
how not?
or is PS twice the length of QP
hmm but it only touches a side of the rectangle tho
so how do we involve the curve here
yes?
ur letting QP/RS be x right so im supposed to express PS in terms of x
so are u trying to releate QR to the eqn of the curve?
are u free now
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ye im gonna open a new channel
just asking if he's free or not
hmm is it sqrt(x+4)
x sqrt(x+4)
so ur saying as long as 2 points with the same x coordinate that touches this curve here it is always reprsented by sqrt(x+4)
wdym?
lets say p and s touches the curve too is the distance between them also sqrt(x+4)
ohh
for any pair (x,y) on the curve: x=y^2-4
i got d/dx=2x+4/2sqrt(x^2+4x)
or you can see it as: for any x and y that have the relationship that x=y^2-4, is on the curve
oh
formally: $C = {x,y\in\mathbb{R} :x=y^2-4}$
Bonk
anyway
,w d(x*sqrt(x+4))/dx
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Show your work, and if possible, explain where you are stuck.
you forgot an x on the 3rd line
oh my handwrigint mb