#help-27

1 messages · Page 326 of 1

finite briar
#

💀

#

sorry

#

well its bromine

hollow ice
#

what do you think that A does?

#

in paint

finite briar
#

thanks

#

the name, if u know

#

3-methyl,bromomethyl-5-methylhexanol

hollow ice
#

methyls should be grouped and thats bromomethyl and not bromoethyl

finite briar
#

is my new guess

finite briar
hollow ice
#

yea

finite briar
#

i see, thank u

hollow ice
#

hex-1-ol i think

finite briar
#

isnt hexan-1-ol

#

just hexanol

hollow ice
#

idk

#

I hate organic and havent touched it in almost 7 years

finite briar
#

💀

final osprey
#

idt locant is important for alcohol here

finite briar
#

this one is a question from my notes but i seem to have written ethane-1,2-dial forgetting the double bond

#

so i think this shud simply be

#

ethene-1,2-dial or ethenedial

final osprey
#

that isnt aldehdye

finite briar
#

OH WAIT

#

this is wrong

#

okay yeah

#

i know what went wrong

#

this is bs

#

sorry 🙏

#

thank u

#

.close

devout snowBOT
#
Channel closed

Closed by @finite briar

Use .reopen if this was a mistake.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

restive river
devout snowBOT
restive river
#

Why are they using 3ab^2 here from pascal's triangle for x^2.?

timber pebble
#

you dont need to think of it as directly from the triangle

#

just write out the 3 factors

#

(2-cx) (2-cx) (2-cx)

#

we need two cx and by necessity one 2

#

3 ways to exclude a cx

#

does that help?

restive river
#

I dont understand what you mean

#

Am i supposed to only expand 2 brackets?

timber pebble
#

no, we are imagining picking out pieces of the distribution

#

so you select one term from each factor

#

we must select exactly two cx

#

or we wont get x squared

#

does that make sense?

restive river
#

I think I understand

#

I need to write out the whole equation but onlu pick out the part that has an x^2

timber pebble
#

you dont have to write it all out

restive river
#

which expands to 6c^2x^2

timber pebble
#

we can kind of imagine how the distribution will happen

timber pebble
#

because eventually every term hits every other

restive river
#

ohh because its only to the power of 3

timber pebble
#

right?

#

i mean imagine it were just this

#

(2-cx) (2-cx)

#

we want all the x terms

restive river
#

im genuinly so lost on what you mean with the 2 brackets

timber pebble
#

imagine which parts of the distribution will donate x terms

restive river
#

do i expand them

timber pebble
#

no

restive river
#

or what exactly do i do with them

timber pebble
#

select one term from each factor

#

to create the power you want

restive river
#

okay

timber pebble
#

since in distribution all the terms you select will be multiplied

restive river
#

can i pick two (-cx)

timber pebble
#

so if you want only x terms

#

you only pick one x term

#

(2-cx) (2-cx)

#

we can either pick one from the first factor

#

or one from the second

#

this tells us that the coefficient on the x term in the expansion will be 2 (times stuff)

#

i hope that makes some kind of sense

#

maybe it is easier to just say how to read the triangle

restive river
#

Ive not gone on to the factiorial notation or binomail expansion yet maybe im missing something

#

Because I dont understand how you would just pick

#

and what you would even do with the pick

timber pebble
#

lets do an easier one

#

is that okay

restive river
#

yeah

#

ill do it

timber pebble
#

(1+x)(1+x)

#

there are 4 terms in the expansion right

restive river
#

yeah

timber pebble
#

1 + x + x + xx

restive river
#

yeah

timber pebble
#

this comes from pairing up terms in the factors

#

and taking their product

#

then adding everything up

restive river
#

youve just expanded the brackets?

timber pebble
#

yea

#

you heard FOIL before

#

describes the four pairs you get

restive river
#

its a way of expanding brackets

timber pebble
#

instead of expanding everything

#

we can just select the pairs we know will give us relevant terms

restive river
#

ohhh sure

timber pebble
#

we know there are 4 pairs

restive river
#

i can understand that

timber pebble
#

only some give x^1

restive river
#

if we want the x^2 we pick the pair that gives us that

timber pebble
#

so we stare at(x+1)(x+1)

#

imagine taking x from the first and 1 frm the second

#

or visa versa

#

we dont expand everything

restive river
#

okay

timber pebble
#

we just pick the pairs

#

how about (x+1)(x+1)(x+1)

#

can you pick out the x coefficient?

#

now we want triplets

restive river
#

is it 3x

timber pebble
#

yea

#

we take x 1 1

#

or 1 x 1 ...

restive river
#

wait

timber pebble
#

you can try picking up factors

restive river
#

are we picking out in pairs of 3

#

do we need to take something from everything

timber pebble
#

(1+x)(2+x)(3+x)

timber pebble
#

one term from each factor

restive river
#

ahhh i see

timber pebble
#

actually

#

do x squared

restive river
#

3x or 6x or 2x

timber pebble
#

yea

restive river
#

3x^2, 2x^2 and x^2

timber pebble
#

,w distribute (1+x)(2+x)(3+x)

timber pebble
#

theres 11

#

make sense?

restive river
#

ahhhhhh

#

i think i understand

timber pebble
restive river
#

you pick them out and then add them like they would be added in the equation without doing all the extra

timber pebble
#

yea

#

just do the terms you want

restive river
#

alright lemme try the og again

timber pebble
#

okay

restive river
#

alright i see you would get 2(3)C^2X^2

#

I understand thank you

timber pebble
#

np

restive river
#

is there a name for this btw?

#

Just so I can put it in my notes

timber pebble
#

im not sure

#

i mean really, were working out entries of the triangle

#

or counting out the actual binomial coeficient

#

but this will work even outside of binomials

#

sorry not sure

restive river
#

its fine thanks again

#

.close

devout snowBOT
#
Channel closed

Closed by @flint owl

Use .reopen if this was a mistake.

devout snowBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

light pecan
#

does anyone have any tips for teaching the intro to differential calculus? mate of mine is in year 11 and starting soon and would love to help him

pseudo basin
#

start with some simple functions and their derivatives

#

work your way through all the rules and make sure your friend understands it all

light pecan
#

this is before he knows what a derivative is

pseudo basin
#

and practice plenty

pseudo basin
light pecan
#

i meant like beginning beginning

#

infinitesimal change

pseudo basin
#

ig send him to khanacademy

light pecan
#

fair enough

#

do you remember how your first 'lesson' was

stone stump
#

we had a function which gave us the distance that some runner runs in some time. then we were asked the average speed in some time spans which got shorther and shorter

light pecan
#

thats a cool idea

stone stump
#

I assume this and variations is fairly standard

light pecan
#

i remember something like that

#

anyway ill have a look

#

thought i should ask around

#

.close

devout snowBOT
#
Channel closed

Closed by @light pecan

Use .reopen if this was a mistake.

devout snowBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

viral lynx
devout snowBOT
iron kindle
viral lynx
iron kindle
#

whats your question

viral lynx
#

(2x - 3)(e^2x-1) = 6x - 9

#

(2x - 3)(e^2x-1) = 3(2x - 3)

#

e^(2x-1) = 3 and 2x - 3 = 0

#

x = (ln(3) + 1)/2 and x = 3/2

iron kindle
#

BRACKETS

pure flower
#

oh it's him again

viral lynx
iron kindle
viral lynx
#

Ah

iron kindle
#

e^(2x-1)

viral lynx
#

So x1 is obviously 3/2

#

(ln(3) + 1)/2

#

ln(3)/2 + 1/2

#

ln(sqrt(3)) + ln(sqrt(e))

#

ln(sqrt(3) * sqrt(e))

#

ln(sqrt(3e)) ?

#

Is that allowed?

iron kindle
#

yes

#

$\sqrt{a}\cdot\sqrt{b}=\sqrt{ab}$ if $a,b\geq 0$

woven radishBOT
viral lynx
#

Awesome

#

So c is just 3e?

iron kindle
#

yup

pseudo basin
iron kindle
#

and x1?

viral lynx
#

3/2

iron kindle
#

yup

viral lynx
#

Noiceeee

iron kindle
#

so what exactly was the problem?

#

haha

viral lynx
#

I wasnt sure how to do it really

#

But you guided me haha

#

Thank you!!

#

❤️

iron kindle
#

i didnt do shit lol

#

haha

viral lynx
#

You did 😂

#

.close

devout snowBOT
#
Channel closed

Closed by @viral lynx

Use .reopen if this was a mistake.

viral lynx
#

Bonk is so humble 😝

iron kindle
#

look back

#

what did i do

#

lol

viral lynx
#

Im teasingggg

pure flower
viral lynx
pure flower
#

and it seems to always be the case that whenever he's here we just stay in chat and watch him type for 5 minutes

#

until he goes 'oh i got it'

#

lmao

viral lynx
#

You dont have to wait...

#

You can go do other things

twin spoke
#

but that's good

iron kindle
pure flower
#

chill guys im not being intimidating i love the guy

#

i didnt even say anything 😭

viral lynx
iron kindle
pure flower
#

😭 so rude

#

listen

#

if you're someone who thinks figuring it out yourself in 5 minutes is anything but exemplary, something's wrong with you

#

and i don't think that so

#

chill out

iron kindle
#

if you dont have anything useful to add, just keep it to yourself next time

pure flower
#

*okay but i didnt mean it rudely * 😭

#

i get it though

iron kindle
pure flower
#

parents

devout snowBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

tired oak
#

AK is 13 and i need arc AB

devout snowBOT
distant helm
#

arc AB can be calculated through angle AOB

tired oak
#

but is there any angle?

#

they didnt give any angles

distant helm
#

connect O and K, you can see OK divides the quadrilateral into 2 congruent right triangles

tired oak
#

damnnn

#

ur so smart

distant helm
#

:b

tired oak
#

so degree k and degree o are both 90

#

.close

devout snowBOT
#
Channel closed

Closed by @tired oak

Use .reopen if this was a mistake.

tired oak
# distant helm :b

so it wants major arc ab, i got 47.13 using 3.142 as pi but the answer is 44.54

distant helm
#

lemme see

#

AOK is a right triangle and we already know OA = 10 and AK = 13
so tan(AOK) = 13/10

odd prism
#

ude 22/7

lethal pollen
#

He probably just made an error somewhere

distant helm
#

i wouldnt do approximation midway, i will always find exact value then approximate in the end

#

i also got 44.54 smh

#

u should recheck what u did wrong

lethal pollen
#

Yea me too

#

Even with 3.1412

devout snowBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

distant laurel
devout snowBOT
distant laurel
#

Can somebody help me solve this

keen fulcrum
#

Hihi, I really need help on how to solve the median of a trapezoid 😿

distant laurel
#

is this correct?

winter torrent
#

sure that looks right

distant laurel
winter torrent
#

it's kinda janky because of all the +1 and -1 going on but the logic seems right

distant laurel
#

alright tyyy

devout snowBOT
#

@distant laurel Has your question been resolved?

#
Channel closed

Closed by @distant laurel

Use .reopen if this was a mistake.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

thorny ferry
#

how would i get the first derivative of this if a is a constant

thorny ferry
#

it was written exactly like this so i wasnt sure of if it was arcsin(x/a) + sqareroot a^2+x^2/x or arcsin(x/a + sqareroot a^2+x^2/x)

#

are these derived separately as in arcsin formula + quotient rule? or the whole thing being (u) for arcsin

dense jay
#

i would confidently say its the first case

#

separate terms

pure flower
#

if they're both the argument for arcsin then your instructor needs to get a sense of how brackets are used

devout snowBOT
#

@thorny ferry Has your question been resolved?

thorny ferry
#

actually ill close and just ask for when im done

#

.close

devout snowBOT
#
Channel closed

Closed by @thorny ferry

Use .reopen if this was a mistake.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

thorny ferry
#

is this correct?

devout snowBOT
thorny ferry
#

finding the first dervative

pure flower
#

whats the second term

#

i cant read it

thorny ferry
#

-a^2/x^2squareroot a^2-x^2

devout snowBOT
#

@thorny ferry Has your question been resolved?

thorny ferry
#

<@&286206848099549185>

devout snowBOT
#

@thorny ferry Has your question been resolved?

#
Channel closed

Closed by @thorny ferry

Use .reopen if this was a mistake.

devout snowBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

granite anvil
devout snowBOT
granite anvil
#

how do i do this right

#

I thought this was just sec^2(x) from pi/4

#

so then the integral would js be tanx

blissful igloo
granite anvil
#

why do you have to use u sub tho

#

oh wait

blissful igloo
granite anvil
#

no

#

i was saying tanxsecx = secx 💀💀💀

blissful igloo
granite anvil
#

yeah

#

one sec

restive river
#

have u solved this problem

granite anvil
#

im working on it

#

rn i have integral of u^2

#

i gotta find the boundaries and solve

#

i got 1/3

restive river
#

final answer is 1/3??

granite anvil
#

ye

restive river
#

no

granite anvil
#

thats what the ms says

restive river
#

oh no

#

yes tanQ = t

#

we should replace like this

granite anvil
#

wdym

restive river
#

as u know if tanQ = t, dQ = dt*(cosq)^2

#

right?

granite anvil
#

i said U = tanx

restive river
#

dQ=dt*(cosQ)^2

granite anvil
#

du = sec^2x dx

restive river
#

no

#

if tanQ = t

granite anvil
#

the integrand is (tanxsecx)^2

restive river
#

yes

#

to solve this problem

#

the most important is subtitution

winter patrol
restive river
#

so let tanx = t

#

right?

#

let derivate right and left term

granite anvil
restive river
#

we can get dx = dt*(cosx)^2

granite anvil
#

i dont think thats right

restive river
#

right?

granite anvil
#

shouldn't it be dt/dx = sec^2(t)

restive river
#

yes

#

they are equal

winter patrol
#

sec^2(x), not t

restive river
#

bcz secx = 1/cosx

granite anvil
granite anvil
winter patrol
#

you did fine

granite anvil
#

how is sec^2x = cos^2x

restive river
#

if u solve like this, no matter

granite anvil
restive river
#

where are u located in

granite anvil
#

why

winter patrol
#

Arin's just doing / placing stuff in an unconventional way/location

restive river
#

i am Chicago

#

in

restive river
#

i can give u lots of advice

granite anvil
#

.close

devout snowBOT
#
Channel closed

Closed by @granite anvil

Use .reopen if this was a mistake.

restive river
#

.close

devout snowBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

restive river
#

hi can someone help me with a and b

devout snowBOT
restive river
#

!status

devout snowBOT
#
What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
restive river
#

1

lone ravine
restive river
#

it’s a -2^n

pseudo basin
#

(-1)^n * 2^n

restive river
#

ohh

#

that falls under alternating

#

and for b?

grand warren
#

find an equivalent

restive river
grand warren
#

find an equivalent of the general term in +inf

#

you saw things like $a(n) ~ b(n) \iff \frac{a(n)}{b(n)} \to 1$ ?

restive river
#

no

woven radishBOT
grand warren
#

i would say $3n^6 -1 \approx 3n^6$ for $n \to +\infty$, $5n^8 +1 \approx 5n^8$, and then you can conclude

woven radishBOT
restive river
#

i have to use the ratio test for the first one

#

where would i go from here?

#

@grand warren

grand warren
#

Where did the square root go?

restive river
#

cancelled it

#

sqrt(n) and sqrt(1)

grand warren
#

yeah okay it makes sqrt(1+1/n)

#

so you have $\frac{u_{n+1}}{u_n}=\frac{-2 \sqrt{1+1/n}}{5}$

woven radishBOT
grand warren
restive river
restive river
#

what happened to the 5^n+1/5^n+2

grand warren
#

i simplified it into 1/5 ?

#

$5^{n+1-n-2}=5^{-1}$

woven radishBOT
restive river
#

man im so cooked

#

okay so the answer is -2/5

grand warren
woven radishBOT
grand warren
grand warren
#

so using D’Alembert rule, what can you say about the convergence of the series

restive river
#

converges

grand warren
#

can u explain why

restive river
#

-2/5 is less than 1

grand warren
#

yeah exactly

restive river
#

and for b r u saying to use limit comparison

grand warren
#

no

#

you sure you didn’t saw things like $f \approx g \iff f/g \to 1$ ?

woven radishBOT
restive river
#

oh i have

#

like 1/1.00001

grand warren
restive river
#

,w 1/1.000001

restive river
#

nvm

#

okay but what does that have to do with this

grand warren
#

what’s the limit of $\frac{3n^6-1}{3n^6}$

woven radishBOT
restive river
#

1

grand warren
#

yeah

#

so we can say $3n^6-1 \approx 3n^6$ for $n \to \infty$

woven radishBOT
grand warren
#

do the same with the denominator, find an equivalent

#

Then, make the quotient of the two equivalents

#

and you’ll have the answer

restive river
#

but the radical

grand warren
#

You will have that the general term of the series will be equivalent to $\sqrt{\frac{3n^6}{5n^8}}$

woven radishBOT
grand warren
#

you can simplify this

restive river
#

n^3/n^4

woven radishBOT
grand warren
restive river
#

1/n

grand warren
#

exactly

restive river
#

and that diverges

grand warren
#

yess

#

so using comparison theorem, your series diverges

restive river
#

im so cooked for this midterm

#

i mean its in 2 weeks

#

but this stuff doesn’t make sense to me

grand warren
#

Try to learn the methods to show that a series converges or diverges and it will go by itself

restive river
#

you’re really good at explaining things you should become a teacher

grand warren
#

thank you 🙏🏼

restive river
#

oh lol

#

what kind

grand warren
#

in university

#

in canada maybe it seems cool lol

restive river
#

ah i see well i hope it all goes well

restive river
grand warren
grand warren
restive river
#

that’s fair

#

housing crisises are also pretty unavoidable

#

ig america is one of them that isn’t in one but u pay over 100 for groceries every week 😭

grand warren
restive river
#

literally like a loaf of bread and eggs

grand warren
#

💀💀💀

restive river
#

inflation has gotten so bad here ever since trump went to office

grand warren
#

well, i saw university teacher are rlly good paid lol

restive river
#

yeah they do

#

high school teachers are a different story

#

and below

#

mostly underpaid

grand warren
#

yeah in france too 😅

#

they have a very low salary for what they’re doing

restive river
#

yeah it’s quite sad considering they’re the building blocks of a nation

grand warren
#

ye 😢 with all the taxes idk if they have more than 2k / month lol

restive river
#

right

#

anyways thanks a lot for the help wish you the best!

grand warren
#

np you welcome 😁

restive river
#

.close

devout snowBOT
#
Channel closed

Closed by @dense knot

Use .reopen if this was a mistake.

devout snowBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

lofty verge
devout snowBOT
lofty verge
#

I wrote always but the correct answer is sometimes

#

here is my reasoning

#

If b=4, and a<8, then a is also <64
If b=-4, and a<-8, then a is also <64

#

so can anyone provide a counterexample?

#

this is like transitive property isnt it cus a<x and x<y so a<y

pseudo basin
#

what is the domain of discourse?

lofty verge
#

what is that?

#

this is a competitive algebra 1 test

tired oyster
#

maybe 2b<=4b^2 must always be true for a<2b and a<4b^2

#

try a fraction

lofty verge
#

ahh yep

#

1/2

topaz axle
#

it's always true, maybe it's not in complex numbers

#

ah i see

shell plover
#

One example is a=1/3 and b=1/4
And for it , the equation is not true

lofty verge
#

i guess that makes sense since fractions can only get smaller when squared

#

where i was just assuming squaring makes a number bigger

#

thanks all!

#

.close

devout snowBOT
#
Channel closed

Closed by @lofty verge

Use .reopen if this was a mistake.

shell plover
#

:)

raven leaf
#

I know this is closed

#

But you can't order complex numbers

#

that's to say you can't say $1 > i, 1 < i or 1 = i$

woven radishBOT
#

Xetrov

devout snowBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

verbal mesa
devout snowBOT
verbal mesa
#

any tips for proving this one?

sand dove
#

the other way around

#

if H1 U H2 is a subgroup of G and neither H1 nor H2 is a subset of the other

#

then I can find h1 in H1 but not in H2, and h2 in H2 but not in H1

#

now try to reach a contradiction

verbal mesa
#

okay

#

true

#

so by contradiction is easier?

sand dove
#

here contradiction is the easiest

verbal mesa
#

okay

#

i got it

#

thank you

#

.close

devout snowBOT
#
Channel closed

Closed by @verbal mesa

Use .reopen if this was a mistake.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

wintry musk
devout snowBOT
restive river
#

u can solve this problem by total area of squares...

#

so let the biggest square 's length is x!

#

x-4=x-h so h=4

#

do u understand

devout snowBOT
#

@wintry musk Has your question been resolved?

wintry musk
devout snowBOT
#

@wintry musk Has your question been resolved?

lunar harbor
#

We know that this side must be x-1

#

Similarly, by considering this segment,

#

We know that this must be x-2

#

keep repeating this logic

devout snowBOT
#
Channel closed

Closed due to timeout

Use .reopen if this was a mistake.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

cosmic lodge
#

Want to check if my applied numerical methods hw is right.

For the QR algorithm. Show that if $A$ is symmetric, then so is every $A_k$.

I did

Base case:

$A_1 = Q^{-1}AQ=Q^{-1}A^TQ=A_1^T$

Inductive hyp: $A_k=A^T_k

Inductive step:
$$A_{k+1}=R_kQ_k$$
$$A_{k+1}=Q_k^{-1}AQ_k$$
$$A_{k+1}=Q_k{-1}A^TQ_k$$
$$A_{k+1}=A_{k+1}^T$$

Ik the intended answer but does that work?

cosmic lodge
#

The intended answer would be using the definition of Q being orthonormal, then transposing A_{k+1} to show its equal to itself i think

#

Hm some errors on the typesetting still

woven radishBOT
#

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

cosmic lodge
#

My reasoning is just that they have the same QR factorization

#

.close

devout snowBOT
#
Channel closed

Closed by @cosmic lodge

Use .reopen if this was a mistake.

devout snowBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

ivory umbra
#

need help solving this question step by step, this is for unit 2 of MCV4U, derivatives

lunar vault
# ivory umbra need help solving this question step by step, this is for unit 2 of MCV4U, deriv...

Let x be the horizontal distance from the bow of the boat to the dock.
Let y be the vertical distance from the bow of the boat to the pulley.
Let z be the length of the rope from the bow of the boat to the pulley.
y=1m
dt/dz=−1 m/s
We want to find how fast the boat is approaching the dock, which is dt/dx, when x=5 m
x^2 +1^2 = z^2

d/dt (x^2 + 1) = d/dt (z^2)
chain rule
2x * (dx/dt) + 0 = 2z * (dz/dt)
x * (dx/dt) = z * (dz/dt)

#

from there just substitute

ivory umbra
#

final answer that I got is -5/2 sqrt6 = -1.02m/s

#

is that correct?

lunar vault
#

but u take abs anyway

#

and leave it in fraction form

ivory umbra
#

oh okok

#

sounds good

devout snowBOT
#

@ivory umbra Has your question been resolved?

devout snowBOT
#
Channel closed

Closed due to timeout

Use .reopen if this was a mistake.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

grand haven
#

does A show rotational symmetry? if so, what is the angle of symmetry

grand haven
#

what would the angle of symmetry be for this one?

faint zinc
#

I can help, but we can't just give answers. Can you explain your analysis?

grand haven
#

for which one

faint zinc
#

And then perhaps I can guide you to the conclusion?

#

Whichever one you want to work on first

grand haven
#

idk how to do it so i cant really analyze it

faint zinc
#

So do you know what rotational symmetry is?

grand haven
#

yes

faint zinc
#

Can you explain it to me?

grand haven
#

figure can be mapped onto itself by being rotated less than 360 degrees so that it and the original shape are indistinguishable

faint zinc
#

That is exactly correct

#

Ok so let's take the first one

#

Can this be rotated and mapped back onto itself?

grand haven
#

thats the problem i dont know

faint zinc
#

Ok, so if it can be mapped back onto itself then both of the distinguishing features would map back to themselves right?

#

The nuts and the fin shaped holes

grand haven
#

the book says yes but i dont know how to see it. my teacher only did simple ones and assigns the hard ones he didnt teach for hw

faint zinc
#

How many nuts are there? What about the fins?

grand haven
#

4 nuts 7 fins

faint zinc
#

Ok, so do 4 and 7 share common factors?

grand haven
#

1

faint zinc
#

Yes, so this means that you have to spin it around 360° to get everything lined back up again

#

If it were 2 it would be 180°. In general if there are multiple features then you take the gcd and find 360°/n where n is the gcd

grand haven
#

GCD?

faint zinc
#

Greatest common denominator

grand haven
#

for b i got you cant and for c i got yes, 72 degrees

#

wait if its 360 degrees wouldnt A not have it?

faint zinc
#

That checks out

#

A doesn't, no

grand haven
#

Dam

#

the book says it does

faint zinc
#

The book is mistaken, unfortunately

#

Generally, the person who writes the problems is not the person who writes the answers. And it's easy to miscount 7 as 8

#

And if it's 8 then it has 90° rotational symmetry

grand haven
#

i see

grand haven
faint zinc
#

Sure, this one is easier

grand haven
#

i think its 360

faint zinc
#

Why is that?

#

Would it be possible to rotate it so the arrows map onto themselves?

grand haven
#

it doesnt look the same when i rotate it the other ways

faint zinc
#

It doesn't?

grand haven
#

yeah it doesnt

faint zinc
#

Ok, so, if you've actually manipulated this image the perhaps you know better than I do

#

But I would have thought it was

#

Which part is different?

grand haven
#

lemme try to use a photo editor to rotate it

#

maybe im off

faint zinc
#

Looks pretty much the same to me

#

Maybe there's some very minor spacing differences

grand haven
#

but its not exact

faint zinc
#

Ok, in this case I would answer in this manner:

grand haven
#

i think ima go with its 270 degrees clockwise

#

when i put it on the paper they look the same

faint zinc
#

"Although, this logo seems to have 120° rotational symmetry. Because of minor spacing differences, it is not actually rotationally symmetric."

#

Not 270°

grand haven
#

howd you get 120?

faint zinc
#

360/3

grand haven
#

how do you rotate it 120 degrees with just using ur eyes and hands

faint zinc
#

I just looked at it and imagined it?

grand haven
#

how?

#

i only know how to do 90,180,270,360

#

and thats by rotating the paper

faint zinc
#

Some people have difficulty with visualizing things in their head

#

But 120° is 1/3 of a revolution

grand haven
#

so for ones like those you just divide by the number of arrows and stuff?

faint zinc
#

Yeah

#

The same way you got to 72°

#

For 7c

grand haven
#

i see

#

this shell does not show rotational symmetry because you have to rotate it 360 degrees

#

what about 11 and 12? we didnt learn anything the directions say so ima just do what we’ve been doing the past few @faint zinc

#

for 11 i got yes, 90 degrees

#

for 12 i got yes, always symmetrical

#

or, would 11 be 120 and 12 be 45

#

because of the arrows thing we did

devout snowBOT
#

@grand haven Has your question been resolved?

grand haven
#

<@&286206848099549185>

#

confused on whether its 90 and always OR 120 and 45

devout snowBOT
#

@grand haven Has your question been resolved?

faint zinc
#

Sorry about the delay, I had to go AFK

devout snowBOT
#
Channel closed

Closed by @grand haven

Use .reopen if this was a mistake.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

restive river
#

what does -(-x)*|(-x)^3| become im so confused

restive river
#

someone save me pls 😭

ripe flax
#

theres an absolute value in the -x^3 right

#

hence everything there becomes positive

#

so it turns to x^3

restive river
#

it doesnt i think

ripe flax
#

its an absolute value aint it

restive river
#

bc look at this answer from my quiz

winter patrol
#

abs val doesn't mean remove minus sign

restive river
ripe flax
#

from what i learnt its like how far u travel from 0 to there using the number line

#

so yeah distance has to be positive

winter patrol
#

from abs value laws |-x^3| = |-1| * |x^3| = |x^3|

#

also why were you just focussing on the numertor component

restive river
#

okay wait so what would (-(-x)|(-x)^3|)/((-x)^2+2 be

restive river
winter patrol
#

the x/x, or in that example the a/a, -a/(-a) cancels

#

which reduces the clutter

restive river
winter patrol
#

is that +2 on the end supposed to be part of the denominator?

restive river
#

yes

#

i wish i could draw it out but idk how to use the bot lol

winter patrol
#

using sufficient parentheses is good enough for me

#

or you could use something like desmos to mathematically type it

#

or draw it in paint

#

$\frac{-(-x) |(-x)^3|}{(-x)^2+2}$

#

that?

restive river
#

wait no theres an extra ^3 in that image

#

its outside of the parenthesis

winter patrol
#

sry

woven radishBOT
#

ℝαμOmeganato5

restive river
#

yes!!

#

okay what happens here 😭

winter patrol
#

dw about the abs value bars for now,
would you be able to simplify the other components with ()

#

$\frac{\blue{-(-x)} |\violet{(-x)^3}|}{\red{(-x)^2+2}}$

woven radishBOT
#

ℝαμOmeganato5

winter patrol
#

first simplify each colour

restive river
#

mhm mhm i got that far

#

but its this silly business w/ the absolute value thats messing with me

winter patrol
#

what do you have atm

restive river
#

(x|-x^3|)/(x^2+2)

winter patrol
#

apply
$$|ab| = |a||b|$$
note: $-x^3 = -1 \cdot x^3$

woven radishBOT
#

ℝαμOmeganato5

restive river
#

okayyyy so id have x|-1||x^3| on the numerator right

winter patrol
#

yes, and simplify that further

winter patrol
ripe flax
#

but after putting the absolute value

#

anything in there becomes positive regardless of what x is

#

like |x^3| where x=-3

#

it becomes |-27| but it evaluates to 27

restive river
winter patrol
#

|-1| = ?

ripe flax
#

take vectors for instance, AB = -27i, the magnitude AKA |AB| = 27

ripe flax
winter patrol
#

NOT U

restive river
#

okay wait so it would just turn into x|x^3| right

winter patrol
#

yes

restive river
#

and you cant simplify further right?

winter patrol
winter patrol
#

ok, like i said that's wrong then

#

with x=-3, you'll get 27 on the left side but -27 on the right side

ripe flax
#

do u mean i have to examine 2 cases

#

like if x is positive and x is negative

winter patrol
#

if you want to express that without abs values, you'd need cases

#

which is tedious, makes it look more complicated
so just leave it as is (unless you need to do it for another goal)

restive river
#

why doesnt it turn into -x-|x^3|

winter patrol
#

why do you think it should turn into -x-|x^3|

#

what laws are you applying

restive river
#

(-1)x (-1)|x^3|

winter patrol
#

not what you typed,
regardless still wrong

#

multiplication doesn't distribute over multiplication

#

$2 \times (3 \times 4) \redneq 2\times 3 \times 2 \times 4$

woven radishBOT
#

ℝαμOmeganato5

devout snowBOT
#

@restive river Has your question been resolved?

restive river
devout snowBOT
#
Channel closed

Closed by @stiff sparrow

Use .reopen if this was a mistake.

restive river
#

.reopen

devout snowBOT
#

restive river
#

ok we're back

#

😔

#

😔how would i find the symmetry of this

severe bolt
restive river
#

ermmm i dont know 🌹

#

symmetry over y axis or origin

severe bolt
#

Do u want to draw it?

#

Or to calcul it

restive river
#

calculate it

#

graphing isnt allowed

severe bolt
#

Your educational level is higher than mine

#

I just noticed

restive river
#

its only precalc so youre probably still ahead of me

severe bolt
#

Do u remember

#

$f(x) = f(-x)$

woven radishBOT
#

╰ 𝕃 𝕌 ℂ 𝕀 𝔽 𝔼 ℝ ╮

restive river
#

mhm

severe bolt
restive river
#

yeah

severe bolt
#

That's it

restive river
#

theres more to it

#

its |y| =

severe bolt
#

If f(x) = f(-x) that means the function is symmetric by y axis

restive river
#

its not f(x) =
its |f(x)|

severe bolt
severe bolt
restive river
#

Now im confused again 🥀

restive river
severe bolt
#

I showed u ur way

restive river
#

😭 you showed me the part that i already know

#

how do i deal with the absolute value

severe bolt
#

Can't u cancel it?

#

x² + 2 >0

restive river
#

i have no idea

severe bolt
#

For ]-inf;0]: x <0

#

y remains itself

#

For [0; +inf[: x > 0

#

U need to multiply by -

#

So y could be positive

#

That's justly symmetric...

restive river
#

symmetric over what

#

origin or y axis?

severe bolt
#

Y

#

I found out that | | doesnt change the symmetrically

#

if f(x) = f(-x)
Then |f(x)| = |f(-x)|

restive river
#

its not symmetric over origin or y axis

severe bolt
#

That's why not symmetric

devout snowBOT
#

@restive river Has your question been resolved?

#
Channel closed

Closed by @stiff sparrow

Use .reopen if this was a mistake.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

restive river
#

hi guess whos back >.<

devout snowBOT
restive river
#

is there an easy way to do this

graceful cosmos
#

Not really haha

#

Graph it

#

Graphing it isn't too hard with transformations in mind

restive river
#

we arent allowed graphing calculators

#

😭

graceful cosmos
#

I wasn't suggesting using a calculator

restive river
#

fml

#

LMAO

#

which points should i focus on?

#

or like how do i do it in the fewest possible points

graceful cosmos
#

|x - 4| is like |x|, but shifted right by 4

restive river
#

my prof didnt graph it but i cant make sense of what he did

graceful cosmos
#

Ah that's a cool way to do it

#

|u| = u, if u is positive
|u| = -u, if u is negative

#

So they check the signs for
x < 0,
0 < x < 4, and
x > 4

restive river
#

OH so i just have to plug in a few numbers?

#

i actually dont understand absolute values theyre killing me

neat oar
#

that is just playing with the inequality

graceful cosmos
#

So as an example, if 0 < x < 4
x is positive, so |x| = x
x - 4 is negative, so |x - 4| = -(x - 4)

neat oar
#

not random plug in number

graceful cosmos
#

So |x - 4| - |x| = -(x - 4) - (x)

restive river
#

i wish i understood LMAO

#

ty though!!

graceful cosmos
#

Alright good luck!

restive river
#

💚

#

wait wait

#

how is -infinty,0 possible for a one to one function

#

@graceful cosmos

neat oar
#

why not

graceful cosmos
#

Like, how is such a domain possible? I don't see why not

neat oar
#

one to one function mean theres only one input corresponding to one output ONLY

#

-infinity just mean no limit, can go to as small as you want

restive river
#

i mean its not one to one it fails the horizontal line test

neat oar
#

in that region it satisfy the test

#

should be

restive river
#

it doesnt

neat oar
#

hmm what

graceful cosmos
#

Then their answer is wrong!

restive river
graceful cosmos
#

Do you see the largest domain that would give a one-to-one function?

restive river
#

yeah it should be 0,4

#

right?

neat oar
#

yeah i think should be opposite

graceful cosmos
#

Yeah that looks like it to me

neat oar
#

[0,4] is the correct interval if u want it to be one to one function

restive river
#

oki ty at least i know im not insane

graceful cosmos
#

,w graph |x - 4|, |x|, |x - 4| - |x| between -10 and 10

fallen oak
#

Not trying to budge in yalls session but have either of you taken college stat recently/ enought to know what i should be doing?

restive river
#

Nope 🥀

graceful cosmos
restive river
#

im taking it next semester

fallen oak
graceful cosmos
# woven radish

This is my "graph it" strat. Yellow and blue should be easy graphs to make, but green might be trickier to see

winter torrent
#

you can also just kinda think about "well what happens if x is really big" because then x-4 is positive and so is x

#

so your thing becomes (x - 4) - x

restive river
#

that kinda makes sense but i think the problem is that i fundamentally dont understand absolute values 😭

#

who decided to add if/else statements to algebra

devout snowBOT
#

@restive river Has your question been resolved?

devout snowBOT
#
Channel closed

Closed due to timeout

Use .reopen if this was a mistake.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

fading hollow
devout snowBOT
fading hollow
#

Part b please

#

Is the solution (4-p)/3 or (1+p)/6

devout snowBOT
#

@fading hollow Has your question been resolved?

fading hollow
#

<@&286206848099549185>

#

. close

#

.closed

#

.close

devout snowBOT
#
Channel closed

Closed by @fading hollow

Use .reopen if this was a mistake.

devout snowBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

tall summit
devout snowBOT
tall summit
#

i know im suppose to complete the square.... but this is a technique i never used since forever.....

devout snowBOT
#

@tall summit Has your question been resolved?

tall summit
#

.close

devout snowBOT
#
Channel closed

Closed by @tall summit

Use .reopen if this was a mistake.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

#
Channel closed

Channel closed due to the original message being deleted.
If you did not intend to do this, please open a new help channel,
as this action is irreversible, and this channel may abruptly lock.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

normal bolt
#

I want to undertand these questions fundamentally. I don't want their answers but to understand concept behind then fundamentally so i can apply to any question. If anyone could explain this stuff?

Q. Find the domain and range of the following real functions:
(i) f(x) = - |x|
(ii) f(x) = √(9 - x^2)

Definitions ⏬

A function which has either R or one of its subsets as its range is called
a real valued function. Further, if its domain is also either R or a subset of R, it is
called a real function

A relation f from a set A to a set B is said to be a function if every
element of set A has one and only one image in set B.

In other words, a function f is a relation from a non-empty set A to a non-empty set B such that the domain of f is A and no two distinct ordered pairs in f have the same first element.

If f is a function from A to B and (a, b) ∈ f, then f (a) = b, where b is called the
image of a under f and a is called the preimage of b under f.

lime plaza
#

Uh so domain is what all values we can enter for x so f(x) is defined

#

Range will be the outputs which you get for entering values from domain

#

Use that to solve?

normal bolt
#

let me try tosolve

lime plaza
normal bolt
lime plaza
#

Ok

#

Put brackets then

#

Ok solve then

normal bolt
#

(i)
domain = set of all real numbers
range = set of all real numbers

(ii)
domain = set of all real numbers
range = set of all real numbers

lime plaza
#

uh no

#

So for (i) domain is set of all real numbers ok

#

But now ur range is wrong

normal bolt
#

y

lime plaza
#

Choose 3 numbers

#

From domain

#

choose a -ve choose 0 and choose positive

normal bolt
#

7, - 2 , 15

lime plaza
#

Put x= that

#

And see what you get

normal bolt
#

7 , 2 and 15

lime plaza
#

uh u sure?

#

f(x)= -|x|

normal bolt
#

modulus function change every value to positive

#

doesn't matter if there is - sign before

lime plaza
#

f(x)= - |x|

normal bolt
#

-7, -2, -15, but i dont think -ve sign matters since it is a modulus function

lime plaza
#

That's where you are wrong

#

It doesn't matter inside modulus

#

The negative sign is outside the modulus

#

So if I tell you x= -3

#

What is |x|

normal bolt
#

3

lime plaza
#

ok but now

#

there is a - |x|

#

So we know |x|=3

#

Just put -ve before that

normal bolt
#

-3

lime plaza
#

Yes

normal bolt
#

why does it happens?

lime plaza
#

Negative becomes positive only inside the modulus

#

Modulus is defined that way

lime plaza
#

But always try 0

#

To check if 0 is included or not

normal bolt
lime plaza
#

no

#

Like for any number you enter

#

You get negative values right?

normal bolt
#

yes

lime plaza
#

for f(x)= - x

#

Ok so now try 0

#

what do u get

normal bolt
#

0

lime plaza
#

ok so 0 is included

#

now are you getting any positive values

normal bolt
#

no

lime plaza
#

for any number

#

Ok so positive can never be the output

normal bolt
#

yup

lime plaza
#

So all negative numbers and 0 is the output do you agree?

normal bolt
#

but the domain is set of all real numbers

lime plaza
#

Yes

#

Enter any number you can think of

normal bolt
#

it should be integers rather

lime plaza
#

enter a real number then

#

Just check the range

normal bolt
#

f(9) = -9

lime plaza
#

It will never be positive

#

Ok now f(x)= - x

#

Yep

#

see

#

so it's always negative

normal bolt
#

but for 0 it is 0

#

not -0

lime plaza
#

Yes

#

That means

#

0 is also included

#

In output

#

0 is neither positve nor negative

#

That is why always check zero

#

To check range choose a -ve number choose a +ve number and choose 0

normal bolt
#

but in real numbers we are only talking abut -ve nums. Here 0 is not -ve not +ve

lime plaza
#

Huh

#

We get 0 as output

#

DOMAIN is real numbers

#

We are trying to find range

#

So enter different values of domain and see what we will NOT get

normal bolt
#

range will include 0 and all negative nums?

lime plaza
#

That's it

#

Do you know how to write it?

normal bolt
#

no