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so we must look at both the positive and negative cases :)
oh
nah nah ur good lol
i didn’t understand we were actually plugging it into y
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hi i was wondering if i could get help w these 2 tables. i thought i knew what i was doing but what i ended up with wasn’t right so if i could just get some help that’d be great
the definition of a linear function is that the slope remains the same
for the first table
can you find $\frac{Q_2-Q_1}{t_2-t_1}$?
PajamaMamaLlama
90.02-95.01/2-1?
@fast nest Has your question been resolved?
Result:
-4.99
PajamaMamaLlama
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✅
lol no worries
i believe this one is linear but i don’t know how to set up the problem to convert it to the equation
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im just confused on how to find the r(x) i know that 1/x^5 is the h(x)
@ember pelican Has your question been resolved?
<@&286206848099549185>
This is using the shell method tho right?
Not the disk method
Can't figure how what r(x) would be
ok what is r(x) and h(x) in this case
u draw a diagram
what variable is responsible as the slice gets closer and closer to b
this isnt really representitive of the area that u need to find
its underneath 1/x^5
above y=0
between x values
ok r(x) is x
it worked ;-;
honestly i probably shoulda tried that first since thats what it was for two other problems
thx
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find the ammount of odd coefficients of the expansion of (x+y)^1000
this is scary honeslty
Do you know how to find the coefficients?
yeah im p sure?
depends on weather i know the method your talking about or not
Do you have any useful formulas for the coefficients?
Formulas that maybe make it easier to check whether it is odd or even?
how about one involving factorials
checking whether a product is even might be much easier
dont know any
yes, thats the one, Binomial Expansion
ok
do you know how the choose function can be written with factorials?
uh its like n!/k!(n-k)!
yeah, so you do know how to write it with factorials, so the problem basically becomes determining whether this is even or odd
iirc n is the row and k is the thing from left to right or something
how can i do that?
I'll introduce this idea of a valuation, $\nu_2:\mathbb{Q}\to\mathbb{Z}$, it basically counts ``how many times 2 divides this rational number''
Element118
The relevant relations are $\nu_2\left(\frac{a}{b}\right)=0$ if both $a,b$ are odd, and $\nu_2(2k)=\nu_2(k)+1$.
(Exercise: Show that this is a well-defined function.)
Element118
can i ask what you mean with "times 2 divides" here means?
nmv im dumb lmao
if you had natural numbers, how often is 2 in the prime factorization
how many times (2 divides) this rational number
yeah that also is another way to view it
should have gone for an easier approach tbh, this valuation thing might be overkill
uh what can i do with it?
@raw jetty Has your question been resolved?
basically, for an integer, if $\nu_2=0$, then the number is odd, and if $\nu_2>0$, the number is even.
Element118
The alternative is to look at the power of 2 in the prime factorisation, and that approach is equivalent
so do whatever's more comfortable
hm yea this makes sense but im just not sure what to do with it
yeah maybe it's easier to work with prime factorisation
since the approach is easier
and equivalent anyway when you unpack it
you want to find the number of powers of 2 in the prime factorisation of $\frac{n!}{k!(n-k)!}$
Element118
I mean its not that easy with binomial coefficients. the answer is given by lucas theorem but I am not sure how that can be motivated well
and the proof does something completely different
uhhh sorry again 😭 but how do i find that?
so the subproblem is to find the number of powers of 2 in a factorial
if we can solve that for a factorial, we just need to combine the result for the numerator and the denominator to get the entire thing
its like floor(n/2)+floor(n/4)+.... right?
yeah, you know the answer
but it's not very easy to work with now
perhaps if we can write it as $n-$something we can make it easier
Element118
how do i do that?
find the "something" i mean
n=n/2+n/4+...+...
something=n-(floor(n/2)+floor(n/4)+...)
=(n/2-floor(n/2)+n/4-floor(n/4)+n/8-floor(n/8)+...)
={n/2}+{n/4}+...
might still be unwieldy, my next thought would be perhaps looking at the numbers in binary, there's a good chance that would help
since we have a lot of floor(n/2) and that's naturally shifting the integer in binary
what does {} mean?
pretty sure base 2 will help
fractional part
yep
the correct answer is expressed using the digits of base 2
we can always look at small cases to try checking for a pattern
well there is another way to write this... I am not sure if you want me to tell you that...
It's like not so common...
wdym?
write n in base 2
writing n in base 2, and k in base 2, then you may be able to see when n! has the same number of powers of 2 as k!(n-k)!
maybe look at doing k + (n-k) = n and think what happens if there are no base-2 carries in the addition
Show that when you write $n=\sum_{i=0}^ka_i2^i$ in base 2 where $a_i\in{0,1}$, we have
[\sum_{i=1}^\infty\left\lfloor\frac{n}{2^i}\right\rfloor=\sum_{i=0}^ka_i(2^i-1)]
Element118
(think about how the left and right hand side look like in binary)
sorry had s9mething to do
the rhs would like flip all yhe previous digits
the lhs would be uh
would it not be the binary representation of n?
wait no
ok wth im not seeing it
let n=15
7+3+1
111+11+1
1011
a_i from i 1 to 4 would be
1110
checking
1+3+7+0
huh how do i generalize it :(
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z^2 = 6i
I want all the z's
I assume there will be two since they are the roots
I forgot how to continue
sqrt both sides might be a good start
but after that it is a blur
z = sqrt(6i)
rewrite 6i as [(sqrt6)(cis(pi/2 + 2k pi))]^2
cis = cos + isin
its informal notation but used widely enough so i will just keep referring to it as cis
then naturally square root both sides to find the roots
then apply de movire's theorem and it should be complete
alright I will try to do that
Is that the same thing?
The cis thing confused me ngl
I also called k n instead
yeah but just make sure ur sqrt 6 is also squared
oh yeah
make sure u define n tho as an integer
i see that now
just out of habit
ok so hold on
for more formal exams or writings it should be expected for you to define n, the +2pi n is there for periodicity
ye i get i get it
let me correct it
or attempt to
If that is correct I can determine the value of cos and sin
because I know the angle
but how did you determine the angle was 90 degrees?
or pi/2?
out of practice ig?
Is it just because we say the complex axis is perpendicular to the real axis?
u can just evaluate it to show that it is i
or u can say complex axis is perpendicular like u suggested
so is the angle always pi/2?
im not sure i understand
so for normal roots of unity
liket say z^n=1
ur angle for ur RHS expression would be just 0+2npi
the angle depends on what u are trying to find roots for
In mathematics, a root of unity, occasionally called a de Moivre number, is any complex number that yields 1 when raised to some positive integer power n. Roots of unity are used in many branches of mathematics, and are especially important in number theory, the theory of group characters, and the discrete Fourier transform.
Roots of unity can b...
this might help if u want to have a read through
I am not getting the right answer
if x is a member of Z
sry
I mean if n or k is a member of Z
dont have to apologise
then cos(pi/2 + 2pi n) should be 0?
yes that is right
and sin(pi/2 + 2pi n) would be 1
yep
yeah then i have 0 + i
from this expression
wait
i^2
so -1
but uhh
that is not the right answer
oh i monkey brained
the trig expression isnt meant to be squared
just only the sqrt(6) is meant to be squared
should be
z^2 = (sqrt6)^2 * cis(pi/2 + 2kpi)
yeah it is but it is just for showing working out that u are setting up
there isn't really a formula , at least i was never taught one
i mean, u could generalise it to taking nth root as
z^n = r(e^(ix)), where x is some real such that r(e^(ix)) will represent ur RHS expression
show ur working out
yes and ur lhs is still z^2
Okay I am still confused
z^2 = 6i
z^2 = 0 + 6i
where a = 0
and b = 6
then I get the modulus of z
which is the same as r?
I think
again I am confused so I don't know
z^2=6i = (sqrt6)^2 * (cis(pi/2 + 2kpi))
=>
z= sqrt6 * [cis(pi/2+2kpi)]^1/2
=>
z=sqrt6[ (cis(pi/4 + kpi)]
That doesn't clear it up for me
I am turning it from rectangular to polar
You can do it in your head
I can't
|z| = r = sqrt(0 + 6)
so now that explains to me how you arrived at sqrt6
Assuming that is right
mhm ok lets just start over, i will try my best to show not skip any steps
z^2 = 6i = 6 [ cis(pi/2 + 2kpi) ]
De Moivres says z^n = r^n (cos(n theta) + isin(n theta))
if z = r cis theta yes
ok i will stop using it
I understand it is just the shorthand
for (cos(n theta) + isin(n theta))
well I say I understand
but I don't know
I assume that is what cis means
but I don't know
yes that is true
ok
so I put my sqrt6 into De Moivres
all my givens that I can figure out
z^2 = (sqrt6)^2 (cos(2 theta) + isin(2 theta))
then you said the angle was pi/2
I have no clue how you got there
i would avoid working out in your current order but i will xplain why in a few steps
for now, just to clarify
what demovire's is saying is just (cosx+ i(sinx))^n = cos(nx) + isin(nx)
let me wirte down on paper and i will just send an image, easier htis way
Given a complex number in rectangular form
no wait in this case it isnt a complex number, it is a squared complex number
this is so confusing to me
@heavy prairie my handwriting isn't the neatest in the world so lmk if anything is too difficult to read
@heavy prairie Has your question been resolved?
@heavy prairie Has your question been resolved?
ok
I rewrite it as z^2 = 6i + 0
i know
use z = a+bi
yes Daniel yes
<@&286206848099549185>
$z^2 = 6i = 0 + 6i = a + bi$\\De Moivre's Theorem tells me that $z^n = r^n(cos({\theta}n) + isin({\theta}n)$\\I don't know Theta or r, but to find r I can:\$z^2 = 0 + 6i\Longrightarrow z = \sqrt{0 + 6i} \Longrightarrow |z| = r = |0 + 6i| = \sqrt{0^2 + 6^2} = 6$\\I'm not sure how to find Theta.
Neo
You need to find the theta in the geometrical form of $z^2$
Lilly (NasaExploration)
Aka you need to normalize the vector and identify your sinus and cosinus then solve
So when you normalize you have $i$ because the norm of $z^2$ is $6$
Lilly (NasaExploration)
And then you will have $sin(2*\theta)=1$
Lilly (NasaExploration)
Then solve
I'm sorry but I can't follow that: I feel like I am lacking some really essential stuff, that, or people are just on a higher level of maths than I am at the moment.
I also feel like the language barrier is a problem because I had my whole math education in Swedish
I don't know what a geometrical form is
Should I just envision a square?
Yeah, would that be okay?
Actually let me pull up a whole talk I did about that form
Yeah of course
Firstly we will aim to explain what the trigonometric form of a complex number is. We will built it from the algebraic form you know
As you mean know, complex number are a thing (the only building element you need to know is that i^2=-1 which is weird but not too much if you think about it) and under their algebraic representation it looks like
z=a+ib
With a the real part and b the imaginary part. Noted :
Re(z)=a | Im(z)=b
You can also calculate the module of it :
|z|=sqrt(a^2+b^2)
This is a positive number and it would represent the length of the segment drawn between the origin of the complex plane and the actual point. You can easily realize that :
-|z|<=Re(z)<=|z| | -|z|<=Im(z)<=|z|
And therefore :
-1<=(Re(z)/|z|)<=1 | -1<=(Im(z)/|z|)<=1
What handy tool do we have to describe number between -1 and 1 ? We have trigonometric functions to do so. Therefore you can prove (here proving it is useless and likely out of your reach) that it exist a unique number theta in between 0 and 2 pi such as :
Re(z)/|z|=cos(theta) | Im(z)/|z|=sin(theta)
And this angle theta represent the angle between the segment drawn between the origin of the complex plane and the point AND the real axis (pointed toward the positive increment). Here I can’t really explain why as you don’t have the proof of it, it does explain a lot.
So you can write :
z/|z| = Re(z)/|z| + Im(z)/|z|i= cos(theta) + sin(theta)i
And us mathematicians can realize that writing e the complex exponential function such as :
z/|z| = e^(i times theta)
Makes a lot of sense as you can realize that it works nearly the same way as the exponential function. Every single property of it applies to this view of complex numbers (except a few exceptions). Here I won’t go into much detail as it’s just a bunch of trigonometric properties you need to demonstrate in a very painful way.
So you have to differentiate the classic and the complex exponential function. It’s for their relative closeness that we kept the same notation.
So now it’s as trivial as multiplying by |z| to find the trigonometric form of complex numbers. It’s called trigonometric cuz at its core there is trigonometric functions. So :
z = |z|e^(i times theta)
Please note that this definition don’t work if z=0 as you would multiply (and divide when building it) by 0 and therefore don’t guarantee the uniqueness of theta. So the trigonometric form of 0 is just 0.
There a whole talk about it
We call it trigonometric form here because it uses trigonometric function
Okay I was confused about that
But I could replace trigonometric
with geometric
here?
So I get the geometric form of my complex number by rewriting it using euler's formula?
My complex number being 0 + 6i
Yeah and you aim to find theta
No no don’t use ln
You can’t use it there
yes ok i uhh dont know how to do this then
In here you found r right ?
Assuming I did everything correctly I would say so
Looking at it, it still looks correct
So I would say I found r
Yes
What value did you found ?
Okay nearly there
no way
I mean root square it
6 isn't r?
In your formula you have r^n which is r^2 in your case
I never ended up using that formula
I just want to get to use that formula
Oh wait
Oh you mean
Now I use that formula
and insert 6 into it
r is 6
but r^2 = 36
typo
Okay @heavy prairie I am sorry but I am not really free right now
Do you think we could talk about it in like 1 to 2 hours ?
I will be able to help you more cuz I would want to talk about it from scratch instead of losing you like that
Either here of DM I don’t mind both
I don't mind either way and yeah it can wait
Don't feel forced to help though, only when you have time and want to
I will close this in the meantime
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How to solve for L ⁉️
It means, solve for l, in terms of w and P
Say what now
I mean, try to bring l on one side of the equation
Okay so now I got -2W +P = 2L
———————
2. 2
Would I make the 2 cancel out the 2W?
Or just leave as -2W + P/2
Yes, divide both sides by 2. Because we only want the right hand side to be in terms of l only.
Okay so thoughts on -W + P = L
How?
What
I mean, if you are dividing both sides by 2, then the equation should be:
$-W+\frac{P}{2}=L$
moaforlife
You have to divide P by 2 too
It means that there are 2 things which have the same value...
And has a variable
And when we do any operation, we have to apply it to the whole...
Forexample
If we divided the right side by 2
then we have to divide the whole left side by 2
I know but I forgot 😔
So that it remains an equation...
Oh ok ok
So on the coffee question I have T = 5.50P +7F
What's it mean solve for F
And what would the constraints be
Solve for f, it again means, bring f to one side of the equation...
Like f=smt
And you have to manipulate what that smt is gonna be
Yeah but i would have T -5.50P = 7F
Yeah..
THEN?
you know what to do next...
Divide
Yep
But like
How?/
what?
Divide by 7 on both sides
yep
When it asks me to solve for F does it want me to have the $40 still
From a
Oh alright I just thought it would use more numbers
And then for the constraints. Does it just mean that like he has to choose what he wants more of?
rule: If they have not mentioned anything, you should never assume smt on own.
Also thank you for the help
Yeah no problem
wait..
So, by constraints, probably they mean, what can be the maximum and minimum possible value of p and f, when T=40.
Oh so like
"The max amount of coffee they can get is _"
Actually not really...
Is there any special way to solve the maximum value of P and F or do I just gotta mental math it kinda
If you read the question again, p is the cost of plain coffee and f is the cost of flavoured coffee
So, kind of:
"the maximum and the minimum value of both coffees that she/he can afford"
So she can afford 5 flavored or like 7 plain
Like that?
Alright I gotta go, thanks again
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Yeah you can simply make inequality by putting one 0.
My network is so bad... sorry I couldn't reply before...

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can sm1 solve this
<@&286206848099549185>
why dont u just do it
im stuck while adding the equations
show ur work
first i squared the 1ST equation then did the same with second
subtracted both
after that i got 4tanAcosA = m^2 - n^2
now i cant proceed
please help
thats value of m^2 - n^2
now plug values of m and n in the rhs part (4sqrt(mn))
you'll get lhs = rhs
yep
m^2 - n^2 = (tanA + sinA + tanA - sinA)(tanA + sinA - (tanA - sinA)) = (2tanA)(2sinA) = 4tanAsinA
u did something wrong in ur algebra
also yes, it should be sinA not cosA
yea sorry my bad
wait let me do that as you told
yea i got it
ty @gritty bramble@long axle

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How do i simplify this summation?
Hmm i dont see how to simplify it but seems like you can split it to two sigma sums
2 power n is summation of ncr coeff you can use that
and simplify
i did it
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Is this english or math 😕
Doesnt matter, put 77 outside
how are you "helper" (your role)
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think i got part of it now sigh.
I was confused on this for a very long time regarding how this is equal, my new understanding is that no it isnt equal.
but that c/a is still apart of the equation even if it is removed(negative)
and that because of that when inputted into the quadratic formula it would undo the negative and give the result for the normal equation.
is this correct?

Normal quadratic formula is
ax²+bx+c=0
Now if you divide everything by a you will have
x²+(b/a)x+c/a=0
Subtracting c/a both side will give you
x²+(b/a)x=-(c/a)
Where are you confused?
they are deriving it btw
nowhere shown
well sort of
i understand how they did this not how its possible
people tell me this is somehow equal to the original polynomial
but if polynomials are a bunch of components that make up the behavior of a parabola
wouldnt removing c/a alter that behavior
yes -c/a is still there on the other side but its negative
would that not then alter the behavior causing the parabola to be more flat or go in a negative direction since negative value was subtracted from the answer?
or by equal do they just mean when you solve it out via the quadratic formula it would become equal afterwords because the formula would undo it and generate the original quadratics answer?
Ummm why are you jumping in between parabola and quadratic equations?
Yes if you alter anything in parabola equation
It will change the graphs
are they not the same?
But solving a quadratic equation is a different topic than seeing parabola, graphs finding major minor axes etc
You can't say exactly parabola and quadratic equation is same. Quadratic equation is a type of equation, parabola, hyperbola, circle are well...
what are major and minor and how are they different dont you need the zeroes to find a parabola?
Idk the exact term to define them
The general formula for a parabola is y = a(x-h)² + k or x = a(y-k)² + h, where (h,k) represents the vertex
ax²+bx+c=0```
If you consider y=0, then parabola equation will change into a quadratic equation yes
Or x=0 for 2nd parabola formula
define Y
also define H and K
(their representations and meanings)
when graphing this what values would be assigned to X and what to Y (axis)?
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Guys this matrix would be
2-parameter solution?
i often read 1 parameter solution
2 parameter solution
but dont know what mean
it means this?
because of the 4th coloumn having unknowns which are not on the main diagnal?
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Functions f and g are defined from A to A, where A is a non-empty set.
If f(g(x) function is one-to-one which of the following is absolutely correct?
A)f is surjective B)g is surjective C)f is one-to-one D)g is one-to-one E)g(f(x)) is one-to-one
A video solution says:
If f(g(x1))≠f(g(x2)) then g(x1)≠g(x2) so g is one-to-one
But I didn't understand how other options can be false
@alpine sable Has your question been resolved?
<@&286206848099549185>
Based on the fact that it's just one-to-one you can't conclude it's surjective
Because it doesn't necessarily mean that every element of A is covered
So that's A and B gone
I am not sure I fully agree with the solutions
We can say that g(x1) = y1 and g(x2) = y2 and assuming that f(y1) is different from f(y2) it means that y1 is different from y2
Meaning that f is one-to-one
However with this information we don't know anything about g and thus we can't conclude E is true either
@alpine sable Has your question been resolved?
But f(g(x)) is one-to-one from A to A, so shouldn't it be surjective?
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Is this proof correct?
<@&286206848099549185>
@woven plaza Has your question been resolved?
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@waxen turtle Has your question been resolved?
<@&286206848099549185>
Is it 3-6 or all problems
prob all idk i haven tooled at the others
Do you understand the difference between jump and infinite
idek wat jump is
,w plot floor(x)
This is a example where it jumps
You can see it's constant for some time then it suddenly jumps upto 1 at 1
Ohhh
idek how to find that
is that like piecewise
Do you know about limits?
yes
Then take the Right hand limit and the left hand limit
If they're different then there exists a jump on that point
wat is infinite
and wat is removable and non removable discontinouty
i forgor
Infinity is when the function shoots upto infinity
,w plot absolute value of 1/x
Here at x=0
Function shoots upto infinity
am I doing like limits or sum idk it doesn't say lim
A removable discontinuity is when the RHL and LHL are equal and there's no jump
BUT
The value of the function is not defined or different than limit
Right hand limit
Left hand
I'll help 1st one then you try others
.
Yeah, since we see that the denominator can be zero we check there
x=3 is prob important
Take the RHL and LHL at 3
right hand limit it goes to infinity
Yeah
That'll be infinite I guess
Then the limit doesn't exist
There's a jump or more accurately a asymptote
Write infinite at x = 3
is that it
Yeah
I think it's neither
Removable would mean that we can define the function to equal the RHL and LHL so that it becomes continuous
It means that there are no abrupt value changes
Or there are no 'holes'
is this continuous
okkkkkk
Can you try the second one?
Lemme see
Yeah
ruh roh
i think i sold on my qui
quiz
on this
today
💀
i def said something like that was a remov disc
I think you'll be fine
Actually it maybe
I don't think my brain is functioning properly
I just woke up
You'll be fine
Anyways
There's another point you'll have to check
is it a remov disc or wat
Idk gimme a sec so you find about the other point in this
There are 2 points
heudhshsh
Where we check
5
I think it's remov discontinuity
Yeha
You were right..
Check on 5
okii
Try third
Try to make it a piece wise function
idk how
like
idk
idek how to solve absolute value functions
I was never taught
Look at the zeros of the function inside Abs Value
Those are the points we care
Recall
That Abs Value of x is x itself for x>0
And -x for x<0
help
So solve for when the function is positive or negative
?
wat does abs mean
Abs( x+ 2 ) = { x+2 for x+2 >=0
-(x+2) for x+2<0
Absolute value
..
oh the whole thing
Solve the inequality in there
do I include the bottom
That'll be the condition on x for the function to be x+2 or -(x+2)
or liek forget it
Yeah include it?
uhhh
so 4 and -4
idk
Ask
No
😮💨
The inequality is x+2<0
OH
Subtract 2 from both sdes
Do the other one similarly
x+2>=0
Yeah that's the other one
Both are pieces of the same function
-2
-2
oh
Yeah
but they r like the same thing
Do the other one too
No?
wdym i just did both
.
Wait how'd you get this
the second line
Solve those
Yeah
Everything less than -2
Yeah
Now write the function as piecewise
idk how
IDK
What's the function
-x-2 for x<-2
the initial function
That's piecewise but we want the piece wise of the initial function
So I ask you again
What's the initial function
Yeah
EZ
Now what's the resulting piecewise function
1
RHL and LHL
don't u just plug it in
No
Take limit
how
RHL and LHL
How have you been taking limits till now?
liek a month
Bro just take the RHL and LHL they're different
ISNT IT A STRAIGHT LINE???
IT'S NOT
-1
.
Yeah
Yeah
Try the next one
Yeah
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I wanted to know which one of the steps is wrong here. The correct answer is 1/6.
,rotate
Are you using L'hopital?
Yes, in the first step
Your derivative of the numerator looks wrong
I used sinx/x = 1 to delete the sin from sin(sin x)
I'm saying your derivative of cos * sin - cos is not correct
What would be the correct derivative?
Well, you'd use product rule for cos * sin, correct?
But it is not cos * sin, the angle of cos is sin x
Np
That just made me laugh
This solution was given for this question.
Oh, got it
Sin(sinx)/sinx wouldnt equal to 1 bcoz it is x tending to 0, not sin x tending to 0
But isn't it the same thing?
@trail imp Has your question been resolved?
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Who could graph the quadratical function: f(x) = -(x+3)^2+4?
Do you know what shape do quadratic equations make?
@unreal pawn Has your question been resolved?
yes, a parabola. Correct?
Yep
So, when it's -a, it just means that it's an upside down parabola
And you can substitute x values to find the corresponding y value to graph the parabola
Tho, there's a really great website for it. Search up desmos graphing calculator
i am asked to graph it, using the given formula. I did use graphing calculators, its just kinda unclear to me why it resulted in a -1 x-intercept
Oh, you can just substitute the value of y = 0 and find the x intercept
wdm
Here, put y= 0 as on x-intercept y= 0, right ? So, then you would get a quadratic and then you gotta solve that to find the values of x-intercepts
By y, I mean f(x)
Function of x is 0 on x intercept
I am so used to throwing around y's in place of f(x) to make the question easier, I didn't realize that it's not even a variable here
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Need Linear Algebra help; I've tried this homework problem a few different ways and still getting it wrong.
i would try reversing s and t
wouldn't s represent x3 and t represent x4?
thx alot
if we have that r represents x5 then it seems like it would make sense for s to represent x4 and t to represent x3
hmm didn't work but I'll ask my professor tomorrow morning, thank you though!
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My answer here seems to be wrong. The correct one is 1/6. Where is the mistake in the solution?
,rccw
how
I used sinx/x =1
sin(sin x) became sin x
In your work
How is that supposed to work
why?
i mean
firstly
where did u get sinx/x from
u didnt split the denominator
even if u do
its sin(sinx)
not just sinx
well, I have sin(sinx). so, I multiplied and divided by sinx and got sinx
what
That's not right
in your work, sin(sinx) became sinx out of nowhere
if u diviied by sinx, wheres the sinx in denominator?
also the x you took out of 4x^3, its still 4x^3 instead of 4x^2
in short its all wrong
no, like sin(sinx)*sinx/ sinx
so, sin(sinx)/sinx would become 1
and sinx would remain
oh
but the problem is
you dont put limit in between like that
its affecting the whole function here
the numerator has another term in addition
you cant do what you are trying to do
but dont limits have additive propertry?
what
like if you have lim x tends to 0 (x+y), you can put it as lim x tends to 0 x and lim x tends to 0 y
(x+1)x^2, if i multiply and divide by x, as in x*x/x, then cancel out the x^2 in numerator and denominator, this just changes the whole function
infact all these ^ steps are wrong
i see. then, do I have to lhopital all the way or is there any other way I can do this question?
except you didnt split or anything
u just multiplied by sinx/sinx (that too wrong)
if u have (x+1) and you multiply by x then the its x(x+1) not x^2 +1
yeah, i splitted and recombined them.
if u split them already then you dont combine them back
but why?
yeah but the denominator and the limit is still the same
but the function is changed
yeah, but according to the addtive property why does that matter
if the limits are same, I can add them
my basics do suck real bad so, I really need to clear these doubts
this was the solution provided for the question
yes
because using lhopital it will get complex
since you will have to keep differentiating until the indeterminate form goes away (so 4 times)
ok lets say you are right, see these 2 functions