#help-0

1 messages · Page 848 of 1

indigo jetty
#

Hmm, actually there's another way to do it

vagrant flax
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ahh hmm

indigo jetty
#

notice you are given A and B, 2 points on the circle

vagrant flax
#

yep

indigo jetty
#

You are told the centre of the circle is on the x-axis

vagrant flax
#

i can find the equation of the line

indigo jetty
#

so one thing for sure is

vagrant flax
indigo jetty
#

the coordinates of the centre is (a, 0)

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yup

vagrant flax
indigo jetty
#

so what can you tell about the lines that connect A to the centre and B to the centre?

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should be doable from there

vagrant flax
#

Ohh i can find the gradient of A and centre and gradient of B and centre

indigo jetty
#

no need

alpine nacelle
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C is at the same distance from A than from B. It is true for the midpoint of AB too

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What is the line that goes through both ?

vagrant flax
#

I guess

alpine nacelle
#

l doesn't go through the center of the circle

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Perpendicular bisector of AB does

vagrant flax
vagrant flax
alpine nacelle
#

Your perpendicular bisector intersects the x-axis at the center of the circle

vagrant flax
#

let me try work it out

tacit flax
indigo jetty
#

@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

alpine nacelle
#

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

vagrant flax
vagrant flax
indigo jetty
#

yup, both methods work

vagrant flax
#

Ken G thankyou soo much too!!

indigo jetty
#

i just listed the one that came to my mind first lol

vagrant flax
#

😂

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Yall are legends

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got maths test in 2 days time !

quartz osprey
#

i have no idea how this is wrong

alpine nacelle
#

-(n-3) = -n+3

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You got tricked by the sign

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the exponent of x should be -n-3, so n+3 if you put it in the denominator

vagrant flax
quartz osprey
#

ohhh

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let me read up

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sec

vagrant flax
#

yep its n-3

quartz osprey
#

uhh i might need to redo it

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i dont really understand the problem through reading lmao

vagrant flax
#

i can show you working out if you want

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XD

quartz osprey
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sure if youre willing to lol

vagrant flax
#

Okay just a second

quartz osprey
#

lemme flip it thank you

analog vortex
#

Hello, I need a bit of help in here

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$$lim_{x\to\infty}\frac{(7-x)(3+3x)}{(3-2x)(11+7x)} = lim_{x\to\infty}\frac{21+18x-3x^2}{22-x-11x^2}$$

#

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?

lime tangle
#

hmmmm

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table of values?

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@analog vortex

lime tangle
#

or that

ocean sealBOT
glass lichen
#

$\lim_{x\to\infty}\frac{21x^{-2}+18x^{-1}-3}{22x^{-2}-x^{-1}-11}$

ocean sealBOT
glass lichen
#

leaving 3/11

analog vortex
#

pikathink that's what I tried to do... but for some reason it wasn't accepted as an answer

glass lichen
#

oh cause you messed up expanding

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$(3-2x)(11+7x)=33+21x-22x-14x^2$

ocean sealBOT
analog vortex
#

oh hahaha alright thank you wb_yunbei

glass lichen
#

so yeah, double check your expanding, then it's just read off the leading co-efficients

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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

ocean sealBOT
glass lichen
#

proof is similar to the trick of dividing by x^2, just instead use x^(degree of f and g)

small hatch
#

for what values of x is f(x) < 0?

alpine sable
#

can i get help with b

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not a

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a is 30 and i know

flint badger
#

Can you try to figure that out first?

small hatch
flint badger
#

Close, the question is basically saying: "what values of x make the result (y) < 0

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So at what point in the graph is y < 0?

small hatch
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-7, -4, -2, 10

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would 0 count?

flint badger
#

Ok @small hatch I assume its asking for an interval

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So x = -7 would give a y result < 0, yes

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but

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There's also infinitely many others

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So you actually have to give me a range

small hatch
#

the teacher put this

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for one of the previous ones

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idk if it plays a part

flint badger
#

Oh really?

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Umm

small hatch
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yeah. i dont know what it means though

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there is no explanation to it

flint badger
#

Oh wait there's dots on the graph right?

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Like points plotted along the curve?

small hatch
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yea

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the ones i listed have dots

flint badger
#

Ok I guess thats how they want you to do it

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So then yes that's right

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Just make sure to put x = -7, -4, -2, 10

small hatch
#

okay one sec

flint badger
#

Is 0 < 0

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?

small hatch
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no

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its equal to

flint badger
#

Exactly

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so you wouldn't include that

small hatch
#

if it was 0 <= 0 it would be included

flint badger
#

Yea

small hatch
#

alright

flint badger
#

Hmm

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weird how your teacher made it like that

small hatch
#

so then when it asks for greather than

flint badger
#

Normally teachers would make you give a range

small hatch
#

i make the points above the 0?

flint badger
#

So like

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Yea

small hatch
#

this is another problem she did

flint badger
#

Oh yeah thats just plotting the graph of a parabola

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Do you have any questions for that?

small hatch
#

no thats simple really

flint badger
#

I don't know why she makes you give individual points though

small hatch
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i have a question for a diff one just give me a bit to get to it

flint badger
#

because there's technically infinitely many points

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when f(x) < 0

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It's the RANGE that matters

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Like from (-8, 0), f(x) < 0

small hatch
#

yeah she teaches weirdly, not sure why

flint badger
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The "(" and ")" notation means it's not included

small hatch
#

okay how about this:

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If f(-5)=f(b) and -5 ≠ b, what is the value of b

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@flint badger if you're still available

flint badger
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I'm very confused

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Man maybe I'm just slow today

small hatch
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yeahhhh same.... 😂

flint badger
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I'm not getting this

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Is there anymore information provided?

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I really don't get what they're asking here LMAO

small hatch
#

lmfao nope. i'll send you the whole page

loud sentinel
flint badger
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OHH

loud sentinel
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Hey guys where the negative go

flint badger
#

I completely forgot you were using the graph before

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also I believe you put f(0) and not f(b)

small hatch
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oh yeah oops 💀

flint badger
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Ok basically what it's saying is that

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Well first evaluate what f(-5) actually is

thorn sundial
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do you guys know this?

small hatch
flint badger
#

Because you can evaluate that right

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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?"

small hatch
#

correct

flint badger
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So what is f(-5)

small hatch
#

0?

flint badger
#

Not quite

small hatch
#

it doesnt have a point on the graph

flint badger
#

If you put -5 for x into the graph

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What corresponding y value would you get

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Imagine it's (-5, y)

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Try to figure out what y is

small hatch
#

it looks like -4?

flint badger
#

Yeah exactly

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The point would be (-5, -4)

small hatch
#

how though?

flint badger
#

So now you know what f(-5) is right

small hatch
#

the point isnt marked

flint badger
#

It doesn't have to be

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Don't let the other question throw you off

small hatch
#

okay

flint badger
#

In the other question the points did matter

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Because she was asking which points were below 0

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And she was asking for the x value of those points lol

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So you know f(-5) = -4

small hatch
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okay understood

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yes

flint badger
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so if f(-5) = -4, and f(-5) = f(b)

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What is f(b)?

woven river
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egg dog when you get a chance could you help me?

flint badger
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Yeah sure

woven river
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okay i just need help evaluating a few questions

small hatch
#

f(b) = -4

woven river
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when you’re finished

flint badger
#

Yeah so what other point in the graph do you get -4

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And I shouldnt say point

small hatch
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-4?

flint badger
#

But for what other x value (in this case it's b) do you get -4

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Exactly

small hatch
#

so the value of b is -4

flint badger
#

Both f(-4) and f(-5) give you -4

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Correct

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Does it make sense?

small hatch
#

sort of

flint badger
#

What are you confused about

small hatch
#

let me check

flint badger
#

b and x are just the values you plug into the function

small hatch
#

again

flint badger
#

f(x) or f(b) is the corresponding y value

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I can help you @woven river

woven river
#

great okay

flint badger
#

,rotate

woven river
#

.rotate

ocean sealBOT
woven river
#

whooos

flint badger
#

It's ok

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Alright so what do you think g(3) means in this sense?

woven river
#

um is ir okay if we do a few

flint badger
#

Yeah

woven river
#

i think i have 2 other questions okay

flint badger
#

Yeah we'll get to those, so just think about what g(3) means

woven river
#

(3) would go where x is correct?

flint badger
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Yes so

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every function has a name ok,

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this one is called g

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and it takes in an input, x

woven river
#

ok

flint badger
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so the function would be written as g(x)

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= whatever

woven river
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yup

flint badger
#

So it says if I put in an input of 3, what will I get

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In other words, if I set x = 3, what do I get

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So yes, you're replacing x with 3

woven river
#

alright yeah i understand so far

flint badger
#

So just plug in 3 for x, and then evaluate it

woven river
#

would i keep the parentheses

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?

flint badger
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wdym

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$g\left(3\right)=2\sqrt{4\left(2\right)-3}+3$

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Should look something like this

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Oops not 2, I meant 3

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bruh

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wait

woven river
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lol

flint badger
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$g\left(3\right)=2\sqrt{4\left(3\right)-3}+3$

ocean sealBOT
#

eggdog

flint badger
#

You're still evaluating g(3) right

woven river
#

yeah that’s what i was staying to say

flint badger
#

You're not done

woven river
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okay

flint badger
#

And whenever you plug in a value for a variable

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You should put parantheses

dusk tiger
#

Egg how are you still going at this 😂

woven river
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he’s been doing this for a while

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?

flint badger
#

I take breaks lol

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Of course I do, I have my own work

woven river
#

egg are you still in hs?

chilly spruce
#

Which equation represents the line that passes through the point (1,5) and has a slope of −2?

flint badger
#

Yeah

dusk tiger
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Yeah he helped me at 10 this morning and it’s now 8

flint badger
#

@chilly spruce Hold on this channel is occupied

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Try asking it somewhere else, but dont spam every channel

chilly spruce
#

ok sorry

flint badger
#

Its ok

#

@woven river Let me know when you're done evaluating it

woven river
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basically plugging in 3 right?

flint badger
#

Yeah

woven river
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yup done

flint badger
#

Now work it out

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You have everything you need to work it out

woven river
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okay should i come back with my answer?

flint badger
#

Yeah

woven river
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alright

small hatch
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hey eggdog

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there is another similar question i just want to make sure im right

flint badger
#

Sure

small hatch
#

b = 3.5 ?

woven river
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i’m sorry egg what would 4(3) be?

flint badger
#

its the same as 4(3)

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4 * 3

woven river
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oh okay

dusk tiger
#

Wouldn’t it just be 0 since it’s halfway

tardy plank
#

how do I find where this is continuous?

flint badger
woven river
#

would it be 6?

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oh i’m sorry

buoyant edge
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@tardy plank sin is continuous everywhere,

small hatch
flint badger
#

No that would be

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g(-8)

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Wouldn't it

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At -6, y = 2

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So where else is y = 2

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or in this case, g(b)

flint badger
#

Could you take a picture of your work

tardy plank
#

@buoyant edge how would you use algebra to prove that in this case though so I can figure out other similar problems

woven river
#

well i do have a question

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what is the bar on top of the numbers called again

flint badger
#

$\sqrt{ }$

ocean sealBOT
#

eggdog

flint badger
#

you mean this?

woven river
#

yeah

flint badger
#

That is a square root

woven river
#

okay i forgot

flint badger
#

@woven river I would suggest first knowing what these operations are before tackling these problems

woven river
#

let me redo this

small hatch
#

how would y = 2 at -6? wouldnt it be at -5?

flint badger
#

Do you know what a square root means?

buoyant edge
#

@tardy plank look up proof that sin is continuous; you need epsilon-delta definition for that

woven river
flint badger
#

I misread the graph

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smh im sorry

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you're absolutely right

small hatch
#

youre fine

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haha

flint badger
#

At what other x is y = 2

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ok good

small hatch
#

none

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wait do you mean 3 again

flint badger
#

no I would say at g(4) its pretty close to 2

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OH MY GOD

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im actually stupid

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ok you know what

small hatch
#

what happened 😂

flint badger
#

3.5 would be a good guess yeah

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I don't know man I thought it was still 2

small hatch
#

haha

flint badger
#

g(3.5) would be close to 3 yes

sick torrent
#

I will pay someone 50 cents to do my homework for me

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Take it or leave it

small hatch
#

okay, thank you!

flint badger
#

1.5 would also work @small hatch

maiden saffron
#

HELP

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Emerge by

flint badger
#

oh as well as -9, they'res a bunch of points before it

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that still give you an output of 3

small hatch
#

oh

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i see

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it asks for one tho

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so any works

flint badger
#

An exact one would be best

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Meaning an integer

woven river
#

egg dog would it be 4 square root 3

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like the operation

small hatch
#

-9 has a point, does it matter?

flint badger
#

I guess you should use that then

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As you did for the f(x) < 0

flint badger
small hatch
#

okay

flint badger
#

$g\left(3\right)=2\sqrt{4\left(3\right)-3}+3$

ocean sealBOT
#

eggdog

flint badger
#

If you evaluate this properly, you should get g(3) = 9

small hatch
#

thank you so much eggdog! great pfp btw

flint badger
#

Which means that if we were to graph this, an x value of 3 would give us 9 as the output

flint badger
small hatch
#

what grade r u in btw? you said youre still in hs

flint badger
#

Im a sophomore

small hatch
#

oh damn.. what math classes u taking!?

flint badger
#

Calculus II atm

small hatch
#

wtf youre actually crazy smart

flint badger
#

Nah nah lmao

small hatch
#

yesss whaat... i take pre calc next year (junior year)

flint badger
#

@woven river Sorry I have to leave right now

woven river
#

this is how

flint badger
#

You forgot about the -3 + 3 part

small hatch
#

cya!

flint badger
#

4(3) = 4 * 3 but there's still the -3 inside of the square root and the +3 on the outside

flint badger
woven river
#

oh shoot

flint badger
#

See if someone else can help you, I have to eat dinner

woven river
#

and cya

#

okay

flint badger
#

Bye :/

buoyant kayak
woven river
#

isn’t 4(3) times

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like 4 time 3 = 12

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-3 9

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+3 12

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right

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@buoyant kayak

buoyant kayak
#

the +3 is on the outside of the root, right?

woven river
#

yes

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i’m sorry what does that mean

buoyant kayak
#

well you can't just bring a number from outside the root inside the root

woven river
#

wait would i bring that down

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so 12 + 3

buoyant kayak
#

?

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where are you getting 12

woven river
#

i don’t know anymore then

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then it would be 9

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i’m sorry right

buoyant kayak
#

yes, 9 is under the square root

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and what is the square root of 9

woven river
#

3

buoyant kayak
#

so now you have 2(3)+3, right?

woven river
#

yes

buoyant kayak
#

and what is that?

woven river
#

9

buoyant kayak
#

right

woven river
#

is that all

#

my answer is 9?

buoyant kayak
#

i'm not sure what your question is

woven river
#

okay let me post

buoyant kayak
#

alrighty

woven river
#

,rotate

ocean sealBOT
buoyant kayak
#

ah, then yes

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your answer is 9

woven river
#

oh okay could we do my other question?

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i just have 2 more

buoyant kayak
#

sure

woven river
#

let me get them

radiant bronze
#

At which points tangent line to f(x) = 1/(x2 – 25) is horizontal and at which points is it vertical?

woven river
buoyant kayak
#

so plug in 1 for x

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evaluate the root

woven river
#

yup got that

buoyant kayak
#

then order of operations

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what did you get?

woven river
#

let me do the math lol sorry

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would it be 1

buoyant kayak
#

the root?

woven river
#

yes

buoyant kayak
#

yes

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and what is the square root of 1?

woven river
#

1

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lol

buoyant kayak
#

right

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so now you have 2(1)+3

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and what is that?

woven river
#

4

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im sorry 5

buoyant kayak
#

right

woven river
#

makes so much sense

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lost one um

buoyant kayak
#

so what's 3(-1)?

woven river
#

2

buoyant kayak
#

?

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$3\times -1$

ocean sealBOT
#

a disappointing son

woven river
#

oh jeez

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-3

buoyant kayak
#

right

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and now $4\times (-1)^2$

ocean sealBOT
#

a disappointing son

woven river
#

sorry internet uh 16?

buoyant kayak
#

remember your order of operations

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parenthesis, exponents, multiplication and division, addition and subtraction

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which one comes up first?

woven river
#

ok i’m

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multiplication

buoyant kayak
#

i meant in the order that i posted

woven river
#

parenthesis

buoyant kayak
#

right

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and do you see anything that has to be done in the parenthesis?

woven river
#

yeah

buoyant kayak
#

does the -1 need to be changed?

woven river
#

yes

buoyant kayak
#

anything happening to that in the parenthesis?

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are you sure?

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it's just the -1 in parenthesis there

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nothing else is with it

woven river
#

then no

buoyant kayak
#

right

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now move on to the next one

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which is...?

woven river
#

exponents

buoyant kayak
#

see any exponents?

woven river
#

yes

buoyant kayak
#

so can you evaluate that?

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(-1)^2?

woven river
#

yes

buoyant kayak
#

what is it?

woven river
#

jeez

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-1?

buoyant kayak
#

we can rewrite $(-1)^2$ as $(-1)(-1)$

ocean sealBOT
#

a disappointing son

woven river
#

yup

buoyant kayak
#

what happens when we multiply a negative by a negative?

woven river
#

positive

buoyant kayak
#

so what is (-1)^2?

woven river
#

1

buoyant kayak
#

right

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now multiply it by 4

flint badger
#

This is crazy @buoyant kayak now that I just realized what your pfp was I cant unsee it

woven river
#

4

buoyant kayak
#

correct, so now you have -3+4-5

flint badger
#

I dont know how but i didnt notice it at first, anyways sorry to interrupt

buoyant kayak
#

now you can just add and subtract from left to right

#

egg i'm not sure what you mean lol

woven river
#

yeah

buoyant kayak
#

my pfp is my friend from high school

flint badger
#

I didnt notice it was a face rotated 90 degrees counter clockwise

woven river
#

-4

buoyant kayak
#

oh

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lol

buoyant kayak
mossy stirrup
#

how do i do this with steps?

placid zinc
#

That means for every billion parts you take, 8 of them are lead

woven river
#

@buoyant kayak i have one more

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if that’s fine

buoyant kayak
#

sure

woven river
#

one moment

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it’s find the intersection between the filling functions algebraically

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a tad blurry

#

sorry

buoyant kayak
#

,rotate

ocean sealBOT
woven river
#

i do not the POI

#

Im just unsure how to find it algebraically

buoyant kayak
#

alright, so you want to know when these functions equal each other

woven river
#

ok

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im sorry

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was it my turn to talk or

buoyant kayak
#

yeah you're good

woven river
#

um was it when these functions equal one another

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i’m lost on that

mental hearth
#

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

buoyant kayak
#

so if you want when these functions equal to each other, what do you reckon you should do?

woven river
#

find x

#

?

mental hearth
#

you would do -5x +2. = 2x -5 but you should undrstand why

#

then solve for x

buoyant kayak
#

best to not tell the answers

#

rather let them figure it out

vestal aspen
#

Hey

mental hearth
#

k

woven river
#

still lost

vestal aspen
#

Can someone help me

mental hearth
#

op im next for help when im done u can put question

vestal aspen
#

Ok

mental hearth
#

you'd call this systems of equation right

woven river
#

yeah

mental hearth
#

generally there are 3 solutions to it

#

infinite solutions
one solution
or no solution

#

can you guess when there would be infinite solutions

woven river
#

yeah

mental hearth
#

when

woven river
#

i take that back

#

my apologies

mental hearth
#

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

woven river
#

yeah i think i understand

#

but for this problem it’s only one solution

mental hearth
#

yea it is one solution

#

do you know when it'd be no solution

woven river
#

i don’t i’m sorry

mental hearth
#

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

woven river
#

oh

mental hearth
#

because from 7 and - 3 they would go up or down the same amount and never touch

woven river
#

i understand that

mental hearth
#

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

woven river
#

yup

#

so would i have to find f

#

first

#

then plug that into g

#

sorry if all over the place

mental hearth
#

you'd find x

woven river
#

yes

mental hearth
#

f and g are two functions

woven river
#

i meant x im sorry

mental hearth
#

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

woven river
#

could u run this down step by step

#

im so tried sorry

mental hearth
#

ur good

woven river
#

i’ve gotten through ap psych and remember i had alg 2

mental hearth
#

dang u cna do ap psych but not thisl ol

#

ur good

woven river
#

yeah i guess lmao

mental hearth
#

call ap psych ap quizlet

woven river
#

seriously tho

#

lmao

vestal aspen
#

can someone help

mental hearth
#

chill

#

ok so the first step is set them equal to each other

#

-5x +2. = 2x -5

woven river
#

alright i have it

mental hearth
#

what'd u get for x

woven river
#

one moment

wanton beacon
#

Very quick question, how can I explain that I know two ratios are equivalent?

mental hearth
#

if you simply both they are the same numerical value

#

ex 3/4 6/8 both simplify to 0.75

#

idk if thats satisfactory

woven river
#

okay um 1?

mental hearth
#

yea

#

and plug that into f or g

#

and you have the location of the intersection

#

ur done

woven river
#

1,-3?

mental hearth
#

ye

woven river
#

wow

#

that ez

#

well not really

#

thanks so much mam

#

man

mental hearth
#

np

ivory gulch
#

looks like you guys are finishing up, i dont want to interrupt so just lmk when you're done

woven river
#

we’re done

#

what math do u take?

ivory gulch
#

lol

#

nvm

#

its all good

mental hearth
#

calc ii

woven river
#

you’re senior?

mental hearth
#

nah college freshman

woven river
#

oh

vestal aspen
#

bro someone help me

mental hearth
#

i took bc but school doesnt take credit

#

so im retaking 2 but i forgot everything

woven river
#

yeah i have a kid in my class ima sophomore and he takes ap clad

#

calc

#

it’s nuts

#

like how the hell

mental hearth
#

at my school ppl took it freshman year 💀

#

but its a magnet so it makes sense

#

i took it junior

woven river
#

yeah i go school for law

#

i behind i guess

vestal aspen
#

👍

mental hearth
#

nah ur good

woven river
#

all my friends take pre clac

mental hearth
#

u can try to skip/catch up over the summer

woven river
#

but then i’m taking 3 aps so it’s killing me

mental hearth
#

op how hard is ur question

woven river
#

i def will

vestal aspen
gray reef
#

Huh

mental hearth
#

bruh

#

you could do that in like a min

#

dont u just use f=ma

vestal aspen
#

Ik I just forgot

mental hearth
#

thats more of a physics thing

#

than math

vestal aspen
#

I forgot the formula

mental hearth
#

use f= ma

vestal aspen
#

Yeah it is physics

#

Thanks

mental hearth
#

F= MA is the most important physics formula bro

#

nah u gotta be taking physics 0

#

jk

#

physics is gonna get real later on

vestal aspen
#

This is my first year doing physics

mental hearth
#

what'd u get

vestal aspen
#

I’ll do it rn

#

21.78

mental hearth
#

ye u got it

#

if the mass is in kg its correct

vestal aspen
#

Alright

#

It is

mental hearth
#

ur good then

dry echo
#

Can someone help me?

mental hearth
#

how hard

dry echo
#

This is my work

#

Where am I going wrong? is my equation even correct?

mental hearth
#

we went from basic arithmetic and algebra to calc 😭

dry echo
#

RIP

mental hearth
#

i came here for calc help too cuz i havent done it in a min

raw shard
#

related rates problems are so hard lol

mental hearth
#

annoYing

raw shard
#

i can try to help

#

probably won’t be of much help though lol

#

anyways give me a minute

dry echo
#

Better than nothing man

#

ok thank u!

atomic lodge
#

Can anyone help me with question 20

#

I think it’s false

#

But I am not sure

dry echo
#

Try to graph it

raw shard
#

i don’t see anything wrong so idk

#

maybe go though it again and pay a lot of attention?

mental hearth
#

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

dry echo
#

so it is correct then

raw shard
#

@mental hearth sounds right

dry echo
raw shard
#

yes

dry echo
raw shard
#

go through it again and pay a lot of attention maybe

#

i’m not very good at these either

dry echo
#

oof

#

thank you for your time though

raw shard
#

no problem

#

hopefully you get an answer eventually

mental hearth
#

its vertex form ibut idk how i should do

raw shard
#

@dry echo wait i have a stupid idea but i’ll try anyways

dry echo
#

I have one try left

mental hearth
#

<@&286206848099549185> i helped two ppl and im down bad 🥺

dry echo
#

so I should make sure it is the correct one lol

#

We only get 3 tries

mental hearth
#

need help w this

raw shard
#

oh ok

dry echo
#

man, how am I gonna pass calc 1

raw shard
#

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

dry echo
#

isn't that what I'm supposed to do? since the formula uses radius

raw shard
#

idk it was just an idea

dry echo
#

oh I think you might be right

#

maybe I need to multiply my answer by 2

raw shard
#

no way lol

#

big brain moment if i’m right

dry echo
#

actually scared to plug it in tho

raw shard
#

i don’t blame you

dry echo
#

ok so now the question is

#

do I plug the negative

#

or the positive since the question already asks for decreasing?

mental hearth
#

nah im gonna take an L on this hw there are 11 more 😭

raw shard
#

i’m trying to differentiate it, just a minute

wind pagoda
tropic dagger
#

can someone walk me through how to convert y = ax2 + bx + c to vertex form symbolically (just with variables, no actual values?)

dry echo
mental hearth
#

nah its not

dry echo
#

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

wooden sorrel
#

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

buoyant edge
#

It's legit.

wooden sorrel
#

kool

buoyant edge
#

You're just applying spherical symmetry to 1/2 a sphere 🙂

wooden sorrel
#

guess so

raw shard
#

@dry echo bruh

#

idk how it’s not negative

#

oh wait

wooden sorrel
#

should have been tipped off when the question said the surface area was decreasing at a positive rate prolly

dry echo
raw shard
#

it says the rate at which it decreases

dry echo
#

Yeah

raw shard
#

well i almost got it right lol

dry echo
#

Either way, I'm glad I found the correct way to solve this

#

WIth your help @raw shard

#

thank you!

raw shard
#

looks like i don’t completely suck at these problems lol

#

no problem

dry echo
#

yeah not as much as I do lol

#

Although it was introduced to us today

raw shard
#

yeah that was hard for me too

#

way too many chain rules right there

#

implicit differentiation and normal chain rule in one

dry echo
#

yeah lol

buoyant edge
#

What made you think the first limit is 21?

craggy niche
#

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.

buoyant edge
#

Well let's start from the top

lilac kiln
#

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)?

buoyant edge
#

Channel is occupied.

craggy niche
#

lim x --> -1^-

#

That means x is being approached from a upwards angle, is it not?

#
  • means approaching from below afaik
buoyant edge
#

"downward angle"? it just means that we're approaching -1 from the left

#

So our test values are getting bigger

craggy niche
#

yeah my bad, I mean to say that we're traveling upwards as the values increase due to the slope of the line

craggy niche
buoyant edge
#

Yes, that's a jump discontinuity

craggy niche
#

I see

buoyant edge
#

So the limit will not exist there.

craggy niche
#

Does that mean the answer to the question is DNE?

buoyant edge
#

Not to the first one

craggy niche
#

ok, so it is.

#

Oh

buoyant edge
#

Because the jump isn't at -1

#

it's at 1

craggy niche
#

I'm so dumb, you're right

buoyant edge
#

Not dumb.

#

You rushed a little bit, that's all.

#

Let's get back to the question

craggy niche
#

At -1 you will be approaching 1 from a value greater than 1, from what I understand.

buoyant edge
#

Yes.

craggy niche
#

How would I note that as an answer though? x>1 ?

buoyant edge
#

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

craggy niche
#

Alright, the first 3 answers in that case are 1, with #4 being "2"

#

F(-1) = 2

buoyant edge
#

Yes.

#

Since it approaches 1 as x approaches -1 from the left and from the right, the limit exists.

#

and is 1.

craggy niche
#

Understood

buoyant edge
#

However, as you can see, at x = -1, F(x) = 2

#

That is called a hole.

craggy niche
#

Duly noted

#

In the hole a limit = DNE

#

correct?

buoyant edge
#

You're asking if there is a hole at the limit, then the limit does not exist?

craggy niche
#

This is my progression so far btw ^

buoyant edge
#

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?

craggy niche
#

Yessir

buoyant edge
#

Great.

#

Alright, now for $\lim_{x \to 1^+}$

ocean sealBOT
#

Chris24

craggy niche
#

Am i to click the right answer as a reaction?

buoyant edge
#

No no no those are latex things lol

#

I was just trying to be clear

craggy niche
#

Ah my bad, yeah

buoyant edge
#

Look at the graph: as we approach 1 from the right, where is the function going?

craggy niche
#

towards y=4

buoyant edge
#

Nice.

craggy niche
#

Cheers mate, i've finished the question

#

I'm just going to take some notes of what you've written

buoyant edge
#

Nice job!

craggy niche
#

May I post more afterwards or is there a limit?

buoyant edge
#

As much as you want! Just try to be courteous to others (i.e. don't interrupt channels when others are working together).

craggy niche
#

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

buoyant edge
#

It's not that strict: if it looks free, it probably is. If it's not, someone will let you know.

craggy niche
#

Alright, i'll post them here

buoyant edge
#

Sounds good.

craggy niche
#

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?

buoyant edge
#

Those braces define a piecewise function

craggy niche
#

I understand that x-> 4- is -12, 4+ is 5, but what is the third (x->4)

buoyant edge
#

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

craggy niche
#

I see, so in this case it's about the function producing two differing graphs which cannot meet at one point where x=4

buoyant edge
#

Yeah, that's the idea

craggy niche
#

That was much easier than I thought, for it being something I was unfamiliar with...

buoyant edge
#

Since the limit is not the same from both sides, it does not exist

craggy niche
#

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?

raw shard
#

there’s no limit there

#

it’s just f(1)

craggy niche
#

The software notes that f(1) = -3 is a correct answer

raw shard
#

it is

craggy niche
#

But why was it -3 over -1?

raw shard
#

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

craggy niche
#

I see

raw shard
#

remember this says nothing about a limit, just what f(1) is

craggy niche
#

The hole means that it doesn't count as a limit and the solid circle should be the one noted as the answer?

raw shard
#

yes

craggy niche
#

Understood, i appreciate it

raw shard
#

no problem

craggy niche
#

This seems more confusing due to the -INF values. What does it mean by continuity on (-INF, INF)?

raw shard
#

@craggy niche pretty sure it means it’s continuous everywhere

craggy niche
#

How would one note that as an answer though?

raw shard
#

what exactly do you mean

craggy niche
#

I don't understand what you mean by that, and how i would note that as an answer on my quiz :/

raw shard
#

it means it is defined everywhere

#

no holes

craggy niche
#

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

raw shard
#

basically what value of c makes 16-c = 4c+5

mellow wren
#

Excuse me

raw shard
#

what

mellow wren
#

I need a bit of help with inequalities

raw shard
#

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

mellow wren
#

Alr I tried getting help in 8

#

But nobody will help

craggy niche
#

That was correct. You found that by equating the two functions to themselves, right?

raw shard
#

yeah

#

at x = 4

craggy niche
#

ok, i've written it down as a note. Thank you

raw shard
#

no problem

tardy basin
#

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)

raw shard
#

my guess is yes

#

looks right

tardy basin
#

Or like 1 - ((72/73)*(430/436))?

tardy basin
#

Confusing myself 😂

raw shard
#

i just put it in math terms as i read it and got what you first sent

tardy basin
#

Ok gotcha, but when do you do the 1 - (...) ?

raw shard
#

sorry i don’t know, what you sent just looked right to me so i said yes

tardy basin
#

Oh no worries coolguy

alpine sable
#

yooo

#

its dobbs

#

why do i recognize you?

tardy basin
#

youtube prob :p

alpine sable
#

most likely

#

i think remember seeing you a long time ago back when i was into pokemon

alpine sable
#

i mean im no genius at math

#

i see things if they work then they work

#

and this just kinda seems to work

pastel pelican
#

sorry isn't your discussion over? if its not i can delete my post

alpine sable
#

can't see why you can't keep it up

tardy basin
#

Oh go ahead Payrim!

#

Maybe repost it so its the newest message

pastel pelican
#

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

karmic quail
#

“write cos x in terms of tan x” it gives the pythagorean identity, then the next step is to “take reciprocals”.. how come?

pastel pelican
rich basin
#

could anybody please help me, been waiting for 1 hour in question 1

serene stream
#

can someone just tell me what n means in this case?

#

i am very much a beginner

#

I am learning sets right now

wary badge
#

Could someone please help me on providing this identify

raw shard
#

@alpine sable only one of those fractions can be simplified

#

you don’t see it?

chrome notch
#

How do you explain this?

hardy gulch
chrome notch
#

You only have to explain how to solve an infinite geometric sequence

#

You don't have to solve it

noble sinew
#

“If the r in the formula…”

#

If what with the r?

gray isle
#

there are probably parts
i)
ii)
conveniently cut off

chrome notch
#

Yeah that's my problem like how do we find r

#

If its infinite

fallow pagoda
#

any even number so 22/100 can be

noble sinew
chrome notch
#

Wait

noble sinew
#

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

chrome notch
#

Well can i atleast know how to find the answer for a infinite sequence?

noble sinew
#

It gives you the result right there

#

It is equal to a_1/(1-r) when |r|<1

alpine sable
#

Hi

chrome notch
#

Okay okay

alpine sable
#

How do you do question 1?

fast oak
#

Hello

crystal raft
#

hi

fast oak
#

How to solve 1

marble saffron
#

hey how do you solve the limit of (x+1)/(x-1) when x goes to 1

solemn juniper
#

Start by just plugging it in. What do you get when you insert x=1?

marble saffron
#

well it divides by 0

#

2\0

#

@solemn juniper

solemn juniper
#

Ok, good

#

Now examine the left- and right-hand limits separately

marble saffron
#

okay what about them?

solemn juniper
#

What happens as you approach 1 from the left?

marble saffron
#

it goes to negative infinity

solemn juniper
#

Indeed

marble saffron
#

and otherwise to positive infinity

solemn juniper
#

So then what can you say about the limit?

marble saffron
#

it doesn't exist

solemn juniper
#

Easy as that

marble saffron
#

thank you,but is there a way of writing it this down

waxen spruce
#

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 ____

solemn juniper
#

Writing what down?

marble saffron
#

well how would I know it approaches negative infinity and positive infinity without trying different values for x

#

is there another way ?

#

@solemn juniper

solemn juniper
#

Have you seen the notation $1^-$ and $1^+$ before?