#help-0
1 messages · Page 848 of 1
ahh hmm
notice you are given A and B, 2 points on the circle
yep
You are told the centre of the circle is on the x-axis
i can find the equation of the line
so one thing for sure is
yes therefore x is something while y=0 right?
yess
so what can you tell about the lines that connect A to the centre and B to the centre?
should be doable from there
Ohh i can find the gradient of A and centre and gradient of B and centre
no need
C is at the same distance from A than from B. It is true for the midpoint of AB too
What is the line that goes through both ?
Yep its besically intersecting circle C
Ahhhh okayy
Your perpendicular bisector intersects the x-axis at the center of the circle
Ohhh
let me try work it out
hi can anyone help me solve this one https://cdn.discordapp.com/attachments/509460208737845248/897272369893220372/unknown.png
@vagrant flax the other method which i was talking about is to realise that the two line segments connecting A to the centre and B to the centre are the radii, so they have the same length
Yup, works too, but they asked him to find midpoint of AB, so I guess he learned in class that the perpendicular bisector is the line with points at equal distance
So he could find this way by thinking a bit
Ohhhhh i get you, you use them to find X, distance formula is needed for that!
Melo thankyou so much, i got x=9
yup, both methods work
Ken G thankyou soo much too!!
i just listed the one that came to my mind first lol
i have no idea how this is wrong
-(n-3) = -n+3
You got tricked by the sign
the exponent of x should be -n-3, so n+3 if you put it in the denominator
the error is in n-3
Yep!
yep its n-3
uhh i might need to redo it
i dont really understand the problem through reading lmao
sure if youre willing to lol
Hello, I need a bit of help in here
$$lim_{x\to\infty}\frac{(7-x)(3+3x)}{(3-2x)(11+7x)} = lim_{x\to\infty}\frac{21+18x-3x^2}{22-x-11x^2}$$
this is the furthest I’ve went - I don’t think it’s possible for me to factorize back in a different form or use the polynomial (?) technique and find 3/11. I know I can use l’hospitals easily, however I wasn’t taught that in my course yet so I am looking at alternative ways to find the answer. Can anyone drop some hints as to what I can possibly do next?
divide through by x^2
or that
rolla
$\lim_{x\to\infty}\frac{21x^{-2}+18x^{-1}-3}{22x^{-2}-x^{-1}-11}$
Mosh
leaving 3/11
that's what I tried to do... but for some reason it wasn't accepted as an answer
Mosh
so yeah, double check your expanding, then it's just read off the leading co-efficients
in general $\lim_{x\to\infty}\frac{f(x)}{g(x)}$ where f and g are both degree n, the limit is the ratio of leading co-efficients
Mosh
proof is similar to the trick of dividing by x^2, just instead use x^(degree of f and g)
for what values of x is f(x) < 0?
8??/
can i get help with b
not a
a is 30 and i know
What does the "f(x) < 0" part mean
Can you try to figure that out first?
what value of y is less than 0
Close, the question is basically saying: "what values of x make the result (y) < 0
So at what point in the graph is y < 0?
Ok @small hatch I assume its asking for an interval
So x = -7 would give a y result < 0, yes
but
There's also infinitely many others
So you actually have to give me a range
Ok I guess thats how they want you to do it
So then yes that's right
Just make sure to put x = -7, -4, -2, 10
okay one sec
if it was 0 <= 0 it would be included
Yea
alright
so then when it asks for greather than
Normally teachers would make you give a range
i make the points above the 0?
this is another problem she did
Oh yeah thats just plotting the graph of a parabola
Do you have any questions for that?
no thats simple really
I don't know why she makes you give individual points though
i have a question for a diff one just give me a bit to get to it
because there's technically infinitely many points
when f(x) < 0
It's the RANGE that matters
Like from (-8, 0), f(x) < 0
yeah she teaches weirdly, not sure why
The "(" and ")" notation means it's not included
okay how about this:
If f(-5)=f(b) and -5 ≠ b, what is the value of b
@flint badger if you're still available
yeahhhh same.... 😂
I'm not getting this
Is there anymore information provided?
I really don't get what they're asking here LMAO
OHH
Hey guys where the negative go
I completely forgot you were using the graph before
also I believe you put f(0) and not f(b)
oh yeah oops 💀
do you guys know this?
okay
Because you can evaluate that right
f(-5) is basically just saying: "If I plug in a value of -5 for x in this function, what y value do I get?"
correct
So what is f(-5)
0?
Not quite
it doesnt have a point on the graph
If you put -5 for x into the graph
What corresponding y value would you get
Imagine it's (-5, y)
Try to figure out what y is
it looks like -4?
how though?
So now you know what f(-5) is right
the point isnt marked
okay
In the other question the points did matter
Because she was asking which points were below 0
And she was asking for the x value of those points lol
So you know f(-5) = -4
egg dog when you get a chance could you help me?
Yeah sure
okay i just need help evaluating a few questions
f(b) = -4
when you’re finished
-4?
so the value of b is -4
sort of
What are you confused about
let me check
b and x are just the values you plug into the function
again
,rotate
.rotate
whooos
um is ir okay if we do a few
Yeah
i think i have 2 other questions okay
Yeah we'll get to those, so just think about what g(3) means
(3) would go where x is correct?
Yes so
every function has a name ok,
this one is called g
and it takes in an input, x
ok
yup
So it says if I put in an input of 3, what will I get
In other words, if I set x = 3, what do I get
So yes, you're replacing x with 3
alright yeah i understand so far
So just plug in 3 for x, and then evaluate it
wdym
$g\left(3\right)=2\sqrt{4\left(2\right)-3}+3$
Should look something like this
Oops not 2, I meant 3
bruh
wait
lol
$g\left(3\right)=2\sqrt{4\left(3\right)-3}+3$
eggdog
You're still evaluating g(3) right
yeah that’s what i was staying to say
You're not done
okay
Egg how are you still going at this 😂
egg are you still in hs?
Which equation represents the line that passes through the point (1,5) and has a slope of −2?
Yeah
Yeah he helped me at 10 this morning and it’s now 8
@chilly spruce Hold on this channel is occupied
Try asking it somewhere else, but dont spam every channel
ok sorry
basically plugging in 3 right?
Yeah
yup done
okay should i come back with my answer?
Yeah
alright
Sure
i’m sorry egg what would 4(3) be?
oh okay
Wouldn’t it just be 0 since it’s halfway
how do I find where this is continuous?
So you know g(-6) is 2 right
@tardy plank sin is continuous everywhere,
isnt it 3
No that would be
g(-8)
Wouldn't it
At -6, y = 2
So where else is y = 2
or in this case, g(b)
how did you get 6?
Could you take a picture of your work
@buoyant edge how would you use algebra to prove that in this case though so I can figure out other similar problems
$\sqrt{ }$
eggdog
you mean this?
yeah
That is a square root
okay i forgot
@woven river I would suggest first knowing what these operations are before tackling these problems
let me redo this
how would y = 2 at -6? wouldnt it be at -5?
Do you know what a square root means?
@tardy plank look up proof that sin is continuous; you need epsilon-delta definition for that
yeah i do
oh im sorry
I misread the graph
smh im sorry
you're absolutely right
no I would say at g(4) its pretty close to 2
OH MY GOD
im actually stupid
ok you know what
what happened 😂
haha
g(3.5) would be close to 3 yes
okay, thank you!
1.5 would also work @small hatch
oh as well as -9, they'res a bunch of points before it
that still give you an output of 3
-9 has a point, does it matter?
How'd you get it
okay
$g\left(3\right)=2\sqrt{4\left(3\right)-3}+3$
eggdog
If you evaluate this properly, you should get g(3) = 9
thank you so much eggdog! great pfp btw
Which means that if we were to graph this, an x value of 3 would give us 9 as the output
np
what grade r u in btw? you said youre still in hs
Im a sophomore
oh damn.. what math classes u taking!?
Calculus II atm
wtf youre actually crazy smart
Nah nah lmao
yesss whaat... i take pre calc next year (junior year)
@woven river Sorry I have to leave right now
this is how
You forgot about the -3 + 3 part
cya!
4(3) = 4 * 3 but there's still the -3 inside of the square root and the +3 on the outside
Bye
oh shoot
See if someone else can help you, I have to eat dinner
Bye :/
how did you go from 4(3)-3 to 4*3 under the root?
the +3 is on the outside of the root, right?
well you can't just bring a number from outside the root inside the root
3
so now you have 2(3)+3, right?
yes
and what is that?
9
right
i'm not sure what your question is
okay let me post
alrighty
sure
let me get them
At which points tangent line to f(x) = 1/(x2 – 25) is horizontal and at which points is it vertical?
yup got that
the root?
yes
right
so what's 3(-1)?
2
a disappointing son
a disappointing son
sorry internet uh 16?
remember your order of operations
parenthesis, exponents, multiplication and division, addition and subtraction
which one comes up first?
i meant in the order that i posted
parenthesis
yeah
does the -1 need to be changed?
yes
anything happening to that in the parenthesis?
are you sure?
it's just the -1 in parenthesis there
nothing else is with it
then no
exponents
see any exponents?
yes
yes
what is it?
we can rewrite $(-1)^2$ as $(-1)(-1)$
a disappointing son
yup
what happens when we multiply a negative by a negative?
positive
so what is (-1)^2?
1
This is crazy @buoyant kayak now that I just realized what your pfp was I cant unsee it
4
correct, so now you have -3+4-5
I dont know how but i didnt notice it at first, anyways sorry to interrupt
now you can just add and subtract from left to right
egg i'm not sure what you mean lol
yeah
my pfp is my friend from high school
I didnt notice it was a face rotated 90 degrees counter clockwise
-4
right 👍
how do i do this with steps?
That means for every billion parts you take, 8 of them are lead
sure
one moment
it’s find the intersection between the filling functions algebraically
a tad blurry
sorry
,rotate
alright, so you want to know when these functions equal each other
yeah you're good
after he's done
so for ur problem replay
if you want to find the x where they intersect set them equal to eahc other
so if you want when these functions equal to each other, what do you reckon you should do?
Hey
k
still lost
Can someone help me
op im next for help when im done u can put question
Ok
you'd call this systems of equation right
yeah
generally there are 3 solutions to it
infinite solutions
one solution
or no solution
can you guess when there would be infinite solutions
yeah
when
think about it
if you have two lines that intersect at every single point
there is only one way for that to happen
they'd have to be the same exact line
i don’t i’m sorry
nah ur good just trying to help
it would be when they have the same slope
do u understand why
like if you had 2x+7 and 2x - 3 and graphed it they would never intersect
oh
because from 7 and - 3 they would go up or down the same amount and never touch
i understand that
ok now we can go to the problem
so you'd set them equal to each other is the first step
reasoning behind it is
they are equal to each other at the place they intersect
yup
so would i have to find f
first
then plug that into g
sorry if all over the place
you'd find x
yes
f and g are two functions
i meant x im sorry
x is the same in both f and g when they intersect
so solve for x then plug it into either one for y and you have the location of where they intersect
ur good
i’ve gotten through ap psych and remember i had alg 2
yeah i guess lmao
call ap psych ap quizlet
can someone help
alright i have it
what'd u get for x
one moment
Very quick question, how can I explain that I know two ratios are equivalent?
if you simply both they are the same numerical value
ex 3/4 6/8 both simplify to 0.75
idk if thats satisfactory
okay um 1?
yea
and plug that into f or g
and you have the location of the intersection
ur done
1,-3?
ye
np
looks like you guys are finishing up, i dont want to interrupt so just lmk when you're done
calc ii
you’re senior?
nah college freshman
oh
bro someone help me
yeah i have a kid in my class ima sophomore and he takes ap clad
calc
it’s nuts
like how the hell
at my school ppl took it freshman year 💀
but its a magnet so it makes sense
i took it junior
👍
nah ur good
all my friends take pre clac
u can try to skip/catch up over the summer
but then i’m taking 3 aps so it’s killing me
op how hard is ur question
i def will
Huh
Ik I just forgot
I forgot the formula
use f= ma
F= MA is the most important physics formula bro
nah u gotta be taking physics 0
jk
physics is gonna get real later on
This is my first year doing physics
what'd u get
ur good then
Can someone help me?
how hard
we went from basic arithmetic and algebra to calc 😭
RIP
i came here for calc help too cuz i havent done it in a min
related rates problems are so hard lol
annoYing
i can try to help
probably won’t be of much help though lol
anyways give me a minute
Try to graph it
i don’t see anything wrong so idk
maybe go though it again and pay a lot of attention?
dang i forgot what its called
tangent line is horizontal when the function changes from up to down or down to up but its. abit more tehcnical
its been a min
prolly false though
i think you could have horizontal tangent lines with no x intercepts
@mental hearth sounds right
is this about my problem?
yes
oh I've done it 3 times, I get the same answer and the website says it's wrong :(
go through it again and pay a lot of attention maybe
i’m not very good at these either
its vertex form ibut idk how i should do
@dry echo wait i have a stupid idea but i’ll try anyways
I have one try left
<@&286206848099549185> i helped two ppl and im down bad 🥺
need help w this
oh ok
man, how am I gonna pass calc 1
i was gonna say you did the derivative of the radius instead if the derivative of the diameter, but idk if that matters
probably not
yeah you should wait for someone else instead of doing my ideas lol
isn't that what I'm supposed to do? since the formula uses radius
idk it was just an idea
actually scared to plug it in tho
i don’t blame you
ok so now the question is
do I plug the negative
or the positive since the question already asks for decreasing?
nah im gonna take an L on this hw there are 11 more 😭
i’m trying to differentiate it, just a minute
aye bruh it be like that sometimes 😭
can someone walk me through how to convert y = ax2 + bx + c to vertex form symbolically (just with variables, no actual values?)
I submitted
my hw is similar are we in the same class 👀
nah its not
And almost got it right, shouldn't have plugged in the negative
jesus christ
@raw shard Take a look at that lol
I mean it is decreasing so I thought it should be negative

hallo i have a hemisphere of radius R and i have to integrate over all the vectors in it. i declared that if i look at it like stacked disks all the horizontal components cancel so to get the vertical component i just do integral from 0 to R of pi r^2 * r dr
is that legit
i dont really know if the integral i wrote makes sense but the spirit of the question is to basically get the average vector in the hemisphere
It's legit.
kool
You're just applying spherical symmetry to 1/2 a sphere 🙂
guess so
should have been tipped off when the question said the surface area was decreasing at a positive rate prolly
The question asks the rate at which it decreases so it's assuming we don't need the negative in our answer
it says the rate at which it decreases
Yeah
well i almost got it right lol
Either way, I'm glad I found the correct way to solve this
WIth your help @raw shard
thank you!
yeah that was hard for me too
way too many chain rules right there
implicit differentiation and normal chain rule in one
yeah lol
What made you think the first limit is 21?
Hi @buoyant edge
21 is a mis input, the only correct answer of these is F(3) = 3
I was messing around with the system to see if it would give me minus points on wrong answers
For the most part, I'm confused on the different lim-->x notations and how to read the graph.
Well let's start from the top
Hey, from A ∈ R^(n×n) and xT(Ax) > 0 for x ∈ R^(n×n) except x = 0, and A symmetric, how do you prove that A is invertible (and thus the rank is n)?
Channel is occupied.
lim x --> -1^-
That means x is being approached from a upwards angle, is it not?
- means approaching from below afaik
"downward angle"? it just means that we're approaching -1 from the left
So our test values are getting bigger
yeah my bad, I mean to say that we're traveling upwards as the values increase due to the slope of the line
I understand this, but my issue is what to look for here. There are two lines on this graph
Yes, that's a jump discontinuity
I see
So the limit will not exist there.
Does that mean the answer to the question is DNE?
Not to the first one
I'm so dumb, you're right
At -1 you will be approaching 1 from a value greater than 1, from what I understand.
Yes.
How would I note that as an answer though? x>1 ?
It's just given by the graph. These are things you can tell by inspection.
Clearly, F(x) is approaching 1 as x gets closer to -1
Yes.
Since it approaches 1 as x approaches -1 from the left and from the right, the limit exists.
and is 1.
Understood
You're asking if there is a hole at the limit, then the limit does not exist?
This is my progression so far btw ^
yes
No, that is not true.
Regardless of what the function's value is at that point, the values around it are approaching that value.
And that's what a limit tells us
What the function approaches
So, for x = -1, clearly the function value gets closer and closer to 1
but F(-1) != 1
That doesn't matter here, though, because the line tells us we are getting closer and closer to 1, which is what we want.
Make sense?
Yessir
Chris24
Am i to click the right answer as a reaction?
Ah my bad, yeah
Look at the graph: as we approach 1 from the right, where is the function going?
towards y=4
Nice.
Cheers mate, i've finished the question
I'm just going to take some notes of what you've written
Nice job!
May I post more afterwards or is there a limit?
As much as you want! Just try to be courteous to others (i.e. don't interrupt channels when others are working together).
Understood, should I give this channel some time for others to post or go ahead with the next one?
I have some problems regarding continuity / other limit functions
It's not that strict: if it looks free, it probably is. If it's not, someone will let you know.
Alright, i'll post them here
Sounds good.
The thing to note here is that I have never done a question as such. I've learnt about limits just today, but my professor dropped this in our homework and I am somewhat confused. I can definitely discern each of the functions themselves as a separate x value of f(x), but what is with the braces "{" and how do these work?
Should each function equal itself, as in 8-x-x^2=2x-3
Where I then plug in the limit?
Those braces define a piecewise function
I understand that x-> 4- is -12, 4+ is 5, but what is the third (x->4)
So for certain values of x, the function is defined one way, but for other values of x, the function is defined another way
DNE
Since the limit is not the same from both left and right
The function doesn't "settle down", so to speak
I see, so in this case it's about the function producing two differing graphs which cannot meet at one point where x=4
Yeah, that's the idea
That was much easier than I thought, for it being something I was unfamiliar with...
Since the limit is not the same from both sides, it does not exist
I have another question in this problem set. I've used what you taught me to deduce #1, #3, #4, and #5. #2 should be DNE because there are two function lines at f(1), right?
Note that -1 and -3 seem to be incorrect as well(?)
Nope, it's -3...
Could you perhaps explain why in this case?
The software notes that f(1) = -3 is a correct answer
it is
But why was it -3 over -1?
you see how there’s a whole on one of the graphs at 1?
and not a hole anywhere on the other graph
it isn’t defined there on the blue graph
it is on the green one
I see
remember this says nothing about a limit, just what f(1) is
The hole means that it doesn't count as a limit and the solid circle should be the one noted as the answer?
yes
Understood, i appreciate it
no problem
This seems more confusing due to the -INF values. What does it mean by continuity on (-INF, INF)?
@craggy niche pretty sure it means it’s continuous everywhere
How would one note that as an answer though?
what exactly do you mean
I don't understand what you mean by that, and how i would note that as an answer on my quiz :/
It's continuous everywhere, yet what do i write as the answer? It's asking for a single value for some reason
"DNE" and "INF" are not valid answers it seems
basically what value of c makes 16-c = 4c+5
Excuse me
what
I need a bit of help with inequalities
this channel is occupied, go to another one please
i can help in a minute
although i can’t guarantee i will know how to do it
I see, so this should be 2.2
That was correct. You found that by equating the two functions to themselves, right?
ok, i've written it down as a note. Thank you
no problem
Hey simple question
If there are 436 Water Tiles
And Feebas only spawns on 6 of them with a 1/73 encounter rate
Would that be written like this? (1/73)*(6/436)
Or like 1 - ((72/73)*(430/436))?
What would this calculate?
Confusing myself 😂
i just put it in math terms as i read it and got what you first sent
Ok gotcha, but when do you do the 1 - (...) ?
sorry i don’t know, what you sent just looked right to me so i said yes
Oh no worries 
youtube prob :p
most likely
i think remember seeing you a long time ago back when i was into pokemon
this seems like it would make sense
i mean im no genius at math
i see things if they work then they work
and this just kinda seems to work
sorry isn't your discussion over? if its not i can delete my post
can't see why you can't keep it up
ah okay ❤️
hello
i have problem understanding left inverse injective and right inverse surjective
i've been reading the proof for couple of times, i know the definition of surjection and intection
if we call f:A->B and g:B->A
what is the Identity function here calling it I?
is I the same as Id_A?
is f^-1=g? why i didn't see that notion here
how does the right inverse work? if set B be surjective but not injective, then it can share some same range in order to surject (we can't use D-{something}), so then if A wants to imaged to B then one element of the domain goes to 2 or more elements in the range, which is impossible
are we using some of the elements?
why can't f be surjective if right inverse does not exist?
if a=!b but f(a)=f(b) it still is surjective but right inverse doesn't exist
if right inverse in a surjective function of A->B->A exists (B->A be g) then it must be bijective
“write cos x in terms of tan x” it gives the pythagorean identity, then the next step is to “take reciprocals”.. how come?
go another channel mate
wait f^-1=!g ? cause we are taking some of the elements from B
if f:A->B be surjective then g:B->A cannot be also surjective or its not a function at all
so function g is limited/reduced of f^-1? (that all of the set B images to A but doesn't surject A)
and selected elements from b get imaged to themselves like identity function, but not all elements in b get imaged to themselves
could anybody please help me, been waiting for 1 hour in question 1
can someone just tell me what n means in this case?
i am very much a beginner
I am learning sets right now
Could someone please help me on providing this identify
i think your question is missing some information
You only have to explain how to solve an infinite geometric sequence
You don't have to solve it
there are probably parts
i)
ii)
conveniently cut off
any even number so 22/100 can be
Post the full question, if that is the full question skip it because it isn’t actually asking anything
Yeah like I said whoever wrote it forgot to write it probably
Maybe they mean for what r does the sum equal a_1/(1-r)
But hard to tell
Well can i atleast know how to find the answer for a infinite sequence?
Okay okay
How do you do question 1?
hi
How to solve 1
<@&286206848099549185>
hey how do you solve the limit of (x+1)/(x-1) when x goes to 1
Start by just plugging it in. What do you get when you insert x=1?
okay what about them?
What happens as you approach 1 from the left?
it goes to negative infinity
Indeed
and otherwise to positive infinity
So then what can you say about the limit?
it doesn't exist
Easy as that
thank you,but is there a way of writing it this down
Quick question- how can you solve this type of question (calc ab)
At what points on the curve f(x)=________ is the slope equal to ____
Writing what down?
well how would I know it approaches negative infinity and positive infinity without trying different values for x
is there another way ?
@solemn juniper
Have you seen the notation $1^-$ and $1^+$ before?

