#help-0

1 messages · Page 646 of 1

wheat prawn
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great

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get it xd

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corny joke lol

alpine sable
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what is wrong here

vale wigeon
#

what are the drop-down options for point A?

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and most importantly, why does it have two contour lines passing through?

vale wigeon
#

hm.

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there's honestly no telling what's going on at A

alpine sable
#

what really?

vale wigeon
#

i would put 'not a critical point' but im honestly not sure

alpine sable
#

ok

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so B,C,D are correct?

whole maple
#

Can anybody tell me the formula to find the truing point (linear equations)

vale wigeon
vale wigeon
whole maple
#

Oh idk

vale wigeon
#

??

whole maple
#

I just needed like a formula

vale wigeon
#

a formula for what

whole maple
#

Like this for example

vale wigeon
#

do you know calculus?

whole maple
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No I’m in year 8

vale wigeon
#

okay then you'll need the special case for parabolas

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for y = Ax^2 + Bx + C, the turning point occurs at x = -B/(2A)

whole maple
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Oh ok

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Ty

sullen pagoda
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Does anybody know how to make a graph from this?

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im very lost

snow roost
paper maple
wild leaf
paper maple
#

((-b + d )/ 2a + (-b - d) / 2a )/2 right? @vale wigeon d = sqrt(b^2-4ac)

vale wigeon
#

yes...

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this simplifies to -b/(2a).

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(-b + d) + (-b - d) = -2b, after all.

paper maple
#

ahh, I realise my mistake

pallid ferry
#

can i get some help with this problem im not sure if im doing it right

#

so far i have csc(2θ)=-2 and csc(2θ)=-3 but im not sure if its right or what to do next

stable pecan
#

Do you know the general solution for the equation sin(theta)=sin(alpha)?

last dome
#

not really math but do anyone know these 2?

stable pecan
#

This channel is occupied

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@last dome post somewhere else

pallid ferry
#

no i dont think i know about sin(theta)=sin(alpha)

stable pecan
#

It's alright, try to convert this csc(2θ)=-2 into this form sinx=siny, then we will proceed from there

pallid ferry
#

alright give me a second to figure it out

alpine sable
#

got it after a few guesses

wild stump
#

what is $$d^3x/d^3y$$

ocean sealBOT
#

toadmilk

wild stump
#

what does it represent

ionic jewel
stable pecan
#

this channel is occupied

ionic jewel
#

looks like it was meant to be third derivative

wild stump
#

oh sorry I thought it was done

ionic jewel
#

ah sorry alacris

pallid ferry
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is this right?

stable pecan
#

this one is for csc(2θ)=-2?

pallid ferry
#

yes

vale wigeon
#

looks a little sus to me

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do you have work to show?

stable pecan
#

My answer is npi/2+ (-1)^n pi/12

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How did you reach your answer @pallid ferry ?

pallid ferry
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i wasnt quite sure what to do with the 2 and then i was looking at a similar problem in my text book and i tried to do the same thing so im not really sure

stable pecan
#

Can you show your steps please?

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You need to treat the 2theta as you normally treat a single theta. Then divide by 2 at the very last step

pallid ferry
stable pecan
#

How's sin(2theta) = -2?

pallid ferry
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i meant to put csc(2theta)

stable pecan
#

Try again then

pallid ferry
#

alright give me a second

vale wigeon
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uh

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sin(2pi) is not 2???

pallid ferry
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yeah i wrote it wrong

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i got this now

stable pecan
#

I told them to convert it to sine form

vale wigeon
#

sin(2pi) is still not 2

stable pecan
#

It's out of range

stable pecan
pallid ferry
#

that sin is meant to be csc

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i keep mis writing

stable pecan
#

You need to convert the cosec into sine

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It's 1/sin(2theta)

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Now try again

pallid ferry
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i dont know what to do with that my text book doesnt have any examples like that

stable pecan
#

Convert the cosec into sine, then proceed

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You know that cosecx=1/sinx, right?

pallid ferry
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yes i just dont know what to do with 1/sinx

snow roost
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@stable pecan can you help me

stable pecan
pallid ferry
#

ohh i see now

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let me try it again real quick

stable pecan
pallid ferry
stable pecan
#

If sin x= sin y, then you can write x = nπ + (-1)^n y, If y ∈ [-π/2, π/2]

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7π/6 doesn't belong in the interval [-π/2, π/2]

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rewrite sin(7π/6) so that the angle inside sine belongs to the above interval

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Otherwise correct

pallid ferry
#

should it be pi/6 then?

stable pecan
#

yes

pallid ferry
#

what is the part about the y

knotty sleet
#

If you already have sin2theta =-1/2 you can just immediately find values for 2theta

stable pecan
#

yes

knotty sleet
#

Writing it as -sin(pi/6) complicates things😅

stable pecan
#

But we need to find the general solution

pallid ferry
#

oh so the pi/6 is equal to y?

stable pecan
pallid ferry
#

at the beginning

stable pecan
#

Sorry, I missed the lack of negative sign there

stable pecan
pallid ferry
#

yes

stable pecan
snow roost
stable pecan
#

Do you want to know why y has to belong in the interval [-π/2, π/2]?

tired geyser
#

Sketch the triangle with corners in (1, 1), (2, 1) and (1, 3) and parameterize its edge so that the points
are completed in the specified order.

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can someone give the solution to this

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would help a brother out

pallid ferry
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im confused about when you said sinx=siny and im also a little confused about the y in the interval

craggy dirge
#

how would i do this?

jagged imp
#

wow 3 different questions in the space of a minute in one channel

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im impressed

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maybe use another one

tired geyser
#

need help man xD

#

?

stable pecan
#

This channel is occupied

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Post somewhere else

stable pecan
tired geyser
#

can u help me

stable pecan
#

Please post in another channe;

pallid ferry
#

ok i think i get it

#

do i have to do this again for the other part of the equation?

stable pecan
#

you will need to rewrite sin(7π/6) so that the angle inside sine belongs to the interval [-pi/2,pi/2]

honest umbra
#

how can I find x so that 2x, 3x+1 and (x^2)+2 r the first 3 terms of an arithmetic sequence

boreal prawn
#

how many three digit numbers in base 9 have the property that each digit increases by 1 when the number is converted to base 8?

jagged imp
#

wow is that 4 different questions ontop of the already ongoing one in like 10 minutes?

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I'm impressed

pallid ferry
#

is this better

boreal prawn
#

sorry

stable pecan
#

It's correct

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I hope you can do csc(2θ)=-3 on your own now?

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It's similar

pallid ferry
#

yeah i think i can do that

stable pecan
#

wait

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there should be a - sign in front of pi/12

pallid ferry
#

oh yeah

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so the other problem should be the same thing then right

stable pecan
#

yes

pallid ferry
#

alright thanks

alpine sable
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wdym solve

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theres nothing to solve for

vale wigeon
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it says "simplify", polla

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@alpine sable this is a matter of careful exponent manipulation

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perhaps it'll help to rewrite all roots as fractional exponents

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maybe even make a temporary substitution like x := sqrt(a) to make your own life a little easier

alpine sable
#

just do what Ann says rewrite them

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so it's just makes your life easier

pastel jasper
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Instead of = wouldn't it be more correct if it was an arrow ->

vale wigeon
#

no

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you are already writing "lim"

pastel jasper
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oh

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but it means f(x)->1 right

vale wigeon
#

if you want, you can write ``$f(x) \to 1$ as $x \to 2$''

ocean sealBOT
pastel jasper
#

oh

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thanks!

hot osprey
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how do i find the exact value of cos (-19pi/6)

heady helm
#

Student desmos scientific calculator on google

hot osprey
#

yeah i meant showing work and stuff

vale wigeon
#

add a suitable integer multiple of 2pi to the angle so that it falls between 0 and 2pi

hot osprey
#

yes done that, got 5pi/6

vale wigeon
#

then look at the unit circle

hot osprey
#

but i am not sure

#

if like

#

the quadrant i picked is right

vale wigeon
#

that is correct, 5pi/6 is exactly what you should be getting.

hot osprey
#

does converting it to degree help?

vale wigeon
#

if it helps you then yes

hot osprey
#

so that's 210 degrees

vale wigeon
#

no

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5pi/6 is not 210°

hot osprey
#

wait whoos

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150

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2nd quadrant right

vale wigeon
#

yes

hot osprey
#

then since cos of pi/6 is

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radical 3/2

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it would be 5 rad 3/2?

vale wigeon
#

you meant sqrt(3)/2

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and no, cos(5x) is not 5cos(x)

hot osprey
#

oh yeah, sorry about my english

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oh wait

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uni circle chart

vale wigeon
#

unit

hot osprey
#

t

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sorry lol did it bother ya xD

ocean sealBOT
#

Πολλά άτομα είναι

#

Πολλά άτομα είναι

jagged imp
#

good so far

#

although equals suffices over the implies arrow here

ocean sealBOT
#

Πολλά άτομα είναι

jagged imp
#

whatever

#

equals is best anyways imo

alpine sable
#

up to you ¯_(ツ)_/¯

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I use arrows

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So what do I do

#

now

jagged imp
#

you want the sqrt to have an 18 under it instead of a 2

alpine sable
#

yeah

jagged imp
#

so find that sqrt(9) in 36 that makes the sqrt into sqrt(18)

sacred vigil
ocean sealBOT
#

Πολλά άτομα είναι

jagged imp
#

well thats 6, not 36.

alpine sable
#

Well that's root 36

sacred vigil
#

Wait

#

May I give the exact answer

jagged imp
#

36=12*3=12*sqrt(9)

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was the point i was getting at

alpine sable
#

oh right ok I didn't get it at first

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alright

jagged imp
#

yeah no worries i was having trouble wording it in an easily parsable way in the first place

ocean sealBOT
#

Πολλά άτομα είναι

jagged imp
#

ye

ocean sealBOT
#

Πολλά άτομα είναι

jagged imp
#

yes.

ocean sealBOT
#

Akhandanand Tripathi

alpine sable
#

k cool cheers

jagged imp
#

nw mate

sacred vigil
#

It was easy, why were you stuck?

#

??

jagged imp
#

easy is relative

sacred vigil
cyan saddle
#

What happens to the slope if you take the reciprocal of a function?

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Assuming, it isn't 0

alpine sable
jagged imp
#

if you're talking about the derivative of the reciprocal, you'd have to consult the chain rule

cyan saddle
#

Any function

jagged imp
#

Well if the derivative of f(x) is f'(x), chain rule tells us that the derivative of 1/f(x) is -f'(x)/(f(x))^2

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so its not really very clean

cyan saddle
#

I wanted to prove it

jagged imp
#

Uh you can use the quotient rule for this but I used the chain rule

#

with the "outside" function being g(u)=1/u and the "inside" function being f(x)

cyan saddle
#

Oh pretty smart.

#

Thanks

#

@jagged imp any way to prove the multiplication rule, using chain rule?

jagged imp
#

by multiplication rule you mean product rule(this)?

jagged imp
#

might be a language barrier thing but i've never heard it called multiplication rule

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anyway, its not proved with the chain rule

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you have to do it from the definition of the derivative/first principles

jagged imp
#

there's another method too i just found, i can link you to a site with both methods if you like

cyan saddle
#

Sure!

jagged imp
#

the other method than the limit definition is implicit/logarithmic differentiation if you wanted to try it yourself

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if you scroll down its listed under product rule

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there's also khan academy or something along those lines if you'd prefer a video

cyan saddle
#

That's alright, I think I got it

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Thanks a bunch

jagged imp
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nw mate

spare marsh
#

can someone help me make the venn diagram? I'm also confused on how to measure the percentage in part b for example, am I taking 36% of 43?

#

I think this is it?

sinful sail
#

any other ways to get the area of a circle than r x r x pi ?

jaunty plover
#

$A=\pi \left(\frac d2\right)^2$ ?

ocean sealBOT
#

PristineWolf

sinful sail
#

so A=Circumference x R:2 is not ok ?

jaunty plover
#

what's R?

sinful sail
#

radius

jaunty plover
#

no it's not okay

sinful sail
#

does it work ?

jaunty plover
#

no.

#

what you said is basically $A=C\cdot \frac R2$

ocean sealBOT
#

PristineWolf

jaunty plover
#

wait

#

wait

#

my bad my bad

#

@sinful sail your thing works as well

sinful sail
#

cool

jaunty plover
#

i misunderstood

vale wigeon
#

no

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-3/2 cos(2x),

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but also, if all you wanted is an answer, you could've gone to wolfram alpha

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try taking the derivative of $-\frac32 \cos(2x)$ and you'll see.

ocean sealBOT
vale wigeon
#

hopefully you will have enough sense not to claim that the derivative of cos(2x) is -sin(2).

#

the derivative of a composition is not the composition of the derivatives.

subtle mantle
#

If you want to know how you’d do it, you use a u substitution u=2x, du = 2dx so 3sin(2x)dx
-> 3/2sin(u)du and then you just integrate sin(u)du normally

vale wigeon
#

+C, but yes

#

you're trying to see a pattern where there isn't one

crisp grail
#

Some stuff js harder, if you do the y=2x substitution, it should be more clear

fading zephyr
#

set the two functions equal to each other

#

that is, 6x - x^2 = x + 4

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this is a quadratic and has 2 solutions, which are the values of x at which the curves intersect

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you then evaluate either of the two functions at these 2 values of x to get the y coordinate (it doesn't matter which function, since the two are equal at these values of x)

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this will yield 2 points of the form (x,y)

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is this a calculus course?

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ok

#

the area is an integral

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you can integrate the difference of the two functions

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and the integration limits are the x coordinates you just found

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the y values are the functions

unkempt stream
#

integrate top-bottom

fading zephyr
#

due to the linearity of integration, yes

#

it is rather integral (f2 - f1), but as you said, you can split this into two integrals

sharp sparrow
marble seal
#

hi guys

#

i'm solving this equation

2x + 2  -5 = 4x + 3
    ---          ---
     6            6```
#

x = 31
-----
12
right?

manic quail
#

$$2x+\frac26-5=4x+\frac36$$

ocean sealBOT
#

heuwuernwufntmkiearsetnuyyyf

manic quail
#

Do you mean this @marble seal ?

alpine sable
sharp sparrow
alpine sable
#

Lets move to another channel

marble seal
alpine sable
#

let @manic quail and @marble seal use this

sharp sparrow
#

okay what channel?

marble seal
manic quail
marble seal
manic quail
#

Okay, nice

#

,w solve 2x+\frac26-5=4x+\frac36

ocean sealBOT
marble seal
#

my answer is
x = 30
---
12

marble seal
manic quail
#

That isn't your answer though 0.0

manic quail
# marble seal noiiiiiiiiice

$$2x+\frac26-5=4x+\frac36 \ | \ -2x$$
$$\frac26-5=2x+\frac36 \ | \ - \frac36$$
$$-\frac16-5=2x \ | \ \times \frac12$$
$$x=\frac{-\frac{1}{6}-5}{2}$$

ocean sealBOT
#

heuwuernwufntmkiearsetnuyyyf

manic quail
#

and $$x=\frac{-\frac{1}{6}-5}{2} \Longleftrightarrow x=\frac{-1-30}{12}=\frac{-31}{12}$$

ocean sealBOT
#

heuwuernwufntmkiearsetnuyyyf

marble seal
#

why like this 😄

manic quail
#

I solved the equation, what do you mean?

marble seal
#

i solve it in easier way

manic quail
marble seal
manic quail
#

,rotate

ocean sealBOT
marble seal
manic quail
ocean sealBOT
marble seal
manic quail
#

,rotate

ocean sealBOT
manic quail
#

Okay, great, that's fine too.

marble seal
pliant roost
#

Hello, I got a question regarding a 3d world. I have 2 points. The point YOU are at, and the point you WANT to go to.
I get the distance in between these 2 points and I'll substitute it as D.
I would like to get the time it'd take to travel from point A to point B accounting for not only the X but also the Y
Right now I have
time = D / speed but I wanna also include the Y axis which this does not, how could I do such a thing?

subtle mantle
#

that's the correct formula for constant speed

pliant roost
#

but it doesn't count for the Y axis, only X

subtle mantle
#

what? yes it does

#

that's what D is for

pliant roost
#

fuckkk

#

my brain is broken

subtle mantle
#

it's the distance between the two points, i.e. for two points (x1, y1, z1), (x2, y2, z2) D = sqrt((x1-x2)^2+(y1-y2)^2+(z1-z2)^2)

#

so it takes all of the coordinates into account

pliant roost
#

yeah I see that now

#

okay thx lmao

subtle mantle
#

np

rotund osprey
#

can someone help me
(int from -inf to 230 (1/(sqrt(2pi)10)(e^((x-g)²/(210)))))=0.034
how can i get the average (g) out of this
its the gauss function

lean gust
#

no

#

z^3 not equal 3sqrt(z)

subtle mantle
#

no, that's $z^{\frac{3}{2}}-a^{\frac{3}{2}} = \sqrt{z^3}-\sqrt{a^3}$$

ocean sealBOT
#

Wew Lads Tbh
Compile Error! Click the errors reaction for more information.
(You may edit your message to recompile.)

subtle mantle
#

third try's the charm

ornate peak
#

@subtle mantle @lean gust thank you

lean gust
#

somenone have a exemple test of math in english level (terminale or prepa ) last years of high school or first year of university in maths or physique

marble seal
#

can i know the solution of this plz

subtle mantle
#

just write / for fractions

#

it's so much more readable

lean gust
#

write in paper it's not clear

marble seal
#

x +10 15 - x 12 2x - 12
------ - ( --------- - ------- ) = -----------
6 3 2 18

lean gust
#

ah

marble seal
#

better?

lean gust
#

yes

subtle mantle
#

(x+10)/6-((15-x)/3-6) = (2x-12)/18

marble seal
#

my answer

x = 156
-----
-5

#

,solve (x+10)/6-((15-x)/3-6) = (2x-12)/18

alpine sable
#

,calculate (x+10)/6-((15-x)/3-6) = (2x-12)/18

ocean sealBOT
#

The following error occured while calculating:
Error: Invalid left hand side of assignment operator = (char 29)

marble seal
#

😦

lean gust
#

3x/18 -2x/18 -6x/18 = -12/18 +90/18 -108/18

#

-5x/18 = -30/18

#

5x=30

marble seal
lean gust
#

x=6

marble seal
#

i did it + 108

lean gust
#
    • 12/2
#

+12/2=.....

marble seal
#

wait

lean gust
#

108/18=....

#

...=-108/18

marble seal
#

yes

#

no

#

wait what

lean gust
#

i haven'ta good computer

marble seal
#

why i did it + 108

#

lol

#

i just did
3x + 30 - 90 - 6x - 108 = 2x - 12

marble seal
lean gust
#

x +10 15 - x 12 2x - 12
------ - ( --------- - ------- ) = -----------
6 3 2 18

#

x +10 15 - x 12 2x - 12
------ - --------- + ------- = -----------
6 3 2 18

#

x +10 15 - x - 12 2x - 12
------ - --------- = ------- + -----------
6 3 2 18

marble seal
#

in the middle

lean gust
#

where

marble seal
#

oh u removed the bracket so the sign changed

marble seal
lean gust
#

3x 3*(10) 3* (15) -3x - 3* ( 12 ) 2x 12
--- + --- - ----- ---- = ------- + ------ - ----- 36 3 6 3 3 2 18 18

glass lichen
#

tf is that formatting?

marble seal
lean gust
#

3x 3*(10) 3* (15) -3x - 3* ( 12 ) 2x 12
--- + --- - ----- ---- = ------- + ------ - ----- 36 3 6 3 3 2 18 18

marble seal
lean gust
#

Okok

alpine sable
#

is anyone good here with science

#

like cell cycles

dusk gazelle
#

yoo

#

give me a hard one

rotund osprey
#

find x

dusk gazelle
#

of what ?

#

the equation ?

dusk gazelle
marble seal
#

hi guys , can i just know how to solve this in a simple and step by step way? (please be simple)

2x - z = 4
3y + z = 2```
dusk gazelle
#

hmm

#

I forgot it lmao

glass lichen
#

dont suggest breaking rules..

dusk gazelle
#

lol

dusk gazelle
glass lichen
#

ie augmented matrices

dusk gazelle
#

I forgot it

glass lichen
#

wasnt asking you

dusk gazelle
#

I know

#

I trying to solve it

marble seal
glass lichen
#

ok so from eqn 1, what's z?

dusk gazelle
#

we dont know

#

we need to find z first maybe ?

knotty sleet
#

Why wouldn't you just use elimination?

#

Sorry for interrupting

dusk gazelle
#

np

#

I tried but forgot how

knotty sleet
#

Oh are they required to use matrices

glass lichen
dusk gazelle
#

bruuh

#

okay am out

#

😕

glass lichen
knotty sleet
#

Ah right kk👍

glass lichen
#

From equation 1, $$z=5-x-y$$ this means that 1a into 2 and 3 gives $$2x-(5-x-y)=4$$ and $$3y+(5-x-y)=2$$

ocean sealBOT
alpine sable
#

can someone explain me whats here?=

drifting jacinth
#

what do you mean ?

plucky crow
#

from the two equations below

scarlet spire
#

yo sorry if im interrupting something but is a horizontal compression by a factor of 1/2 the same as a horizontal stretch by a factor of 2

alpine sable
#

Can anyone help undestrand how should I work out the x-coordinate of G?

#

For the y-coordinate it's just a triangle but I cant figure out the relation between s and xG

sour echo
#

<@&286206848099549185>

plucky crow
#

ill try

#

dms

sour echo
#

ooo ok thanks

lost moss
shut elk
#

what's up @lost moss ?

#

are you asking what the solution is?

lost moss
#

yes

shut elk
#

have you tried?

lost moss
#

yes im just to stupid

shut elk
#

not possible, explain how you've tried

alpine sable
#

can someone explain how to do this?

#

it says 4+i ; 4-i ; -2 by the way

jagged trout
# marble seal hi guys , can i just know how to solve this in a simple and step by step way? (p...

This precalculus video tutorial provides a basic introduction into the gaussian elimination - a process that involves elementary row operations with 3x3 matrices which allows you to solve a system of linear equations with 3 variables. You need to convert the system of equations into an augmented matrix and use matrix row operations to write it ...

▶ Play video
marble seal
marble seal
alpine sable
silk terrace
#

I need to find the taylor series for the function and show that it converges. Could someone help with the approach?

#

I have found the taylor series of exp(t^3) but am unsure on how to continue from here.

#

Does integrating from 0 to t yield the desired taylor series?

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I thought it was open. My bad. Thanks

viscid junco
#

is it resolved now

silk terrace
#

Oh so it is still me

viscid junco
#

ok

silk terrace
#

Okay; I have seen the example but I am still unsure since i integrate from 0 to x

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and not 0 to 1

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Isn't that the same as taking the indefinite integral and have c=0?

#

So just integrate each term of the taylor series of exp(t^3)

hollow pelican
#

guys does anyone know how to do this?

rigid smelt
#

what have you tried?

hollow pelican
#

i solved it

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but im not sure if need to put brackets anot

viscid junco
#

with or without are both fine

lean gust
coral pagoda
ocean sealBOT
#

dackid (jump king +)

silk terrace
#

So I am essentially integrating each term in the series

coral pagoda
#

Exactly

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And this is something you can do in the radius of convergence

silk terrace
#

So I found to be the taylor series of exp(t^3).

coral pagoda
silk terrace
#

I see that now! So I can integrate directly in a sum?

alpine sable
#

@coral pagoda

coral pagoda
#

Yep, mainly because the Maclaurin series for e^u is convergent for all u. So when u=t^3, the taylor series also converges.

alpine sable
#

is there anyway you can help me if i dm you something

coral pagoda
#

No, this is the only problem I am helping with. I have other things to do today

alpine sable
#

k

coral pagoda
silk terrace
#

Okay so the whole problem is essentially this. The taylor series is given by the integral from 0 to t wrt x of the sum that you linked. Then I have to give an argument that the taylor series must converge to my function for all x

coral pagoda
#

That's super easy to do. Just use the ratio test

silk terrace
#

To show that the taylor series must converge to my function for all x is the same as finding the radius of my taylor series to be infinity?

coral pagoda
#

Indeed

silk terrace
#

got it. the only thing left to do is integrating then

#

Thanks!

coral pagoda
#

Sure is! Happy to help mate

silk terrace
#

wait it is from 0 to x wrt t right?

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not the other way around

coral pagoda
#

Correct

sour echo
#

@lost moss

random crypt
#

Is the channel in use ?...

alpine sable
#

Can anyone help undestrand how should I work out the x-coordinate of G?

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Can anyone help me understand how should I work out the x-coordinate of G?
For the y-coordinate it's just a triangle but I cant figure out the relation between s and xG.
It's a rotating half disk
does not really say anything apart from this

#

G is the barycenter of the disk
i can find it's y-coordinate just by tackign l-lsin\theta where l is the height of the line with A
but i cant seem do find anything for the x-coordinate

dense snow
#

Anyone can do this?

fluid ember
#

@dense snow Is that a SAT mathlevel2 question?

dense snow
wraith phoenix
#

@here

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can anyone help out?

wet fulcrum
#

oh my bad channel in use

wraith phoenix
#

any body?!1

random crypt
#

Which channel can I use to ask questions ?....

fluid ember
#

@random crypt any that is free

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this aint btw

fluid ember
#

how about this

fluid ember
#

wdym?

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it says N^2/100

dense snow
#

no like why is it 8?

#

oh

#

wait

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stupid me, sorry XD

fluid ember
#

np lol

fresh parcel
#

no thats just gauss 8

jagged trout
#

why 8?

fresh parcel
#

N is 41 because 129^2 mod 100 is 41

fluid ember
#

it says positive integer

#

the 2 lines can only be 8 no?

jagged trout
#

When I understand this right, then we have a 6x6 square in the middle to build the rectangles

fervent holly
#

Is the minimum relation of an equation the vertex?

calm grove
random crypt
autumn apex
#

@random crypt do you know what it's asking?

random crypt
#

Uhh kinda

autumn apex
#

you're given the derivative factorized. critical numbers are when the derivative is zero, right?

random crypt
#

Yeah

autumn apex
#

if you have a factorized polynomial of a single variable, how do you read off the roots?

random crypt
#

But why would they give me factorixed. It makes things harder

#

Right..?

autumn apex
#

nope, easier

random crypt
#

Obv

#

Oh *

distant bay
#

Hi

#

Could someone help me with an exponential problem

autumn apex
#

this channel is taken

distant bay
#

🥺my bad

autumn apex
#

@random crypt so if you have an expression like f(x) = (x+2)(x-3), if either of the terms in parenthesis is 0, the whole expression is zero, so you have a root

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how would you make one of the terms in parenthesis equal to zero?

random crypt
#

X+2= 0 ; x=-2

#

Like that?

autumn apex
#

how do you pick x such that it sends (x+2) to zero

#

and how do you pick x such that it sends (x-3) to zero

#

both of those selections of x are roots

random crypt
#

Factor

#

Then find x?...

autumn apex
#

you're already given the factored expression

#

so the roots of f(x) = (x+2)(x-3) would be x=-2, x=3

#

make sense?

random crypt
#

Yes

#

So

autumn apex
#

what are the roots of f(x) = (x+2)^4

random crypt
#

5,-2,0

autumn apex
#

where'd you get that from

random crypt
#

From the whole equation

autumn apex
#

oh that's your whole answer

random crypt
#

Yeah

autumn apex
#

yep you got it

random crypt
#

So what’s next

#

I found the x

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What do I do now

#

To find the critical #

autumn apex
#

as easy as checking the definition of critical number

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they're the roots of a derivative of a function, and you have the derivative of a function

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so you have the answer

random crypt
#

Ohhh that’s it ?...

autumn apex
#

yep 🙂

random crypt
#

Then how do I find if the intervals of increase or decrease of F

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@autumn apex

autumn apex
#

so when is a function increasing, given its derivative?

random crypt
#

F>0

autumn apex
#

yep

random crypt
#

Ok

autumn apex
#

from roots of the derivative, you know the endpoints of the intervals

random crypt
#

You mean the critical points right ?

#

X=0,-5,-2

autumn apex
#

the critical points of f are the roots of the derivative of f, same thing

random crypt
#

Ok

#

Then what

autumn apex
#

check if the derivative is positive or negative between each interval -- it has to be only one of these, since for the answer to change it must cross zero

random crypt
#

So do I plug in the critical numbers in the function

autumn apex
#

you can check the value between them

random crypt
#

Like between 0 and -5?...

thorn sky
#

Help

autumn apex
#

channel is taken

#

so your intervals are [-inf, -2], [-2, 0], [0, 5], [5, inf] (don't forget the 5 is positive)

random crypt
#

Why is the flag positive

#

5

#

I thought we said the five was a negative

autumn apex
random crypt
#

Ohh

autumn apex
#

you swapped it a few minutes later

random crypt
#

Ohh

#

Sorry

#

Do I plug in a number between negative infinity and -2 into the function?...

autumn apex
#

yep

#

any will do

random crypt
#

So ex: -1?

autumn apex
#

yep, I'd do -3, -1, 1, 6

#

channel is taken

random crypt
#

Give me one second I’m plugging everything in and I’ll show you what I did

dense snow
thorn sky
#

As

#

As

#

A

#

As

random crypt
#

@autumn apex

autumn apex
#

looks right

random crypt
#

So then what do I do

autumn apex
random crypt
#

We were trying to find the interval of increase or decrease of f

autumn apex
#

if a function's derivative is positive in a given interval, you know that function is increasing in that interval

#

use the sign of the derivative at each value you checked to decide for that interval

barren furnace
#

🤷

autumn apex
#

channel is taken.

random crypt
#

OK I know if f’>0 then it’s increasing and vide versa

#

Vise

#

After I figure it out and plugged all these numbers in

#

I don’t know how to tell which one is increasing or decreasing

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@autumn apex

random crypt
autumn apex
#

you calculated values where f'>0 and f'<0, so you know where f is increasing and decreasing, right?

random crypt
#

They all came out negative except f’(1)

autumn apex
#

yep

random crypt
#

Is this right ?...

autumn apex
#

so if you want a local maximum, and you know two adjacent intervals (shared critical point) have negative derivatives...

#

yep

#

channel is taken

random crypt
#

So what does it mean to find the location of the local maximum and the local minimum

autumn apex
#

if a function's derivative is 0 at a point you know, and the interval on either side is negative, what does that imply for the original function at that point you know?

random crypt
#

So I know that the derivative is X=0

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It’s one of the derivatives

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**

#

It implies that it’s interval decreases

autumn apex
#

on both sides, yep

halcyon leaf
autumn apex
#

channel taken.

halcyon leaf
#

Can someone please help me?

autumn apex
#

please ask in an open channel instead

halcyon leaf
#

so which channel?

#

generla?

autumn apex
#

check for one where the last question asked has been answered

halcyon leaf
#

k

autumn apex
#

so @random crypt if you know the function decreases on either side of this value, what does that imply (in terms of local minima and maxima) for that function?

random crypt
#

The point where it most decreases is the local minimum?...

#

I’m not sure to be honest

autumn apex
#

think about it like this -- is f decreasing or increasing or neither when f' = 0 (remember, f'(-2) = 0)

random crypt
#

Increasing

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Because I plugged it into a function

autumn apex
#

so f' > 0 means f is increasing, right?

random crypt
#

Yes

autumn apex
#

what about when f' = 0

naive dock
#

hi

random crypt
#

It’s the same

#

Neither

autumn apex
#

channel is taken @naive dock

naive dock
#

am soory

random crypt
#

But it’s not decreasing or increasing

autumn apex
#

right, you might want to plot a parabola on a sheet of paper and think about it for a moment

random crypt
#

Ok

#

I just sketched a parabola on paper

quartz sage
#

If anyone can help me, I’m in #help-4

autumn apex
#

so if the parabola opens upward, where is the minimum

random crypt
#

0

#

Like zero is the lowest part

autumn apex
#

for f(x) = x^2 yes

random crypt
#

Is that what you’re asking

autumn apex
#

yes, just trying to get you to understand the local minima/maxima are able to be understood in terms of the derivative

#

so what is the derivative at that point?

#

and is f increasing or decreasing on either side?

random crypt
#

I have a function already graft in front of me

autumn apex
#

local minima and maxima are also referred to as stationary points, i.e. derivative is zero

random crypt
autumn apex
#

yeah unfortunately the scale makes it a bit hard to tell

random crypt
#

Is it like this

autumn apex
#

plot from -4 to 0 to see

random crypt
#

Nothing At -4,0

autumn apex
#

that's looking like -4.5 to -3

random crypt
#

I think it says the maximum is negative to zero but I don’t know how they got there

#

-2,0 *^

autumn apex
#

it should look like this

random crypt
#

Oh

#

Can I see that graph

random crypt
#

Ok

#

How am I supposed to use the answer for part B to find the locations of the local maximum local minimum

#

Because I’m not allowed to use it from a graph

autumn apex
#

you know what local minima and maxima are, right?

#

what happens to a function on either side of a local maximum? Decrease or increase?

random crypt
#

Increase

#

Like it’s the height pint in a graph

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And local min is the lowest point on graph

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Highest *^

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Point *^

autumn apex
#

you've got it reversed

random crypt
#

Oh

autumn apex
#

a parabola opening upwards has a minimum but no maximum

random crypt
#

And vice Versa ??

autumn apex
#

a parabola opening downwards has a maximum but no minimum, and you know the function on either side of a downward opening parabola is doing what, increasing or decreasing?

alpine sable
#

the first derivative

random crypt
#

Decreasing?... because it’s going downwards ?...

autumn apex
#

right

#

so local maximum means 'the function is decreasing on either side'

random crypt
#

So does that mean the local minimum means the function is increasing on either side

autumn apex
#

yep

random crypt
#

Ohhh

#

So I already found at the interval increases from 0 to 5

#

Does that mean I already found my local minimum????

autumn apex
#

you know things about f' which tell you whether f is increasing or decreasing

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you know f'(-2) = 0, so f can't be increasing or decreasing at that value

#

kinda like the symmetry point of the parabola, right?

random crypt
#

Yaha

autumn apex
#

and you know on either side f'<0, which means f is doing what on either side, increasing or decreasing?

random crypt
#

Decreasing

#

Right?...

autumn apex
#

yep

#

so if you know f(-2) is a stationary point, you have two options for what happens on either side of f(-2), both increasing or both decreasing

random crypt
#

Yeha

#

So f(-2) is increasing

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Bc it’s less than 0

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And f’(x) > 0 is increasing

autumn apex
#

f(-2) increasing would mean f'(-2) > 0

#

is that the case?

random crypt
#

Uhh

#

But I thought we said if F(-2) = 0

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So it’s neither

autumn apex
#

correct

random crypt
#

Ok ok

#

So when the question as to find a location

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Does that mean we have to give a certain exact point

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Or not

autumn apex
#

yes

#

so "where is the local maximum of f given F" is the same as "around what point is f decreasing on both sides"

random crypt
#

But we really got where it decreases

#

So where in decreases is what it means to say the local maximum ?

#

I’m so dumb. I’m sorry

autumn apex
#

the derivative of f will be zero at a maximum or minimum

#

you know where those points are

random crypt
#

-2

autumn apex
#

you have a set of possibilities: f is increasing AND decreasing around a point == NOT a stationary point == NOT a maximum or minimum; f is decreasing on either side of a point == local maximum; f is increasing on either side of a point == local minimum

#

you only need to evaluate this around the critical points, and use your answer from b that had info about f decreasing and increasing in the various intervals

#

the answer must be a critical point, f' = 0

random crypt
#

Can you please show me on paper what you’re talking about because I think I understand what you’re saying but ...

#

How am I supposed to know that this point can be increasing or decreasing

autumn apex
#

the derivative carries that information

#

you know everywhere f is increasing or decreasing already -- you did that bit

random crypt
#

On

#

Ok

autumn apex
#

when I said 'f is increasing AND decreasing == NOT a stationary point' that means that value won't be one of the ones you found (-2, 0, 5), so that isn't a case you're worried about

random crypt
#

So if it’s the most negative then it’s the local maximum which means it’s 5, infinity ?....

autumn apex
#

you're looking for local minima and maxima, and there's one of each in this case. Knowing what happens around the critical points tells you which of the exactly 3 possibilities is true for that point: local maximum (a stationary point), local minimum (a stationary point), neither (not a stationary point)

#

channel is taken

fluid ember
#

Mb

random crypt
#

I apologize. This is my third time retaking this class

#

I’m failing it for a reason

#

I Understand what you’re saying but it’s just not clicking

autumn apex
#

you're clear on what a local maximum and minimum are though, right?

#

and that when I say stationary point, I mean one of those two possibilities

random crypt
#

That if F is decreasing on either side and it is local max

#

F is increasing on either side it has a local minimum

autumn apex
#

and you know 'increasing on either side' means, if I move left OR right from this point, I get a higher value

random crypt
#

Yes

autumn apex
#

and that if a function is increasing on either side, it must 'level off' at that point?

#

i.e. derivative of the function is zero there

random crypt
#

Yes

autumn apex
#

so you have a set of information which is necessary to find the answer of 'where are the stationary points'

#

what information do you use?

random crypt
#

The critical points?...

autumn apex
#

you use whether or not the function increases/decreases on both sides of the critical points

random crypt
#

How do I do that

#

Like I already chose for numbers that’s in between the critical points

#

And I already sent that to you

autumn apex
#

the critical points tell you where the function's derivative is zero

#

and "function's derivative is zero" means "stationary point"

random crypt
#

I already plugged in the critical points and none of them came out zero

autumn apex
#

the critical points are exactly the ones where f'=0

#

don't lose track of what you're trying to find out

#

what would it mean for f(-2) to be a stationary point?

#

could it be increasing on one side and decreasing on the other?

random crypt
#

So if F is any of the critical points that means zero

autumn apex
#

yep, "critical point" is just a term that lets you talk about the "critical points of f" which is information about F

#

namely, F=0

random crypt
#

What do I plug in and what do I do to know exactly which one is that local l maximum/min

#

Like I’m understanding everything you’re saying it’s just I don’t know which one is a local Max on which one is the local minimum

autumn apex
#

also just to be clear, you're using F to mean derivative of f, right?

random crypt
#

Yes

autumn apex
#

a local maximum, in terms of critical points, is "to the left AND right of this critical point of f (F=0), f is decreasing (F<0)"

#

a local minimum, in terms of critical points, is "to the left AND right of this critical point of f (F=0), f is increasing (F>0)"

#

f(-2) is a local maximum because f decreases on either side, and you know this from your previous answer

random crypt
#

I thought -2 was one of the critical numbers

autumn apex
#

it is

#

in order to be a local maximum or minimum it must be a critical number

#

a function can't decrease on both sides or increase on both sides of a point unless it's a critical number

#

barring the case of a singularity, but not relevant here

random crypt
#

Can you show me a piece of paper how you found that -2 Decreased on both sides

autumn apex
#

the graph I linked shows it

#

this is f' or F

#

it's a bit hard to tell but at -2, the curve touches y=0

#

you already know this though, F(-2) = 0 from part a

#

and YOU found out that f decreases on either side by checking a value inside each interval

#

the signs of the values you found by plugging in values -3, -1, 1, 6 tell you whether f is increasing or decreasing, because they told you whether F>0 or F<0 at those points

#

so you know f(-2) is decreasing on either side because you checked at -3 and -1 and determined F<0 for both

#

^^^

random crypt
#

Is is f(6) is the local min

#

F(5)

#

I’m literally the most stupidest human you’ll ever meet

#

There’s a reason I failed this class twice

autumn apex
#

it's important to take breaks if you've been working too long

#

brain doesn't work great without breaks

random crypt
#

I’m sorry if I wasted your time

#

I’m just trying my best to learn

autumn apex
#

it's ok I just had to make sure I wasn't giving a wrong answer

#

the places where the derivative of f equals 0, i.e. -2, 0, 5, are the places where f changes direction

#

so critical points are where local minima and maxima are

#

I may have inadvertently confused you by using increasing and decreasing the way I did

random crypt
#

No no. Trust me. The amount of ppl that tried to explain calculus to me is insane.

#

You’re the best person of explaining it to me.

#

I understood from you the most

autumn apex
#

a good way to develop the intuition would be to plot the derivative you were given (F) and its integral (f)

#

you'll see what the function does relative to its derivative, and how the values of the derivative associate to minima and maxima of f

random crypt
#

I appreciate your patience

#

W me

autumn apex
#

np

random crypt
#

And helping me step by step

autumn apex
#

I can't stress enough, you should take a break if you haven't

#

brain drain will take you from perfectly competent at calculus to 'how does algebra work'

random crypt
#

I’ll try. I kinda can’t Bc I work 3 jobs supporting my family. And right now is the only time I can finish my school work

autumn apex
#

oh you only need to take a few minutes for a break

#

trust me, working a problem straight through without breaks while you're brain drained will take longer than doing the problem with breaks

random crypt
#

I appreciate it.

#

Will do

native temple
#

Can x^2 = 4py be converted to ax^2 + bx + c = y?

calm grove
obtuse cove
#

Can I receive help on these two questions? 🤣

#

Or is this channel closed?

sharp flare
#

In

9 51 15/17
— = —————
17 98

15/17 Put Into A Decimal Is 0.882......

And 9 x 98 is 882

Is this just a coincidence?

quartz sage
#

I THINK NOT

sharp flare
#

Lol

#

But seriously tho does anyone know

native temple
calm grove
#

The formula is -b/2a for x coordinate of the vertex and if you put x=-b/2a in eqn you shall get y coordinate
Of the vertex too

alpine sable
#

The marks obtained by four students in a math test are displayed in the table shown here.

Which of the following ranges is most appropriate to represent the numerical data on the vertical axis of a Bar Chart?

A.    10 to 50
B.    0 to 100
C.    0 to 50
D.    10 to 100
sharp flare
#

I suck at charts but I’m pretty sure it has to be B or D as A and C don’t go to 100

alpine sable
#

maybe its d because the lowest score is 45% so it isnt necessary to go to 0

sharp flare
#

yeah

#

Rawrbin said D

#

That should be right

alpine sable
#

thank you

sharp flare
#

Lol thank rawrbin

#

Hey rawrbin

#

In

9 51 15/17
— = —————
17 98

15/17 Put Into A Decimal Is 0.882......

And 9 x 98 is 882

Is this just a coincidence?

autumn apex
#

it's a coincidence.

sharp flare
#

Lol

#

I’ve been looking over this for an hour

#

Trying to find a formula that gets something like this

alpine sable
#

This Bar Chart shows the weight in kilograms of fruits sold in one day.

Why is the Bar Chart misleading?

A.    The heights of the bars do not represent the correct numbers.
B.    The vertical axis shows unequal intervals.
C.    The horizontal axis is missing one type of fruit.
D.    The width of the bar representing Jackfruit is more than the width of other bars.
#

i got another

autumn apex
#

9*98 / 1000 = (3^2)(7^2)/(2^2)(5^3) ~= (3)(5)/(17)

quartz sage
#

can someone help?

autumn apex
#

I think this channel is taken

quartz sage
#

damn

sharp flare
#

Lol I’m in middle school i don’t know any of that stuff so queque

#

DONQUEQOR

autumn apex
#

you can factorize ratios of integers into prime numbers and compare them more directly

sharp flare
#

Oh WAIT

alpine sable
#

thank you again rawrbin

sharp flare
#

nvm I know that I just didn’t know what the arrow sign meant

alpine sable
#

why is 8th grade math so hard

autumn apex
#

if you mean ~= yeah that's a bad font, just means approximately

sharp flare
#

oh I mean like the ^

#

is that just multiplication

autumn apex
#

exponent

sharp flare
#

Oh ok

#

Thx

autumn apex
#

np

sharp flare
#

So the exponent here would be what?

autumn apex
#

there are several exponents in what I posted

sharp flare
#

oh duh

#

Si the first exponent would be 98*9

autumn apex
#

nope that's multiplication

sharp flare
#

I’m smooth brain

autumn apex
#

so if you have 2^3 that means 2 times 2 times 2

sharp flare
#

OH

#

That’s what you mean

autumn apex
#

just count how many multiplicative 2's you throw together

sharp flare
#

I thought u meant like ^ as a place holder

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Like x or y

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Thx

versed osprey
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A particle is moving in a circle of diameter 20m. What is its displacement in 1 round, 1.5 rounds, 2 rounds, and 2.5 rounds

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could someone explain this

autumn apex
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you're missing a part of your problem

versed osprey
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oh crap

autumn apex
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what is a 'round' in terms of the movement of the particle

versed osprey
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the problem asks for distance

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aahhaha

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nvmnvm

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thanks

autumn apex
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np

versed osprey
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wait shit it gave a table too

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ill just send a pic

alpine sable
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This Bar Graph shows the percent increase in the prices from the year 1981 to 1999.

What is a problem with the way this graph has been drawn?

A.    The scale along the vertical axis is divided into unequal intervals.
B.    The widths of the bars are not equal.
C.    The vertical scale used is too large for this data.
D.    The heights of the bars do not represent the correct percent increase.
versed osprey
alpine sable
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thank you again rawrbin :)

surreal delta
versed osprey
autumn apex
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part of this question still seems to be missing

surreal delta
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Okay hang on, I know how to solve it😄

versed osprey
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this is what it says online, still dont get it

autumn apex
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oh wait by 'rounds' do they mean full orbits?

versed osprey
autumn apex
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agh what a horrible use of terminology

versed osprey
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sorry i shoulve menitoned

autumn apex
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np

versed osprey
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*mentioned

autumn apex
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so what's the displacement of a particle if it goes around the circle once?

versed osprey
versed osprey
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*this

autumn apex
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displacement being distance [accumulated] between start point and end point

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and presumably 'distance' here means how long was its path

native temple
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IDK how to complete square outside of this form ax^2 + bx + c = y

autumn apex
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so you accumulate perimeter as you travel (distance), but if you travel an integer multiple of a round the displacement must remain zero

native temple
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How to solve this?

surreal delta
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@versed osprey

circumference = diameterpi
= 20
3.14
1 circle = 1circumference
1.5 circles = 1.5
circumference
This is how to solve distance😄

surreal delta
gloomy lintel
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Yeah I can’t read it either

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Could you send a clearer pic please?

native temple
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sure

versed osprey
autumn apex
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displacement is at most one diameter, it's the distance between the start point and end point ignoring the path you took

native temple