#help-27
1 messages · Page 323 of 1
How is that related though?
wdym
Why is angle ACB just angle AOB divided by 2?
its a circle theorem
ok so like
take two points on a circle
the arc subtended by the two points from the center of the circle has twice the angle of the same arc from the edge
Is it the theorem that “the angle at the center of a circle is twice the angle at the circumference when both are subtended by the same arc”?
yes
this is one case of that
the other is when c is actually between a and b
please please pleaseeeeeeee never ask math to AI
So angle AOB is double angle ACB because of this theorem
yea
I’m trying to visualize this better
I see that angle AOB is found through its isosceles properties with angles OAB and OBA
we can prove it
do you see AOP and AOQ are also isoceles?
because again both radii
Ya
do u know the exterior angle property
BOP = OPA + OAP
BOQ = OQA + OAQ
the exterior angle is the sum of the two other interior angles
since OPA=OAP and OQA=OAQ, BOP=2*OAP, and BOQ=2*OAQ
soo
BOP+BOQ=2*(OAP+OAQ)
therefore POQ=2*PAQ
Very interesting
Wait wait wait so one last time in context of the original problem, the whole premise is that angle ACB is half of angle AOB due to this theorem?
Unlike this though ACB is such an awkward angle in relation to AOB
Like it has part of its angle sort of cut off for lack of better words
Is this part of no concern since triangle ACB encompasses triangle AOB?
ya true
sorry for the instantiation of 3D terminology
wait wait wait so for any problems like these
if an angle lies along the circumference of a circle in a triangle
a triangle “inside” the larger triangle with a point on the circumference is half the inner angle not on the circumference?
np
wdym by along
like on the circumference of a circle
ya
for example point C
maybe my interpretation was lost somewhere along the way
the solution is based off the exterior angle theorem right
WAIT WAIT WAIT
so just as AOB is double x
nvm
OH MY GOSH
ANGLE ACB IS SUBTENDED BY AB
AND THE INSCRIBED ANGLE THEOREM STATES THAT ANGLE AT CIRCUMFERENCE IS HALF THE ANGLE AT THE CENTER
AND WE FOUND THE ANGLE AT THE CENTER USING X IN RELATION TO AOB
@undone chasm
this is revolutionary
you should publish it
Mary
Angle AOB is found by noticing that triangle AOB is an isosceles triangle in which AO and BO are radiuses extending from the center. Noticing that triangle AOB is an isosceles triangle due to the fact that two sides of the triangle are equal to the circles radius, we can understand that the angles opposite to those sides (X and ABO) are equal. From this, we can conclude that AOB is equal to 180-2x. Now looking at angle ACB, we can see using the inscribed angle theorem which states that an inscribed angle on a circle is half the measure of the central angle that subtends or forms the same arc (which in this case, is AB, which angle ACB forms, and which triangle AOB forms). From this, we can deduct that angle ACB is half of 180-2x, or 90-x. We know that w + 90 - x is equal to 180 because ACD is a straight line. Rearranging for w: 180=w+90-x turns into w = x + 90.
I just needed to realize this
That the angle is related to the arc AB
thank you for this @undone chasm
this has bothered me for a hour
What math are you in now?
I see your pre uni
IS IT WRONG 😱
technically im in middle school (im >13 tho)
no it’s correct
but i like doing advanced math 🥰🥰🥰
are you taking high school math in middle school?
is this high school math?
I think the normal track for US high school students is to take geometry in 10th grade
oh what
yeah lol
I never took geometry 💀
I’m passing calculus 2 with flying colors now
But I’ve never seen this stuff before
I really like it though
I haven’t had a formal Euclidean geometry class though
my favorite thing in geometry was 2 column proofs
what are you learning rn?
wait what class are you in
somehow im in lhopitals rule after improper integrals 💀
we did that too 😭
im taking calc again to be able to take the AP
I believe it’s because limits are an important preface to take before series evaluation
They should’ve gone over lhopital before improper though
oh i see
Improper integrals are used a lot in series
we haven’t gotten to integral test yet lol
What country are you from 💀
Bro and you’re of middle school age JEEZ
What do you want to do after high school
I better see you at Wall Street
Or in the astrophysics department at mit
what do you want to specialize in?
either analytic geometry or arithmetic dynamics
being a professor seems awesome
very interesting
have you heard of differential geometry
I might take it in 3 semesters
I have to take real analysis first though 
I didn’t take geometry in high school but I don’t think that’ll be an issue
I don’t have enough knowledge to be able to make a comment on this
complex is the only complete algebra and it shows
so many edge cases in RA
CA is just like
wow
a path
Like as in no question is left unanswered?
wdym
By this I’d assume you mean there’s some areas of RA that are ambiguous and that this doesn’t exist in CA
yea
I see
They should take some ideas from physics and introduce ideas sort of like dark matter to explain the uncertainties
lol
I gtg
tysm btw
I wish u the best I’m sure you’ll go very far
have a good day!!!!
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cya and good luck again!! :))
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hii
technically, would the answer be 5?
well use pen and paper to check your work
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i was thinking like adding up two seperate integrals? one from 0-4 and one from 4-6 but thats not right. also im confused abt the equation for f(x) bc it doesnt look like the equation is just x?
from the graph that looks like sqrt(x)
it is
but how do ik that from the question
is it just a typo ?
oh yeah i looked it up and the college board question is sqrt
@uneven thistle Has your question been resolved?
umm no
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could anyone calc 1-2
this looks like something with arcsin(y)
how did u get arcsin y out of that
i said something
besides that iknow the derivative of arcsin
you can derive it using trigonometry
integrate then substitute and compute the upper and lower bounds
you compute the integral of the expression
then you subtract the lower bound substituted by the upper bound substituted
@safe nova Has your question been resolved?
I dont
understand what gizmic is saying
@safe nova Has your question been resolved?
No it hasnt and i wanna know too!
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Just for fun I was looking at this math problem where you take a tetrahedron shaped crystal consisting of one atom on the top layer, three on the next-to-top layer, six on the third layer, ten on the fourth layer, and so forth If there are exactly 1,000,000 layers, specify the total number of atoms in the entire crystal. Pretty straight forward however, I was told it could be solved on a pen and paper and without the use of a computer. My first thought was to just to take a cube with sides of a million (volume of a quintillion) and then find the volume of the tetrahedron in the cube but thats only aprox
I am trying to find a solution without using a calculator.
yes however theres a million layers?
hmm count isn't a great word
like
if i asked for the number of atoms in the 896,562th layer could you give me an expression that counts how many atoms there are?
it would be 896,562 + every number before it
yes
ok so the first step would be to find an expression for that
that doesn't involve 896,561 plus signs
n
the nth layer has the nth layer as a number + every number before it right?
then you do that for every layer
yes but we can find a concrete mathematical formula for the atoms in the nth layer
like without "and so on" or a ridiculous amount of addition
n * (n + 1) / 2
i googled it lol
i just ask bc everyone gets it in a diff way and i wanted to
oh ok lmao
so thats the formula
im not great at math but i like the theoretical side of it what really interested was finding a solve you can do on paper
now we need to just sum that for the million layers in the tetrahedron
oh ok
so then we can separate this into n^2/2+n/2
we use the formula above on the right one
sum(n^2/2)+n(n+1)/4
do u wanna figure out the sum for n^2 or should i tell you lol
isint it just n * n
hey boss I skipped school to drag hoses around for a living like i said im bad at math
gotcha
so the sum is n(n+1)(2n+1)/12+n(n+1)/4
now to simplify this
$\frac{n(n+1)}{4}\cdot\left(1+\frac{2n+1}{3}\right)$
blahaquil
ok and i just plug 1 million into n ?
$\frac{n(n+1)(n+2)}{6}$
blahaquil
yes
1 sec lemme open up desmos
it's 166,667,166,667,000,000 fyi lol
there exist sum formulae for all n^k
and thence you can predict your tetrahedrel crystals in any dimension!!!!
and theoretically this can all be done on paper
not just theoretically lol
i meant theoretically more in the sense of someone smarter than me can
hey i actually have to know some math for my job so im trying to get a little better but its mostly pressure stuff
yes
blahaquil
the sum of triangular numbers
ya
(you should type .close)
Ouch
@glacial sable Has your question been resolved?
defenitly broke it good thing it was my middle finger and not a important one
ahhh shit i cant play guitar
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Deez questions
Answers:
First: D
Second: C
Third: C
In the first question I can only prove the first statement correct
@molten birch Has your question been resolved?
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@molten birch Has your question been resolved?

😅 I'm getting ac > 3
For question #20, ACE + ECD will equal AFE. ECD is 60 degrees because thats an equilateral triangle. 60 + 20 is 80
Question #39, you should get 48 because the similar lines at AE and AB make two similar triangles kind of mirrored if you know what mean, and FCB = ADB if that's true
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HOW DO i do part a?
surely it's just that the resultant force on the plank is 0 bc it's in equilibrium
so i do force of boy down + force of girl down + force n = 0?
...yes
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!gethelp
Hello, I'm studying to take a G.E.D test, I'm curious if anyone could help me learn some of whats on this practice test.
These were the questions I don't understand
so the topics you're missing then are:
- volume of a cone (and perhaps volume in general)
- forming linear equations from an x-y table
- surface area of a cylinder (and perhaps surface area in general)
which one do you want to start with
Let's start with 2 & 3, I made a Google Doc to keep detailed notes, may I DM you editing access? The doc has been very helpful.
you want me to edit your notes...?
well, ok i guess i can at least take a look at them
DM's sent
May we speak in a VC?
ok yeah sure you've DM'd me anyway
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Are my choosing true ? Not a test just a bonus exercise
<@&286206848099549185>
all good
hey anyone here to help
hey does anyone know how to derive the magnitude of resultant of relative velocity of b wrt a my head hurts at this point i cant make any sense out of that formula and how it was derived
@terse bear Has your question been resolved?
Open your own channel
Also give more context
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how do i do 1 (b)
do you have PR
well you kinda need to know PR to do b
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?? ok
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i know z must be between 0 and 2 inclusive but im struggling to justify why using algebra and a geometric arguement. i was told that that i couldnt use the triangle inequality becasue u cant order complex numbers and then told that i cant separate the absolute value into cases so i dont know what im supposed to do??
i was told that i couldn't use the triangle inequality
says who?
like, yes, with complex numbers the breakdown into cases doesn't work anymore -- but the triangle inequality still does, and i would even argue it's much more visual in the complex case!
@smoky gyro
well i wasnt directly told but for my inequality arguement a helper said i cant do it like that because complex numbers cant be ordered
do you remember who that helper was
cause i think they were misguided
|z+w| <= |z| + |w| DOES hold for z and w complex
because, crucially, this inequality does NOT involve comparing complex numbers
the magnitude of a complex number is real
not sure
anyway, your geometric argument essentially is that |z-2| + |z-0| >= |0-2|, considering the triangle with vertices at 0, 2 and z
yes exactly
only if z falls on the line segment between 0 and 2 will there be equality
right
(and the "less than" case happens precisely never)
yes
we know this holds for every single z
correct!
yes
but how can i justify that z must be between 0 and 2? or is the diagram enough
the diagram is enough
okay
i asked austin how he would do it and he suggested that my inequality is in the form of an ellipse but itll be a line segment instead between 0 and 2
@weak cove is he talking about you
yes
ellipse with foci 0 and 2 sure yeah
yeah he's right
but ive never rlly worked with ellipses before so is the triangle inequality arguement enough
yes
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what is linear dependenced?
Do you know mutually independent? Its the opposite of that
Some linear combination of a and b gives you the vector c
if they are linearly dependent
something like ax + by = c, where x and y are some constants
Its similar, but somewhat tough if you wanna relate it to this. Just go with ax+by=c
o
This is a formal definition if you want one
yea
hmm but then what
but m and n are real numbers
how do I prove it
or am I just supposed to look at it and know
separate the components, and then solve. Its not tough at all
Yeah this is basically simultaneous equations with i,j,k as variables
do I do solve simultaneous
ye
for 2 equations for m and n
and then I sub into remaining one to see if the solution matches?
Yea
np
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conceptual question, when would you parametrize in cylindrical unit vectors as opposed to cartesian ones?
r(t) = (p(t), 0 , z(t))
r'(t) = (dp/dt, p*dphi/dt, dz/dt)
use another channel, this channel is occupied
Ok
@bleak arrow Has your question been resolved?
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.close
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I have no clue how to solve this, I have the answer but I just dont see how to get to it
<@&286206848099549185>
have u made diagram?
yeah
show?
,rccw
B1 and A1 are mid points
where the circle touches
i have to find AB
in expression with a and b
You got anything?
nope
sheet
trying to see if there is any property
theres one but i dont see how i can apply it
when the sum of the top and bottom angles is 180 and is equal to the sum of the side angles in the quadrilateral only then can there be a circle around it
ye the basic case for a cyclic quad
alr bro thanks for trying
I got something see if it helps
Draw all three medians
And try power of point on points A and B
with respect to circle
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1
how do i find the bounds
since the circle is on the right half of the xy plane, your angle needs to cover the right half of the xy plane
so you should do -pi/2 to pi/2
ohh i see
so its in terms of the quadrents
rather than the circle itseldf
it's easier to at least think about the quadrants to find the bounds
eyeballing it usually works luckily
but sometimes you need to do more work to find your bounds if the shape is really complicated
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i need help with this
I forgot the ^2
almost
the bounds of the integral are correct
though i do recommend replacing them with like $-\alpha$ and $\alpha$ or something and note to the side that $\alpha = \arccos(1/18)$ or sth
Ann
anyway the integrand should be $(18 \cos(\theta))^2 - 1^2$
Ann
yeah ok correct integral now
Yea
this is correct thus far i think yes
seems ok but why b and a in the last line
u said to use that
the alpha and beta
oh
did you read something that didnt exist
how did arccos(1/16) happen
also more importantly
you're asked for a decimal answer
why are you not using a calculator
or hell even desmos at this point
thats suppose to be a 18, the circle was just too small
im trying to put it in desmos rn
what other desmos thing were you thinking of
are you just using its standalone calculator
desmos graphing calculator is very powerful
how do i do this
the scientific oen?
do what
anyway yeah ig the scientific one doesnt have the integration stuff
i was trying to figure out how to enter it, but then i saw how u did it
entering stuff is fairly straightforward in desmos
i think i did something wrong
didnt work
maybe it rounds off to nearest integer
it says 3dp
.... i would flag this question somehow tbh
im not seeing where we are both going wrong here
where does 323 come from
oh mb lol
OH
MY FUCKING
GOD
WE BOTH FORGOR TO HALVE IT

theres a half
that we both just completely forgor about
divide that shit by 2 lol
252.935 should be it
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Maybe a small question, but i can't seem to understand how i am supposed to explain how the projection of vectors formula can be used to find the direction of a vector, when it is reflected of a blank surface
i have proved the formula, but i can not seem to understand how it is used. When googling i keep getting redirected to other formulas that i highly doubt that im supposed to know for my assignment
and help is appreciated
I thought about using the orthogonal vector instead to find it, but i did not come far with that
my vector is (1,2,3) and the plane im given is 2x-3y+z=4
and so i figured the orthogonal vector would be (2,-3,1)
which i then substituted into the projection of vectors formula ,but im not sure of where to go from here
I mean that im supposed to explain(in text) how it its possible to use the vectorprojection formula to find the orthogonal line that is reflected of a blank surface
but it seems as if the vectorprojection formula can only describe when the vector is going to hit the blank surface
not the vector after it is reflected orthogonally
i hope that makes more sense
kind of. I have to use the projection formula to explain how it can be used to find the orthogonal line
that's what i did up earlier
but im not sure of where to go from there
Yeah
no
the thing is im not allowed ot use the reflection formula in the wording of the problem
hmm ive drawn it out on paper
I agree
my teacher has been known to make mistakes, but she is nice so it's alright
the question is unfortunately in Danish and hard to translate, but at least im glad im not the only one who finds it vague
Oh nice 😄
Swedish+
?
Ah alright
not quite its more like the projection comes down from up top and lands and is then reflected out orthogonally
It's a final project for Danish A level math
Im trying to draw a beautiful rendition in paint
yeah i do get it
my problem is just how to use the projection of vectors formula to calculate the angle of the green reflection
ey thanks anyways
ill see what i can do
<@&286206848099549185>
i am still stuck on my problem that is mentioned above^
any help is greatly appreciated
!status
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Trying to find the volume with the following constraints. If I wanna start with dz, the limits would be -sqrt((x-y^2)/2) to sqrt((x-y^2)/2), to find the 2D region R when the triple integral reduces to a double integral, can I just set z = 0? or do I have to set the two z's equal to each other?
@bleak arrow Has your question been resolved?
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Triple integral of what?
Oh
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suppose i want to calculate the integral of sinz/z over a unit circle
Please don't occupy multiple help channels.
suppose i want to calculate integral of sinz/z over a unit circle
i guess that is called residue
$\oint_{|z|=1} \frac{\sin(z)}{z} \dd{z}$?
Ann
Yes
but the radius of circle wont effect outcome
so i take radius very small
then use sinz=z-z³/3!+z⁵/5!-z⁷/7!...
i mean sure
sin(z)/z has only a removable discontinuity at 0
you will find that the residue is just zero and so is your integral, won't you
but integral is 2π
Orginal question was to integrate sinx/x from 0 to infinity
...
i do it from -infty to infty
what an XY 💀
so the integral over that top contour should still be 0 yes but you can't really take the limit as R -> infty here
because $|\sin(x + iy)| \approx \sinh(y)$ for big $y$
Ann
ummmmmmmmmmmm
sintaxis error
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maybe that helps
https://www.youtube.com/watch?v=8x_UjFUySRg
We look at spherical coordinates, describing regions with spherical coordinates, and converting dV into the appropriate spherical coordinates expression. Imagine looking at a globe. The surface of the Earth, being roughly spherical, is mapped out using a grid of latitude and longitude lines. Latitude measures how far north or south we are from t...
one thing to be careful about is that different conventions swap the role of theta and phi
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can we derive a method to tell if a given cubic is monotone by analyzing the sign of the general form of its derivative?
like is there some relation 3a, 2b and c must have that means 3ax^2+2bx+c > or < 0 for all x?
Recall the discriminant (specifically for a quadratic)
negative determinant lol
thats what I just found too
ok I think I got it
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if anyone is free I could use help figuring out mathematica code for this line integral. I missed a week of class and my professor is out rn, so I need help learning the theory/correct way as well.
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where do I go from here and is this right so far
oh okay
Looks right so far
First term looks like a trig sub
Second I would say integration by parts and then a u sub
i cant just do trig sub for the second one directly?
3rd is probably also a trig sub, but Idk, I would check
Is there a trig sun that works well there?
idk i kinda forgot how it works lol
Lemme see
Actually it probably would work there
But I think you'd end up with some sort of product of trig functions, you should check first though
Do you need a reminder on trig subs?
yeah i dont remember how it works
ill just watch a video or something
thanks
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This is the question
I don't understand why you are trying to do this
just set up the triple integral first
i already did
for dz
-sqrt((x-y^2)/2) to sqrt((x-y^2)/2)
i'm trying to get the projection
z ranges from -sqrt((x-y^2)/2) to sqrt((x-y^2)/2)
so then what do your y and x range from?
can i just set z = 0 to find the domain D?
no
set up $\int \int \int 1 \ dz \ dy \ dx$ with the appropriate bounds
south
so I set them equal to each other?
no
well how I would proceed is $y^2 \le 8 - x \implies 0 \le y \le \sqrt{8 - x}$
south
I already know how to do double integrals. I'm just trying to get the region R here.
from the constraints
I know, and I'm helping you with that
I've bounded y for you
I guess if this helps you
pictures help a lot
wait hold on sorry
I assumed x >= 0 but like
the region in the original question is unbounded I bet
hopefully I'm not making some silly error
oh wait, any sum of squares must always be positive, so 0 <= y^2 + 2z^2
so yeah that forces x >= 0
my pattern recognition lit up and assumed something without me consciously realising why
$y^2 + ( \sqrt{2} z)^2 \ge 0$ to be extra clear for all $y, z \in \mathbb R$
south
do you agree that the region is given by the following equations:
x + y^2 <= 8
y^2 <= x
y >= 0
My question is, how did they arrive to these equations. x + y^2 <= 8 and y >= 0 are given, but how did they arrive to y^2 <= x?
so that you have 0 or positive <= 0 or positive for y^2 + 2z^2 <= x
should be y^2 <= 8 - x
that's a typo in your book
oh right, well you can make z range from 0 to sqrt((x - y^2)/2) then don't forget to multiply the original interval by 2
it's an argument by symmetry
case a) with the function being 1
if u set the two bounds for z equal to each other, u also get y^2 <= x
but I think worrying about such tricks is confusing you
u just graph it right? u don't use these tricks 😆
yes
just graph it and $0 \le y \le \sqrt{8 - x}$ and $0 \le x \le 8$
south
I hate graphing in 3D.
you don't need to graph in 3D!
then how do u get ur region
your whole point about graphing the 2D region after the z-bounds was correct!
z ranges from -sqrt((x-y^2)/2) to sqrt((x-y^2)/2) is correct
then you just need to bound x and y
how do i get the 2D region
so you need to graph the region where $x + y^2 \le 8$ and $y \ge 0$
south
forget about it
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why? don't we wanna get the 2D region? isn't it a constraint? in the solution they use it
oh they've done a different order
AH okay so $y^2 + 2(0) \le y^2 + 2z^2 \le 8$ and that's how
then if you plot the region you will get that y ranges from 0 to sqrt(8), oh but there's another restriction cause of z arghh
not -sqrt(8) to sqrt(8)?
fair enough it's good to think of it from multiple perspectives
nope, look at the graph again
wait
the graph isn't the only story
south
yes because if $z = 2$, you get $y^2 + 8 \le x$ but you also have $x + y^2 \le 8$ remember
so that's the limiting case, $y^2 + 2z^2 = 8$ exactly
south
i got this
ah so yeah when you combine all the restrictions you should use your graph not mine
so u basically set z = 0
yes so any time you see z^2, z^4, z^6, z^8 and so on
those are all squares
so i set z = 0 in these cases?
z^2 >= 0, z^4 >= 0 for all real z and so on
yes!!
well you set z^2 = 0 or z^4 = 0 which is just z = 0
so same thing
yes so there's a hidden limiting case and that's why
it's so messed up
oh yeah absolutely
so z^(1/2) and z^(1/4) and z^(1/6)... too
because there was one problem where it's wrong to use z = 0, do u wanna see that example?
"Find the volume between x^2 + y^2 + z^2 = 9 and z = 1/8 (x^2 + y^2)"
Here we can't just plug in z = 0.
even though our z is squared
oh that's best done in spherical coordinates
i know but if we did it in rectangular we can't plug z = 0 to get the region
I think it just comes from subbing in no?
wait
basically you should try to replace x^2 + y^2 here
so you get 8z + z^2 = 9 and that's very different now
why I tell you not to use Cartesian is because r^2 + z^2 = 9 and z = 1/8 * r^2 is much easier to see, how to proceed
yes
like of course you must have z >= 0 because z = 1/8 * (never negative)
but there's an even stricter condition
now you know what values z is exactly
from subbing in
try to sub in whenever you can, random things
if you can solve for something, solve it
otherwise you're just left with the default assumption that z^2 >= 0
i think here for z = 1/8 (x^2 + y^2), we can't just plug in 0 as x^2 + y^2 = 0 doesn't make sense
so in that example, z >= 0 overlaps with z = -9, 1
you reject the -9 and you're left with z = 1 only
yeah that's not a limiting case, z = 0
you already know what z can be in that situation
so you have to instead figure out which z values are possible
i see
I lied obviously knowing this now use cylindrical
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Yoo
Can someone help me with basic calc
sure
Send the question first so bot pins it
It's not a question tho. I mean ok
That's a long question
frfr
Yo Sorry, give me some times I'll make the question and be right back
Lol he's been typing for 5 minutes
It's my personal question actually..
😭😭
:(
and I can't think how I the fck I ask it
..
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$\lim_{x \to 2} \frac{\sqrt{x} - \sqrt{2} + \sqrt{x + 2}}{\sqrt{x^2 -4}}$
MOD BY ZERO ERROR
Yee
hmm
im assuming u cant do a cheap graphing or numbers close to 2 being plugged in thing right
Yes
gimme a sec
So no calculator, right?
Yes
cuz its defined for 2+ but not for 2-
Yes
Hmmm
Have you tried doing difference of squares on the bottom then partial fractions
Yes
id just say dne cuz lhs != rhs
Wait wait wait
I'm being silly
The bottom has a higher power of x in it
So it has to go to Infinity quicker
oh wait yeah lol
wait no thatd mean it goes to 0..?
Meaning this will asymptote
Oops yeah
Ans is 1/2
???
@leaden star yeah idk about that one
Photomath also says that
the answer is def not 1/2
But it does it with lhopital
Ummmmmmmm
photomath probably copied it wrong
,ask $\lim_{x \to 2} \frac{\sqrt{x} - \sqrt{2} + \sqrt{x + 2}}{\sqrt{x^2 -4}}$
Wolfram Alpha doesn't understand your query!
Perhaps try rephrasing your question?
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oh wait
its minus
i copied fn wrong
$\lim_{x \to 2} \frac{\sqrt{x} - \sqrt{2} + \sqrt{x - 2}}{\sqrt{x^2 -4}}$
MOD BY ZERO ERROR
yes it's 1/2
What did u do diff
lemme find an algebraic manipulation
i put a plus instead of minus
you do partial fractions yeah
Ok but why does the limit exist
Im not sure what that is
We usually rationalize and then evaluate for the denominator part of the diff of squares
Ill write it out
\[
\frac{\sqrt{x} - \sqrt{2} + \sqrt{x - 2}}{\sqrt{x^2 -4}} = \frac{\sqrt{x} - \sqrt{2} + \sqrt{x - 2}}{\sqrt{x - 2}\sqrt{x + 2}}
\]
\[
\frac{\sqrt{x} - \sqrt{2} + \sqrt{x-2}}{\sqrt{x-2}\,\sqrt{x+2}} = \frac{\sqrt{x} - \sqrt{2}}{\sqrt{x-2}\,\sqrt{x+2}} + \frac{\sqrt{x-2}}{\sqrt{x-2}\,\sqrt{x+2}}.
\]
MOD BY ZERO ERROR
the first addend approaches 0 and the second addend approaches 1/2
do you see that?
$$\lim_{x \to 2} \frac{\sqrt{x} - \sqrt{2}}{\sqrt{x-2},\sqrt{x+2}}$$
Let $h = x - 2 \implies x = 2 + h$. $x \to 2$, $h \to 0$
MOD BY ZERO ERROR
and i think u can work out the rest
second addend goes to 1/2 by cancelling sqrt(x-2)
do not rationalize
you need to split your fraction like this
Right but we havent done partial fractions
I know what it is , you do A/... + B/... and solve
But is it possible with just rationalization?
I figured it out
Really simple
Want me to send you a pic
With just difference of squares
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I am unable to get the correct answer, maybe it's brain fog,can smone help me?
<@&286206848099549185>
Idk if whatever I have done is bs.
But can someone guide me, please?😭
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Saying that $|e^{-x} | < 1 $ is incorrect
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Hello, Need determinate value of g(0), Please and ty for the help
How would you approach this problem?
I really don't have much of an idea, I'm a bit desperate :(
I don't just want the answer, I also want how to solve it.
Well you need to read the value of graph g when x is 0
!noans
The purpose of this server is to help you learn, not to hand out answers. Do not ask someone to give you the answer directly.
oh
i can't read 💀
but yeah uh
you need to look at the green curve and specifically at the point whose x coordinate is 0
Can you identify where x = 0 is on the x axis?
I promise I'll try, but I don't know. Can you be more specific with the question?
I'm very sorry, I'm not very good at calculus.
Or could you explain it to me in another way?
this isn't calculus

