#precalculus

1 messages · Page 89 of 1

round geyser
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Bc of 45-45-90 right triangle

low slate
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there's soemthing wrong with the numbers

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unless iam mistaken.

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apologies

undone pumice
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I didn’t have time for ts I’m only in precalc so I’m no the best with my calc yet with like optimization and that type shi

valid topaz
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hmm

undone pumice
#

A question on our calculator section 🥀

low slate
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oh my

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GOD

round geyser
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500 is the 500 from the tower and 1200 is from the 45-45-90

low slate
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no there's nothing wrong with the numbers

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jake you're right

round geyser
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You add them up then it’s 1700 m

low slate
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I'm so wrong, I used the wrong trig function

round geyser
#

It’s okay

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I’m also doing trig

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With y/r, x/r, and y/x

low slate
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cos(45) would be h/hypontenuse

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wouldnt do you much

undone pumice
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Ts was the function btw 🥀

low slate
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I'm just very silly sometimes

round geyser
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I’m also a senior but in HS

low slate
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I also meant hs

undone pumice
low slate
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but where are you from? learning about trig in senior hs year is odd?

undone pumice
valid topaz
undone pumice
low slate
#

was that your function?

undone pumice
low slate
undone pumice
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I sent the pic of the problem like two minutes ago

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Here lemme send it

low slate
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of the function, not the yappage.

undone pumice
#

Ah

low slate
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it looks like a trig function... a very horrendous one.

undone pumice
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200cos(pi(t)/7)+130sin(5pi(t)/12)+390

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Is the function

low slate
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is pi(t) a function of some sort or do you mean multiplied

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and do you know derivatives? I dont see a lot of other ways

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maybe try figuring out when cos(pi(t)/7) reaches a maxima

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then add that to when sin(that) also reaches a maxima

valid topaz
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ye this is a precalc test

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derivatives aren't learned yet blobcry

low slate
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so.

low slate
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ignore what I said

drowsy herald
#

Why i am trying to have fun + learn more

low slate
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not that you wanted to help others do it "with a challenge"

drowsy herald
#

Ohhh i get you now

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No worries

low slate
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sorry I surrender.

drowsy herald
#

If anyone has great questions, please don’t hesitate to send them

drowsy herald
#

Go for it

round geyser
drowsy herald
#

Ok i’ll solve

raw hill
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,w random number from -174 to 5850

obsidian monolithBOT
raw hill
obsidian monolithBOT
#

Civil Service Pigeon

valid topaz
drowsy herald
raw hill
#

Did you confuse $2^a=3$ with $2a=3$

obsidian monolithBOT
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Civil Service Pigeon

drowsy herald
drowsy herald
raw hill
obsidian monolithBOT
#

Civil Service Pigeon

raw hill
obsidian monolithBOT
#

Civil Service Pigeon

drowsy herald
#

What does the symbol stand for?

valid topaz
#

productorial

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so like ∑, but u multiply every term

undone pumice
undone pumice
low slate
#

I'd say its an ugly optimisation problem that I wouldnt do without calculus.

charred rapids
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You used wrong some properties

raw hill
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oh wait yeah lol

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wrong process right answer

charred rapids
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Second to third step

valid topaz
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hmm solving the cubic wasn't the best choice breadpensive

round geyser
valid topaz
round geyser
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My teacher made it $F_{net}=ma$

obsidian monolithBOT
valid topaz
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hmm

river drift
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$F_{\mathrm{net}} = \sum F$ by definition

obsidian monolithBOT
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cloud ☁

round geyser
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Yet

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How about $J=F_{\mathrm{net}}t$

obsidian monolithBOT
valid topaz
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isn't that like the impulse momentum theorem?

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my physics knowledge is so crappy

drowsy herald
charred rapids
obsidian monolithBOT
charred rapids
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[
2^{a}\cdot 2^{2} = 2^{a+2}
]

obsidian monolithBOT
drowsy herald
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Ohhhh yeaahhhhh

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God

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This bot is smart btw

charred rapids
brisk raft
obsidian monolithBOT
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Altanis

brisk raft
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wait Omg

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i misread mb

valid topaz
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ye i rly need to brush up on physics

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wait nvm

brisk raft
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$$J = \int F \dd t = \int \dv{p}{t} \dd t = \int dp$$

obsidian monolithBOT
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Altanis

brisk raft
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where J = ∫ F dt is the definition of impulse, F = dp/dt is newtons second law, and the third thing is by u-sub

dusky jacinth
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wwhat is the use in real life

brisk raft
#

who said that's a right angle

low slate
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you cant solve a triangle with just an angle and a length 🙁

hasty mica
#

<@&268886789983436800>

charred rapids
#

<@&268886789983436800>

hasty mica
#

Who wants free money!!!

willow dagger
#

omg free money

hasty mica
#

Nooo my free money😢

mortal crest
shut galleon
#

i got 83 on my quiz :(

undone pumice
#

wait no 14/17

frail lion
undone pumice
frail lion
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This is such a random function

undone pumice
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it was on our test sob

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i got that one wrong...

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i guessed wrong..

frail lion
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Yes so your tests are not discussed?

rough leaf
undone pumice
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my teacher just handed them back and was like... one point curve, ya'll did worse than usual (ahem i wonder why)

rough leaf
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wait do you get desmos or no

frail lion
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Yes

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But it's no use

undone pumice
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we're only allowed a graphing calc

rough leaf
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oh

undone pumice
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during tests

rough leaf
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we only get desmos on likr

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unit tests

undone pumice
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oh

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all our tests r on paper

rough leaf
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or quarter/mid quarter ones

undone pumice
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we can use desmos on the ap exam but not during any tests in class

frail lion
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You get these allowed ?

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In exam ?

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Cool

undone pumice
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i have ti nspire cx cas ii cus my teacher reccomend that one

rough leaf
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bro what

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none of the answer choices woro

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work*

undone pumice
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no thats why i got confused too

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it has to be from t=0 to t=12

rough leaf
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i forgot thag part

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yeah it’s the maximum is

undone pumice
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ill try desmos igs

rough leaf
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695.8

valid topaz
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hmm

rough leaf
undone pumice
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thx

rough leaf
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idk if i did much bur yw😭✌️

undone pumice
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lol

frail lion
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Really wierd question, can't be solved algebraically, u need a graphing calc or a very big risk

undone pumice
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yupp

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i burned like 5mins on it

frail lion
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Like when Asinx + B cosx + C is asked for min and max , it's C+√(A^2+B^2)

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If the angles were like same it would be around 628

undone pumice
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and then i gave up and moved on since the exam was timed and i already burned too much of that time

rough leaf
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this is such a horrid question icl

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i don’t know what it’s supposed to test

frail lion
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So closest would be 695

undone pumice
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yeah it was C cus my teacher marked that it was but

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sigh

valid topaz
rough leaf
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bro i would’ve js guessed it

rough leaf
valid topaz
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hmm

undone pumice
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cus this quiz dropped my grade 😔

rough leaf
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youll do better bext time

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trust

undone pumice
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i hope so..

rough leaf
undone pumice
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as long as my teacher feels nice and doesn't throw another demonic function like that then..

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and i dont have time to studdy cus i got a ela group project to do over the weekend

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rah

undone pumice
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sigh same

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romeo and juliet and every option forthe project involved recording a video

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so in my group they made me juliet, my friend is romeo, my other friend is a therapist, and we're gonna act out couples therapy 🥀

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and we have to all ts outside of school bcs we dont get no time in class bcs we're still not done with this stupid play rah

valid topaz
#

hmm

manic crown
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could someone help? I don't really understand how to find domain in equations..

native snow
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ok so

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sec is 1/cosx?

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so cos x cannot be 0

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cos x is zero at

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pi/2 + pi*k

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,tex all x except when $ \frac {1} {2} (x - \frac{\pi}{2}) \neq \frac{\pi}{2} + \pi k$

obsidian monolithBOT
native snow
#

so

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,tex $ x - \frac{\pi}{2} \neq \pi + 2\pi k$

obsidian monolithBOT
native snow
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,tex $ x\neq \frac{3\pi}{2} + 2\pi k$

obsidian monolithBOT
native snow
#

so its c

frail lion
native snow
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oh yes mb d

random swallow
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Sorry for the dumb question

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I forgot ts lowk

frail lion
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Then defined everywhere if sin or cos

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Domain all real

random swallow
frail lion
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No bro

random swallow
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Like we did for sec and csc

random swallow
#

And for tan, cos≠0, right?

frail lion
#

What

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Yeah

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Cos not equal to zero

random swallow
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Kk

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Ty

maiden mesa
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tips on anti deraritives in itegrals

undone pumice
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tho i can't rlly help u, integrals are my weak point 🥀 glgl tho

gloomy vector
#

Can I solve for x here or is this just a function?

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This is my work.

gloomy vector
# gloomy vector Can I solve for x here or is this just a function?

Never mind in the video they just graphed both functions to approximate the solution. https://www.youtube.com/watch?v=7JkY19bYF28

Keep going! Check out the next lesson and practice what you’re learning:
https://www.khanacademy.org/math/algebra2/x2ec2f6f830c9fb89:eq/x2ec2f6f830c9fb89:sol-eq-graph/v/graphical-equations-intro

You probably already solved a system of equations by graphing the equations and looking for intersection points. This method can actually be used to ...

▶ Play video
exotic barn
south anvil
#

Does anyone have time that can help me with the Unit circlecatscream

tender questBOT
#

Asking the actual question right away is more likely to get responses.

Asking "Can I ask...?" or "Does anyone know about...?" doesn't give people enough information to decide whether they can help, and answering can feel like a promise to help with the actual question, which they might find themselves unable to.

strange spire
gloomy vector
# south anvil Does anyone have time that can help me with the Unit circle<:catscream:941918398...

Courses on Khan Academy are always 100% free. Start practicing—and saving your progress—now: https://www.khanacademy.org/math/algebra2/x2ec2f6f830c9fb89:trig/x2ec2f6f830c9fb89:unit-circle/v/unit-circle-definition-of-trig-functions-1

Extending SOH CAH TOA so that we can define trig functions for a broader class of angles

Practice this less...

▶ Play video
round geyser
#

I have a friend that needs help with the bottom page and doesn’t how to do those

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Can someone help me asap

round geyser
#

Please help me asap

undone pumice
round geyser
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Second bottom page

undone pumice
#

this one?

round geyser
#

And the first one also

undone pumice
#

wait so all the problems in the pictures?

round geyser
#

Yes

round geyser
undone pumice
#

ah ok i wasn't sure

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cus there was writing in the 1st pic

round geyser
#

Like explains the ans key

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How did my teacher approached it

undone pumice
#

so the key thing to remember with the inverse functions

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is like its the reciproal, so 1 over something. so you can flip it over if it makes it easier to solve wit hthe basic 3

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and undefined is over 0, so eg: cot(0)=und, 1/tan(theta), tan(theta) must be 0, so what could that be... (also, some of these have 2 answers)

undone pumice
#

then for the cofunctions part, just by doing the horizontal shifts thing

round geyser
#

Btw me and my friend are in the same class

undone pumice
#

ah

round geyser
#

Thanks though

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I’m having a test tmr

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On these

undone pumice
#

oh

round geyser
#

And the identities

undone pumice
#

i also have a math test tmr

round geyser
#

sin(90-theta)=cos(theta)
cos(90-theta)=sin(theta)

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Then it’s reciprocal

undone pumice
#

ah cofunction thingy

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csc sec and cot?

round geyser
#

And cot(90-theta)=tan(theta)

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It’s like if I see these

undone pumice
#

ah i see

round geyser
#

Like cot(11-9theta)=smh

undone pumice
#

lol

round geyser
#

Set them equal to 90 and solve

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Will we see theta has a whole number

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Like rational

undone pumice
#

oh i see

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hmm

round geyser
#

Like this

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Who thought of that

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Just set it equal to 90

undone pumice
round geyser
#

Yes

undone pumice
round geyser
#

Ok

slow glen
#

Can someone check where ive gone wrong?
blobcry I've tried it multiple times but I always get 2 cases

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Lemme know if this is the wrong channel for it

fiery spear
#

I think a barrier for us might be familiarity with the specific notation.

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The ⊕ is xor but what's the other one

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⊙ xnor hm

slow glen
jolly karma
#

(Last line) can I cancel both (sinxcosx) pieces on top with the bottom or-

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All of that last line is over sinxcosx

drowsy sundial
#

hiii, would anyone be a dear and help me with a simple pre calc question? It’s very easy but I don’t understand how the professors answer is correct? I’m freshman undergraduate

drowsy sundial
#

thanks!

#

this is the question

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This is the professors answer

jade basalt
drowsy sundial
#

I was stuck here for reference

drowsy sundial
#

how is it -1 and not 1?

echo sinew
#

Can g be equal to 0, if you're doing f/g ?

drowsy sundial
#

nope

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not at all

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the denominator cannot be 0

echo sinew
#

Awesome

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That's why x can't be -1, because x=-1 would make g equal to 0

jade basalt
#

in the original expression

drowsy sundial
#

OHH

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wait so

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do we just try to see what equals g to 0

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and not include it in the domain?

jade basalt
drowsy sundial
jade basalt
drowsy sundial
#

I took math in Arabic my entire life and I took it In English during my undergraduate, so I’m new to the definitions, sorry.

#

Does null mean error?

jade basalt
#

so at x=-1, the step of canceling the factors is wrong

jade basalt
jade basalt
drowsy sundial
echo sinew
#

I guess it's more a CS term

drowsy sundial
#

ohhhhh now I understand

#

thank you so much :D!

jade basalt
drowsy sundial
#

thanks so very much!

jade basalt
#

have a great day ❤️

toxic turret
#

I made this question by myself 😊

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Could any body find the answer for this

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And it doesn't give gibberish values

toxic turret
undone pumice
brisk verge
#

polar coordinates is pre calc?

echo sinew
#

I guess so

undone pumice
fleet roost
undone pumice
#

tho i alr know polar from before this class anyway

rough leaf
#

it’s not that bad

brisk verge
#

yeah i've already done it but was just wondering what it counts as

pale halo
#

When does precalc become calculus

ancient inlet
pale halo
#

Wait no I'm stupid

ancient inlet
#

...

pale halo
#

😭

ancient inlet
#

derivatives of functions

pale halo
#

But what about the calculus stuff tho bc this is in the preuni section

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Most ppl do derivatives before uni

ancient inlet
pale halo
#

What comes immediately before learning derivatives

ancient inlet
#

no idea

strong kernel
#

Is there a channel for calculus?

strong kernel
#

Thank you

raw hill
gleaming phoenix
#

Maybe even limits

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Basic ones without L hopital

pale halo
#

really?

#

damn

pale halo
gleaming phoenix
gleaming phoenix
pale halo
#

yippee

gleaming phoenix
#

What do they teach in precalc anyways?

pale halo
#

weve done some calc just not l'hopitals

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mostly integration tbh

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not much limits at all

gleaming phoenix
pale halo
gleaming phoenix
pale halo
#

yeah

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but barely any limits

gleaming phoenix
pale halo
#

the only limits i can think of is for solving problematic integrals and for differentiation from first principles

gleaming phoenix
#

Like integration lnx from 0 to 1

pale halo
gleaming phoenix
#

Then u kinda already know limits

pale halo
#

for an integral in the interval [a, b] if f(x) is undefined at x=T you just solve for [a, t] + [t, b] and set t = lim t->whatever T aproaches

pale halo
#

lmao

gleaming phoenix
#

So u havw done calc

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At a highachool level atleast

lime ore
#

i understand differentiation but i still have confusion with limit ;-;

gleaming phoenix
#

Just practice i guess

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Organic chem tutor explains it pretty well if u need

undone pumice
#

Tho ik calc from outside study yawn. Supposed to do basic calc (like difference quotient) after ap exam in may tho it’s not on our curriculum

heady bluff
#

guys i have a quick question: when factoring how do you know when to use factor by grouping vs gcf factor method? is there a particular case where one is valid and the other is not?

olive torrent
#

if the terms have something in common, then factor it out

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gcf factoring is usually valid

heady bluff
#

ohh ok

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tyy

olive torrent
#

np!

heady bluff
#

wait so it doesnt matter the amount of terms?

olive torrent
#

yes

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if there are terms that you can group

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then do it

heady bluff
#

oh ok

olive torrent
#

yea use gcf when they have a greatest common factor. use groups for when there are 4 (i think) terms that you can pair up

heady bluff
#

kk

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thx

gleaming phoenix
#

Of prerequisites

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I see

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Seems useful

teal oriole
#

Does anyone have a good way to explain logarithms? I know them well but my friend has a lot of trouble

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Like a way to represent them

clear glade
#

Structural Analysis Request: Weighted Logic System (3:3:4)
​I am seeking a peer review of the following mathematical framework. This is a system designed for Structural Optimization using a 3:3:4 weighted ratio across three variables (x, y, z):
​The Objective Function:
Let the total system be S.
S = 0.3x + 0.3y + 0.4z Variable Definitions:
​x (Reduction Variable): The process of simplifying a complex set into its base axioms.
​y (Equilibrium Variable): The identification of isomorphisms and balance between those axioms.
​z (Integrity Variable): The stress-testing phase; applying external constraints to verify the stability of the system.
​The Logic Question:
Given that z (Integrity) is weighted at 40%, while x and y are weighted at 30% each, how does this affect the Systemic Stability when external pressure is applied? Is this ratio (3:3:4) a mathematically sound distribution for maintaining a "Steel" (rigid/unbreakable) structure, or would a different ratio provide higher harmony?

undone pumice
gleaming phoenix
#

Whether its concave up or down wrt to the x axis?

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Isnt that differential calc? Or did i accidentaly miss learning something?

undone pumice
#

as in, this function is concave down on this interval

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and such

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tho it is the double derivativething since the rate at which the rate of change is at is basically second differences of a functions y values aka the second derivative

sonic hill
#

A logarithm, say like log(55) (log as in base 10) asks, 10 raised to the what power gives you 55?

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And log(55) gives you whatever that number is

undone pumice
#

my teacher had us draw stuff with arrows like this but idrk cus i alr knew logs before pc so... its kind of tricky to figure out at first

stark tree
#

Yea is just adding the base to the bottom of the right side equation

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Same goes to 2ln X=10 and you add e on the bottom of it to cancel the base itself

undone pumice
#

yeah

rugged spruce
#

What did u guys use to understand the unit circle like understanding the special terminal points and sin cos tan stuff

icy verge
undone pumice
#

Uhhh

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My teacher this year taught it like for q1 the y values is going down from 1 to 0 and the x values are going up from 0 to 1

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And it’s all over 2

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And for the numerators it’s going up or down sqrt3,2,1 (and sqrt 1 is 1 so 1/2)

undone pumice
#

That’s all the advise I can give tbh I alr knew it before precalc

gleaming phoenix
#

Gg's

swift shuttle
#

You pretty much need to know the main 4 points 0 = 2π, 90° = π/2, 180° = π, 270° = 3π/2 = -π

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You could learn some points like π/4 I guess
But the main thing is that you can memorize each angle depending on its corresponding quarter

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Assume angle x:
For the first quarter [0; π/2]: the angle x is just x
[π/2 ; π] : π - x
[π; 3π/2] : π + x
[3π/2 ; 2π] : -x

#

So any angle you get you pretty much convert into one of those and work around with it

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The purpose of having those conversions is because they're related to each other

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For example x and -x have the same cos value, x and π-x have the same sin

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Just imagine or draw the circle and your main 4 directions and think of your angle as a triangle, the x axis is your cosine value, and the y axis is your sine value

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It might be overwhelming at first, but it's really simple. Just try to work your wonders on it and understand it your way

zealous rain
#

Let Asin²x + Bsinx + C = 0 (i), and
A + 2Bcosx + 4Ccos²x = 0 (ii).

Let α = [-B + √(B² - 4AC)]/(2A), and
β = [-B - √(B² - 4AC)]/(2A).

If B² - 4AC >= 0, A ≠ 0, and x is an acute angle, then the correct option is

A. (α)² + 1/(2β)² = 1 or (β)² + 1/(2α)² = 1 always.

B. A√2 + B = 0 when x = 45°.

C. x = 45° when A√2 + B = 0.

D. None of the above.

copper ledge
#

<@&268886789983436800> ?

rugged spruce
#

He’s underrated imo probably better then the organic chemistry tutor

#

Can you guys explain these problems to me tho

undone pumice
#

and a whole circle is 2pi radians and half of one is pi radians

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and you can use that to figure out where on the circle its talking about. negative (whatever) angle means go (whatever) clockwise from teh x-axis instead, or convert it to positive by adding 2pi

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the terminal point is just wherever that angle interesects on the unit circle

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i do see that these questions appear to have answers on them already, so im not sure if you want me to still explain that part?

rugged spruce
#

Yea explain also what do the denominators mean and why are we multiplying by 2 on some of them

undone pumice
#

which part is confusing?

rugged spruce
#

So it doesn’t matter?

undone pumice
#

that its multiplying by 2/2

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so basically

rugged spruce
undone pumice
#

when u multiply by 2/2 you're making an equivalent fraction

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its just too

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make it have

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a denominator of 6

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so that you can count it by the already marked segments of pi/6 HOWEVER this is not a required step

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you could just go.... 4pi/3 is like this many degrees and goes here... . i personally never did that step but i believe its to help make it easier at least for now

#

does that make sense, choco?

rugged spruce
#

When it comes to that step no

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Bc it’s like when do we know to multiply by 2 when we get a problem like that yk

undone pumice
#

you dont

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cus u dont need to do that step

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its optional

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and completely up to your preference

#

excuse my terrible drawing but the blue lines represent every 60 deg or pi/3, and the red lines represent every 30 deg or pi/6

rugged spruce
undone pumice
#

you would look only at the blue lines measuring every pi/3, find the one in quadrant 3 representing 4pi/3, and find where it intersects

rugged spruce
#

Hmmmm

undone pumice
#

the typical unit circle looks something like this with every commonly asked (non calculator) angles and their values

#

so like, you wouldn't just break it up until 60degrees or 30 degrees. so that conversion step on that picture you sent isn't really required

rugged spruce
#

So the professor is just confusing ppl

undone pumice
#

honestly, i have the values memorized because i knew the unit circle before precalc so im not really sure how to help

rugged spruce
#

This my first time learning it

undone pumice
rugged spruce
#

Ok

undone pumice
#

i personally instead of multiplying too get a value over 6 would simply learn how to build quadrant 1 of a unit circle and learn how to apply that to the other quadrants

#

especially since you'll never see on a test (at least, a standardized one) like, 8pi/6, you will always be given a simplified fraction so, it's best to learn how to be comfortable with them

frail elk
valid topaz
#

hmm

swift shuttle
#

Those points correspond to the values √1 / 2, √2 / 2, √3 / 2

#

Whether sine values or cosine values

#

The closest you are to the center, the smaller the number on the numerator

#

So for example, π/3 is the closest to the center on the cosine axis, hence why its cosine is 1/2

muted widget
#

Guys if I want to do lnx-1>0 is the solution just x>e or x>0 and x<1 and x>e

swift shuttle
#

I assume the first option, in which case:

  • the inequality is defined for any x ∈ ] 0 ; +inf [
  • ln x > 1 meaning x > e
  • Your solutions are the intersection of your domain and solutions, which gives x > e
#

I'm not sure how you would get x < 1

undone pumice
mild estuary
#

I need help with trig

undone pumice
viscid thistle
#

guyz could u suggest some tricks or formulas which could be used in jee maths

#

(like beta function and some what gamma)

#

and if u hav please provide a yt video for tht 🙏

molten ember
#

Someone pls help with my pre calculus

uncut mulch
uncut mulch
ivory fractal
#

does anyone know how to do these questions? i've never seen these on math oly's.

copper ledge
ivory fractal
#

no

copper ledge
coral pilot
#

does anyone know how to do this question?

ivory fractal
thorny breach
copper ledge
valid topaz
wraith condor
# ivory fractal does anyone know how to do these questions? i've never seen these on math oly's.

‘how many distinct permutations of the word BANANA exist’ is just asking you in how many unique ways can the letters in BANANA be arranged. let’s look at the letter count. it is 6. we know that there are 6 choices for the first position, 5 choices for the second, 4 for the third, 3 for the fourth, 2 for the fifth, and only 1 remaining for the sixth. if you know the fundamental counting rule, this can be rewritten as 6! ways overall, or in other words, 6 • 5 • 4 • 3 • 2 • 1 .
BUT, in BANANA, some letters repeat. these repeated letters can cause duplicate arrangements, for example: if you switch 2 A’s, the word still looks the same
there are 3 A’s, those A’s can switch places in 3! = 3 • 2 • 1 = 6 ways
there are 2 N’s, those N’s can switch places in 2! = 2 • 1 = 2 ways
divide the total overall ways (6!) by the duplicates to get 6!/(3! • 2!) = (6 • 5 • 4 • 3 • 2 • 1)/(3 • 2 • 1 • 2 • 1) = (6 • 5 • 4)/(2) = 6 • 5 • 2 =
60 permutations of BANANA

#

god i wrote a paragraph

#

but there you go, small lesson in combinatorics. look into the formal formulas for permutations and combinations

ivory fractal
#

thank you so much🤗

wraith condor
gleaming phoenix
#

u gotta also know integral calculus for this

#

tend the entire sum to infinite

#

then use this concept

gleaming phoenix
#

u gotta make it into limits as a summand remember these 4 things

#
  1. if function is increasing and limit is from (0 to n) then it is greater than overall sum
#
  1. if function is increasing but limit is from (o to n-1) then it is lower than overall sum
#
  1. if function decreasing and limit from (0 to n) then it is lower than overall sum
#
  1. if function decreasing and limit from (0 to n-1) then it is greater than overall sum
wraith condor
green crown
#

Can i write QED at the end of my induction proof if i have shown that for instance a formula is not correct?

#

I think so

#

Right?

tame shard
smoky schooner
#

Does anyone need flashcards for derivative rules

exotic barn
obsidian monolithBOT
exotic barn
fossil kindle
#

what even is precalc

#

is it just a combination of trig and more complicated algebra 2

smoky schooner
#

Its an introduction of calculus

#

It focused on finding deep answers of measuring changes and statistics its like so u need a lot of knowledge of algebra and and trig cuz they are involved in it a lot if u understand them well u can understand pre calc and if u understand it u will understand calc and so on

candid condor
#

anyone have good resources for probability?

random swallow
#

Does induction count as precalc? If not, what does it count as?

vernal cypress
#

hey guys im kinda confused, my current subject is calculus but like not advanced, i think it's calc 1 and the beginning of calc 2? are those a topic of discussion over here or am i lowkey in the wrong place

random swallow
#

Well you've chosen the role pre uni math

vernal cypress
#

thank you

random swallow
vernal cypress
#

i went in there tho

random swallow
#

Gud

vernal cypress
#

im still pre uni so its kinda confusing between countries but tyty

random swallow
heady fossil
#

Any ways to prepare for pre calc next year

solid dust
#

if i like logs am i gonna like precal and calc

vernal cypress
vernal cypress
heady fossil
random swallow
rugged spruce
#

And I don’t understand them

vernal cypress
rugged spruce
vernal cypress
#

especially since i needed it in chemistry 🥹

rugged spruce
vernal cypress
undone pumice
#

yall theoretically how bad did i have to do on the second test of the semester where tests are worth 60% of our grade for my grade to drop 8% 😭 my teacher put in scores but hid them from us, so idk what i got but ik its gotta be bad

raw hill
#

<@&268886789983436800>

grim rock
#

hey guys i’m in 8th grade and in my school program we are doing algebra one- maybeee a bit of 2. i am self studying calculus and enrolling in college classes but i have a placement test to take. it’s mostly kn pre calc stuff i assume. what should i know? i’m comfortable with logarithms, unit circle, trig identities, etc but what should i grind

valid topaz
#

hmmm

grim rock
#

hi patrick

raw hill
#

<@&268886789983436800>

undone pumice
fossil kindle
undone pumice
fossil kindle
undone pumice
#

there could b

#

be

#

exceptions

fossil kindle
#

unless they arent in the usa

undone pumice
#

my district gave me an exception

#

tho i didn't take it

fossil kindle
#

which is prolly more likely

undone pumice
#

just need some working out with college first

#

and im in the us so ykw js depends

#

on the college, the high school, how advanced the student is, etc

fossil kindle
#

hmm interesting

undone pumice
#

yeah it was something the district wanted to discuss

#

idrk but its def possible for middle schoolers to take dual

#

especially in something where it's "easy" to advance if you understand

#

cant speak about the op's situation but

smoky schooner
#

Wdym dual

#

Like i can go take a calculus 2 class

#

Rn

zinc juniper
#

Do we have to be good at skibidi?

#

Because skibidi is the toilet right???

smoky schooner
#

No.l

echo sinew
zinc juniper
grim rock
grim rock
winter comet
winter comet
valid topaz
#

i wish i could enroll for college classes

winter comet
valid topaz
fossil kindle
#

does precalc even directly relate to calc

#

i swear the only relation is both have the word calculus in it

#

although precalc helps prepare for calc

grim rock
#

idek it’s a requirement so i’m grinding khan to make sure im locked

#

i should be okay

#

but i gotta take multiple placement tests so

fossil kindle
#

oh

#

is it like a dual enrollment thiny

#

thing

grim rock
#

yea i obviously still have my normal middle school program but i take the calc course sepetrakty

undone pumice
#

we had counselor visits today, my counselor wasn't a bish like in 8th grade visit time yey

swift shuttle
#

Does anyone remember the geometric proof for dy/dx for y = 1/x

undone pumice
#

did it involve a rectangle

swift shuttle
#

As per usual

undone pumice
#

hmm

#

saw it in a 3blue1brown video i think

#

uhh

#

i think its like

#

if the rectangle area always has to be 1

#

one side is x and one side is 1/x

valid topaz
#

ye

undone pumice
#

then like the increase in x by a little bit increases the vertical sliver and then you lose like some of the top to balance it out and still make its area 1

#

then like you get, y(dx)=x(-dy)

#

rearranging you get (dy/dx)=-y/x

swift shuttle
willow wraith
#

whats the proof needed?

undone pumice
#

i mean ofcs its js power rule

#

but igs

#

if u wanna prove

#

it works

#

uh

swift shuttle
undone pumice
undone pumice
#

i think

#

im pretty sure i did it right

#

hopefully...?

#

icl ive been lazy and not hopping on the calc grind recently

swift shuttle
#

Oh you're totally correct

undone pumice
#

yay

swift shuttle
#

Well, I guess I've yet to fully grasp this concept. Thanks for the further clarification

undone pumice
#

why not just power rule it instead of geometric proof?

willow wraith
#

Honestly for 1/x

#

I think it’s stupid and an idiot

#

So me personally

#

I would just say f(x) = 1/x

swift shuttle
willow wraith
#

and

swift shuttle
#

It's just a further enhancement

undone pumice
#

igs

#

good for u igs

#

im kinda lazy so idrk many geometric proofs

willow wraith
#

(f(x+0.001)-f(x))/0.001

#

😃

#

There

undone pumice
#

xd fair fair

#

like diff quotient type stuff?

swift shuttle
willow wraith
#

as change in x approaches 0

swift shuttle
#

To be precise:

[f(x+h) - f(x)]/h as h approaches 0

undone pumice
#

yeah its just like, similar to a limit, as it approaches , this is basically limit definition/difference quotient

willow wraith
#

it is th limit definition

#

I’m too lazy to write more zeros

swift shuttle
#

That's the thing, don't plug values

willow wraith
#

I will plug in values

swift shuttle
#

You're not exactly wrong, just not precise

willow wraith
#

if I can plug in values because

undone pumice
willow wraith
#

the limit of gravity as your distance becomes infinity from an object is 0

#

and I can plug distances in for that so

#

I can plug in anything I want

#

the universe doesn’t give a damn usually

swift shuttle
#

So deriving something like x² had to be done thru that

undone pumice
#

oh

#

im not in calc yet so

#

yeah we can't either

#

we had to like plug in the function, cancel out the non h values

willow wraith
#

-0.2499999875 is approximately equal of -0.25

undone pumice
#

and meanwhile the kid next to me copied off me because

willow wraith
#

good enough

valid topaz
swift shuttle
undone pumice
swift shuttle
willow wraith
#

It’s precision is good enough

valid topaz
#

must've been painful

swift shuttle
undone pumice
valid topaz
#

i forgo the limit sometimes

swift shuttle
valid topaz
#

js keep the number in my head breadpensive

undone pumice
#

lol fr

willow wraith
#

instead of h I use Δx because we all know that’s better

undone pumice
willow wraith
#

no

valid topaz
swift shuttle
valid topaz
#

and fancy is most important

willow wraith
#

if you’re about to say

#

It can be confused with dx

undone pumice
willow wraith
#

anyone who understands differentiation

#

will not confuse it with dx

#

🙏

mighty bear
#

hey guys

undone pumice
#

fr lol

mighty bear
#

im doing calc

#

like

#

i did it

swift shuttle
mighty bear
#

im going to calc 2

#

suck it losers

#

muahaha

willow wraith
#

It’s the change in x what’s wrong with that

mighty bear
#

just kidding

willow wraith
valid topaz
#

calc ii is most difficult imo

#

there's no direction tbh

willow wraith
#

it’s much more well defined than h

swift shuttle
#

That's kinda like saying f(y) = y² or having your base vectors as ô ê

willow wraith
#

that’s nothing like that at all

swift shuttle
#

You're kinda just saying screw the norm

willow wraith
#

the norm in institutions here is Δx

#

because h can be used to represent so many other things on a graph

swift shuttle
#

Cuz Δx is more common for considerable differences, hence why dx exists

willow wraith
#

while Δx on a graph is just

undone pumice
valid topaz
bronze geyser
#

what is gng on abt

undone pumice
#

we js use x and y and m and b... but no h

bronze geyser
#

hi patrick

willow wraith
#

ANY variable

bronze geyser
#

i finished the 2023 fryer

#

i suggest you check out question four

#

ill send it

swift shuttle
willow wraith
#

My school uses it for

valid topaz
#

alr

bronze geyser
#

its very fun

valid topaz
#

i'll check it out

willow wraith
#

Conics for some reason

#

And then

bronze geyser
#

here ya go

#

question three is difficult for me for some reason

willow wraith
#

It’s very often used in this area with k to represent a vertex of a parabola

#

like

#

x is just x

willow wraith
#

even if it represents something on the graph like position

#

it’s just x

undone pumice
#

haven't done vertex form in forever lwk forgot abt that

bronze geyser
#

vertex form is interesting

#

we can derive quadratic formula from it

undone pumice
#

i swear i haven't seen vertex form like at all this year

willow wraith
#

so Δx -> 0 is very easy to understand and much better 😃

undone pumice
bronze geyser
undone pumice
#

ah

bronze geyser
#

Looking at pythagorean theorum poofs is interesting too

undone pumice
#

i remember i had to sit thru like a long ahh video in 8th grade where they derived the quadratic formula

bronze geyser
#

even though i dont understand 99 percent of them

swift shuttle
bronze geyser
#

your very advanced if thats grade eight

swift shuttle
#

Doesn't that look weird to yoy

bronze geyser
#

im in canada and we dont do shit for math

undone pumice
bronze geyser
#

Jeez

#

math whiz over here

undone pumice
#

past the boring "advanced" 9th grade class they wanted us to take in 8th

#

so i could take precal now

#

anyway off for dinner now

swift shuttle
#

Nerd

bronze geyser
#

cya enjoy

swift shuttle
willow wraith
bronze geyser
#

ahem.

swift shuttle
#

Had to let it out, I get it

willow wraith
bronze geyser
#

respect to you hb

#

homeless boy

willow wraith
#

it’s your inputted x value plus an small change in x

#

there is no h axis

swift shuttle
#

I know what Δx is

swift shuttle
willow wraith
#

It’s less intuitive

swift shuttle
#

h is just a variable, it has nothing to do with literally anything

willow wraith
#

You’re observing an incredibly small change on the x axis

swift shuttle
#

The only information you need to know about h is that it's a number that's finitely small

#

Which is given when you say h ->0

willow wraith
#

Yes but if you’re teaching this definition to someone you don’t want h to be confused with a vertical change

#

After all h is usually a vertical change in other fields

swift shuttle
#

How about we use f(x) - f(x0) / x-x0

#

As x approaches x0

willow wraith
#

that’s still Δx

#

🥀

swift shuttle
#

So is h

willow wraith
#

yes but you don’t need to do all of the work to have h be in place for Δx

swift shuttle
#

How about, h is easier to write

#

:))

willow wraith
#

that’s just dependent on how you write

swift shuttle
#

Nah

#

It's objectively easier

willow wraith
#

🙅‍♀️

swift shuttle
#

Ok that's getting stupid

willow wraith
#

μ

waxen yew
#

is calc considered a pre-university course? I dont see the channel

undone pumice
#

there is a calculus channel in "early university"

waxen yew
#

Ohh ok ty

tight coral
#

why is it called pre calculus? like what do you need to know before calculus

undone pumice
#

idk it covers like

undone pumice
#

trig

waxen yew
#

limits and derv

undone pumice
#

and uh

tight coral
#

oh yea

waxen yew
#

those are kinda imp

undone pumice
#

like logs and stuff

waxen yew
#

yeaa those

undone pumice
#

i didn't know what concavity was before this class

waxen yew
#

we got rational functions too

#

functions are imp

undone pumice
#

which would have been possibly problematic in calc when like second derivative type thing

undone pumice
#

concavity is like

#

up and down

waxen yew
#

transformations?

undone pumice
#

and its based on how the rate of change of a function is

#

changing

#

no

#

like

#

is the rate of change increasing or decreasing in an interval

waxen yew
#

ohh ok

#

kinda like the slope i think

tight coral
#

why is there no statistics maths channel I really need help on that side esspecially probability.

undone pumice
#

where the change in the rate of change is equal to 0 that's where the concavity switches and this is called a point of inflection

undone pumice
#

theres a probability-statistics channel

#

is that what you're looking for?

tight coral
#

oh yeah I didnt see it thanks

undone pumice
# waxen yew thanks

yeah idk i mean its kinda not that needed but like theres some topics like second derivative dealing w/ it in calc

#

not rlly sure what else because im not in calc yet so not sure what else from precal carries over

waxen yew
#

maybe in calc

undone pumice
#

yeah igs

#

idk

#

we covered it like the first day i was in precal when i transferred so i js know it

waxen yew
#

idk if next year i should go for calc ab or just regular calc in my school

#

they seem the same

undone pumice
#

idk

#

we had counselor visits for freshmen today in our ela classes and my conuselor put me in calc ab so

#

igs im in ap calc

waxen yew
#

oh so ur not in pre calc rn

undone pumice
#

i am

#

we were doing counselor visits

#

to plan our classes

#

for next year

#

so next year im in ap calc

undone pumice
#

yah

waxen yew
#

your smart

undone pumice
#

meh theres like a few other freshies in ap pc i know

#

like... three others?

waxen yew
undone pumice
#

i took integrated 2 and 3

#

so the next course was precalc after that

#

so i transferred into ap precalc two weeks into the school year

#

from regular

#

cus my counselor was a hater and didn't tell me ap precal existed-

waxen yew
#

ap pre calc is kinda like

#

mid if im being honest

#

but if u like the class take it

undone pumice
#

i js want the gpa boost

waxen yew
#

we all do

undone pumice
#

yeah

waxen yew
#

i transferred my sophmore year

undone pumice
#

oh

waxen yew
#

wasnt allowed to take any aps or honors

undone pumice
#

oop

#

wow

waxen yew
#

i took a few my junior year

#

thats going well ig

undone pumice
#

nice

reef parrot
undone pumice
# reef parrot

this is precalc... i see definite? integrals in there...

reef parrot
#

Where should i post this 😅

#

I dont see a calculus channel

reef parrot
undone pumice
undone pumice
#

look in browse channels to see all the channels... and it belongs in the calculus channel

reef parrot
#

Thanks!

smoky schooner
#

Guys whats a good math program for learning advnaced

tame linden
#

hey everyone, I'm new here and I'm started discrete mathematics by Rosen Kenneth and precalculus

fossil kindle
smoky schooner
#

No like a program not website or app

fossil kindle
#

idrk

#

tutoring (?)

undone pumice
#

<@&268886789983436800>

keen bone
bronze geyser
#

hes asking if theres any programs for that

keen bone
bronze geyser
#

thats a question for him

bronze geyser
#

extracurricular or school provided

valid topaz
#

wat

keen bone
keen bone
valid topaz
#

hmmm