#help-26
1 messages Β· Page 160 of 1
Isn't this the definition?
yeah, but I want to prove that |1/x| = 1/|x|
How does it even follow from this?
If you have the lemma |ab|=|a|.|b| then put a = 1/x and b=x
I mean that was the previous question
cool, then apply it
okay, so |1 \cdot 1/x| = |1| |1/x|
technichally, what is this study? its kinda intresting on how you have a massive open field but here you decided to go to the forest, shoot yourself in the leg, blind yourself and see how it goes
yeah, which is just saying |1/x| = |1/x|
this sub will be better
LOL
Let me ponder over this a bit more
hmm
I wonder what would you call using only FOL axioms and ZFC then
chopping off your limbs.
(mods dont ban me π)
this would give |1/|x|| = |1/|x||
this sub is the best you can do probably
it should follow from this
$$ |x| =
\begin{cases}
x & \text{if } x \geq 0,
-x & \text{if } x < 0.
\end{cases} $$
Latias
Compile Error! Click the
reaction for more information.
(You may edit your message to recompile.)
woops
or you could go completely without that lemma, and do it by cases
but yeah it should follow from the piecewise definetion of absolute value
unless you want a completley useless result
why
subsitute 1/x for x
|ab| = |a| * |b|
|1 * a| = |a| * 1
|a| = |a|
this is what happens when you plug in b = 1
try a = x and b = 1/x
or just do it without this lemma and prove it for x > 0 and x < 0 seperately
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pro
are there any angles which are the same?
i dont think so
you can use that AB and DC are parallel
You mean at D and at A?
oh whoops you mean at D and at B
You're right
since its alternate
omg im smart
tys,
tysm
so for that i can use sine rule to get th value of angle 0?
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So I got 3 points
I'm assuming that vertex is (0,0)
(-200, 100) left tower
(200, 100) right tower
where is the road?
oh the surface of the bridge
nvm
Can you clarify what is meant by the 'road'?
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Calculating my reactionspeed and am not sure if this is correct, i used desmos to calculate but the reactionspeed of 0.019 seconds doesnt seem reasonable: t= speed in seconds) t = β2 Γ 0,136/9,82 β 0.019 is this correct or did i mess up? any help very appreciated since i need this for a paper im writing for school, ty in advance π
where are those values coming from?
!original
Please show the original problem, exactly as it was stated to you, with the entire original context. A picture or screenshot is best. If the original problem is not in English, then post it anyway! The additional context might still be helpful. Do your best to provide a translation.
gimme 1 sec js gna type it all out
ok
started with s=Β½gtΒ² (weightaccelleration equation) s is time, g is weightacceleration on the surface of the earth and t is time
then solve for time
t= β2s/g
then i inserted the object falling length 13.6 cm = 0.136m
you neglected order of operations when entering the value into the system
to be clear, you should have
$$t = \sqrt{\frac{2s}{g}}$$
$$t = \sqrt{\frac{2\cdot 0.136}{9.82}}$$
βΞ±ΞΌOmeganato5
also why 9.82 instead of 9.81 for gravity
noway i got gravity wrong xd
it was in my textbook i think
okay i got it to 0.166 seconds that makes more sense ty omega β€οΈ
$$t = \sqrt{\frac{2\cdot 0.136}{9.81}}$$
πππππ4ππππ
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how can i isolate lambda here
π¦
you can isolate but then youll get it in terms of dy/dlambda
again y is a new variable so nope
k ty then
yea
oh that was your process
its part of a lagrangian function
im trying to solve lambda in terms of b
then find optima
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I need help with something sadly
Is there a way to write this easier?
I've tried to cancel the cos(30) and sin(45) out, but it appears I was wrong
Ohhh wait I forgot sin(45) also multiplies with sin(30)
Yeah, but writing that in a calculator during an exam isn't so good
tfu need a calculator
is a + sign
alternately, divide by sin(30) in the numerator and denominator and move the cos over to get cot double angle iirc
thats unspottable
cot angle sum*
I can't type cot in calculator
oh it doesnt even matter because thats cot75
id jst brute force it, those are nice enough values
Well rip my time in exam, ty then
gotta remember your first quadrant unit circle values
I have tried to cancel things out, but I get different results
Actually I might have been just dumb
Oh yeah I was
cos(30)/3+cos(30) is not 1/3+1
It's fine then thank you I just made a no brainer
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Is this a valid proof?
I meant "linearly independent" on the third last line
I don't know what plus/minus theorem is, but I guess it is just computation. Yes, this argument will work, and you can also argue that this algorithm will eventually halt as the vector space is finite dimensional.
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!status
What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
1
@mortal marten Has your question been resolved?
Thanks for repeating the question idk how to read
Are you gonna help or what
Exactly
hows BC = BE + EC
Oh
Yeah i see
Hold on let me write allat
Ok ok
yeah
Ok ok im writing hold on a sec
could you explain this
Afe isnt a triangle tho?
AFE isnt a triangle is it?
Did you make it a triangle
ohhhh
Yeah
so all ratios are equal?
alright i will try to solve now but i wont close channel incase i dont figure it out
The angle-angle of AFE and ADC are <EAF=<CAD and what else?
The angles F and D? how are they equal
Ah ok
Hey i still cant get to the solution
wait can you explain this too?
@mortal marten Has your question been resolved?
<@&286206848099549185> can yall help? read the previous messages
!status
What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
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5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
2
@mortal marten Has your question been resolved?
@mortal marten Has your question been resolved?
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am i doing anything wrong? itβs giving different answers than expected but i canβt find the mistake
what's the expected answer
I don't see an error with the diff so far
i donβt know, i just plotted the function in desmos and when i graphed βfβ(x)β the function looked different than when i plotted the derivative i computed
not that i took a low upper limit for the sum, i tried n=500
screenshot your graphs
hm check the symbols and send the desmos plot
gonna take a bit bc i closed the app
could be that desmos doesn't handle gamma,digamma,inf sums that well, I haven't used it for that, but maybe it's reliable enough
i canβt find how to share desmos graphs on mobile
That looks the same to me
The difference between the two is likely a difference in the convergence speed of the summations
look around x=0
okay
but at a limit that high it shouldnt be almost a quarter unit right?
It could very well be the case, and I would assume it is unless you can put rigorous bounds on the error
also, this sum came up when calculating $\int_{0}^{\infty}\tfrac{\ln(x)}{\cosh(x)}dx$, but when i calculated fβ(0) (the value of the integral) it was almost the same (like 5 decimals or smth)
pixel
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no idea where to start from please help
@tender abyss Has your question been resolved?
ew
okay so first of all, what relation do f(x) and g(x) roughly have
sure
let's try to make those a little more precise
first of all
pick any point of f(x) to try and "match up" with the bottom graph
say..
misaw mb
let's try this part since it looks a little easier to deal with
first of all
it's very clearly the same part as g(x)'s leftmost
segment
so the comporesions is 1/2
i think it's closer to 4/7 but im going to want like
a little less than a lowball
wait
i miscounted
it's more like.. 2/3rds
actually wtf am i cooking
π
let me count one more time lmfao
yeah it's 1/2 okay
ignore that
i can count
trust
so right now we have 1/2f(-x)
mhm
-2?
lot more than -2 it looks like
lets pick f(2) to test this on
aside from the vertical shift
we've got
if tis 4 it reflects to -4 and -2 is -6
he might be cooking
but on the key it syas -17/2
oh yeah so
lets use the horizontal line instead
mk
so
we've got the red line on the left as
1/2f(-2)
which is pretty close to g(x), but we just need to shift it
its y value is 2.5, g(x) is -6
so we get -8.5, or (guess what)
-17/2
!!!
wdym y value?
okay so
you take the y value of f(x) at.. sayyy
2
which is 5
right
mhm
that's the y value for f(-2)
now we just divide that by two for 1/2f(-2), which was the equation we came up with
mk
the y coordinate of that point is -2.5
whar
no it's okay
2.5
waiting
7.5
still nope
that's 1.5
8.5
Serphic
np!
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hi i have no clue where to start with this questions
The following error occured while calculating:
Error: Invalid left hand side of assignment operator = (char 6)
what does that mean ^ π§ββοΈ
just think about playing one round first (so each person rolls once)
what's the probability A gets eliminated? what about A doesn't get eliminated but B does?
so like Pr(A is elim)*Pr(b and c don't get elim) ???
hm just pretend the "round" ends if one gets eliminated
sorry huh π§ββοΈ
π§π»ββοΈ
ok like
there are 3 different ways we can go down to 2 players
A,B left, A,C left, or B,C left
well nvm that
we can just think of it like
we play a round where every player rolls once and the game ends immediately if one player gets a 6 during the round
but if no one rolls a 6 we're just gonna do the same thing again
so we can just think about one round first
there is this equation that they gave us but i have never seen this in my life HELPAHSD
wait lemme show

in round 1 would the probaility of each one of them getting elim be just 1/6 or have i got this completely wrong
not quite
for A it is 1/6
for B to be eliminated, we'd need A to not roll a 6, then B to roll a 6
so 5/6 * 1/6?
yea
and then c 5/6 * 5/6 * 1/6 ?
yea
and now i have no clue where to go from here man :D
how tf
in one round
how did u get those π
5/6 * 5/6 * 1/6 = 25/206
1/6 = 6^2/6^3 = 36/206
i just gave them all the same denominator
yeah i would say i'm alright with it
ok
we can just assume we're on the round someone gets eliminated
the ones before it (if any) where nobody gets eliminated don't matter
so then you can compute the probability A gets eliminated given that someone is eliminated (i.e., at least one person rolls a 6)
and same for B, and C
wait sorry let me try take in everything u said and try the question again π thank u !!
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Help
Does the answer matter? Like if you handed it wrong, whatβs the consequence
Bad grade..
hiiiiiiii
You should check it yourself, grade doesnβt really matter tho. The grade will come after should you put the efforts in
this is supremely unhelpful. if you don't have anything constructive to say it would be better to just not say anything.
I apologize
thank you for reading my modmail
sorry if my ton of messages (separated) were distracting
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How do I do this. Just number five
polynomial with degree n should have n not necessary distinct solutions
but complex solution is special because if one is the solution, its conjugate is also the solution
Because you can always create a polynomial with degree n using multiplication
$P(x) = a(x-r_1)(x-r_2)\dots (x-r_n)$
for constant $a$ and solutions $r_1,\dots r_n$. Notice that this multiplication results in $ax^n + \dots$ polynomial
annoying
Yes
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How to do 9
,rotate
which question
Draw a triangle with hypotenuse 7 and one side 3. Find the angles corresponding do your inverse sine/cosine values
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i am confused as to how this is wrong. this is my calc 3 class and i really dont understand
show us ur work
,rccw
shouldn't it be -55?
(while they accepted it, probably better to use the (1, -8) one tbf)
oh my gosh i was losing my mind and it was a negative sign thank you lol
Seeing in the first part you find the slopes, call them m, from there you can write the parallel vectors as (1, m)
okk
thank u guys!
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How do you find angle Theta? I don't understand how to even after watching multiple videos. I feel like I'm missing something.
First of all, you have cosine squared, to find angle you have to solve this equation for cos first
Any ideas how to do it?
Not really
I have the answer, just need to know how to get it.
i would start by square rooting both sides
cos(theta) = t
Yeah I was trying to say this but without saying this
π₯Έ
why not just say it
Here is the answer I'm trying to understand how to get.
did you square root both sides dottoe?
Bc there is no point on giving him solution if he will not understand, I wanted him to solve this, not me
Idk
Maybe I'm wrong
I watch videos about it, but it keeps talking about other equations I don't know about.
how about you try square rooting both sides
I'm trying to.
I was mainly just asking if there was a equation wheel that I needed to know about.
ok, ty.
Its the inverse function of cosine
Also make sure you can get all 4 answers
I was just having trouble with figuring out how to solve for 0 in cos(0).
If you need a hint for why there are 4 answers you can ask, otherwise I think you can figure it out on your own
I may need a hint, that is the main part that confused me. I know it has something to do with quadrants.
what happens when you square root both sides
1/4 becomes 1/2, having only Cos(0) = 1/2
are you sure thats the only possible square root?
also -1/2
how many solutions does cos(theta)=1/2 have? (in the interval [0,2pi))
2
what about cos(theta)=-1/2?
2
how many solutions in total?
two more because cos(2pi-x)=cos(x)
Ah, it was radians/accros that I was having trouble with.
From 1/2 to pi/3 is because of arccos, and then the other angle that works for that is 2pi-pi/3, which is 5pi/3, due to cos(2pi-x)=cos(x)
You can do the same process for -1/2
Oh yeah, I remember now, the unit circle.
Ok, I remember now, thank you very much.
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Bark vark
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Incoming question re: Peano addition. I'm just now learning it, and am getting hung up on one of the steps in a simple introductory problem.
S(S(S(S(S(0)) + 0)))
So you dont know how to proceed from here?
S(S(S(S(S(0)) + 0)))
S(S(0)) + 0 = S(S(0))
S(S(S(S(S(0)) + 0))) = S(S(S(S(S(0)))))
No, the step prior to that. I don't understand how you get from S(S(S(S(0))+S(0))) to S(S(S(S(S(0)+0)))). I keep ending up with something different.
S(S(S(S(0))+S(0))) = S(S(S(S(0) + S(0)))) = S(S(S(S(0 + S(0))))) = S(S(S(S(S(0)))))
@cerulean star this should work I think
it's just moving the S(0) inside
Okay, I'll check it out. Lecture starting here in a minute, so I'll close the channel and come back to the server after I've tried the problem again. Thanks!
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can tan^2(theta) = sin^2(theta)/cos^2(theta)?
Please don't occupy multiple help channels.
ok
yes
type .close
can? It is equal to that
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How would i differentiate this with respect to x without a calculator on tech free
The textbook got
But this didn't show me any working out so i was unsure how it did that like how is it 24(3x+4)^3 should it not be 8(3x+4)^3
They used chainrule
U do normal power rule
But multiply buy the derivative of the inside
The derivative of 3x+4 is just 3
So multiply by 3
You would use chain rule when you have a function within a function
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Im doing number 6
Could anyone check that I'm correct
Im not confident in my answer
<@&286206848099549185>
I donβt think that is what is being asked
Oh wait whats the q asking for then
What do you mean how to write it?
No
So I have it right?
No
What am I doing wrong?
No, f(x) is jst the notation for a function meaning that whatever u input into x, it will give u an output so e.g f(x)=x+1 thats simply saying whatever is input into x, add one and thats the output, think of functions as a machine that does a certain process to whatever value you input into it, to give you an output
Oh ok
So I don't include the f
I just have -2x-3
Because that is what is outputted
Wait
Yh
Recheck your numbers
Answer is (-4x-15)/2
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As for the values that this function can take
is geogebra messing with me?
Is it not ]0, 1]??
Or does it not care about the fact that we have a negative square root since arctan squares it? ._.
Yeah No seems lite itβs the opposite of What i thought lmao
xβ 0
Yeah hence the ]0
But isnβt the restriction on the f(x) based on the g(x)?π
interesting, we use ]
[0 if included ]0 if not
Yes but square root only for positive?
ahh true
And unless iβm too dumb to me it seems like itβs when 0<x<=1
because it is
so What should the domain for the entire function be then?
,w graph arctan((1-x)/x)
oh so then i was right?
yes
you probably typed it in wrong
Ok ok Wait since you know How that stuff work
Whatβs the derivative
-1/(x*2sqrt((1-x)/x)))?
pleaselordletthisbethecase
derivative of arctan(u) is $\frac{du}{1+u^2}$
knief
differentiating the sqrt function to find du
gives
well first iβll rewrite the inside of it because i donβt feel like doing quotient rule
youβll get (1/x)-1
hmm
knief
Compile Error! Click the
reaction for more information.
(You may edit your message to recompile.)
hmm
iβm new to latex iβll just type it
you know how to differentiate though right
,w differentiate (sqrt((1-x)/x))
oh no
this is your final answer
-1/(x*2sqrt((1-x)/x)))?
Does look so
fuck ye
Okok and then
Ln(tan^2(x)
is that 2/sinxcosx?
cot^2(x)(2tan(x))(sec^2(x))= 2tan(x)csc^2(x)
ruhroh
which is 2/sinxcosx
i have to go
Haha Aight
i have class
Thanks mage
youβre welcome
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Find the area of the shape bounded by the curve ( y = e^{-x} \sin x ) (for ( x \geq 0 ) ) and the x-axis.
miyo
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haha it's ok
you can just delete it
@strong sable Has your question been resolved?
you have learned integrals already right?
if it's asking for the area bounded by a curve and the x-axis, it's just the integral of that curve
since it's asking x>=0, we need to have limits from x=0 to infinity
yes This is what i've done: β« e^(-x) sin(x) dx = -e^(-x) (sin(x) + cos(x))
could you explain what you've done here?
integration by parts
yes, that's the right move, but why do you have another integral on the right side?
after integrating by parts you should have: something -integral(something)
how is last step correct
oh yeah i overlooked that
you forgot the integral part of second time integrating by parts
$\int e^{-x} \cos x , dx = -e^{-x} \cos x - \int (-e^{-x})(-\sin x) , dx = -e^{-x} \cos x - \int e^{-x} \sin x , dx.$
miyo
yes, very good, now sub that in here
i don't think this is right
he went backwards
first he integrated cos and differentiated the exp
now he differentiated the cos and integrated the exp
oh yeah because then we just get zero
after substitution he will get back $\int e^{-x}\sin(x)dx = \int e^{-x}\sin(x)dx$
yes exactly
Mohamed Mohsen
so we need to take u=e^-x and dv=cosx the second time integrating by parts
My no brain moment
lemme re calculate
[ \int e^{-x} \sin x , dx = -e^{-x} \sin x - \int -e^{-x} \cos x , dx ]
[ \int e^{-x} \sin x , dx = -e^{-x} \sin x + \int e^{-x} \cos x , dx ]
Where [\int e^{-x} \cos x , dx = -e^{-x} \cos x - \int e^{-x} \sin x , dx ]
[ \int e^{-x} \sin x , dx = -\frac{e^{-x} (\sin x + \cos x)}{2} + C ]
[A = \int_{0}^{\infty} e^{-x} \sin x , dx ]
yes, thats correct
fr this time i know earlier i said it was correct but wasn't
so now just plug in the limits of integration
miyo
[\lim_{x \to \infty} -\frac{e^{-x} (\sin x + \cos x)}{2} = 0 ]
When x approaches 0 [-\frac{e^{0} (\sin 0 + \cos 0)}{2} = -\frac{1 \cdot 1}{2} = -\frac{1}{2} ]
miyo
,w \int_0^{\infty}\sin(x)e^{-x}dx
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can someone help me see why the flux across this rectangle (assuming delta x and delta y are very small) equals
$\qty(\pdv{M}{x} + \pdv{N}{y}) \Delta x \Delta y$
eugene_krabs_has_cake
do you know the definition of flux?
$\oint_C \mathbf{F} \cdot \mathbf{n} \dd{s}$ right?
eugene_krabs_has_cake
that's not the definition, that's a line integral. it's also one side of green's theorem
well in 2D i know it quantifies the amount to which the vector field flows out of the curve, so it sums up the component of F in the direction of the normal to the curve
but i think in this case i need to split up the closed line integral into 4 line integrals and calculate that, but im not really sure how to
even though i know the normal in each of those cases
sorry i was a little wrong. i was thinking flux in terms of a surface
depends on your book's definition, so you should just look that up and start there
yeah im just caring about the flux across a line integral, instead of across a surface, i think this is for deriving the divergence in 2D
this is the only real "definition" of flux that i have
,av eugene_krabs_has_cake
the Flux part at the bottom may help
https://math.libretexts.org/Bookshelves/Calculus/Supplemental_Modules_(Calculus)/Vector_Calculus/4%3A_Integration_in_Vector_Fields/4.6%3A_Vector_Fields_and_Line_Integrals%3A_Work%2C_Circulation%2C_and_Flux
i may be being stupid but i dont understand this last line
y(t) is just 1
for this im not too sure how to make this general with M(x,y) and N(x,y)
replace x with M(x,y) and y with N(x,y)
but if we go from the top line, would r(t) be (x + (delta x) * t, y + delta y)?
or smth close
but when you evaluate the integral wont you have something like M(x(t),y(t)) and N(x(t),y(t)) which you dont know how to evaluate?
yea. just do some problems and see
In this section we will introduce the concept of an oriented surface and look at the second kind of surface integral weβll be looking at : surface integrals of vector fields.
but im not doing the flux of surfaces, just lines for now
if i label c1 as the bottom side, would there be any truth in this equation?
i feel like its wrong since M and N are functions of x and y which would be functions of t aswell so it wouldnt just be a constant in the integral
this is the exact thing im trying to figure out
i just want a bit of help into the explanation of it, preferably the top 2 lines, since the left and right will probably follow easily from that
which part of the top two lines don't you follow?
F = M ihat + N jhat
So F dot j = N
just how they really derived that the flux across the top was .....
yeah
do you know what n is here?
in the case of the top its j
yes
i understand the equality after this
just not that bit itself
so we have the n being j
it's just approximating the integrand as constant
so im trying to compare it to $\int_{C_1} F \cdot n \dd{s}$
eugene_krabs_has_cake
since delta y and delta x are small
so are you saying that they are basically just doing $$\int_{C_1} \mathbf{F} \cdot \mathbf{\hat{n}} \dd{s} \approx \mathbf{F} \cdot \mathbf{\hat{n}} \cdot |C_1|$$
?
eugene_krabs_has_cake
@frail reef Has your question been resolved?
yes
so im assuming $\int_{C_1} \dd{s} = |C_1|$ is something thats always true, but i dont understand why we can treat the integrand as a constant since the components of F are functions of x and y
eugene_krabs_has_cake
you're just linearizing
F(x, y + dy) is approx constant if dy is small enough
do you know what linearizing is?
is it $F(x, y +\Delta y) \approx F(x, y) + \pdv{F(x,y)}{y} \cdot \Delta y$?
eugene_krabs_has_cake
actually simpler, just the first term
only because delta y goes to 0 right?
or is it just a crude approximation
ok so are we saying that F(x,y) is constant with respect to whatever variable we are integrating?
yea the assumption is delta y here is small enough for you to ignore
i just dont see why we can say F(x,y) is constant, my brain might be fried tbh, this seems like its easy
but arent we saying F(x,y+delta y) is constant because it can be approximated by F(x,y) and F(x,y) is constant?
is delta x and delta y some kind of variables and x and y are constants here?
Ok so am I thinking about it in a correct way if I say that the only thing that varies in the flux integral is F, and over that line, y stays the same, x goes between a coordinate x and x + delta x
And when we evaluate F on that line we get F(something, y) where that something goes between x and delta x, but wherever that x is evaluated at, between x and delta x, the function is basically the same as F(x,y)
(This is for the bottom line)
@frail reef Has your question been resolved?
@frail reef Has your question been resolved?
Crazy username
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Hello! I was hoping to get some help with a Domain/Range problem in my College Algebra (1148) class. There are two straight lines that are perfectly horizontal on the graph. I was assuming it would be R[6]U[8] but wanted to verify if thats the right answer and if not what else it would be?
@glacial nexus Has your question been resolved?
@glacial nexus Has your question been resolved?
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hallo
@sage jetty Has your question been resolved?
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Lim x approaches to 0 sinx/x is equal to something else
It's a pretty well known limit
Sure
I actually stop solving it once justtopro started taking over it
Heβs a better man than me
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i get how the first 3 are true but how is the last one converse of corresponding angles
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i js need someone to check my answers
13. x= -5 14. x = 8 15. x = 3 16. x=7
and this is x = 9?
TYSM
sorry for disturbing but please remember to close the channel to make it available to others
a is equal to f because of alternate angles
alternate angles are angles that are in between lines that complete a "Z"
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a?
its asking abt f
c and f are alt interior
but what other proofs or steps do i put to get to that
that i know of
yo what you need help with
ah i see you started proofs
b and c verticle angles and c and f are alternate interior
but also write what is given as the first statment
HI AGAIN
okay i js gave up on that problem β οΈ but thanks
@ornate beacon Has your question been resolved?
since AC β BC, AD = DB, and both triangles share CD, you can prove congruency through SSS.
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is an undefined slope an inflexion point?
no, an inflection point is a point where the second derivative changes signs
okay thank you
wait but like it becomes undefined so that doesnt work?
if after the undefined slope it changes sign then does it count?
well if the first derivative doesn't exist then the second derivative doesn't either. so it is potentially a place where the second derivative changes
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How to make an equation of this?
what do you think
I tried to put some numbers but I couldnβt figure out
so one investment pays 18% meaning youll get an additional 18% of the amount of money you put in that account and same logic for the other account but 12%
let x = the amount invested into the 18% account
let y = the amount invested into the 12% account
what can we say about the amount we have a year later
if it pays 18%
mathematically what does that mean
The amount is going to increase
right so we can say x', the amount of money in the 18% account in a year will be 1.18x
right because its x, the initiall amount plus the 18% of the initial amount it pays in a year
so x + 0.18x = 1.18x
Then what do I do with 12%?
y+0.12y=1.12y
Then how do I solve each investments
Like how do I solve just by these two equations
Is it equal to 27480?
0.18x+0.12y=24000?
no
x and y are the initial investments
and they sum to 24000
so x + y = 24,000
and 1.18x + 1.12y = 27,480
then you have a system of equations
do you know how to solve from here
@neon iron
yes
@neon iron Has your question been resolved?
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.close
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excuse me
Well, just use $z^{-1} = \frac{1}{z}$
Alberto Z.
and i need helkp
for this
what is modulus
i dont get it
it doesnt explain what it is
It does
wat does it mean
That is the definition
Ahn you mean the geometrical meaning?
quadratic formulas give u roots of an equation
yess
Alright sorry didn't understand
In the end, it's an application of Pythagora's theorem to a triangle having Re(z) and Im(z) as sides
Because they help a lot in some fields, like physics and engineering
You can use them also to prove trig formulas
Imaginary is a bit of a misnomer
whats a misnomer
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hi im opening this in a new channel because mine closed since i couldnt get back to it in time hhhh
we had a quiz earlier and i js wanna see if my answers are correct, ive never encountered a summation within a summation so i wasnt sure how to answer it but this is what i put:
a) 10r - 14p or 10r - 13p
b) -16 or -18