#help-49
1 messages · Page 33 of 1
@last slate Has your question been resolved?
Give me a moment while I help someone else first.
okkk
Ok, so when you encounter a situation as you did with y = 0 and lambda = 1, treat them as two possible cases.
.
Alrr
That seems to be where you got stuck anyways, am I correct?
So you have the case of y = 0. Given all of the equations you came up with and were given, which ones could you use that with?
The constraint equation?
Yes.
But wouldnt that only give me that -xz = 64
Sorry for the wait, I just needed to verify what I was doing.
Now use that result in one of the other two lambda functions you found to solve for either x or z.
yw
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DE
arcsin(y'') = x(y')
why is degree not defined
can we just say
if the argument of trig funcs got derivative inside , the degree is always negative
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f'(0) is defined because from the left, we have 2(0) + 2 = 2 and from the right, we have 2
So the limits from the left and the right are equal
We're using properties of continuity here since we are given that the function represents f'(x) already
(and when x = 0, we have x >= 0 for the top branch, so the limit equals f'(0) = 2(0) + 2)
For the second image, the slope of the graph is clearly different from the left and right of each jagged point
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If a set of eigenvalues containing n eigenvalues has some non-simple elements, does that mean it is not possible to form n linearly independent eigenvectors from that set?
by "simple" I mean each eigenvalue having an algebraic multipicity of 1
you mean linearly dependent eigenvectors, i assume?
yeah edited sorry
no, it does not necessarily imply that
for example, the identity matrix has only 1 for an eigenvalue, repeated n times
and every nonzero vector is an eigenvector
so you can take the standard basis for example
what you're asking about is the geometric multiplicity of the eigenvalue, as opposed to the algebraic multiplicity
you always have GeoMult <= AlgMult for each eigenvalue
GeoMult is the dimension of the eigenspace associated with the eigenvalue
so the situation you're asking about is when GeoMult is strictly less than AlgMult
which can happen
for example: $$\begin{pmatrix}1 & 1 \ 0 & 1 \end{pmatrix}$$
Bungo
1 has AlgMult 2, but GeoMult 1
right, so i guess in a way like
you can have an eigenvalue repeated 5 times for example
but maybe u will only produce 3 linearly independnet eigenvectors from those eigenvalues
yep that can happen
so that eigenvalue has a geo multiplicity of 3 and the eigenspace (the space formed by the span of th eigenvectors) will be of dimension 3
correct
like do they span R^3 or is it entirely different
they span a 3 dimensional subspace of whatever R^n they live in
at some point you'll learn about the jordan canonical form
which puts the matrix into a form where you can see at a glance the whole structure
you can see what are the eigenvalues, and what are their algebraic and geometric multiplicities, at a glance from the JCF
But wait just to conclude
For my original question
considering our set, assume we have only 1 element with an algebraic multiplicity m, with the rest being simple, and no knowledge of what the geometric multipicity of that element is
then we can assure ourselves of there existing at least n - (m + 1) linearly independent eigenvectors right?
since i assume each eigenvalue needs to have at least one linearly independent eigenvector
well if there are a total of k distinct eigenvalues then you're guaranteed at least k linearly independent eigenvectors
right
since eigenvectors associated with distinct eigenvalues are linearly independent
(if the matrix is symmetric then you can even choose them to be orthogonal)
right
and what about the case i mentioned? like with onlu one non-unique eigenvalue
haha let me do the arithmetic in my head, i'm working with 2 sips of coffee so far
1 eigenvalue with algmult m, the rest are simple, so you have n-m other eigenvalues, and a total of n-m+1 eigenvalues including the first one
so yea
at least n-m+1 LI eigenvectors
n-m+1, not n-(m+1)
haha no worries sorry about that
okay gotcha! i think i understand this topic now
much appreciated bungo
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sure
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I have to write it as one log but im not sure if my answer is correct. My answer is 3log(9x^2)
can you show your work
yes give me a second
what laws are you applying to get from the second to third line
you don't quite have that here
apply power law to the
$$\frac{\log_{3}(y)}{2}$$
ℝαμΩℕωⅤ
How does the powerlaw apply here
what does the power law for log say
isnt that just for multiplying
wdym
@regal dome Has your question been resolved?
no
before you do something, state the specific law you are trying to apply
also state the power law i recommended you apply earlier
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correct or nah
correct
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are there a total of 4 possible answers to this question?
depending on which pivot you choose
or are there infinitely many solutions
or maybe there is only 1 solution? i went with x1 as the obvious choice for the pivot, but i haven't learned about column operations yet, only row operations (RREF)
I suppose RREF is not even needed here, with only 1 row
so i'm gonna guess infinitely many basis, not just 4, but what do you think?
and if that's true, i wonder how WebWork can check this, if there are infinitely many answers
@echo perch Has your question been resolved?
indeed there are infinitely many bases here
hopefully they have some custom computation behind the scenes to check that your answer is actually a basis
you could try and see if the site is good or not
try and replace the first vector by [-1 1 1 0] (added the first and second vector together, the span doesn't change)
interesting
to be "proper" basis it doesn't need to have a single "1" for each pivot? for each vector
in terms of the actual math (not WebWork), it doesn't matter, it's still the same basis, just a different way to write it?
well no it's a different basis obviously
they describe the same vector space though (ie the vectors (x1, x2, x3, x4) for which 7x1 + ... = 0)
oh right, different basis but to describe the exact same vectors
i look at basis as conversion system, like an oven that is F and an oven that is C
both get the same result if you follow instructions for temp and time
so changing the basis is like putting a skew filter in photoshop onto a vector grid system. the grid lines still match up to the vectors, they just look different to the naked eye
3Blue1Brown has a great video on this
yes, that's exactly where i got this analogy from 🙂
helpful to understand basis
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hello !!
i kinda need some help on this cuz i really dk how to approach it
got this from somewhere as well so yea
<@&286206848099549185> a
i guess i found the area to be 18 using geogebra but how i actually prove it
i know it forms 3-4-5 triangle but is it just a coincidence??
@sage knoll Has your question been resolved?
@sage knoll Has your question been resolved?
@sage knoll Has your question been resolved?
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hi
Ello
this is grade 9
I never learnt about a zero product
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thanks
.reopen
✅
Aren’t u just finding the zeros of the factored equation?
yes
So what do you not get?
idk its confusing
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that's not correct
i thought with jump disscontinuity the x does not exist
that is if the question asks for the limit as x->1, not 1+
If it was minus it would mean end behavior on left side
yup
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What aspect of this question do you need help with?
maybe some factorization will advance the problem
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How do I even start?
Look for dilapidated idols
Yeah
ahhhh
Here is the geometric reason
The reason we do b/2 is so we can form the two rectangles, which gives the edge lengths of the bigger square we add
,rotate
wdym
if ur doign the slide and divide thing yeah
is my answer correct?
wait nvm it is
if its like can be divided by the first number then it will be fine but if its not then i would multiply the first number by the end number
ye
You need to multiply by 2 though if u only have (x-2)(x+1) as the final answer
since that is only x^2-x-2
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Where did r/h from
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Hint:
Cut it into triangle
Then get one triangle's area then multiply with 6
Fun fact
Just use sss after finding angles
Dont hand it out for him
He should figure it out himself
Then whats the height?
.
Area of Octagon = 6 * one triangle
No?
Show the work of how u calculate the height
Use pytha theorem is much faster
Google use radian
not degree
So sin60 = sqrt(3) / 2
Is it?
Even that
Google calc gives out decimal number
Well, u can use whatever u like
Wdym
Look
See the green triangle
Use pytha on it
U can only use pytha for right triangle
No
Whats the pytha theorem states?
Whats c?
Whats a then
💀
Dude
You need a lot of practice
That is a very terrible way of doing math
Any teacher who endorse this way of thinking shouldnt be a teacher\
b is the height
Did ur teacher only teach Pytha theorem to calculate the hypothnuse
get a new teacher then
b is the height, so set b as a variable
plug in c and a
Then find b
GOOD
Now get b
Is a calculator too expensive for u? Cause having one is a must if u want to be good with math
Yep
now get one triangle area
*6
Then u get the final answer
Thats weird
Oh yeah thats correct
My calculator = 216V3
= 374.1229744
Nope
@last slate
Theta is in radian
Not degree
U can convert from deg to rad by :
Rad = Deg * pi / 180
So 120 deg = 2pi/3 rad
Its just a number in an unit
If u haven't learnt it
U could think that Area of the arch = x * area of Circle
Where x is just a number, and u need to find it
Hint: ||It has to do with the angle 120 deg||
No
Whats the angle of the whole circlce
Ok
here's th way to find x
If 360 deg = the whole cirlce (100%)
Then 120 deg will take up how much percent of the whole circle
Hint: ||Triangle method||
Yep
So that area will = 33.333% of the total area of circle
33.3333% is just 1/3
Multiply
33.3333 percent
No 33.33333
33.33333 percent = 0.3333333 = 1/3
Yep
Good job
Remember the unit
cm^2
.
what is this?
This is the correct answer
u just need to plug cm^2 at the end
Oh
No
Sorry
U can use the same method to find the arch length
Since 120 deg take up the same percentage of the whole circle arch so just 1/3 * whole arch
Yeah
@last slate Has your question been resolved?
angle 3x+10 and 6x-28 create a line, or a 180 degree angle, which means 3x+10+6x-28=180
do you know how to continue it?
@last slate Has your question been resolved?
$$3x+10+6x-28=180$$
$$9x-18=180$$
$$9x=180+18=198$$
$$x=22$$
Skill_Issue
do you know how to continue this for y?
former
Its Cadet Time
no
you can see that its an icoseles triangle, with the base angle being 3x-35
so 2x+2+3x-35+3x-35=180
and continue from there
yes since its a triangle
Its Cadet Time
no afain
use this
here i labeled it for convenience sake
AB=CB, which mean BAC=BCA, the inside angles all add up ti 180
ABC+BCA+BAC=180
we know that ABC=2x+2
BAC=BCA=3x-35
which means 2x+2+3x-35+3x-35=180
well BA=BC=18
do it yourself :p
show your work
it should've been $$ 2x+2+3x-35+3x-35$$
Skill_Issue
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consider the cases for x > 1 and x < 1
the lhs is just absolute value
you could but this is not good idea
consider what happens to sqrt((x - 1)^2) when x > 1 and when x < 1
only when x > 1
misunderstanding here
sqrt((x - 1)^2)
say u just allows this to equal (x - 1)
then for x = 0 or something, this would be -1
so you are essentially claiming that sqrt((0 - 1)^2) = -1
but a square root can't be negative, so there is something wrong with this reasoning
also no
to get around this, we take note of the following: (x - 1)^2 = (1 - x)^2
does it make sense why this is true
consider: (x - 1)^2 = (x - 1)^2 * 1 = (x - 1)^2 * (-1)^2 = ((-1)(x - 1))^2 = (1 - x)^2
cool
uhhh
probably?
anyway basically that is how we split the expression into our x > 1 and x < 1 cases
and to complete the problem, you solve two inequalities (one for x > 1, one for x < 1)
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Let f(x) = x^3 + 5x -10
f(x) is continous throughout R
Then x0 is the root of f(x) if a < x0 < b and f(a)*f(b) < 0
In other sense
wdym by this... kinda complex notation that we havnt gone over
in my class
howcome you know that the cubic is on the positive side of the x axis?
This is just a visualize,
oih ok
The point is, this is always truth for any graph
so what next?
i do
but how do i find the points
oh
just checked the answers
only one is opposite signs]
These are a and b
b
this is f(x)
Yeah, find the actual root
yeah
The point is, your teacher probably set it so hard to find to root, thus force u to use this
oh ok
so how do i use that
u said the signs must be opposite
but the answer is not b
so keep doing that until you get opposite signs
YEP
Yep
therefor in between is the x int
yep
but its pretty easy to understand
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Linearize the function around the point A. Then use it to calculate an approximate value of f(B), where B lies on
distance 0.17 l.e. from A in the direction (8, −15). (Please compare with f(B) calculated with a mini calculator).
Also state the equation for the tangent plane to the surface z = f(x, y) at point A.
@pastel tree Has your question been resolved?
@pastel tree Has your question been resolved?
@pastel tree Has your question been resolved?
............................................................................................

😭
Hehe I was away
back now 
Please tell me how you learned multi variable calculus:(
“With great difficulty” 
I’m currently dead in the water trying to find somewhere where I might learn what is necessary to be able to solve these hand in assignments that we are given
The course literature is so hard read
Not sure if it’s a me problem or the book
I can't even find the appropriate section where it covers Linearizing functions to be able to solve the questions
Most likely either they might have used different terms (my notes don’t call this linearisation) or that they’re just terrible, as before this is probably one of the harder topics overall 
Not even sure if I know of any good sources overall 
Anyways, yesterday we got to $f(6 + h, 5 + k) \approx 332 - 85h - 102k$, and figured that $h = \frac8{100}$ and $k = -\frac{15}{100}$
@tribal temple
Yes but, if i'm being honest with myself, i have no idea what we did?
This feels awful not being able to understand anything whatesoever
I'll never be able to pass the test at this rate
Awwww 
Are you at least happy accepting that we need to use this as the formula for now? 
Well, erm, basically it's like the "linear approximation" for multivariable functions I guess 
Like as per yesterday, similar to single variable functions, you can approximate a function near a point using the function value and the deriviative(s) there
Idk chartbit i'm kinda losing it mentally atm
It's been nearly three hours and i have literally zero clue or idea what i'm doing?
I don't have any sources to learn from
and i'm already like 2 weeks behind
hmmmm 
Alright say that you were given a function, and you knew nothing about it, other than you were given a point, and then you know the function output, and how the derivatives looked like
And you wanted to estimate the function output at some other point that's close to the point you were given
Do you have an idea of how you'd go about doing that? 

Like i know absolutely nothing
I have no source of learning material at all
No teacher, no book, no friends
So idk how i'm supposed to be able to solve this
at single variable calculus i could at the very least solve it by asking gpt or here
but it doesn't seem many study multivariable calc here
More that it's horrible to explain 
Anyways, you're happy that $\pdv{f}{x}$ tells you how the function $f$ changes in the $x$ direction, and similarly $\pdv{f}{y}$ tells you how $f$ changes in the $y$ direction? Or no?
@tribal temple
No i did not know that
i know that derivates shows the incline/decline of a given function
-that wasn't explained? 
Bruh 
Anyways that's kind of the idea of it, that's why you hold all the other variables constant when you're doing the partial derivative with respect to one variable
Because you want to see how the change in that one variable changes the output of your function
Ok
Cool, so are you at least happy with that for the time being? 
But like he has covered
all of this already and i have literally zero zero zeor clue on what they do
or how to use them
or the theory behind them
or what the signs means
Shouldn't i be able to solve the assignments that he gives us if i understand the formulas and the theory behind them?
For example for this question that we are doing right not it covers linearlization (this image^). Shouldn't i essentially be able to just utilize this formula to get the answer to the question?
Well yea and that's what we're doing 
Oh ;-; sorry :c
Us using that formula is how we got this here
ik i'm a pain but math really gets to me emotionally :( ||(tired of crying :))||
Wait are you happy at least with all we did yesterday, at least with how we found f(a,b) and the partial derivatives? 
(and you're not a pain
)
Welll what we did yesterday was that we were given a function and a point
and we utilized the middle part of this formula
But why is there a lot of other info on the formula?
what does the triangle mean? delta?
There are other equivalent forms to use this in, for now you can ignore this part (but it's talking about the directional derivative of f in the direction of v)
And yea, the change of f
"The change of $f$, which is $f(a + h, b + k) - f(a, b)$ is approximately $h f'_x(a, b) + k f'_y(a, b)$"
@tribal temple
oh oki
"For differential functions of two variables, the linearization equals the change in the tangent plane"
It this true?

What does this even mean xD
For functions of two variables, the linearization of it is the same as the change in the tangent plane
idk what a tangent plane is (i maybe know what linearization is, but not 100% sure.. )
You're happy in the single variable case with what a tangent line is right? 
Yes. A single variable case tangent line shows the incline/decline of a given function at a given point
Cool, and of course you notice that there's basically only one direction you consider in the single variable case
Right
But when it comes to two variables, then basically as you have effectively two dimensions in which you can move in, that at a certain point, you'd have more of a tangent plane, a two dimensional object, if you give me a second
something that looks like this, see how you have that plane that doesn't (locally at least) intersect the surface
right
Anyways, basically we have that this here effectively is the equation for the tangent plane at that point, you of course use the function value and the derivatives
Okay
makes sense
so instead of a tangentline we get a tangentplane
Why do we get new variables h and k?
Well, those are basically describing how much (in the x and y direction respectively) you change from (a, b)
It looks nothing like this
Well that one was more of a particular example rather than how exactly it would look, but (give me a moment
)
Then use it to calculate an approximate value of f(B), where B lies on
distance 0.17 l.e. from A in the direction (8, −15).
What approximate value do they mean?
Basically they're asking you to work out what f(B) is
But as per before, B is basically (6, 5) + (8, -15)/100
But how do you know that?
I'm given a Line from A to B
with a distance and a length
They tell you:
B lies on distance 0.17 l.e. from A in the direction (8, −15)
and (8, -15) has length 17
It's a direction vector for here 
well you can work it out manually
that sqrt{8^2 + (-15)^2} is 17
Makes sense
And as in its exact value, or what it's supposed to mean?
For the former, I'd need to work it out 
the latter, it's the value of f at the new point B, where as per before, there are those steps to work out what B actually is and all
Estimating the function?
aaaaaaaaaaaaaaaaaaaaaaaah i donj't understasnd HJAHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH
I don't even understand the question.
That's the whole linearisation thing we're doing now 
the problem is that i don't even understand the question
calculate an approximate value of f(B)
what is f(B)
we neither have a function
or B
f is the function in the question, and...
...B is that point as per before, a point that's "distance 0.17 [...] from A in the direction (8, −15)"
"Start at A, the point (6, 5), and then point in the direction (8, -15), but move a distance of 0.17"
Oh ok
but it doesn't specify that f is the funciton in the question?
That's what got me so confused
Okay so we are looking for the point B to be able to determine f(B)
Can we use the formula of a line?
Notice how the function is called f 
We start at A and end at B
that gives us a vector
and also a line L
and the variable t in the line L we set to 1/17
thus giving us the point B?
You could but as per before it's 1/100 you're moving, the line direction vector is length 17 after all and you wanna move a distance of 0.17, in other words, 1/100th of the direction vector
but
okay wait
So the directional vector becomes
B - A = (8,-15) - (6,5) = (2, -20)
And the Lines equation becomes :
L : (x,y,z) = (6,5) + t(2,-20)
The direction vector is (8, -15)
oh crap right
Ok so
L : (x,y,z) = (6,5) + t(8,-15)
and now we want the point B
They say it's 0.17 l.e
shouldn't t be 0.17?
That would only be the case if (8, -15) had length 1
if t = 1 then we get the point where the directional vector ends, right?
the tip
Can't i set t = 1, figure out the point. and then use t = 0.17?
Well sure, that would be how you've moved (8, -15) from (6, 5)
:)
then i have no idea
And as per before, you want to consider the length of the direction vector
t = 0.01 ?
Unless you want to change the direction vector, you could do that, you'd need to make it have length 1 if you really wanted to
That was way to hard lol
Awwww 
Merineth
and now i input it into the function?
Yep that's fairs 
And we want basically the h and the k, which is how much you've changed to get from (6, 5) to B, which of course is just h = 0.08, k = -0.15
For which, put those h and k into here 
Merineth
"Linearize the function around the point A. Then use it to calculate an approximate value of f(B)"
It isn't wrong, but it's not what they asked you to do
Well more that h is the change in x, the k is the change in y
hence this here
Because it's not the x and y values, h and k are the change in x and y: how does the x value change (for h)? How does the y value change (for k)?
Merineth
Notice how in the formula 
It's f(a + h, b + k) that they have in there?
So here, we had that B was the point (6.08, 4.85), but that is (6 + h, 5 + k)
In other words, 6.08 = 6 + h and 4.85 = 5 + k
That's why as per before you don't really need to find B exactly, you just needed to divide that (8, -15) by 100, as that gets you the h and k instantly for you 
Merineth
Yep, that's fine, you have that $f(B) - 332 \approx 8.5$
@tribal temple
Noting that f((6,5)) = 332
8.5 is the approximate change in the value of f between B and A
The 332 is the value of f(A)
oki
and lastly i want the equation for the plane?
iirc the planes equation was something like this
x+y+z = t
Yep, you want the plane equation, but that's quite simple-
i want the normal vector?
Well actually you've basically almost found the plane equation 
It's very hard to keep track of what i'm doing when i don't have an image in my head
but rather only numbers
(8,-15) isn't this the directional vector along the plane?
no?
meh
How am i supposed to visualize this
Right, see this here 
We have as per before that $a = 6, b = 5$, and we already found that $f(6,5) = 332$ and that $\nabla f(6, 5) = \pmqty{f'_x(6, 5) \ f'_y(6, 5) } = \pmqty{-85 \ -102}$
@tribal temple
Basically it's the thing you found before, but you replace h with x - a, k with y - b
just variables?
Yep, any x and y value you want to be 
Merineth
Yep 
Merineth
$z= 332+(-85)(x-6)+(-102)(y-5) \
z= 332 - 85x+510 -102y+510 \
85x+102y+z= 1352$
Merineth

Yep pretty much 
thank god i have you charbit
honestly idk what i would've done if i didn't have you???
(catropeemote)
Awww 
A certain cat here demanding treats 
But yea other than that, pretty much linearising a function and finding the tangent plane are the same thing 
pet him IMMEDIATELY!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
GOD what a cutie
i'll close for today ;-; i hope i see you tomorrow <3
tysm charbit :(
literally my saviour

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They’ve all gotten more than enough treats and attention, this one too 
See ya later
might be a bit busier tomorrow 
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can someone help me figure out what base case i use ? is it n = 0?
Yes
Yes, exactly
Ahh i see! Thank you 🙂
You're welcome
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wouldnt the two adjusted equations be same ?
no
one is saying
take f(x)
and turn it entirely negative
and the other is saying
take the x in f(x) and make that negative
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Shouldn't this be moved to MATH HELP?
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what do i do if i want to solve for theta
do u know what tan(x) means?
well before that
1
so u get it?
yes
okie
how do we know that tan is 45 degrees tho when its 1?
sinx/cosx = 1
sinx = cosx
now for what angle is that true?
sin(45) = √2/2
cos(45) = √2/2
do u know the unit circle?
there is one more solution
I dont have it memorized but yes
in the third quadrant
5π/4 = x
both sinx and cosx are -√2/2
so that must be a solution as well
ohh
so would the teacher expect us to know the trig circle by heart?
or is there a simpler way
well u only need to know the first quadrant
ur calculator will only give u one solution
its good to know one quadrant of the unit circle
since the radius is 1 on the unit circle, we get this:
and for sin(theta)=cos(theta), we want these 2 lines to be the same length
which is the case on the diagonal
ohh
so you get these two solutions
they also have the same length on the other diagonal ( f(x)=-x ), but then you have opposite sign
ohh
notice that usually, the sides would be sin(theta)/r and cos(theta)/r, i didn't write r because r=1
👍
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What do you know so far
I might know that I have to do the equation first and the answer I plug it into a graph?
Or am I wrong
Been a bit since I've done these types of problems though
first find the slope
if a line with slope -1/3 is perpendicular to another line, whats the slope of the other line?
that would be parallel
Now i solve for x right?
yes by plugging in (6, 8)
How would that look like quick question?
6 is x, 8 is y
8 = 3*6 + c
yep
sweet
so your final equation is
y = 3x - 10
Am I done with the equation? Or are there any other stuff I need to do?
thats it
Yay, thank you for your help!
@pale wyvern Has your question been resolved?
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If each x_i is strictly between 0 and 1 is this matrix invertible
@mint oriole Has your question been resolved?
should be yea
each column is linearly independent, since they're all almost (1 1 1 1) but point into different dimensions a bit
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here is my work progress for the following question
1a
and this is the correct answer
i’m not sure how they got this answer and what it means
They didn't ask you to differentiate it?
fredthebread69
i just found the derivative but im not completely sure what that means
What are you unsure about, your derivative or the solution of the question
both….
i thought my derivative was right but i dont know if i was even supposed to derive or what the answer means in general
where does that come form? is u just the inside?
So the expression
$1/(2x-1)^{2}$
like inside of parentheses?
fredthebread69
Can be written as?
(2x-1)^-2
$1/u^{2}$
fredthebread69
what is u? like what does it symbolize
or is it just a variable
and yes i agree
just curious if u has some sort of significance
ohh okay okay
Clear?
yes
Now you wish to differentiate it, so it's differentiation of u^(-2) with respect to dx
So we get $-2u^{-3} du/dx$
fredthebread69
Agreed?
yes
You seem to have done it right
ohhh so
the -2 is like
the outside basically
like the chain rule
that puts the -2 at front (i dont know how else tk explain it)
Pardon
and u is whatever’s inside?
like
how in the 2nd step
the -2
went to the front of the parentheses
is that where it’s coming from?
Say I differentiate
g²
All I know g is a function of x
I would get
$2g dg/dx$
fredthebread69
You differentiate your term normally then multiply dg/dx
Does that answer your question
@zealous tinsel Has your question been resolved?
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How can I justify the second one on the top
,rccw
Umm. Does someone know this
I keep trying random methods that don't work
They didn't taught how to do this
!!
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Sure
Sorry for being impatient
i think the question might be wrong as you cant divide a quadratic polynomial by a cubic
Oh , but it's in the NCERT example
I think they mean the other way round
i think thats the point maybe
Oh ok
q = 0 and r= ax^2 + bx + c

