#help-4

1 messages · Page 22 of 1

glass kelp
#

,rccw

rocky lotusBOT
glass kelp
#

how did we get here

maiden panther
#

Tanx/2 substitution and partial fraction decomposition

#

I probably did it wrong tho

#

Here

heady pawn
maiden panther
heady pawn
#

it gives all the steps and substitutions

astral spoke
timber swan
#

Uhh

maiden panther
glass kelp
#

id do u = pi/2 - x first

astral spoke
#

no way bro.... anyways good luck with the maths, I'm not good enough to help but you got this

glass kelp
#

then t = 1 - sinu

maiden panther
#

Appreciate it

maiden panther
dire cloud
#

Can't you substitute 1-cosx=t and get everything in terms of t

timber swan
heady pawn
#

expand

#

use u = cos(x) - 1

timber swan
#

Theres a really trivial way of doing this

maiden panther
heady pawn
#

then use u = tan(x/2)

#

GL

maiden panther
#

Aight

heady pawn
#

you can see the steps

dire cloud
#

I can figure out substitutions but idk integration

glass kelp
#

Using ${u = \frac{\pi}{2} - x}$, ${\dd u = -\dd x}$. So,
[ -\int_{0}^{\pi/2} \frac{1-\sin(\pi/2 - x)}{1 - \cos(\pi/2-x) \dd u} = -\int_{0}^{\pi/2} \frac{1-\cos(u)}{1-\sin(u)}\dd u ]

rocky lotusBOT
glass kelp
#

Then, let $t = 1-\sin(u)$

rocky lotusBOT
glass kelp
#

should get a simple 1/t

maiden panther
#

Hmm let me do that

timber swan
#

Hmm

dire cloud
maiden panther
#

Im restarted

#

I didn't get it

maiden panther
#

Let me try again

glass kelp
#

sub u first, then sub t

timber swan
#

Idk why all this is neededKEK

glass kelp
heady pawn
#

kings rule?

timber swan
#

U could just break it into two very easy integrals

#

😩

maiden panther
#

Oh hell nah how do I do this

dire cloud
#

Yeah that's what I'm trying

timber swan
#

1/1-cos

glass kelp
#

oh i see

timber swan
#

Sin/1-cos

timber swan
dire cloud
heady pawn
#

yeah That's what hthey're doing right

dire cloud
#

Wait I forgot to crop

timber swan
#

As u can just convert to cosec

dire cloud
#

Ignore the physics on top

heady pawn
#

1 is easy and the other one is annoying

glass kelp
#

i think sub is faster tho

timber swan
#

Both are easy

heady pawn
#

Keep smellin ur own farts bro

#

anyways

dire cloud
timber swan
maiden panther
heady pawn
heady pawn
#

🥀

glass kelp
#

anyhow

#

back to the op

maiden panther
#

Yessir

glass kelp
#

progress?

maiden panther
#

Im not getting shi

dire cloud
maiden panther
#

Im so bad at integration

glass kelp
#

sub u = pi/2 - x first

#

Using ${u = \frac{\pi}{2} - x}$, ${\dd u = -\dd x}$. So,
[ -\int_{0}^{-\pi/2} \frac{1-\sin(\pi/2 - x)}{1 - \cos(\pi/2-x)} \dd u = \int_{-pi/2}^{0} \frac{1-\cos(u)}{1-\sin(u)}\dd u ]

timber swan
#

||1/1-cos can just be converted to cosec^2(x/2)||

glass kelp
#

are u following this

maiden panther
#

How did

#

Limits change

rocky lotusBOT
timber swan
glass kelp
#

when u do a substitution the bound change

dire cloud
#

ok I'm just gonna go then 🥀

glass kelp
timber swan
glass kelp
#

but works

maiden panther
#

Why zero tho

timber swan
#

💔

timber swan
glass kelp
glass kelp
timber swan
#

So yes

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Its trivial

#

🗣️🗣️

heady pawn
#

lol

maiden panther
#

Now but why did you substract pi/2

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Normally when making substitution do we change limits too?

timber swan
#

Yes

maiden panther
#

Damn bruh nvm yeah

maiden panther
#

When I use another substitution will the limit change again?

timber swan
#

😔

glass kelp
#

Let ${t = 1-\sin(u)}$. So ${\dd t = -\cos(u) \dd u }$

glass kelp
#

thats the way my brain works

#

i have bias against trig

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like childhood trauma

maiden panther
#

So what will it change to?

glass kelp
maiden panther
glass kelp
#

[ \int_{0}^{1} \frac{1}{u}\dd u ]

rocky lotusBOT
maiden panther
#

I see

glass kelp
#

which is poggers

timber swan
#

🗣️🗣️

maiden panther
#

Indeed

#

Alright I'll try it

#

Thanks for the help

#

.close

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#
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glass kelp
#

ive realized i make a mistake

vale dockBOT
glass kelp
#

Using ${u = \frac{\pi}{2} - x}$, ${\dd u = -\dd x}$. So,
[ -\int_{0}^{-\pi/2} \frac{1-\sin(\pi/2 - x)}{1 - \cos(\pi/2-x)} \dd u = \int_{-\pi/2}^{0} \frac{1-\cos(u)}{1-\sin(u)}\dd u ]

rocky lotusBOT
glass kelp
#

i made a mistake

maiden panther
#

Grahh

#

.open

glass kelp
#

its open

#

thats why one shouldnt integration in their head

maiden panther
#

1-sinu differentiation

glass kelp
#

anyhow

maiden panther
#

Won't give

#

Numerator

glass kelp
#

yes

maiden panther
#

1 is gone

glass kelp
#

that was the mistake

maiden panther
#

Ok so now what

glass kelp
#

[ \int \frac{1}{1-\cos(x)} \dd x - \int \frac{\sin x}{1-\cos(x)}\dd x]

rocky lotusBOT
maiden panther
#

Got it

glass kelp
#

right one is trivial u = 1-cos(x)

maiden panther
#

Don't look that trivial to my dum ahh😭🙏

glass kelp
maiden panther
#

Oh yes

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I get the right one

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Bet let me try that

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By the way it's sinin denominator

glass kelp
#

?

maiden panther
glass kelp
#

ignore the former subs

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i thought pi/2 -x would work out nicely

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my apologies

maiden panther
#

Oh forget the previous ones?

glass kelp
#

ye

maiden panther
#

Alright got it

glass kelp
#

$ \cos^2x + \sin^2 x = 1$ and $\cos^2 x - \sin^2 x = \cos(2x)$. Adding both sides yields $2\cos^2 x = + \cos(2x)$. So, ${2\cos^2 x - 1 = \cos(2x)}$. Thus, ${1 - 2\cos^2(x) = -\cos(2x) = 2 - 2\cos^2(x) = 1-\cos(2x)}$. Therefore, ${2\sin^2\left( \frac{x}{2} \right) = 1 - \cos(x)}$

maiden panther
#

We get cosec square x/2 divided by 2

#

How does that help

glass kelp
#

LHS becomes
[ \frac{1}{2}\int \sec^2\left(\frac{x}{2}\right) \dd x]

rocky lotusBOT
glass kelp
maiden panther
#

No it's cosec look

glass kelp
#

i derived it

maiden panther
#

So

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Cosx = 1-2sin square x/2

glass kelp
#

OH SHIT

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the negative sign

maiden panther
#

So 1-cosx becomes 2sin square x by 2

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Oh yeah integration cosec square is just cot

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Minus cot

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Thanks a lot

#

Got it

#

.close

rocky lotusBOT
glass kelp
#

.close

vale dockBOT
#
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glass kelp
#

@maiden panther Once again srry

#

🙏

#

ill be off discord now

maiden panther
#

Oh hell nah why sorry

#

You was the most helpful

#

.close

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terse chasm
#

what happens between the last and the penultimate step?

viscid spade
#

Factor out the fraction (y2-y1)/(x2-x1)

terse chasm
#

could you help me through that? factorization is unintuitive for me with fractions

viscid spade
#

If you let Z= fraction does it seems more natural?

stark wedge
#

^

#

with the abbreviation yaku suggested, the step becomes:

$zx + (y_2 - zx_2) = z(x-x_2) + y_2$

rocky lotusBOT
terse chasm
#

oh i can see

viscid spade
#

Also you can write without the parentheses for the first one if it helps

terse chasm
#

yes that is very useful

#

thanks

viscid spade
#

Do it each time then ! One day you won't need to anymore

terse chasm
#

i think i will take it from here

#

thanks for the advice

#

!close

viscid spade
#

.

terse chasm
#

whats the command again?ç

viscid spade
#

!done

vale dockBOT
#

If you are done with this channel, please mark your problem as solved by typing .close

terse chasm
#

!done

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If you are done with this channel, please mark your problem as solved by typing .close

terse chasm
#

.close

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hearty fern
#
  1. Determine and in such that and

\text{lcm}(a, b) - \gcd(a, b) = 7

  1. Determine and in (the set of positive natural numbers) such that

2 \cdot \text{lcm}(a, b) - 7 \cdot \gcd(a, b) = 11

  1. Determine and in such that and

\text{lcm}(a, b) - 3 \cdot \gcd(a, b) = 4

hearty fern
#

Need help plz

glass kelp
#

holy

#

$\text{lcm}(a, b) - \gcd(a, b) = 7$

rocky lotusBOT
dusk stirrup
hearty fern
#

Here's the original it's in french so I tried to translate it

glass kelp
#

what is that notation

#

anyhow

#

i would consider prime factorisation of a and b

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(not sure if its the right approach tho)

hearty fern
#

Already tried that but didn't work

glass kelp
#

8 and 1 are prolly trivial soln

#

hmm i dont know much no. theory

#

i will double it and give it to the next helper

hearty fern
#

<@&286206848099549185>

stark wedge
#

gcd and lcm are both divisible by the gcd, and therefore so is their difference

#

so gcd(a,b) divides 7

hearty fern
#

Thank you ☺️

glass kelp
#

$2 \cdot \text{lcm}(a, b) - 7 \cdot \gcd(a, b) = 11$

rocky lotusBOT
hearty fern
stark wedge
#

two cases then

#

if gcd=1 then lcm has to be 8

#

therefore the product of your two numbers is 8

hearty fern
#

Ah ok I got it from here

#

Thanks

#

.close

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#
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worldly prawn
#

Use the functions provided to solve each of the following. Let the region R be the area bounded above by f(x) and bounded below by g(x) in quadrant I. Write, but do not solve, an integral expression that can be used to find the volume of the solid generated when region R is rotated about the y-axis.

f(x) = 4-x^2
g(x) = x+2

I keep getting conflicting results whenever I do it, and some help would be appreciated

stark wedge
#

show your latest attempt

#

also show your graph if any

#

if you don't have a graph then you should make one

worldly prawn
#

alr ill send that

#

basically waht i did is

f(x) = 4-x^2
g(x) = x+2

so

sqrt{4-y} = x
y-2 = x

Then, washer method, but i dont know what to use as my bounds....

red tulip
#

i think its easier to use cylinders

#

instead of putting it in terms of y

stark wedge
#

shells are easier yeah

half wind
half wind
#

Hes required to use disk and washer method apparently

stark wedge
worldly prawn
#

nah shes one of my friends

#

its for AB

#

so we cant use shell

stark wedge
half wind
stark wedge
#

bruh

worldly prawn
#

yup

stark wedge
#

ok well do yall have a graph though

half wind
worldly prawn
#

alr

red tulip
worldly prawn
#

so we just use that section

#

heres a graph i spun up

#

i have a paper one but unfortunately no way to photograph it rn

red tulip
#

wait actually

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in this case its a sqrt function

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so you would only get the top part

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nvm

worldly prawn
#

\int_{2}^{4}\pi\left(\left(y-2\right)^{2}-\left(\sqrt{4-y}\right)^{2}\right)dy

.latex

#

sry is there a way to render latex?

#

this is the solution i got so far

#

i just need help w finding the bounds im pretty sure its 2->4 and then when i rewrote the functions i jst chose the one on top to be the first function and then the one on the bottom to be the subtractant but im not 100% sure abt that as well

red tulip
#

if you translate everything into being in terms of revolving around the x axis it might be easier

worldly prawn
#

true...

#

so take the inverse of each function?

stark wedge
#

if shell is banned you need two integrals

#

i think

worldly prawn
#

wait whys that?

red tulip
stark wedge
red tulip
#

no wait what if you just take the integral from 2 to 3 for the x+2 function and from 3 to 4 for the quadratic function

#

and add them together

stark wedge
#

you have to split the solid into the revolution of the green stuff and that of the purple stuff

red tulip
worldly prawn
#

ohh

#

alr i see: since what curve is on top changes

#

,help

rocky lotusBOT
#

A brief description and guide on how to use me was sent to your DMs!
Please use ,list to see a list of all my commands, and ,help cmd to get detailed help on a command!

worldly prawn
#

so if i do that then i should get

\int{3}^{4}\pi\left(\left(y-2\right)^{2}-\left(\sqrt{4-y}\right)^{2}\right)dy+\int{2}^{3}\pi\left(\left(\sqrt{4-y}\right)^{2}+\left(y-2\right)^{2}\right)dy

,tex

#

this essentially

red tulip
#

just take the individual integrals of each function and add them

worldly prawn
#

ohh so i can integrate over 2->4 for both of them and then sum those?

#

wait that doesnt quite make sense i think i misunderstood u

red tulip
#

no only 3 to 4 for the quadratic and 2 to 3 for the linear

stark wedge
#

just pi(y-2)^2 and pi(sqrt(4-y))^2

worldly prawn
#

okay i got what you mean

#

so then i get 23/6 * pi

#

like this

red tulip
worldly prawn
#

A;R

#

alr

#

wait but dont we want 2->3 for the linear (4-y) and 3->4 for the quadratic?

red tulip
worldly prawn
#

alr then we get 5pi/6 which is far more reasonable

#

thank you so much!

vale dockBOT
#

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scarlet sandal
#

I don't understand how the author could combine the limits (subtly)

scarlet sandal
#

The two subtracting log terms put in one expression implies that the limits were combined, but I thought you can only combine the sum of two limits if both of them exist, which in this case is false

#

but the author's goal is to justify that $\int_0^{\infty} \frac{1}{x^3-1} dx$ is convergent

rocky lotusBOT
scarlet sandal
#

here's the content immediately before and after the pinned screenshot

vale dockBOT
#

@scarlet sandal Has your question been resolved?

scarlet sandal
#

<@&286206848099549185>

vale dockBOT
#

@scarlet sandal Has your question been resolved?

scarlet sandal
#

(i'm headed to sleep now please don't close the channel automatically ;-;)

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.close

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haughty jackal
vale dockBOT
last shuttle
#

pa solve guys

haughty jackal
#

Did I form the equation correctly? If so, how do I compute this? What does it even mean for the power of a matrix to approach infinity?

last shuttle
#

help to solve this problem 😢

junior jay
vale dockBOT
# last shuttle

Someone else is already using this help channel. If you need help with a question, please open your own help channel/thread (see #❓how-to-get-help for instructions).

dapper dagger
#

however, the entries of A^n are not just the n'th powers of entries of A, so that's a bit of a drag

haughty jackal
dapper dagger
#

well, if it was diagonalizable, that'd be cool

haughty jackal
#

What does it mean to be diagonalizable

dapper dagger
#

firstly, have you encountered diagonal matrices?

#

they're just (square) matrices in which every entry that is not on the main diagonal is 0

#

for a square matrix A to be diagonalizable, there must be an invertible matrix P and some diagonal matrix D so that A = P^(-1)DP

#

it's a really nice trick if you know it; power series become much nicer. for instance,

A^2 = AA = (P^-1DP)(P^-1DP) = P^-1DDP = P^-1D^2P

haughty jackal
dapper dagger
#

consequently, A^n = P^(-1)D^nP (why?)

rocky lotusBOT
dapper dagger
#

that's what I wrote, yeah

haughty jackal
#

Yes

dapper dagger
#

it makes limits involving A^n's nicer

#

so that's the appeal

haughty jackal
#

Time to learn diagonalization

#

Thanks

dapper dagger
#

yee

haughty jackal
#

.close

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#
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vale dockBOT
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old finch
#

Can someone tutor in me in pre algebra

vale dockBOT
old finch
#

I know nothing

#

And I would like if we are vc

tidal terrace
old finch
#

So no one will actually tutor

#

Me

junior jay
#

Well it's just not really the point of this server, at least not the help channels. You might be able to find someone still, but with the ressources available on the internet you can go a long way

old finch
#

Ok recommend any

tidal terrace
old finch
#

The thing is I just get so unfocused when doing stuff alone

vale dockBOT
#

@old finch Has your question been resolved?

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sharp harness
#

Hi guys i need help with solving these questions

sharp harness
#

I solved a and b

#

But I don’t understand c and d

mystic harness
#

How many solutions if:
x1 = 0?
x1 = 1?
x1 = 2?
...

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#

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copper willow
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copper willow
#

<@&286206848099549185>

vale dockBOT
tidal terrace
vale dockBOT
# copper willow <@&286206848099549185>
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
copper willow
#

OMG SORRY I JUST FIGURED IT OUT

#

i need some sleep

tidal terrace
#

yeah ?

copper willow
#

im at a place where i keep getting stuck everywhere

#

the first one is just 6n cuz i thought it was like all cells in all circles

#

omg

tidal terrace
copper willow
#

in the second one tho only right

#

i mean part b

tidal terrace
copper willow
#

is there a formula needed for part b tho

tidal terrace
wraith heart
vale dockBOT
# copper willow <@&286206848099549185>

Please only use the <@&286206848099549185> ping once if your question has not been answered for 15 minutes. Please do not ping or DM individual users about your question.

copper willow
#

and question b is asking for total honeycombs

slate basin
#

Is it 1 + 6 ( summation 1 to n)

tidal terrace
copper willow
#

but i tested and 6n works for both rings

#

and the next one

#

oh also for part b will i need to do 6n for every ring then add the initial or is there another formula

#

if anyone knows if i need to do 6n for every number up to 9 and add them up let me know

#

thanks

#

im in grade ten taking grade 11 functions right now in the YRDSB school board btw if any of yall had somethin different

stark wedge
#

there are several ways to calculate this

#

do you know how to do any of the following?

  • find the sum of the first n natural numbers, i.e. 1+2+...+n
  • find the sum of an AP given its first term, term count, and common difference
vale dockBOT
#

@copper willow Has your question been resolved?

vale dockBOT
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drowsy atlas
vale dockBOT
drowsy atlas
#

what did I do wrong bruh

glass kelp
drowsy atlas
#

Is the answer not C and E

#

hi @glass kelp lol

#

you’re always here

glass kelp
#

v'(t) is the acceleration

#

not velocity

drowsy atlas
#

does any of the answers I chose contradict that

glass kelp
#

the graph of v'(t) isnt D

drowsy atlas
#

wait

#

Oh

#

I’m so blind

drowsy atlas
#

Did I do smth wrong there too

glass kelp
#

its small

#

firstly

#

lets decide what is the correct of v'(t)

drowsy atlas
#

Oh

#

B?

glass kelp
#

ye

drowsy atlas
#

nice

odd jackal
#

I thought cat was @primal crest opencry

glass kelp
drowsy atlas
#

is D vt graph

#

Cuz I use D to find B

glass kelp
#

how abt F

drowsy atlas
#

wdym F

#

F as VT?

odd jackal
#

Is this a test?

drowsy atlas
glass kelp
glass kelp
drowsy atlas
#

imagine having online tests 🔥🔥🔥

glass kelp
#

why is it wrong

drowsy atlas
#

oh

glass kelp
drowsy atlas
#

it’s only slowing down if

#

VT and V’T are opposite signs

#

if they’re the same sign

#

It speeds up

#

Or else im teipoinf

#

teipoinf

#

trooping

glass kelp
#

is there any point where VT is negative

drowsy atlas
drowsy atlas
#

but

#

it was talking abt the graph given?

glass kelp
#

so is there any instance that when v'(t) is negative it causes v(t) to increase in magnitude

drowsy atlas
#

yea

#

only when v(t) is also negative

glass kelp
green urchin
#

hi

glass kelp
#

hello

drowsy atlas
#

im so confused

green urchin
#

where are you stuck at

drowsy atlas
#

based on the statement F I thought it’s saying

green urchin
#

drop it

glass kelp
drowsy atlas
#

Car is always slowing down if v’(t) is negative

green urchin
#

v' is acceleration, so when it's negative, it indicates retardation

#

So its slowing down

#

that is, F is korecht

drowsy atlas
#

korecht

#

ok

green urchin
#

real

drowsy atlas
#

L wording

glass kelp
#

i mean

green urchin
#

its always korecht or inkorecht

glass kelp
#

this is true since there is no instance where v(t) is negative catshrug

#

is the point im trying to convey

drowsy atlas
#

ok ty guys

#

Where’s your pfp from @green urchin

green urchin
drowsy atlas
#

sick

green urchin
#

you can read tbate aswell its good

vale dockBOT
#

@drowsy atlas Has your question been resolved?

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floral lily
#

An acquaintance of mine needs help with this, and since i’m an english major I have no clue how to solve it 😭

marsh forge
#

similar triangles

floral lily
#

Could you explain?

#

DE = BC or is it like 1/3 of BC? I’m trying to recall some rules but idk..

marsh forge
floral lily
nocturne flower
#

hey! i can help you with this

marsh forge
#

similarity between two triangles just mean two triangles have the same shape, not necessarily the same size

floral lily
marsh forge
#

and also the ratio between two corresponding sides are equal

floral lily
#

Taking AE = x
EC = 4.8 - x

In ABC =>
DE || BC

Therefore, using BPT (Thales Theorem)
AD:DB = AE:EC

Putting in values
3x:5x = x:4.8-x

Therefore, x = 9/5 = 1.8

#

Something something

floral lily
floral lily
marsh forge
floral lily
marsh forge
#

its just similarity

marsh forge
#

let AD = 3x, DB = 5x and by similarity we should have AD/AB = AD/(AD + AB) = 3/8

#

then the "scale factor" of ADE wrt to ABC is 3/8

nocturne flower
#

use the basic proportionality theorem

#

that is AD= 3X DB=5X

marsh forge
#

wait is DE even findable

manic hatch
#

You just find it via similarity?

marsh forge
#

they gave AC

nocturne flower
#

then AB= AD +DB = 3X+5X=8X

marsh forge
#

;-;

manic hatch
#

Ah, I messed the drawing up

marsh forge
#

so cant you just vary DE

#

sighh

manic hatch
#

But still, similarity?

marsh forge
#

by similarity you can only deduce AE,EC

#

maybe i suck

nocturne flower
#

use the ratio now to find DE

vale dockBOT
#

@floral lily Has your question been resolved?

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fluid pecan
vale dockBOT
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fluid pecan
#

Oh shit

safe fulcrum
#

why did you close?

stark wedge
#

yeah just go take a new channel

timber swan
#

Do division

fluid pecan
#

The remix was messed up srry

vale dockBOT
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rare ridge
#

in a mapping diagram, does a many-to-many relationship exist? 😭

quick rose
#

well sure whats the problem

#

why wouldnt it exist

rare ridge
#

can i get a visual to what it looks like

#

just wanna check i didnt get it mixed up

lyric sundial
#

!original

vale dockBOT
#

Please show the original problem, exactly as it was stated to you, with the entire original context. A picture or screenshot is best. If the original problem is not in English, then post it anyway! The additional context might still be helpful. Do your best to provide a translation.

deep cedar
#

hello

stark wedge
# deep cedar hello

hello, welcome to the server. this channel is currently occupied by someone else (ie has someone else's name on it)

deep cedar
#

oh mb didnt notice

rare ridge
#

i think i got it now, thank youu

#

.close

vale dockBOT
#
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vale dockBOT
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north scarab
#

how do i solve this first quesiton

vale dockBOT
north scarab
#

dont tell me the answer

#

i know that this is repciprcal function of cos(theta)

#

it gave me an undefined answer

#

defintely messed up this question

sick sparrow
#

you forgot to divide by 1.8939 to isolate cosβ

north scarab
#

which line

sick sparrow
#

the last one

#

for some reason you included it inside the cosine operator

north scarab
#

u mean the second last line

sick sparrow
#

second last, sure

#

the inside of the inverse cos operator should be the reciprocal of 1.8939

#

$ \frac{1}{\cos\beta} = 1.8939 \implies 1 = 1.8939\cos\beta$

#

good bot

vale dockBOT
#

@north scarab Has your question been resolved?

north scarab
#

@sick sparrow

#

We need to make

#

Beta the subject right?

sick sparrow
#

as in, solve for it? Yes

#

That's what I meant by isolating it

north scarab
#

so

#

1/cosB = 1.8939

#

B=arcos(1.8939)

sick sparrow
#

no

sick sparrow
#

so you would need to use the inverse operator of secant to solve for beta, arcsec

north scarab
sick sparrow
north scarab
#

yep let me fix that

#

so i got

#

1=1.8939(CosBeta)

lyric sundial
#

No need of parentheses

#

But yes

north scarab
lyric sundial
#

cos not Cos

lyric sundial
north scarab
lyric sundial
#

What is the inverse cos?

#

It's secant, right?

north scarab
#

inverse cos is

#

cos^-1?

#

right

lyric sundial
#

So the inverse of that is sec^(-1)

north scarab
lyric sundial
#

No no

#

Reciprocal inverse

sick sparrow
#

dw too much about that just focus on the procedure

north scarab
#

because ik that inverse is used to

#

get the value of the angle

#

but i never heard the phrase how u said it

#

oh so u mean

#

xyz

#

this is the answer but i have written 58 degrees, 8 minutes

#

should i have written 08?

#

or 8 is fine

stark wedge
#

this is quite the hairsplit

#

i don't think it's criminal to write 58°8' but it is very slightly atypical.

#

is this a current homework or did you get docked points for it

north scarab
#

just a bit behind im catching up

#

idk why and how i got a bit behind

#

do u have any advice for staying ahead of the content

#

including doing asigned homework ahead of time

sick sparrow
#

it really comes down to discipline imo

#

I took trig online through covid and I made it my routine to never miss a deadline and always study at minimum 1 or 2 nights before exams

north scarab
#

always study at minimum 1 or 2 nights before exams?

sick sparrow
#

also known as cramming

north scarab
#

isnt that bad/

#

?

sick sparrow
#

but if you're in a position where you can spread out your study time then that's better

north scarab
#

discipline works even if ur slow right?

sick sparrow
#

then make sure not to put yourself at a disadvantage by starting assignments early and studying in a timely manner

north scarab
#

like the questions are faily easy but it just takes my some time to complete them

stark wedge
#

how much work do you have left to do atm

north scarab
sick sparrow
#

that's the point of discipline

stark wedge
#

like how many assignments

sick sparrow
#

is that if you do it enough times it becomes your routine

north scarab
#

i dont have assignments i just got homework

#

and then a test next week

stark wedge
#

well how much homework

#

i wanna know the like

#

volume of work that you've got left to get through

north scarab
#

well I have to complete the practise questions first (fairly easy), then attempt the tutorail questions which picks up the difficulty but can still be easy

stark wedge
#

so one set of practice questions and one set of tutorial questions?

#

about how many in each?

north scarab
#

yea for each topic

stark wedge
#

...how many topics

#

maybe you could screenshot your online homework system or whatever if you got one?

#

anyway ok let me just go straight to my suggestion

#

since you say you have no schedule i will assume you have no time-dependent classes or other shit atm

north scarab
#

yea im a bit flexible atmp

#

atm

stark wedge
#

so what i suggest you do is this:

on your phone's calendar app, make an event titled "Math Homework Grind" or anything else you wanna call it
for one hour, each day Mon-Fri

#

whichever time you think is best

#

maybe 13:00 if you can't decide

#

and then, when the time comes, your phone will flash the reminder

#

and this is your signal to sit your ass down for an hour and do math stuff

#

if you think you can't manage an hour, start with a shorter time, like 30 minutes

north scarab
#

the thing is i allready do study every day especially for maths

stark wedge
#

you study math but you can't fit in time to dedicate to homework backlogs?

north scarab
#

for hours

stark wedge
#

or like idk, you could have your first such scheduled session be a test-run to see how much you can handle
point is if you dont have a schedule but have shit that needs doing, you make yourself a schedule

stark wedge
#

and during math homework grind you put away all your other study materials, and focus solely on the backlog of work you're going through.

#

if you think you can't handle an hour you can start with 30 minutes. idk if i can recommend going any further down in duration given i don't know how big/hard/laborious the questions are.

#

but my point remains the same:

#

dedicate some time to the shit that you want done.

#

and do it externally such as through your calendar app.

north scarab
#

like rn it took me like 50 mins to solve all this

stark wedge
#

ok, so one page takes you 50 minutes.

#

so dedicate 1h each day to do one page of questions.

#

do i need to remind you of the heart of my suggestion? or did you hear and understand it

north scarab
#

but note that this is prac questions, the tutorail questions takes me like a whole day

#

to complete them

stark wedge
#

one tutorial question takes you an entire day?

north scarab
#

no the whole tutorial questions for a topic

stark wedge
#

so you're saying the entire tutorial takes you a full day to complete.

north scarab
#

but it depends ofcourse, some tutorials are easier than others and range between 2-3 sometimes 4 pages

north scarab
stark wedge
#

ok

#

in that case:

#

dont set any goals for volume of completion

#

just sit your ass down for an hour and do as much as you have time for.

#

then, once the hour is up, bookmark the question you finished at.

#

and then don't touch it until the next session.

#

where you will do the exact same thing again.

north scarab
#

ive been doing that, i use the pomodoro sessions (30/5 or 50/10)

#

well not entire day exactly maybe

#

7-12h

stark wedge
#

keep doing it then ig

#

interleave with your other studies

#

though i do recommend you take multi-hour breaks so as not to burn yourself out

#

and reserve at least one day a week for no studying at all

#

unless you have abusive/toxic parents who will abuse you for doing that ig

north scarab
vale dockBOT
#

@north scarab Has your question been resolved?

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sage kestrel
#

limit x tends to 0, find (cosx-1)/x

vale dockBOT
timber swan
#

Hmm

#

Just apply L hospital

proven wasp
#

Yes.

young lion
#

🏥

sage kestrel
#

if i first put value of x in cosx, then we'll get (1-1)/x

timber swan
#

0/0

proven wasp
timber swan
#

Which is an indeterminant form

#

Which u can solve by lopital

sage kestrel
#

in theory, we should put the limit in both the numerator and denominator, right?

young lion
#

yes

timber swan
#

Yea?

proven wasp
#

In theory?

#

Wdym

sage kestrel
#

then it becomes (1-1)/lim x

timber swan
timber swan
#

🙏

sage kestrel
#

i know l' hospital rule

#

but i am trying to do it manually

timber swan
#

U know l hospital but are struggling with putting in the limit catthumbsup

glass kelp
#

isnt (1-cosx)/x a known limit

young lion
#

squeeze theorem?

glass kelp
#

its derived from sinx/x

proven wasp
sage kestrel
#

the eqn becomes 0/(lim x tends to zero, x)

timber swan
glass kelp
#

for op or for the known lim

timber swan
#

bri

#

Bro

#

Use the taylor series

#

🗣️🗣️

timber swan
sage kestrel
#

wait

glass kelp
#

idk

#

prolly urs is (1-cosx)/x^2

timber swan
#

The known limit is

#

1-cosx/x^2

#

which equals to 1/2 when x tends to zero

glass kelp
timber swan
#

Im intrigued

sage kestrel
timber swan
sage kestrel
timber swan
glass kelp
#

conjugate with 1+cosx

timber swan
glass kelp
#

sinx/x and its lost sibling

timber swan
#

What will u get

glass kelp
#

im too lazy to latex it

sage kestrel
#

.clsoe

#

.close

vale dockBOT
#
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After 15 minutes, feel free to ping <@&286206848099549185>.
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tardy sinew
#

I dont really understand what ln is and how 1 ln 1 is equal to ln1^1

turbid summit
#

it says it there... ln is the natural logarithm

#

and $a\ln{b}=\ln{b^a}$

tardy sinew
#

yeah im not sure what a natural logarithm is tbh

rocky lotusBOT
#

parabolicinsanity

tardy sinew
#

is there a simple way to explain it?

turbid summit
#

$\ln{x}=\log_{e}{x}$

rocky lotusBOT
#

parabolicinsanity

turbid summit
#

logarithm base e

#

and logarithm is the inverse of exponentiation

#

so eh, do you get it now?

tardy sinew
#

so what do i do if theres a number before it/

turbid summit
tardy sinew
#

oh

#

mb

#

im blind

#

lol

#

thanks

#

.close

vale dockBOT
#
Channel closed

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turbid summit
#

happens more than you think

#

good luck 🫡

tardy sinew
#

tanks

#

do i have to close this again?

hot tide
#

no

vale dockBOT
#
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lone reef
#

actually genuine question for me who doesnt even like touching complex world

  • is complex world natrually smaller than Real numbers?
heady pawn
#

define smaller

lone reef
#

Just wanna know that what does complex world actually do like in real life applications tho?

#

Complex plane isnt it all imaginary just for calculation?

pure mirage
lone reef
#

like the vague mostly used for?

pure mirage
heady pawn
#

water flow, time, schrodinger

lone reef
lone reef
heady pawn
#

imaginary numbers are also handy in business

lone reef
#

something plus i?

lone reef
heady pawn
#

probability, differential eqations, browning motion in finance

gleaming kindle
#

complex can be used to solve special PDEs

pure mirage
#

They make your life easier a lot of the times. For example, when you want to solve the differential equation for electromagnetic oscillations, the basic approach is x(t) = e^(lambda * t)

lost marlin
#

I don't know of any applications of complex analysis

heady pawn
#

or to solve some matrices in complex systems

lost marlin
#

But people still do it

pure mirage
#

You will end up with complex numbers but it's many times easier than doing it without them

lost marlin
#

Because they find it intriguing

heady pawn
#

the most important part is pretty much the fact that e^ix = cos(x) + isin(x)

lone reef
#

oh ye thats the fact i know

lost marlin
#

Almost all of quantum mechanics

lone reef
#

like imaginary also explains why sin cos tan cosec sec and cot existed

#

in Complex worl

lost marlin
#

Stems from imaginary numbers

pure mirage
#

Here a slide from a presentation of mine on this

lost marlin
#

Also I haven't done complex analysis so you should ask someone who has maybe it does have applications

pure mirage
#

After this, you can transfer e^(lambda * t) into an expression with sin and cos using Euler's formula/polar coordinates

lone reef
#

Pretty good.

#

Thanks yall

#

.close

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#
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summer parrot
#

Hey sorry but i have a maths test tomorrow morning and I cant get understand this at all. AI says the the north line is closer to point A when its not? why cant i just write 055 degrees as my answer? any help appreciated

summer parrot
#

true bearings are only answered from North clockwise right? point A is 55 degrees from North

heady pawn
#

reflect the point a over the line N in ur head

#

and then measure the distance from A (reflected) to W

#

which is 035

#

oh wait

#

I don't get it

summer parrot
#

i didnt understand that

heady pawn
#

I i get it

#

ur trying to measure the angle beteen a and the origin?

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from A

summer parrot
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A from O yeah i think

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From O pretty sure

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Bro this makes no sense at all

heady pawn
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!nogpt

vale dockBOT
#

Please do not trust ChatGPT or similar AI tools for mathematical tasks, as they often generate output which "sounds correct" but has numerous factual or logical errors. Use of these AI tools to answer other people's help questions is strictly against server rules (see #rules).

heady pawn
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the ai is confused about OA

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please don't use it for mathematics

summer parrot
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What do you suggest

heady pawn
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look it up on google urself

summer parrot
#

Can you help me with this question

vale dockBOT
#

@summer parrot Has your question been resolved?

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Channel closed

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#
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latent mortar
vale dockBOT
latent mortar
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Find side AB

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Know the diagonal AC = 2*sqrt13

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So I used Pythagoras to find CD

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Then now I’m trying to find BC so I can subtract it from AD to find the triangle

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Hypotenuse

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Well not the hypotenuse

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Yet

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But to find the bottom part of the triangle

slate folio
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you don't need to

latent mortar
latent mortar
slate folio
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oh nice idea

latent mortar
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I know this so far

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Idk how to find AB now though

slate folio
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have you learnt trigonometry yet?

latent mortar
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Yes

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I tried doing Tg

slate folio
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ok

latent mortar
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But I need 2 sides at least right

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Oh I have all the angles

slate folio
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yea

latent mortar
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Idk what to do with that though

slate folio
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∆ABE clearly has a right angle at E

latent mortar
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Mhm

slate folio
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you know the length of the side opposite of the 60° angle

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you want to find the hypotenuse

latent mortar
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Yes

slate folio
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what trig function should you use?

latent mortar
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Don’t I need 2 sides though

slate folio
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no?

latent mortar
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Like u need to relate 2 sides

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Tg is opposite/adjacent

slate folio
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what about other functions

latent mortar
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I don’t have adjacent

slate folio
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what about sine?

latent mortar
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Sin is opposite/hypotenuse

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But I don’t have hypotenuse

slate folio
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the hypotenuse is what we're trying to find here

latent mortar
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I can u just label it x?

slate folio
latent mortar
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Sqrt3/2

slate folio
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(√3)/2

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alr what is the length of the opposite side?

latent mortar
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4

slate folio
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actually you might have an idea of how to get the length of the hypotenuse now

latent mortar
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I think I know now

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Lemme try

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I got it

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(8*sqrt3)/3

slate folio
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nice job

latent mortar
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Thanks man

slate folio
#

!done

vale dockBOT
#

If you are done with this channel, please mark your problem as solved by typing .close

latent mortar
#

I have another question

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Should I close and open another if I need later?

wraith heart
#

ideally just close and open new one

latent mortar
#

Ok

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.close

vale dockBOT
#
Channel closed

Closed by @latent mortar

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vale dockBOT
#
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Show your work, and if possible, explain where you are stuck.
After 15 minutes, feel free to ping <@&286206848099549185>.
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• Be polite and have a nice day!

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fervent perch
vale dockBOT
fervent perch
#

we need to find all discontinues points

frozen ledge
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have you tried picturing this

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like a graph

fervent perch
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no

frozen ledge
#

do you have any idea where this might be continuous?

fervent perch
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maybe 3

frozen ledge
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mhm

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anywhere else?

earnest ingot
fervent perch
frozen ledge
fervent perch
#

limf(x) = f(x0) as x approches x0

frozen ledge
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mhm so we assume a ≠ 3 then show that lim x -> a f(x) ≠ f(a)

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if a ≠ 3 you could simply show the limit doesn’t exist so i’m assuming you’re familiar with the epsilon delta definition of a limit yes?

fervent perch
#

yes

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.close

vale dockBOT
#
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vale dockBOT
#
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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.

haughty jackal
vale dockBOT
haughty jackal
#

My logic:
$$n(R)=8^4$$
We'll calculate the number of cases when $ad-bc$ equals zero (i.e., the number of non-invertible matrices in $R$) and then subtract it off from $n(R)$ to get the number of invertible matrices in $R$.
\newline\newline
Case 1: $ad=bc=0$
$$\text{Number of matrices }=(2!\cross 8)^2$$
\newline
Case 2: $ad=bc\neq 0$
$$\text{Number of matrices }=2(7^2)$$
Therefore,
$$\text{Number of invertible matrices }=n(R)-[(2!\cross 8)^2+2(7^2)]=3742$$
But the answer is apparently $3780$. Where am I going wrong?

rocky lotusBOT
storm perch
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Oh I've done this before

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This was a recent JEE question right?

haughty jackal
storm perch
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Lemme get my document

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Ok so I'm not even CLOSE to that shit

haughty jackal
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Ouch

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I'm probably overcounting the number of non-invertible matrices

storm perch
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Wait why ad-bc

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Wouldn't it just be when the determinant is equal to 0

haughty jackal
rocky lotusBOT
storm perch
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Lemme recalculate rq

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Ok yeah you're right

haughty jackal
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Where

graceful zinc
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in both cases

haughty jackal
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Can you elaborate

storm perch
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Could you explain how you got each number of matricies?

graceful zinc
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ok tell me how did you come up with (2! X 8)^2 numbers

haughty jackal
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Okay sure

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Case 1:

Let's fix a = 0, then d can be chosen in 8 ways. Now fix d = 0, then a can be chosen is 8 ways. Therefore, ad = 0 can be formed in 2 * 8 ways.

Similarly, bc = 0 can be formed in 2 * 8 ways.

Therefore, to form ad = 0 and bc = 0 simultaneously, it can be done in (2 * 8)² ways.

graceful zinc
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"Let's fix a = 0, then d can be chosen in 8 ways. "
one of those 8 ways also include the case where d=0
it gets re counted when you say "Therefore, ad = 0 can be formed in 2 * 8"

haughty jackal
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OKAY