#help-23
1 messages · Page 345 of 1
wait
its helpful to look at this, as this is your goal
x^2 + b/a*x + c/a = 0
(x+d)^2 + h = 0
x^2 + 2d*x + d^2 + h = 0
then all you want is to solve b/a = 2d and c/a = d^2 + h
try to do the completing the square part again
yup
this really hurt my mind
the best way would be to turn the coefficient of the second degree term to 1
then try to complete the square
that should lower your error rate i think
bro
how do i do it
tbh i can just ask my home teacher on saturday :(
i can only solve average quadratic equations but this no. I gotta ask my teacher cuz hes a master in math
hold up i messed up
do u mind if u solve it on a piece of paper and send me?
i asked google and chatgpt, both are the sames and idk how they do it.
We get:
d = b/(2a)
c/a = d^2 + h => h = c/a - b^2/(4a^2)
Hence:
x^2 + b/a*x + c/a = (x+b/(2a))^2 + c/a + b^2/(4a^2)
= 0
so
(x+b/(2a))^2 = b^2/(4a^2) - c/a
= (b^2 - 4ac)/(4a^2)
ur just confusing him atp
he doesn't even know the fundamentals of how to solve quadratics
based on what i've observed
I dont know how to read those 😭
oh my bad
@shadow cloud i think you should just use the quadratic formula
i know hot to solve but this no
that doesnt work
I only use (a + b)^2 formula and (a-b)^2 formula and a^2-b^2 formula
Another view on the quadratic formula.Full playlist: https://www.youtube.com/playlist?list=PLZHQObOWTQDP5CVelJJ1bNDouqrAhVPevHome page: https://www.3blue1bro...
here
it works but you cant blindly apply it
to solve quadratic equations
i dont think you have a good grasp on the basics
ye
U guys can giv eme a quadratic equation work and i try my way to solve it
This is not the quadratic formula for solving second degree (aka quadratic) equations
the video has some problems in it to
just pause and solve em
Sure, x² - 3x = 0
Hmm give me a work and i use the 3 formula
i think if you solve this youre very close to derive the quadratic formula
trust , just watch the lecture , you gain nothing from mugging up formulas you dont understand
in its generality
thats easy bruh
he's kinda close, he already tried to complete the square just that his fundamentals are really weak
x= 0. x=3
what is the square of 5/2
Well, what can I do lol? Better for you that I gave you an easier one 😅
remember (x+y)^2 = x^2 + 2xy + y^2
My home teacher havent teach me this but he teach me alot of quadratic equations that doesnt have 3x^2 or 4x^2
(radical 5/2)^2
i can write out the proof of quadratic formula for you if you want
ok how about i guide you through proving the quadratic formula
Ok
this also useful solving quadratic equation
its wrong tho, it should be 5^2/2^2
???
just cross it?
is the same way
you have x^2 + 5/4x
you want to complete the square
the square is (x+a)^2
i can solve that
(x+a)^2 = x^2 + 2ax+a^2
@jagged belfry what are you doing rn
equal 0?
your 2a = 5/4
bro what
so a = 5/8
write it on a piece of paper
a^2 = 25/64
where does the 2 go?
@jagged belfry gang what are you doing rn i dont wanna confuse him
ok you are messing up fundamentals indeed
are you just gonna continue ignoring me or what
@dusk gyro
yes
can u do it on a piece of paper?
yeah?
so like (x-5/4)^2 - 25/16- 36/16???
yeah
I have 2 math teacher
no
one is school teacher one is home teacher
yeah
@jagged belfry can u do the work on a piece of paper???
no its your job to do the work
I never use it
clearly ur not working time for me to take over
@shadow cloud where are you at right now
take a rest, sleep or walk a bit. you wont solve anything by force
vyasa add me 😭
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for (a), is it possible to break down M into smaller statements?
well, it is exactly as small as it needs to be
any smaller and you would need many more logical steps, and any larger in scope, and it would be difficult to even write the statement
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✅ Original question: #help-23 message
for (b), what should be my universe of discourse?
should it be the set of all people, or the set of all countries?
Well in this case, different quantifier quantifies different set
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"find out if these sequences are definitively monotone"
how the hell do i even approach it?
I'm pretty sure a montone sequence is one that either constantly increases , decreases or remains constant
yeah the definition is clear, im not sure how to actually prove it if it is or not
so just differentiate it and check if the derivative is always positive , negative or zero
if not then no
right
what is "differentiating"?
i should mention this is the first excercise of the course, so idk if we need to imply such black wizardry
this is also n in N
hmm then just try the values and check if the expression is constantly increasing or not
ohh that makes sense 
also what the hell is this? why is it missing the fraction line??
It's combinatorics
A combination, C(2n,n)
2n!/n!*n!
you can also see it as 2nCn
ye
I hate that notation.
right, ill take it as is for now
to get back on track, what do i need to do to say if a sequence like those are monotones?
definitively
"Easiest" way is if f(n+1)-f(n) is higher, lower or equal to 0
Actual easiest way is first degree differentiation, and compare the result with 0.
No
oh
You have elementary functions
just put in values and check in manualy
you dont need to diffrentiate here i think
manually... damn
I don't think that's accepted
i hope it doesnt come up on the exam...
hmm
it's a homework excercise not an exam drill so idk
another way to do it could be to check the sign of Tn+1 - Tn
that could tell you if it's a monotonous function
and it would be a valid method as well

i think
It is, but not always
It works if the function does not suddenly change how it works
i mean it is just a larger scale diffrentiation
but yes thats true
how do you check the sign of a function then? like let's say for 1/n
then it's 1/(n+1) - 1/n
so that's
... no i got stuck
1/(n+1) - 1/n
now simplify it
-1/(n+1)(n)
right
now the denominator is always positive
but the numerator is -ve
so it will always decrease
so it's monotonous
so the function is negative... okay i think i get this one, lets' see for another one
I solved the first one, it decreases, then increases
ye for values greater than root 10 its increasing
it needs to be definitvely monotonous, not monotonous
im pretty sure they are the same words
It's a very small change
For definitely monotonous there is a strict comparison, like greater or smaller
For monotonous, it's greater or equal or smaller or equal
It's the difference between > and >=
no thats increasing and decreasing
i think the professor explained it that "definitively monotonous is a function that is monotonous after a certain point and remains so"
ohh hmm
and monotonous is a function that is always monotonous
like, anything that isnt periodic is definitvely monotonous
More like, definitively monotonous, has no points in which the first derivative is equal with 0
by the way the method i gave you should work then in most of em
ok imma try it with the first one and see where i get stuck
just check n+10/n
leave the ^7
Because it is an exponential function
It has some properties
It increases if the base is higher than 1
no wait i didnt see the -
so the function is always decreasing in this case right?
so it's monotone
It's not monotone in N
Because you have the x in the denominator spot, for n=1, 2 or 3, it's smaller than 0, that would mean it is decreasing, but for n>4, it is increasing, that means it is not monotone in N
But it does not have the same behaviour in the entire N
You need the same behaviour over the entire N
no i there to be an n0 so that for each n>n0, the sequence a(n) is monotone
that's how the professor defined definively
Yes, but you have numbers that do not have this property
As long as there is a single counter, the definition would not stand
Keyword: each
again, it's not for the whole of N, only after a certain point is fine, like sin(n) would not be definitively monotone but |n-2| is, altho it's only after n = 2, but after that it's monotone for the remainder of N
like pretend this is a sequence, this would be not monotonous, but definitively monotonous
so it's monotonous after a certain point, that's how the professor explained it
this is translated
"we say a succession of variable sign is:
definitively positive if there exist an n0 so that a(n) > 0 for each n > n0"
so "eventually" it's postivie
you know what i mean?
yeah i just made is as example to demonstrate what i meant by defintively
i think it's better if i just call it "eventually"
it's eventually monotonous
that's what the excercise wants
sorry for the language barrier
the course is not in english so it's a bit difficult for me
It's only in italian maths I've seen the use of "eventually monotonous"
you've seen other examples of italian maths? or you mean just this?
Someone asked me a similar thing a couple of months ago
right that's... small world i guess
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It says prove the blue statement by repeatedly applying the purple statement to the green one
Please don't occupy multiple help channels.
The colors are messed up on my screen
Blue is above green and purple is the lonely one
I think I understood how to determine something like A^3 but that’s kinda it
Especially the part where it’s asking me to repeatedly apply it is confusing
Am I supposed to make up random values and bruteforce the rule? How is that a proof?
You mean the green one?
n will stay as n
yeah. take the determinant on both sides for the green expression
Determinant?
modulus
Sorry I’m not familiar with English terms
My prof isn’t doing a great job either to be honest
|A|?
They are referring to sets
oh then its different. then the bars around the A mean the size of the set
anyways if you do that. take the "modulus" on both sides of the green expression, then use the purple expression to simplify your right hand side
then you use the green expression again for A^(n-1)
and so on!
till n eventually gets reduced to 1!
Isnt the purple expression the left side of the green one tho?
|A^n|=|A×A^(n-1)| = |A| . |A^(n-1)|
look carefully. i used the purple to simplify the RHS
Rhs?
right hand side
Also did you mean = |A| * |A^(n-1)|
I still don’t really get how
|AxB|=|A|•|B|
==>
|A|•|A^(n-1)|
no the 1st doesn't imply the 2nd. we used the 1st to deduce the 2nd
its like say x + a + b =10 and a+b = 5
so we get x² = 25 but did we get x²=25 directly from a+b?
think abt it
No but it implies x=5 does it not
only if you're considering both expressions at the same time. not when you're considering one and not the other
How does this apply here?
Sorry I’m very slow
we had something of this sort on our right hand, right? :
|A × A^(n-1)|
then we used |A × B| = |A| * |B| as an identity
Identity?
say we assumed A = A and A^(n-1) = B
A^n= A•B
Is everything I can come up with
an equation thats always true
Like x=y without anything else?
Or just 0x=0?
this
This feels kinda pointless but I wrote this at least
I was hoping to understand something when doing that but no not really
see you're to prove the blue equation. so just forget about it for the moment. we can get to the blue just by using the green and the purple
Alright
1st two steps are okay
now for the 3rd step, use the purple for the right hand side only. forget about the left side. focus on the right
on your right do you see something like |A × B|
?
can you see that |A × B| is in a similar form as |A × A^(n-1)|
I meant the second part with |AxB|
I added the purple part on the right because I wasn’t sure if it’d be useful or not
Yeah because A^n-1 is now called B
yup!
so now you can write that part as |A| * |B|
but replace your B with A^(n-1)
can you show your progress?
Sorry I was writing
perfect!
So how do I prove it by repeatedly applying it?
Do I try smth like A * A * A^n-2?
now do you remember the original green expression? this time we're gonna use that as an "identity" but only for the |A^(n-1)| part!
can you see that A^(n-1) is similar to the from A^n
and from the green expression we know that A^n = A * A^(n-1)
It appears on the right side yes
so its pretty simple that A^(n-1) = A × A^(n-1-1)
and n-1-1 is just n-2
however do note that your expression is still between those bars. so dont forget those bars
no not like that. they are similar in the sense that they're both A raised to a power. whatever that power might be
Maybe fix my definition of B
note that the question stressed us to use the "original" green and purple expressions repeatedly
yup!
yes. so your B wil be the 2nd term
sure
can you see the pattern again? that this will be similar to the original purple expression
yupp now sub back in your definition of C
I thought I had it for a moment but this isn’t even what I’m supposed to prove
yess! exactly
I’ve changed it a bit
now the next leap in our logic is that n here is a natural number like 1,2, 3... its an arbitrary natural number so if we keep subtracting 1 from n for a long time, we'll run out. we'll end up with 0
nice. exactly what i meant to say
you can subtract 1 from a number n for n times untill you end up with 0
wdym?
This was only 20% or something of the second page
And the deadline is tomorrow
But I feel bad asking you for more help
You’ve been really patient already
?
its written at the end of Mathematical proofs to say "which was to be demonstrated" kinda like saying "hence, proved "
Ah I see
I’ve honestly never seen that
Maybe it’s not used in Germany
To be fair I started my lectures like 5 minutes ago
Today was my sixth day
i see
damn you've a lot left 😭
I mean it
I’m going insane
And I need to submit this HANDWRITTEN and per MAIL
My professor is an idiot
yeah. im sort of heading off now. but if you have any doubts in the future man, just dm
Id highly appreciate it
Is it fine if I add you?
sure!
damn thats crazyy 😭
You did a lot tho
Thank you
no worries 👌
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In the Simplex Tableau Method (Linear optimization), we generally move along the borders of the domain to get to the next vertex.
From what I understood, the basic direction is the one corresponding to the variable entering the basis. So in the image attached,
it would be (1,1) as x1 will enter the basis. However 1,1 in this case, if you represent graphically, goes INSIDE the domain and not on the border to the next vertex.
Why is that so ?
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f(g(x))
3sqrtx^2 +2x + 3 -2
3sqrt x^2 + 2x +1
now i replace x by 3? to determine the value?
You can simplify it even more
how
= 0?
Yeah, you can do that
Id advice you use the quadratic formula
what is it i forgot sorry been a year
$\frac{-b\pm\sqrt{b^2-4ac}}{2a}$
∫ᴄ 𝐅·𝑑𝑟 = ∬ʀ ∇⨯𝐅 𝑑𝐴
Twice, right?
yeah
I hope you remember that you can use this formula to also factorize a quadratic
ill remember
So, if you have the same root twice
Youll have two equal factors, right?
(x+1)(x+1) here, right?
yeah
it is
So:
$x^2 + 2x + 1 = (x+1)^2$
∫ᴄ 𝐅·𝑑𝑟 = ∬ʀ ∇⨯𝐅 𝑑𝐴
Knowing that, go look back into the problem we had
$3\sqrt{x^2 + 2x +1}$
∫ᴄ 𝐅·𝑑𝑟 = ∬ʀ ∇⨯𝐅 𝑑𝐴
So how would that end up looking like?
3(x+1)
wait but why did we have to do the quadratic thing
just for practice?
wait how did u know it was (x+1) and not like (x+3) or something @split kayak
like why 1
alright
for any given quadratic polynomial of the form $ax^2 + bx + c\$
you can also write it as $(x-x_1)(x-x_2)\\$
where $x_1$ and $x_2$ come from the solutions of $\frac{-b\pm\sqrt{b^2-4ac}}{2a}$
∫ᴄ 𝐅·𝑑𝑟 = ∬ʀ ∇⨯𝐅 𝑑𝐴
oh so (x -(-1))(x-(-1))
You can always rewrite a quadratic as the product of (x- (the roots))
Since this polynomial is a perfect square
gotcha
gotcha
btw this gives (x+1)^2
Yes, thats why i knew that the polynomial became (x+1)(x+1)
Yes
gives 12
Yep
Yeah, you could write down the calculation of it
what is it
when you do $\sqrt{(x+1)^2}$
∫ᴄ 𝐅·𝑑𝑟 = ∬ʀ ∇⨯𝐅 𝑑𝐴
∫ᴄ 𝐅·𝑑𝑟 = ∬ʀ ∇⨯𝐅 𝑑𝐴
so its |x+1|
For this particular case it doesnt really matter since x is > -1
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not sure if this counts but what even is this?? I’m actually really curious and have found nothing online
this has to be gibberish
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How do you rigorously prove that for a continuous 1 to 1 function f over [a,b]:
f^(-1)'(y) * f'(x) = 1
I mean it's intuitively obvious
But like?
I'm sure I did some illegal operations somewhere
Well show what you did
yall know about quadratic equations like finding roots and vertex??
@astral glacier
This is my channel lol
yea I was wondering why that person was there
i need help with understanding the steps it confuses me with inequality stuff
alr!
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@still charm Has your question been resolved?
I think its legal if you show or mention that from continuity of f^-1 it follows when f(x)->f(c) then x->c
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Does anyone
Alright, gotten
.close
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x^86=6 mod 29
did you perhaps mean (x - sqrt(6)) (x + sqrt(6))?
from here you can probably do a quick check of single-digit squares to see if they leave a residue of 6 mod 29
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uhh well my question is how to find an equation of a plane using a line equation and a point(x,y,z), and how do you find a equation when two planes are intersecting along a common line
equation of a plane using a line equation and a point(x,y,z)
this first, you can assume the equation is ax+by+cz+d=0 and then find the relation for x,y,z from the line equation
assume for the plane yes and what if the line's given in vector form
a line and a point do not determine a plane
ehh doesn't matter really
It does if the point does not lie on that line
but in cartesian form a point's already given so wouldnt we use that
im kinda lost in forms of lines
how many planes pass through a given line?
uhh infinite
yes
but since a point's given, we assume a general point and find direction ratios
is that basically it
idk what ur saying
sub in points that lie on the line into the plane equation
and find relations between a b and c
uhh but we're not sure if the point is in the plane
can we do that
you have to find such a plane
i.e. u have to find a,b,c
yes because the line lies on the plane
same thing bruh
yeah u just sub in what ur given
ohh sure mb
uhh how about my other question
equation of a third plane i mean*
2 planes intersect don't determine a plane
yes but how do you find one passing through the line of intersection
is there a formula or?
aren't you already given two
If it is it would be lengthy
yeah but we need a new one
oh
maybe like the find the general equation of a plane that passes through that line
so basically it depends on the question
Yeah, find the line of intersection and then do what we did for the first part
ohh alright
uhh for my final question, its a test question which had me confused for like a couple of days
you can find 3 edges AB,AC,AD using areas given
im lost as to how
we take the dot product of the pv ?
nah
ABC, ACD and ADB are right triangles at A
Do you know what mutually perpendicular mean
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,rccw
yes, the helper earlier already confirmed your answer
unless your doubt is something else, in which case please raise it now
@cobalt saddle
Just kinda bullshitted my way to a answer
So i do not really know how i got it...if that makes sense
first, show your method, bullshit or otherwise.
then we'll see if there's merit to your method that you just didn't get, or it's a lucky shot.
ok, and what was your reasoning for this calculation?
See that is the problem...
I mean, surely you have at least some idea of what you were doing, right?
it's ok if it sounds weird or wrong
we can work with that
(who knows. maybe your reason is actually correct)
Ok...well i divided the possible ways to allocate three people from a group of eight to the three positions by three people who must serve in three different positions to be left with left with possiblities where position is irrelevant?yeah i do not know what i am doing
and you got those answers from (1) and (2), yes?
🙌
Yeah
and that is the right reason
Do you know permutations and combinatorics
But again i do not know what i am doing
when doing (1), you care about their positions, but in (2) you found out how many different arrangements a given group of 3 can make
so if (1) picks out a group of 3 from 8 where we care about the different arrangements a group of 3 can make, and (2) gives us the number of arrangements any given group of 3 can make between themselves, then it must follow that if we don't care about the order, you can just divide by the number of arrangements any given group of 3 can make to cut down on the overcounting
and that's really it
Ok...thank you
nps. anything else?
Other question or...
whatever. it's your channel
well, of course they must be questions
this is a help channel after all
I would recommend not sending random gifs in a help channel
This is a question i wanted to with yesterday
I want to understand it
Kinda used bullshit again
Are you sure i can ask again?
why would I tell you to if you're not allowed to?
Ok...
though I will be doing other stuff for a bit, so you can ping Helpers once now if necessary
Ok,thanks
@cobalt saddle Has your question been resolved?
<@&286206848099549185>
<@&286206848099549185>
What
This
Let me do it rough
I only require a explanation
Nah I'll give u the soln
I'm done
Just wait a second
% 📘 Hotel Revenue Optimization
\textbf{Given:}\[4pt]
Total rooms = $72$, \quad Base rent = $R500$ per room.\
If rent increases by $R100$, ; 2 rooms become vacant.\[6pt]
Let new rent be $x$ ; (where $x > 500$).\[8pt]
\textbf{Rooms occupied:}
[
N = 72 - \frac{x - 500}{50}
]
\textbf{Total income:}
[
I(x) = x\left(72 - \frac{x - 500}{50}\right)
]
[
\Rightarrow I(x) = 82x - \frac{x^2}{50}
]
\noindent\rule{8cm}{0.4pt}
\textbf{Differentiate:}
[
I'(x) = 82 - \frac{x}{25}
]
Set $I'(x) = 0$:
[
82 = \frac{x}{25} \quad \Rightarrow \quad x = 2050
]
\noindent\rule{8cm}{0.4pt}
\textbf{Second derivative:}
[
I''(x) = -\frac{1}{25} < 0 \quad \Rightarrow \text{Maximum at } x = 2050
]
\textbf{Maximum income:}
[
I(2050) = 82(2050) - \frac{2050^2}{50} = \boxed{R84{,}050}
]
\noindent\rule{8cm}{0.4pt}
\textbf{✅ Therefore:}\[4pt]
The hotel achieves a \emph{maximum daily income of R84,050} when\
the rent per room is set at \boxed{R2050}.
ÆΣρx
Thank
.close
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I'm stuck here
,rccw
It's the 595 one (prove that the equation ex-1 = cosx/x has at least one root)
Idk if root is the right word for this but I mean that it touches the x'x line
Also it's e×
I doubt that anyone here speaks Greek.
x is a power
I translated good sir.
I have to solve this using Bolzano's theory right?
Oh wait it's cosx
@cobalt wedge Has your question been resolved?
Can someone help 🥺🥺
Bawwww
@cobalt wedge Has your question been resolved?
Define f(x) by manipulating the given equation to equal 0, then determine f(0) and f(1) and apply IVT/Bolzanos Thm
Also show the f(x) you obtain is continuous but this is straightforward
Is that not what I've done?
My bad, didn't realize you already posted an attempt ; though your f(x) seems to be incorrect
It's just I can't find a solution for f(0) cause cos0/0 equals 1/0
You can multiply x to the other side first
Which gives you xe^x -x = cos x
And then subtract cos x from both sides and continue as before
.solved
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hi im trying to answer this, but im not sure if i am doing it right. for the first part which involves the operations (a) and (b), i deduced that it is always possible, since if we have m<n, we subtract m-1 from both sides, such that we get 1 and n-m+1, and then we can keep doubling 1 until if we double one more if becomes greater than n-m+1 (2^a < n-m+1), in which case we keep repeating the process of slicing both down to 1 and another number, eventually when we slice both numbers, one will be 1, and the other will be a power of 2, hence, we can double 1 up to that power of 2, and then slice both to 0. although, i don't think its possible with 3 balls, since u may be left with the same method, as you may be left with 1 in one bag, and 2 in the other bag, in which case its impossible afterwards? i was wondering whether this is right, and if this can be written more mathematically? thanks🙂
@native flume Has your question been resolved?
for the second one you can find a simple invariant
not sure what that means
a quantity that doesn't change when you apply the operations
then you know when a state is impossible to reach if that quantity changes
in this case it has to do with the parity of a certain value
for the first question, your algorithm probably works but that would be tricky to prove I think. There's an easier method if instead of trying to reach 1 ball in one bag, you try to make it so the second bag has exactly double the amount of the first bag
ok il have a think thanks for ur help🙂
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@slender cloak Has your question been resolved?
<@&286206848099549185>
You should really write e.g. the second line as [\mathbb P(A\cup B)=\mathbb P(A)+\mathbb P(B)-\mathbb P(A\cap B)] and similarly everywhere else you're using $+$ or $-$
Edward II
Saying $A\cup B = A+B-X$ is meaningless; you can add/subtract the probabilities of the events but not the events themselves
Edward II
this isn't as simple as just putting Ps in everywhere by the way, since you're using these plus minus inside P in the sixth line, which you'd need to resolve
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Hi, is this correct?
you duplicated negative signs
(a-b)^2=a^2-2(a)(b)+b^2
The term b is negative
but we've already account for the negative sign on the middle term, in fact: ((a\pm b)^2=a^2\pm2ab+b^2)
ΠαϳαμαΜαμαΛλαμα
where (\pm) can be plus or minus
ΠαϳαμαΜαμαΛλαμα
Ok ty, and does this applies to more formulas?
Depends
How can I know which formula follos this rule and which one not?
One example is $a^2 - b^2 = (a - b)(a + b)$
1 divided by 0 equals Infinity
The plus version of it does not have a formula
Why not?
Ok nvm
But is there any rule or any formula can have any rules?
To figure out which formula corresponds to which
Just expand
For example: $(a \pm b)^2 = (a \pm b)(a \pm b) = a^2 \pm ab \pm ab + b^2 = a^2 \pm 2ab + b^2$
1 divided by 0 equals Infinity
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i understand the proof except some part
this part
i dont understand how all other matrices from the cofactor contain exactly k-2 times the polynomial variabele x
@ocean hamlet türk müsün?
evt
@ocean hamlet Has your question been resolved?
@ocean hamlet Has your question been resolved?
bc the x variable is only on the diagonal
so no matter which row or column you cofactor across, there's only one x in the chosen row/column. and that x will only be multiplied to one of the determinants when you cofactor
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I think it wants you to rewrite sec and csc as their 1/…
Then use cos(x) = sin(90-x)
you should have something like sin(...)=sin(...) after this
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|x| is continuous, and |0| = 0
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helloo
ive tried factoring it out
$$\frac{a+b+c}{d} = \frac{a}{d} + \frac{b}{d}+ \frac{c}{d} $$
Ryne___np
actually factoring works here too, what did you do exactly, so we can check your work
or, more concretely, what issues are you even having?
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genuinely how do i do these? i have a general idea but i’m just lost on the one with the square root and the fractions
do you know the chain rule?
No wait what is that
when you have a function inside another function, there's a particular rule for finding the derivative of the expression (you need it for the square root)
the general form of the tangent line:
y = f'(x0)(x-x0) + y0
the derivative of $f(g(x) \text { is } f'(g(x))g'(x))$
Gizmic
or alternatively, $\frac{dy}{dx} = \frac{dy}{du} \times \frac{du}{dx}$
Gizmic
depending on your notation
for the fraction you then also have the quotient rule!
however, you can also write it say as $\frac{-10}{1-x} = -10(1-x)^{-1}$ as well
Gizmic
Ohh
Thst makes sense
To gwt the general answer we usually rewrite it similar to that
Its something along those lines
But for normal ones we use a formula
Its like f(x-h) - f(x) / h or something
isn't this the first principle definition of the limit?
yeah sure
yeah this is the derivative from first principles
for normal functions you shouldn't have to use it
this is more something you use at the start of calculus to justify the derivative for some simple functions
but the rules like power rule and stuff can just be used instead if you're given them
We went over it lightly in the beginning but he barely soent five minutes on it
Differwnt rules and stuff
Thank u so much though U helped lots
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I need help with geometry and finding x for supplementary and complementary angles
It’s number 11 but idk how to crop on here 😭
Oh I forgot to add the 180
Same idea for the second part, but = 90 instead
okay
For the first one I got 10
And for the second I got 7
I do have one last one question
how would I solve this one
Do I subtract 180-75? Since it’s a straight line
yeah
do you know the relationship between angle theta and the angle 7x
there's something special about all of these angles
Vertical pair?
yes, vertically opposite angles are... ?
ohh congruent
since you already know the angle that's supplmentary to the angle that's 75 degrees, which is 7x...
there's two other important facts:
- alternate angles are congruent
- corresponding angles are congruent
thank you 🙏🏾
is that the 105 I got?
and corresponding angles are just vertically opposite angles, then alternate angles
yes, 75 is supplementary to 105
yeah
a good thing to remember is that you can find one of two angles that are supplementary by subtracting the other one from 180
okk thank you
no worries! if you're done for now, type .close
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hello people
you can usse isosceles triangle properties
huh
suppose there is a triangle ABC s.t. AB = BC (their lengths are equal), this implies the angles BAC and BCA are equal
try to find a way to show that EFG = EDH, also show that EHD = EGF
the rest should be easy
hm
hint : EDF is an isosceles triangle
ohhhh
What did you conclude?
Didn't you prove it by SSS test?
how did you get dg=hf
alright bro
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So for this problem I know that the area formula is A = 1/2absin(C). But I'm confused about angle C. Why is the supplementary angle of 28 degrees used for C and not 152 degrees?
Idk if this question makes sense
tbh no clue but sin(180 - theta) = sin theta , so its all good
So you don't know why they are using 28 degrees for C?
As opposed to using 152 degrees
... a better question would be: why is the 4 m measurement not used here
smaller number looks friendlier. otherwise if you're using a calculator it won't make a difference.
Yeah, maybe my professor messed up the answer
So the two angles are interchangeable?
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What am I able to do, I recognise that when I fix a partition, the Upper sum of f2 >= Upper sum of f1,
how can I show that the inf Upper sum of f2 >= inf Upper sum of f1
@uneven veldt Has your question been resolved?
show that "inf upper sum of f1" is a lower bound of the set of upper sums of f2
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confused, unsure where to start and how to continue. Finding the value of X
google log rules
not sure what u need help with
unsure of what to do for the next step
do i sqr the x^2 and 48x
The cube root can be also expressed as ^1/3
ohhhh
Well you didn't say it outright

So I'm just saying it outright
thank u
yep
i think i got it!! thank you guys
是的
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はい
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I am not getting it help @everyone
you can't ping everyone man
@everyone help me plz tm I have exam
Please don’t do that, after 15 mins of the help channel open you can ping the helper role ONCE
we cant see the entire question
or can we idk i dont see a question mark 😭