#help-13
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is this right?
it is
alrr
by comparing f'(x)=0 first
you know how i hope
and write the sol. for x in terms of a
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@left bison Has your question been resolved?
srry its taking me a while
getting distracted
wait
this is what I did
I based it on an example shown to me
but I honestly dont get the relation with all that solving
I mean I get some
but
not entirely
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So i understand math but i dont see a clear connection with the negative ones like i do with the ones that are positive
And i do understand how for example * and / are each others opposite though
uh can you phrase your question more clearly?
what is it you need help understanding?
how are -, / and sqrt connected. It doesnt seem to be as simple as how 2+2+2 = 23, and 22*2=2 to the power of 3
So you understand how do +, * and powers work, but you need an explanation on how do -, / and roots work? You need the explanation of how do opposite operations work?
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I need help with calc 1 work
this is the problem ik the answer is supposed to be 1.5 but i having trouble trying to find that answer with the limit definition
and the f(x)=3/x with the lim = 0
if more is needed i can provide
<@&286206848099549185>
The limit definition is calculating the derivative, but the table is just the function
so would the answe be -3/4
shouldn't the derivative be close to the answer on the table which is 1.5
No the table is just finding 3/x
You can plug in 2 there just fine
Ur mixing up derivatives and discontinuities i think
But yeah -3/4 sounds right for the derivative i think, dont quote me on that though
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note that z* is the complex conjugate of z
and that z and w are complex numbers
I tried substituting but it I don’t work
whats the question?
solve for w and z
Could u show your work?
did you try w = a+bi z=c+di?
hmm, no
Is that 5 + 5i
you just get 4 linear equation from that
Yes
And 2i
for a,b,c,d
From 1st one you can get w*/z*= -2i and then sub in the second one
I get it now
i think both are fine
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hi
All of them or only some of them?
Well, those letters read a statement, and they‘re asking you to find a pair (x,y) such that the statement becomes false
Yes
And backwards E means "there exists"
Exactly
upside down A
backwards E
how
is it
this chapter
is it saying for all x belongs to an integer and there exists y belongs to an integer
Such that 2xy = 24
can i just be like 2(3)(2) does not equal 24
It‘s fairly easy to disprove when you think about it. First you can divide both sides by 2 for convenience, but then, it‘s saying: for all integers X, you can find an integer y such that xy = 12. that‘s obviously not true, otherwise 12 would have an infinite amount of factors
Yeah pretty much
no
choosing 3 for x
2 * 3 y = 24
there does indeed exist a integer value for y that results in 24
Oh I just read what they sent didn‘t compute. Oop
for your counterexample, you'd want to find a value of x where you can't get an integer value for y that works
if its not an integer or something
for all
maybe lets say
if x=24
y has to be 1/2
wait im confused again
yeh that works
because 1/2 isn't an integer
many many counterexamples
Because you just disproved the fact that for all integers X, there exists an integer Y such that xy = 12
why such that xy=12
2xy = 24 simplifies to xy = 12
for your counterexample, you'd want to find a value of x where you can't get an integer value for y that works
oh
i hate math
i rmb in this server i was asking how to prove similar triangles
and now im doing this
i hate life
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Bob's tiktoks viralize with 10% chance. Model by X~Ber(0.10).
Note that Y represents the total number of viral Tiktoks.
@ivory finch Has your question been resolved?
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@ivory finch Has your question been resolved?
what have you tried
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yo
can i have some help
this is the question:
and I arrived at parametric equations
and a plane equation
however I am confused about how to check if they intersect because one equation is in t while the other involves three separate coordinates satisfying (x-1)-(y-0)-(z-1)=0
so how does checking if one point satisfies the equation going to prove that it doesnt intersect if there is no such t
would I just check a point on the plane other than the one i used to make the equation?
because i'm just confused as thats a single point
of infinite on the plane
and unlike with two lines or something
you can probably make the first equation in x, y, z also
instead of t
but thats not how we were told to do circles
shoot
im sorry i can ask my prof i do appreciate the help
so take any t
that was acc mean asf
then the point will be (5cos(t)+2), 2, 5sin(t)+2)
assuming you've worked that out right
so then you plug that into the plane equation
yes
and see if it's ever true
but how many ts should i test?
you don't test any specific t
you have an equation in t
you can solve it
(5cos(t)+2), 2, 5sin(t)+2) could be any point on the circle, depending on t
so if any of these points satisfy the plane equation, there's an intersection
otherwise there's no intersection
so if (5cos(t) + 2 - 1) - (2) + (5sin(t) + 2 - 1) = 0 has any solutions, there's an intersection
otherwise there isn't
do you see how i got there
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can someoen walk me through how to solve this please
the way i would set it up is similar to the shell method
let's say f(x) looks like this
then we can slice the surface area into rings
rings with circumference 2 pi r, where r is f(x)
do you see what the area of such a small slice would be?
the function, yes
the 3d shape, yes but i dont know how, maybe i can find it out
ok i got it to graph in geogebra
but it's really laggy
now to get the surface area, we can slice it into these rings
this red ring has a radus of f(x)
and the area can be approximated as it's circumference times width
we are assuming it to be a hollow cylinder pretty much
which is ok because the width will be very small
this approximation becomes reality when the width get's arbitrarily small
as to how to graph it, i followed this tutorial: https://www.youtube.com/watch?v=dkF7edNwt3M
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Yo what did I do wrong here…?
look carefully at g(x)
I missed the square…
I always make silly mistakes like this… idk how and why
With these types of questions… is there a way for me to confirm/check my answr afterwards by plugging my answr back in or something like that?
not unless u use the computer
So you can’t plug things back in to check?
I like to double check my answers while writing tests
what do u wanna plug?
Like idk..
the same thing u manually calculated?
I want to double check my answr
Like you how with certain types of questions you can plug ur x val back in…. Can I do this here ?
there is nothing bad about having things wrong
what?
Nvm
And this is answr key
Does it matter that my x^2 and x are in opposite places
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Hi, anyone can explain me how to solve a matrix 3x3 using theorem of cramer?
i know when its a 2x2 you need to first calculate if you can do C-1, but if you can do it, how? (1 2 / 0 1) will be (1 1 / -2 -0) (i know 0 cant be - but only using it for the example) so how can i do that with a 2x2? Sorry for the hard explaining
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@elder abyss Has your question been resolved?
any1?
To solve a system of linear equations using Cramer's Theorem, you need to have a matrix equation of the form ( AX = B ), where ( A ) is the coefficient matrix, ( X ) is the column matrix of variables, and ( B ) is the column matrix of constants. Cramer's Theorem can only be applied if the coefficient matrix ( A ) is a square matrix (same number of rows and columns) and has a non-zero determinant.
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@elder abyss Has your question been resolved?
the next step is to calculate the Inverse, how do you calculate that in a 3x3.
Extend the matrix
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How would I even start this problem? We certainly did not talk about this in class 😂
Differentiate piecewise
Do I just use the power rule on basically all of them to get the answer?
so -2x-8 would be -2
but not sure what the domain has to do with any of them
They stay unchanged
so like what's the point of them being there when i've never seen them before?
just to kinda confuse us? 😂
just to make sure
-2
-4x
-4
0
are the answers?
No they're part of the function
No you're missing the domain of the function
so I have to write
-2 -5 <= x <= -2
-4x -2<x<=1
-4 1<x<=2
0 2<x<=5
neater than that in LaTeX, but that's the gist?
Yea
No
Format should look like the function
oh
Not individually
got it, so kinda copy what the original function is with v'(x)?
lemme write it up in LaTeX, hold up
Someone
@pseudo trellis I think the derivative is not defined at x = -2 and 2
could you explain that a bit further? sorry
@pseudo trellis Has your question been resolved?
wait, so which ones are wrong?
the domains should be -5<=x<-2 and 1<x<2 respectively
They are, no?
Someone
I'm confused :P
@pseudo trellis Has your question been resolved?
@pseudo trellis Has your question been resolved?
what the problem?
@pseudo trellis Has your question been resolved?
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Can anyone help me out with the shape of these contours?
I don’t really see how each of these contour give a different shape,
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I got |am|<=1 and |bn|<=1 but can't proceed after that
Lorentz
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who knows physics pls dm me
Help to calculate this integral
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How would I find the answer to this?
I tried finding the derivative of x and using critical points to see where the intervals were increasing, but that didnt seem to work
i mean f(x) not x
what's f(x)?
but you're asked to find where g is increasing
why are you looking at the derivative of something that isn't g?
so how do I find it
the same way you find where any other continuous function is increasing
take the derivative of g and see where it's >0
finding the derivative of g would be finding the derivative of the inside as well
and then finding critical points no?
no it would not
recall the fundamental theorem of calculus
use ftc-1 to find the derivative of g
thank you kanna but i'll be fine on my own
sin(x-pi/2)
ohh then i find critical points
i see
better
okay sorry 
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I understand why they've turned this into a piecewise function
but how come the bottom piece has -4 included?
So we have an absolute value in our function right?
yep
Well that's the one to determine the value of the function thats why we turn it into piece wise. So in one case the absolute value is positive and the other case its negative
The inside of the absolute value specifically
First case, x+4<0 so the absolute becomes -(x+4)
Second case, x+4≥0 so the absolute value is (x+4)
but why
do they include
I'm confused why the first one didn't include -4
and the second did
Oh its the same thing if the problem you got doesn't specify where to put the equal
If the problem you got doesn't say where to put the equal you can either decide to put it for x<-4 or for x>-4
But are you sure it doesn't specify
how are you allowed to do that
?
^
Thats what my teacher said well
Idk if you learn that any other way in uni
But usually my teacher said you put the equal for x greater
Wait, you want the function to be continuous?
I'm checking if it's continuous
also there's nothing wrong with
two holes existing
i.e 2 unincluded values
it's just you can't (apparently) have two included values
in a piecewise
It depends where it came from
Pretty sure
Your initial function is a /
So |x+4|≠0
Even if you simplify the excluded values should still be there
I didn't get this
or maybe one should and one shouldn't
so $x+4\neq0$
wyldinwilliam
$x\neq-4$
wyldinwilliam
there has to be an exclusion somewhere
which you achieved
but I'm curious why the flexibility
The function is also discontinuous at -4 btw
Wdym flexibility
yeah
Well it should be the same thing thats why
Graphing wise
The function will still be discontinuous.
It will still not be defined at x=-4
Graphing wise, same thing
You did graph your initial function
Im talking about the piecewise
You want to graph the piecewise, your problem is asking you thag
That*
I think the proper way then to do the piecewise would be to not include any values because you would be saying that at a certain point either the left side or right side touches the asymptote
so then how come the way this question is done they include -4?
Well I think a more proper way is to exclude -4 completely
If its not in the domain of the initial function
Then you should put it into the piecewise
yeah, that's why I was skeptical when I saw the inclusion of it
Since it comes from this initial function
So a better thing would be to completely exclude -4
From the piecewise
yup, going to ask my teacher about this
Due to the domain of the initial function
weird they'd include it
👍
Think im gonna ask mine too, bcz im a little confused as well haha
But thats probably it
You keep the domain of the initial function even if it simplifies
I think rhats it
that makes sense, but I do remember doing questions where
that isn't the case
so curious why it is here
Example?
uhh can't really pull one up but I've done piecewise examples where you actually do include the x value
just not with an absolute value like this one
where you actually had to come up with a piecewise
If the initial function is defined at the value then yes you include it
Its not defined in a value usually if you have /, √ or ln
(or in an Interval of values)
Like if you had f(x)=x|x-3|
Then the function would be defined everywhere
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Let $K$ be a field, $V$ a $K$-vector space and $\varphi: V \to V$ a linear mapping. Show that $\varphi(\varphi(v)) = \varphi(v) + v$ for all $v$ $\implies$ $\varphi$ bijective.
Is there anything I need to know about linear mappings to prove this?
I haven't read about them yet
This is similar to what we did before @crimson gulch
There is maybe one theorem that can help you
but i think you can do without
$\varphi$ is injective if $\operatorname{Kern}(\varphi) = {0_V}$. So here, we have $\varphi(v) = \varphi(\varphi(v)) - v$ and that is $0_V$ when $\varphi(\varphi(v)) = v$. That was my first idea
We need to show that that holds
Which one?
bijective iff injective iff surjective since it s going from V to V
which has the same dimension
so you only need to prove it is injective or surjective
So I can just show injective
yeah
if you prove one you are done
how do you know V is finite dimensional?
oh yeah we dont
Ok, then we have to show both ig
for showing injectivity, try starting with
phi(v) + v = phi(u) + u
then apply phi to both sides
use both linearity of phi and the given condition
How did you come up with that
just playing around with it, tbh
ThibaultF02
Yes
I think there's an even simpler solution. Write the equation as $\phi^2 = \phi + Id \iff \phi^2 - \phi - Id = 0$ -- then you can say something very specific about $\phi$, I think
spq_64_t
Or maybe not, hmm
@crimson gulch But I mean, that doesn't lead to phi(v) + v = phi(u) + u?
ThibaultF02
Oh
@sand cradle basic idea here is, show that phi is injective by showing that phi^2 is injective
$\varphi(\varphi(v)) + \varphi(v) = \varphi(\varphi(u)) + \varphi(u)$
$\varphi(v) + v + \varphi(v) = \varphi(u) + u + \varphi(u)$
$2\varphi(v) + v = 2\varphi(u) + u$
how did you get this first equation
More like this $\varphi(\varphi(v))= \varphi(\varphi(u))$
ThibaultF02
^
Applying phi to both sides of this
But he said
for showing injectivity, try starting with
phi(v) + v = phi(u) + u
then apply phi to both sides
That should be
No?
?
one second, let me actually write it down, i did it in my head earlier, might have screwed it up haha
ah it still works out but a bit more manipulation is needed
from there you get:
2phi(v) + v = 2phi(u) + u
as you said
then:
2(phi(v) + v) - v = 2(phi(u) + u) - u
rewrite phi(v) + v as phi(phi(v)) and similarly for the other one
i bet there's a simpler way, btw
once you get there it's actually done
since you made the assumption that phi(v)=phi(u)
for injectivity
so v=u
oh right, i'm overthinking it, i assumed phi(phi(v)) = phi(phi(u))
If we write it as $\varphi^2 - \varphi = Id$. Then for injectivity, for instance, assume $\varphi(v_1) = \varphi(v_2)$. Then on one hand, $\varphi^2(v_1) - \varphi(v_1) = v_1$, on the other hand, $\varphi^2(v_1) - \varphi(v_1) = v_2$. ||For surjectivity, $\varphi \circ (\varphi - Id) = Id$ should do the job||
spq_64_t
2phi(v) + v = 2phi(u) + u
if phi(v) = phi(u) then you can subtract 2phi(v) = 2phi(u) from both sides
Ok, it does render spoilers as latex, my fault
Oh
Is this way valid?
(and if we're in characteristic 2, then 2phi(v) = 2phi(u) are already zero 😁 )
phi(u) = phi(v), then apply phi and do what you said
sure, which step do you have a concern with
Applying phi
Alright, well then phi(u) = phi(v) => phi(v) + v = phi(u) + u (after applying phi) => v = u and we are done, right?
yea, just subtract phi(v) = phi(u) from both sides
Ok, then next, we need to show surjectivity
So all $v \in V$ can be written as $v = \varphi(z)$
For some z in V
yea, i'm still thinking about surjectivity haha
i think you would have to find an expression of z
Yeah
?
just rearrange phi(phi(v)) = phi(v) + v
as
phi(phi(v)) - phi(v) = v
use linearity on the LHS
phi(phi(v) - v) = v
yep
so if we call w = phi(v) - v
then phi maps w to v
v was arbitrary
so phi is surjective
Oh
How did you find this?
just noticed it for some reason
How, were you playing around with these on paper or just thinking about it?
i wrote down the original equation and was gonna start manipulating it when i just saw, wait, there's a v on its own, we can isolate it
and then use linearity
Ah, alright, thank you!
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I need help understanding a few of these problems
vvvvvvvvvvv
you can find BD using pythagoras
assume ab=x and ab=d and form two equations to solve
How does BD contribute to AC?
because you can make two equations with it
right triangles have well known ratios among all 3 sides
for two right angled triagles
they are sine, cosine, and tangent
Haven't learned trig yet
trig is not needed
you've learned a^2 + b^2 = c^2
Yeh
They're the same thing 😉
Ik
ok, so which are all the right-angled triangles?
The 3 rights are ABC/ADB/BDC
Bc is the hypotenuse of the mid triangle and the leg
form an equation for the other two right angled triangles
So would it be 9/AC = AC/7?
no form two equations for the triangles using pythagoras theorem
9²=7²+BD²
yes
how did you get this?
Large triangle
So after I solve ab I can get ac since it's js a normal theorem right
yes
Thank you imma try it
sure
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how to draw a trigonometry circle
You mean a unit circle?
yeah yeah that
I mean just google it. It will show all values. then if you have further quesitons I can answer them
Like what they represent
i tried but google is not googling
You googled "Unit circle"?
yeah
What didnt show up?
some vid bout teachers explining it
u see what i need is how to draw it with a ruler ad the stuff that draw circles that i dont know what its called in english
Oh like the tool to make a circle?
Called a "compass" in english
idk english is not my first language
Yeah I got that
You may also want a protractor to determine the angles
Not cause its bad its very good english
Yeah I was just thinking that haha
But you could also use a 90 degree angle like on a piece of cardboard or something and at least get a start with that
You can also take a glass or a cup and use that the create the circle
You don’t need a compass explicitly
thats th point i cant use a protractor nor a marked ruler
I mean does it have to be a perfect representation of the unit circle? Or can you just lable a circle with like roughly the correct lines?
it have to be corret
Well once you have a circle you can always draw a diameter as long as you mark the centre
Then form that you can bisect it easily enough
That gives you right angles
Connecting points A and B gives you another line that you can bisect
So that can give you the 45 degree angles
One thing I’m not entirely sure about is how to get the 30 degree angles
I’m sure there’s a way
yeah thats what im stuck with the 30 and 60 degree angles
"Learn how to construct a 30degree angle using just a compass and a straightedge in this step-by-step tutorial. Perfect for students studying advanced geometry and trigonometry, this video will show you the easy and accurate way to draw a 30degree angle. Watch now and take your math skills to the next level!"
-----------------------------------...
Bisect a radius (B to O, for example)
I’ll be real i don’t have a proof for why this works
The line from that bisected radius to a point perpendicular to your bisected radius gives you a 30/60/90 triangle
The reason this is the case is because cos 60 (your x value) is 1/2
mm.. not back to A, but back to a line parallel to B
Oh wait I just realized
The point at which the two circles intersect is exactly where you have a equilateral triangle
Since the radius is equal in all faces
And the angle measure of an equilateral triangle is 60
... what second circle? is this from the video?
So by creating a circle at A then a circle with the same radius at B, the point where they intersect is the third point of an equilateral triangle
i dont know what that is but it surly workedd
Then the arc is 60 degrees
Sorry the second circle isn’t made from B
It’s made in the line where the first circle has its edge
But that gives a triangle with equal sides
So the interior angle is 60
Then with a 60 degree angle it’s easy enough to bisect it
That’s cool
ah well strnger on discord thank u lotssss
took too long to sketch, but hopefully this better shows what I was trying to explain
cos 60 = .5
oh wait now i seeeeee
But that's why you get an equilateral...
.. because both of these are the radius of the circle
yeah yeah i get ittt
👍
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bruh im actually gonna ragequit
vectors are so aids
i never know which direction to go in
How the hell does this guy know how to draw the triangle
and that he needs to go QP
and not PQ
I thought it was PQ + RP
Never heard this one
for some reason i just drew a right angle triangle
i thought i could j straight up plot the points on a graph
and it would form the triangle
but no
You never know what direction to go in?
like idk how the guy got the triangle in the first place
(I,j,k) <-> (x,y,z)
how am i meant to know its meant to look like that
if i treat those letters
like x and y coordinates
they dont form a triangle at all
The number and direction of units in the cardinal directions
Cartesian coordinates
The direction is determined by the sign of the coefficients, - or +
Oh
Because you are supposed to draw both vectors from the same point
The starting point is (0,0)
However, the orientation and placement of the grid (not shown) is completely arbitrary for simple notes drawings like this
does that mean
i cant plot
the points on a graph
It does not mean that
cause im p sure thats what i did
The first point should Go right 3, up 5
and i have PQ as (3,5) and PR as (13,-15)
yeah
but theres no way to connect these such that they form a triangle
Weird drawing
ohhh wait
ig its not a straight line up
?
yeah
ok
idek bruh
idk what other explenation it can be
cause thats looking like a rectangle otherwise
i think thats it
thanks
or i may be wrong
yeahhhhh
p sure i got it now
god i hate this shit
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To go from Q to R by following the existing vectors, you have to trace PQ backwards and proceed along PR
That is in fact
QR = QP + PR = -PQ + PR
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How come a cotangent function's graph starts from zero and is not centred around zero such as tangent?
Are you asking why there’s an asymptote at $x=0$?
Civil Service Pigeon
well yes, because with tangent if the period is pi over 3 then the 2 endpoints are $(-\frac{\pi}{6}), (\frac{\pi}{6})$
Tomi
yes
$\cot 0=\frac{1}{\tan 0}$
Civil Service Pigeon
What do you notice? (hint: ||what is tan 0||?)
well $\tan 0 = 0$
Tomi
and what happens when you divide by 0?
its quite undefined.
And so you have an asymptote at that point
but what is the difference between this and tangent? how come tangent has a real number at the centre?
Because $\tan 0=0$ and $\cot 0$ is undefined
Civil Service Pigeon
ah yes because it is $\frac{0}{1} = 0$
Tomi
In terms of this, how would I graph it? Would I just add pi over 4 to my x axis so I would start there?
or would I change the period?
what would the period be?
simply 1 pi?
Yup 
so an optimal interval would be $(\frac{-5\pi}{4})(\frac{3\pi}{4})$ being $\frac{-\pi}{4}$ at the middle.
Tomi
If you mean to show two cycles of the graph then sure
hmm, isnt this a right shift?
makes sense
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I have 2 questions
where did 1/2 come from and why is it t^2
this is a defined integral, doesn't that mean that we don't just work it out (if we did then it would be t^(2)/2) but substitute whatever is in the integral with our defined borders?
they integrated t dt
and they are substituting in the bounds of hte integral
see the vertical line
T on top 0 on bottom
@gaunt nebula
oh so we do normally integrate it first
thank you
ok second question now
sinusoidal signal
that is how you do a definite integral
integrate, and then substitute the bounds
$\int_{a}^{b} f(x)dx=F(b)-F(a)$
Austin
yeah i guess i forgot
exams nuked my brain
anyways
why do we add omega in a sinusoidal signal?
I need more context to understand what you're asking about, but likely omega just represents the frequency of the sine wave
for example
,w plot y=sin(x), y=sin(5x)
if omega =1 or omega=5 the frequency changes
here
electricity
why did we add omega in the middle of the function then?
why not just in the beggining?
also is this only for a sinusoidal signal or?
there's not enough context I don't know what your asking
beginning of what
calculating the mean of the signal
I think its RMS but im not sure
of the integral
we just seemingly randomly add it in step 2
how would you want to add the omega at the start
it’s not random, it represents the frequency of the signal
I don't see how the equation would change by just making omega appear earlier
here
that makes no sense
we don't change the bounds of integration before making our substitution
what are you trying to do with the omega there
wait why we do substitute T with omega * T
it’s a u-sub
Well they add it later on and it seems like the equation wouldn't change if we just add it in the beggining and its also less confusing
it does change it
they don't just "add it"
i would suggest you go watch a video on definite integration, especially on definite integration using u-sub
it would clear up where the omega came from
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Here, it says the formula for trapezoid is 1/2 (a + b)h but my teacher says the formula for trapezoid is base 1 + base 2 x height then divide by 2
Why one correct
you said the same thing twice
Huh
$\frac12(a+b)h = \frac{(a+b)h}2$
i don't understand either, what's different
hayley!
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you solution is pretty poorly written. it's like you took cases where f(x) = x^2 and f(x) = -x^2 and showed the integral converges in both those cases
while i agree what you're ta wrote isn't what you tried to do, you're solution still isn't great
yea ok ig that's true...
other than the 'must' part
doesn't matter, just that's not the only option you have
yea i can't really argue with that lol
it is sufficient to do that, yes
it wasn't clear to me what you were doing before this discussion tho
Did you write anything after the statement both sides are convergent?
nvm i didn't read correctly
i don't get the ta
because it's clear to me that you're not trying to use squeeze theorem
are there some negative signs/inequality issues here?
forgot a minus sign
you wanted to bound it above and below right
no i think you misunderstand what i'm saying
i think what might've been more clear is if for the first case instead of that you wrote $-\int_{1}^{\infty}e^{-x} dx \leq -\int_{1}^{\infty} \frac{1}{\sqrt{1 + e^{2x}}} dx$
$\int_1^\infty \ldots dx \geq -\int_1^\infty e^{-x}dx$ is what you get
didn't wanna type all that out
in trying to prove it converges yes
as -infinity < that integral
:D
i think because they are both the same the ta thought it was supposed to be squeeze theorem
but idk
because to me there is no implication or statement that squeeze theorem is gonna be used
btw the graph of the function 1/sqrt(1+e^2x) is pretty
i don't see how the given solution is all that messy
4C
there actually is something interesting
the first two terms cancel
the integral from -1 to infinity of that function is $\sinh^{-1}(e)$
4C
nice
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I wanna know how to do c
Did I screw up on c
Please don't occupy multiple help channels.
What is t-formulae?
@fair nymph Has your question been resolved?
@fair nymph
yea, it looks familiar right?
Wdym
Yh i did that
I wrote that it = tan theta
Your confusion is about tan 11pi/6?
How
you can find any angle thats a multiple of pi/6 or pi/4 (without half-angle)
Oh
(or you should know)
What a pity 🥲
Wait but tan 330 ain't right
and 330° = 360°-30°
It is
But the question requires you to simplify it
Can you explain 😭
I guess you’ll learn them after a few courses in class…
Isn't that pi radians