#precalculus

1 messages · Page 17 of 1

scenic coral
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No

cloud flower
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So

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8

ebon barn
chrome galleon
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oooooohhh

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see

ebon barn
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Get it?

chrome galleon
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this makes so much more sense

ebon barn
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Nice

chrome galleon
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then whatever what being show

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shown ngl*

ebon barn
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Yeah

chrome galleon
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math isnt my strong suit

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lol

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and im taking intro and precalc 1 at the same time

ebon barn
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Intro to what?

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Precalc

scenic coral
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are yall actually in precalc im concerned

chrome galleon
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im going in for cyber security but specifically i want to do system engineering

ebon barn
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And you’re in college then?

chrome galleon
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so my advisor told me there is a flip class where its both

ebon barn
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Ah

chrome galleon
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yeah just started

cloud flower
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Yea but like over the summer ive forgotten everything so now im relearning the fundamentals

ebon barn
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Yeah gl with that

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Do you know the unit circle?

chrome galleon
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me or legend?

ebon barn
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You

cloud flower
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And so im doing practice work on every kind of problem i could face

ebon barn
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That’s smart

chrome galleon
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like the one with pi symbols on it right?

ebon barn
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Yep

chrome galleon
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then yes

ebon barn
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Good

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That’ll carry you

scenic coral
cloud flower
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So i just need help and allat

chrome galleon
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180 degrees ia 1 pi

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is*

scenic coral
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ok

ebon barn
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Correct

chrome galleon
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i remember the funny things

ebon barn
chrome galleon
ebon barn
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Aka radians

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Do you need calculus to graduate Apo11o

scenic coral
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how do u know the unit circle but not fraction multiplication

cloud flower
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Dont question it

cloud flower
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For me atleast

cloud flower
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Pre calc and calc or statistics is required for me

scenic coral
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Oh that's a lotta req

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I just need to pass alg 2

cloud flower
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I already passed algebra 2

cloud flower
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But i forgot it

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So now

chrome galleon
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thats a good question

cloud flower
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I need help with pre calc

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So

ebon barn
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Calc is extremely difficult if you are still shaky on your algebra basics by the end of precalc take stats

chrome galleon
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oop

ebon barn
cloud flower
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Y=sqrtX-4

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Thats literally the first exercise question

scenic coral
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can you provide more context?

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are you doing substitution?

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Your questions appear confusing

cloud flower
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Im solving for the output

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Thats the only context i was given

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Take the formula and figure out the output

scenic coral
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Do u have a specific input?

cloud flower
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Idk broski thats all i was given

scenic coral
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are you looking for range?

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That question doesn't make sense

cloud flower
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Looking for the output

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I dont know the domain

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I can probably figure it out if i did

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I was given notes but they dont really help me

ebon barn
cloud flower
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Besides showing me the types of functions like mapping equtions graphs tables and machines

ebon barn
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Considering it’s early precalc that’s usually what they focus on

cloud flower
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Yea

scenic coral
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Using the word output is confusing though

cloud flower
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Okay yea then range

ebon barn
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y>0

cloud flower
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In the grand scheme of things this means range yea

ebon barn
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Anything square root can’t be negative

scenic coral
ebon barn
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Mb

cloud flower
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So sqrt x-4 would be equal or greater than 0

ebon barn
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If x-4 is under the square root, then yes

cloud flower
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It is

ebon barn
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Use parentheses so we know the exact statement

cloud flower
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So is that my range

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Greater or equal to 0

ebon barn
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Yep

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If an entire function is under a square root the range is y>=0

cloud flower
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Thats good to know

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Theres this other wacky one that seems to be troubling me

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X=2y^2

ebon barn
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Is x the input or output?

viscid thistle
cloud flower
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Input

ebon barn
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Ok

cloud flower
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Output is 2y^2

viscid thistle
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sqrt(x-4) has a different range

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oh sorry

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I get what you mean

ebon barn
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Solve for y

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And then we get a similar case as before

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y>=0

cloud flower
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So inclusive

ebon barn
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Correct

cloud flower
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Alright

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That step by step process is wacky

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How does it work

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You turned ^2 to a sqrt?

ebon barn
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I squared both sides which cancelled the y^2 into just y

cloud flower
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Ooh

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Thats kind of confusing

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Could you do a more in depth process

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Also what if a function isnt under a sqrt

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How would the process go

ebon barn
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There’s a lot of cases. Not much of a universal process besides analytic reasoning which is a skill you’ll pick up as you go

cloud flower
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Lets go back to the original i asked

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X-2

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Or x-4 mb

chrome galleon
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how would i go about to solving this step?

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i thought i had it but i got it wrong

cloud flower
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Idk man

chrome galleon
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nvm i got it

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it was 9/9

cloud flower
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Oh w

chrome galleon
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but now im stumped

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hold up

cloud flower
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Also im starting to wonder

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Is 12-y literally >= 0 too

chrome galleon
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hmmmmmm

chrome galleon
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nvm

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im just slow sometimes

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i got it

cloud flower
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Bro im strugglin

red bolt
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with what?

red bolt
cloud flower
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Pre calc functions

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Basically im relearning the fundimentals of functions and all that

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And i dont get any of it since i forgot it

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But im starting to understand little by little

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@red bolt

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And im seeing if x=12-y is inclusive or not making it >=0

scenic coral
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Isn't that just R

cloud flower
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Real numbers is negative infinity, infinity is it not

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= is anything that is inclusive

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Either way its still a function

red bolt
red bolt
cloud flower
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Why technically

red bolt
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to sound smarter

cloud flower
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Dawg💀

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Okay but like tell me what makes an equation a function

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Nvm i remember now

red bolt
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lol

thorn creek
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equations are not functions

red bolt
candid jetty
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Hey guys I’m back

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Got a 55 on a 10 question quiz

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So thanks for helping, I would’ve gotten a zero without you

winged wave
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Hey guys I’m self studying pre cal. Does anyone know whether khan academy is good for that

uncut mantle
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Id say its pretty good

lapis bramble
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anyone know why it say's I used the wrong variable?

lapis bramble
winged wave
lapis bramble
winged wave
foggy frigate
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So i know how to find doubling time but how am i supposed to with just this graph?

thin elm
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😭

foggy frigate
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Nah bruh they done did me dirty 😣

halcyon heart
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puro mexico

boreal swan
digital marsh
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bhappy what is the name of that formula again ?

thorn creek
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!memes

tender questBOT
viscid thistle
keen arrow
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Can someone help me please

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With precalc

junior plover
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just send the question

thorn creek
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or not

slim steppe
# boreal swan

Say that your head is the origin with your hands being a parabolic curve and your hands are above an imaginary line that is laying on your head. You could use the quadratic formula there to determine how far your hands are from your head

thorn creek
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is it just me or do the guyt's arms in that image above form a parabola

foggy frigate
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Guys i dont get this, i don’t understand how im supposed to find it through the origin

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Wait was that deleted ? Bro i dont need an answer i just need some sort of clue

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Well dont tell me the answer , i just need some light help

winged wave
swift flax
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Hi! I have some questions about pre cal. Dm me!

foggy frigate
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Ahdlgodfmtmprph

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Lets goooo

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My work is never well organized 😭

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The messier the most likely im finding it

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Y= -8(1/2)^x+8 💪

lament seal
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idk how to make the denominators the same

viscid thistle
obsidian monolithBOT
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dimpledoink

grand girder
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What would u do next

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Nvm

rapid plinth
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Anyone wanna help me out w these last two boxes

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Pretty please🥺

shy sonnet
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I think the last two boxes are both 18 because you use the formula "i+n-1" where i = top number, n = bottom number when finding the number of terms in a series. (19+0-1=18).

eternal swallow
# lament seal

Convert x²-9 to (x+3) (x-3) and multiply the other fraction by (x-3). Then add the numerators and simplify as much as possible

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Just realised you posted the message yesterday💀

keen arrow
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can someone help me

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with precalc

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PLEASE

willow bear
odd vortex
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does newtons method uses linear approximation?

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how it all connected

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where is everyone

foggy frigate
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I typed 24 and 25 and it still marks it wrong

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Is homework being picky or am i straight up wrong? This is supposed to be simple

frigid cape
foggy frigate
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😦

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Bruh thank you

chilly tundra
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howdy Im doing running start going into precalc

unborn thorn
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anyone tryna help me w a lowkey basic but making me feel stupid question for precalc

unborn thorn
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nobody 😦

scenic coral
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Pretty easy once you get started

unborn thorn
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i did

unborn thorn
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can u show me what u got?

scenic coral
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I just did the y intercept and the x intercept automatically occurred

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¯_(ツ)_/¯

scenic coral
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forgot 💀

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I think it was like 6x(x-2)/[(x+2)(x-2)]- 4?

unborn thorn
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oh shit

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i did 2x on top

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and got stuck

scenic coral
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ah, yea u need to account for -4

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xd

unborn thorn
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alr

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thx

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have a g1

grim maple
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can't cope up with calculus

odd vortex
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help me

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i dont understand what this means nd what to do can someone

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explain

zinc fulcrum
obsidian monolithBOT
thorny cypress
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he crossposted it here

zinc fulcrum
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oh lol

viscid thistle
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can someone pls explain how to find B

wintry cobalt
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i need some help with these. ik there’s a trick or rule that im forgetting about

viscid thistle
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Was I able to to answer this correctly?

sleek cipher
viscid thistle
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I think we're good now 👌💯

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My textbook was showing me a different way - still got same answers tho.

quartz oxide
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excuse me, what is an rF value?

patent crow
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Hi #precalculus
(I’m merely guessing that this question is appropriate for here….)

I have a question about terminology:

Given two functions which are composed into each other, we know that this operation is not generally commutative. So we may distinguish between f o g and g o f. What do we call the function on the right, and what do we call the function in the left?

For context, other non commutative operations have names for their last and right sides. Minuend vs Subtrahend and Dividend vs Divisor, etc.

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pine geyser
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Hi everyone, can someone please explain to me why these graphs intersect at three points?

remote dune
pine geyser
pine geyser
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<@&268886789983436800>

sleek cipher
sleek cipher
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If that is the case

pine geyser
cerulean gyro
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would this be a jump or a hole

scenic coral
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oop that sounds worse than I thought

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the lines are not meeting meaning it's a jump

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lines "jumping"

cerulean gyro
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o ok

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so it can be a jump if both endpoints are holes

scenic coral
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what

cerulean gyro
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like

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cause normally i only see jumpslike

scenic coral
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If the lines are not meeting it's a jump, i don't think thinking of the open/closed circles is a good idea

cerulean gyro
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o ok

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got it

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thanks

sleek cipher
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$x^3+5x^2+6x=0$

obsidian monolithBOT
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Arcturus ⬡

sleek cipher
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can someone explain how to find the solution to this using the cubic formula?

rugged crater
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does it say to use the cubic formula?

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or can you use anything

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because if you just take out x you can just factor

sleek cipher
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I know, I'm using this as an example problem

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Mostly because I tried to do it and ended up more confused

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I failed to read and it resulted in over a page of work and a lot of research

rugged crater
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oh ok

scenic coral
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The ... cubic formula?!

sleek cipher
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The depressed cubic formula

scenic coral
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oh hell nah why

sleek cipher
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I'm actually not writing it out for you

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but essentially, I can simplify this question into

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this is the cubic equation, the cubic formula rearranges the function to solve for x

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$\bigg(x+\frac{5}{3}\bigg)^3+\frac{-7}{3}\bigg(x+\frac{5}{3}\bigg)-\frac{20}{27}$

obsidian monolithBOT
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Arcturus ⬡

sleek cipher
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The depressed equation

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That is the long form, give me a moment

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$x=\sqrt[3]{\frac{-q}{2}+\sqrt{\frac{q^2}{4}+\frac{p^3}{27}}}-\sqrt[3]{\frac{-q}{2}-\sqrt{\frac{q^2}{4}+\frac{p^3}{27}}}$

obsidian monolithBOT
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Arcturus ⬡

scenic coral
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I still don't understand why

sleek cipher
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this is one of the two forms that the depressed cubic takes, where the function is t^3+pt+q

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(x+5/3)^3 is t

scenic coral
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Wait you can rewrite the generalized form into the depressed form?

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yo that's sick

sleek cipher
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all cubic's can be depressed, and it makes solving otherwise unsolvable cubic equations "easier"

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I'm not sure I want to even witness the quartic formula yet

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there is, importantly not a quintic or beyond

scenic coral
sleek cipher
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actually, there is not a finite quintic or beyond

scenic coral
#

truly a nightmare

scenic coral
sleek cipher
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I know, I meant like read it and figure out how it was derived

scenic coral
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or maybe not

sleek cipher
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that means that the formula for the quintic and beyond could be an infinitely long formula

scenic coral
sleek cipher
copper mango
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“I don’t understand what I have to do in this exercise. Can someone help me?”

patent crow
autumn wadi
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@cinder valve not quite sure what you're trying to do

cinder valve
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I'm not sure either

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I will wait for the prof to free and ask sth

autumn wadi
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f(x)=2-x-ln(x) and you've found the roots of this function. U then separated the function by it's roots and graphed 2-x=ln(x). You want to find where f(x) intersects that?

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is that what u mean?

cinder valve
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I found that, I needed to demonstrate there is a real root

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For something that I have to do later

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To aproximate the root using successive approximations, tangents and secants

autumn wadi
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<@&268886789983436800>

cinder valve
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Fun

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We are nerds that does not interest us

autumn wadi
cinder valve
#

I guess, it's not the point of the exercise

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Maybe it's still only an approximate value

pine light
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What is the definition of vectors? In my physics class, it is said to be a quantity to represent both magnitude and directions, while my math book defines vector essentially as a n-tuple and without mentioning to neither magnitude nor direction.

summer ruin
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neither are technically correctsotrue

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you would define a vector as any element of a vector space, while elements of the vector space satisfy some properties, in particular you can add vectors and multiply them by scalars

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a vector doesn't have to be an n-tuple either, continuous functions are vectors too

autumn wadi
scenic coral
summer ruin
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a vector space is a set and elements of that set satisfy what is known as axioms of vector space

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any set that satisfies these will be a vector space

scenic coral
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Oh that way of defining it is so weird i guess it's more general?

summer ruin
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well it looks weird untill you meet more exotic (and useful) examples of vector spaces

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in particular studying vector spaces whose elements are continuous functions is pretty important as far as applications in e. g. physics and differential equations go

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and it's pretty natural that you can add functions and multiply them by scalars, there's the zero function and f + (-f) = 0 (the zero function)

scenic coral
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a continuous function is a vector now ._.

summer ruin
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when your vectors are n-tuples, you can construct matrices and diagonalize them, such that the matrix has very simple diagonal form which is easy to work with in all applications

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fourier transform does similar thing, but it diagonalizes some complicated function into a sum of simple sines and cosinescatThimc

foggy frigate
#

Hey guys

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The dashed line is me halving it to focus on the interval 0<theta< pi/2

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Don’t need the answer just something to move me along **

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Cus i am stumped now since i dont know how to find max range

foggy frigate
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I attempted a few more and got the thing wrong but i got half the points

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Since my pi/4 was correct but it was the amplitude v^2/g

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That would be max range

viscid marsh
obsidian monolithBOT
junior plover
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<@&268886789983436800>

foggy frigate
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But it marked it as wrong

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Good to know i wasnt tripping thinking it was 1 too

strong epoch
#

Pls

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I need help

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My teacher had a mental breakdown trying to explain this she was just talking to herself the whole time and never ended up helping me

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How do I do 3. 4.

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These are the choices

pine light
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If only my teacher told me that the magnitude and direction definition was sugarcoating.

chilly void
#

Is there any easy way to evaluate this summation?

willow bear
#

conjugate shit and then it'll telescope

chilly void
vapid plaza
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multiply numerator and denominator by $\sqrt{i}-\sqrt{i+1}$

obsidian monolithBOT
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elon mask

willow bear
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sqrt(i+1)-sqrt(i) slightly better

vapid plaza
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just trivialities isleep

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but yeah you should get something which obviously telescopes, and the problem is pretty much done

prisma radish
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🤓

strong epoch
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Ty for nothing

chilly void
chilly void
viscid marsh
vivid iron
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doesn't n have to be greater than 30 for the central limit theorem to apply?

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It doesn't say that the parent distribution is normal either

hushed sphinx
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I'm no expert, but (i) "30" is at best a rough rule of thumb, not a hard cutoff. (ii) the point of the central limit theorem is that it applies no matter whether the individual experiments are normal distributed, so long as they're independent and identically distributed.

vivid iron
#

Ok sorry ive added it to my channel list

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And the stats was in uni section

obsidian monolithBOT
thorn kestrel
#

Hi, what is a_n as n approaches infinity?

hushed sphinx
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Here's a hadwavy way to approach that:

  • Obviously the limit will be somewhere between a1 and a2.
  • But it will also be somewhere between a2 and a3.
  • And since everything is linear it will be the same place, relatively speaking, between a1 and a2 as between a2 and a3.
  • So there must be some constant k between 0 and 1 such that the limit = a1 + k(a2-a1) = a2 + k(a3-a2).
  • Since you know a1, a2, and a3, you can solve for k.
copper mango
#

Someone can help me, please

noble vessel
viscid thistle
#

u all are rlly smart

copper mango
hushed sphinx
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suRjective.

noble vessel
autumn wadi
#

@digital mirage

digital mirage
#

ohhhhh thank u so much broo

digital mirage
hushed sphinx
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First, it appears, you have to invent an alpha out of thin air ...

digital mirage
#

hwp they get to that underoot 169/4 thinG

coarse marsh
#

did you read the link i sent you?

digital mirage
#

and how that underoot entered the game ?

hushed sphinx
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169/4 = (13/2)².

digital mirage
#

hello ?

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plzz help me out

digital mirage
wise spoke
#

So I had a question regarding performing row operations on matrices.
How to correctly identify what row should we perform on first? Or does it not matter since we're just converting it to row echelon form?
For example:

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We're supposed to convert this into the row echelon form and then use that to get a new system of equations to solve the equation for a unique solution.
I performed the row operation shown in the picture. The book on the otherhand performed different set of row operation and got a different answer, but since we're both converting the bottom triangle to 0s, shouldn't we have the same answer?

summer ruin
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if the answers look different it doesn't mean they are different, especially in linear algebra

wise spoke
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Oh

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hmm

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alright

hushed sphinx
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The reduced row echelon form ought to be unique, though -- but the calculaton here doesn't quite go all the way to RREF.

hushed sphinx
#

,rccw

obsidian monolithBOT
hushed sphinx
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Hmm, that doesn't go to RREF either -- but the solution it gets is definitely different from yours.

wise spoke
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Yeah, that's what I was concerned about.

hushed sphinx
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Have you checked whether your solution actually solves the original equations?

wise spoke
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yeah

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they do

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oh

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nvm

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i copied the question wrong

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i get the same answer too

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but the matrix looks different

hushed sphinx
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Oh, your original matrix is different from the book's. You have a different sign on the 5.

wise spoke
#

also one question @hushed sphinx

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if you're finding an inverse of a matrix using row method

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then no matter the order of operation

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you'll arive at the same answer right?

hushed sphinx
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Yes, you should. A matrix can only have one inverse.

wise spoke
#

Okay, thanks

thorn creek
digital mirage
#

here domain of x in 16 - x^2 will be -4 to + 4 but how to find sinx domain along with it ,

noble vessel
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When's sin(x) \geq 0 in the interval [-4,4] ?

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Take the intersection that's it

digital mirage
#

geq 0 means ?

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like sinx domain is all real numbers so now what to do , how to combine these both . intersection means , common things in both set , so then domain will be - 4 to + 4?

noble vessel
digital mirage
#

\ what this sign means here , i m not introduced with these short cuts

noble vessel
#

Ahh sorry just ignore that
It simply means greater than or equal to

digital mirage
#

ohk

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so u mean points where sinx is >= 0 in theinterval [-4 , 4] take those point and and then take intersection ?

noble vessel
digital mirage
#

but how to know sin value from -4 to +4 ?

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like sin deals with angle

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these are numbers

noble vessel
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Visualize the Unit circle

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or the sin graph

digital mirage
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sin graph has things in pi form (domain ) how to knwo about -4 and +4

noble vessel
digital mirage
#

oh yeeees , hmm now i got it , sorry that was dumb Q

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all these could also be domain , i guess ?

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cuz they all giving 0 to 1 value

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so now what is domain of sinx here lmaooo

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@noble vessel ,

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oh yes they cant be

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cuz we have limit of - 4 to +4

noble vessel
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2π > 4 , -2π < -4 < -π

digital mirage
#

so 0 to pi is the domain here ?

noble vessel
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so [-4,-π] ∪ [0,π]

noble vessel
digital mirage
#

but then range of sin x will not be from 0 to 1

noble vessel
digital mirage
#

ignore that 1st line x belongs to .....

noble vessel
noble vessel
digital mirage
#

ohhhh lmaoo i didnt saw that bruhhhh

noble vessel
#

ahh no that is between [-4,4]

digital mirage
#

so [-4,-π] ∪ [0,π] this is the final ans ?

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but pi < 4 so 4 is excluded here , it is bcz we took intersection so now these so [-4,-π] ∪ [0,π] are doamin of both fx +gx after intersection ?

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ok ty very much

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one more thing to ask ...

shell nova
digital mirage
#

which is not possible in underoot

digital mirage
#

no.of solution of this equation ?

scenic coral
#

Probably 1

heavy rapids
digital mirage
heavy rapids
#

honestly just use mod 2

dim dove
#

Only 1 solution

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1.5599

jaunty crow
#

Find the vertical asymptotes (if any) of the graph of the function. (Use n as an arbitrary integer if necessary. If an answer does not exist, enter DNE.)
f(x) =3/x^2

viscid marsh
broken lagoon
#

anyone able to help me with compostite functions?

jaunty crow
#

i got the ans

wise spoke
#

Can someone explain how J came to be about?
Shouldn't the leading diagonals in J be 1, 0, 1?

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how is -1, 1, & 2?

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both my S and M values are correct but can't figure out J

wise spoke
#

nvm

#

got it

digital mirage
thorn kestrel
#

Hi i've got a question, what's the symbol for like "equivalent" in math? I want to write that
f(x) = 5 - x is equivalent to a_n = 5 - n (the question is about arithmetic progression, but it's written in the form of a function)
but im not sure what symbol to use

#

and im not sure if this is the right channel so sorry about that

hushed sphinx
#

Just use words. Do you have such an intricate argument in mind that having a symbolic notation would make it clearer what your line of thought is?

viscid marsh
tardy aurora
#

can anyone help me with this, im takin a quiz rn and i forgot how to do this stuff

hushed sphinx
#

If you're taking a quiz, you're almost certainly not supposed to receive external help during it.

tardy aurora
#

Hmm what if I’m not taking a quiz

solar olive
#

we would help u

tardy aurora
#

ok i submitted it what was the answer tho

noble vessel
#

B I and III

tardy aurora
#

damn

noble vessel
#

What did you mark?

tardy aurora
#

C

#

wait

#

no D

noble vessel
#

hmm quite close

tardy aurora
#

i thought it was 2 and 3 but wasnt sure about 1 tbh so i just picked the one with 2 and 3

noble vessel
#

hmm x-intercept is when the graph crosses the x-axis
As you can see f(x) is positive in the interval (-inf,-3) and negative in the interval (-3,1) thus value of f(x) is zero at x=-3

tardy aurora
#

thank you, I'll make sure to study the stuff before my test I suppose

dapper estuary
#

I think the answer is no.1 but the video says no.2. Pls explain if you know why

summer ruin
#

it is 1

thorn kestrel
crisp bane
#

Is it possible to solve a trinomial using logarithms

#

I tried this

scenic coral
#

tf

digital mirage
#

is it possible to find its limit without using sandwhich theorem ....

fallen sequoia
#

How would one graph cos$(2\pi x) + i$sin($2\pi x)$?

obsidian monolithBOT
#

okeyokay

fallen sequoia
#

in the complex plane that is

#

we have $0 \mapsto 1$, $\frac{1}{2} \mapsto -1$, but $\frac{1}{8} \mapsto \frac{\sqrt{2}}{2} + i\frac{\sqrt{2}}{2}$, so how would you map that

obsidian monolithBOT
#

okeyokay

scenic coral
#

you need 3 dimensions ?

abstract portal
#

given $\log_9(x) = \log_{12}(y) = \log_{16}(x+y)$, how to find $\frac{x}{y}?$

obsidian monolithBOT
#

baba tū est

broken lagoon
#

my brain is shit could anyone help me learn some things about 1.compostiton of function

viscid thistle
# broken lagoon my brain is shit could anyone help me learn some things about 1.compostiton of f...
Khan Academy

Learn for free about math, art, computer programming, economics, physics, chemistry, biology, medicine, finance, history, and more. Khan Academy is a nonprofit with the mission of providing a free, world-class education for anyone, anywhere.

amber comet
#

can anyone help me differentiate the problem below?

junior plover
#

oh you want to differentiate?

amber comet
#

yeah

junior plover
#

you didnt mention that earlier

#

back to calculus you go sotrue

amber comet
#

😤

bright tusk
#

im rlly struggling w precalc im homeschooled but i do classes online i got sent to recovery like 5 times cuz idk what to do 😭

drowsy beacon
viscid thistle
#

@drowsy beacon hold on I am still looking for solution so do not worry answer when find out the answer.

#

these are very useful for me

lusty scaffold
#

Hey quick question dudes does the formula for arithmetic series sum start at n=0 or n=1

#

actually i think it n=1 cause you counting amount of terms

#

talkign to myself here basically but there's one for n=0,n=1 or any value you choose but just one i was thinking of was for n=1, bad question i guess lol

digital mirage
#

a sequence (Sn) is said to be bounded if and only if (|Sn| <= k ) where k is a positive real number . so my Q is if this is the case so this means those sequence which have their highest and lowest value between -k and k are said to be bounded . like -k<Sn<k is bounded but -k<Sn< m is not bounded .... ? and if this is the case then why defination of bounded sequence says that Sn is bounded if m< Sn< n exist .....

#

what are actually bounded sequence

scenic coral
#

Why would -k < Sn < m be unbounded

hot holly
#

The sequence starts at n=1 for arithmetic sequence, and each term is a + (n-1)d

#

Btw I was talking about iundied’s question

granite apex
# scenic coral Why would -k < Sn < m be unbounded

In mathematics, an inequality like this is typically used to describe a range of values for a variable (in this case, Sn). Whether or not it is unbounded depends on the values of k and m and the specific context in which it is used.

Bounded Range:

If there are specific values for k and m such that -k < Sn < m, and these values create a finite range for Sn, then the range is bounded. For example, if k = -5 and m = 10, then the range of Sn would be -5 < Sn < 10, which is a bounded interval between -5 and 10.

Unbounded Range:

If there are no specific values for k and m that limit the range of Sn, then the range can be unbounded. This means that Sn can take on values that are not restricted by any specific upper or lower limit. For example, if k = -∞ (negative infinity) and m = ∞ (positive infinity), then the range of Sn would be -∞ < Sn < ∞, which is an unbounded range because Sn can take on any real value.

In summary, whether -k < Sn < m is unbounded or not depends on the values chosen for k and m. If specific values are provided that bound the range of Sn, then it's bounded. If no specific values are given, and the range is not restricted, then it's unbounded.

digital mirage
#

my q is why this theorem exist if we have general understanding that Bounded Range:

If there are specific values for k and m such that -k < Sn < m, and these values create a finite range for Sn, then the range is bounded. For example, if k = -5 and m = 10, then the range of Sn would be -5 < Sn < 10, which is a bounded interval between -5 and 10.

digital mirage
# digital mirage

why we need this theorem which focusing on special case of -k to + k

static mesa
#

Who ever needs help with trigonometry ping me

onyx drum
marble scaffold
#

@cinder veldt

foggy frigate
#

Guys how can i better my algebra skills

#

Like is there a website for that? My skills are starting to become better as I learn more calculus but I want to be able to ace calc because of my first failed test. If the concepts remain as easy as they are now then its just the algebra i need

viscid marsh
#

do the same for the second

warped cipher
#

but if you're looking for a website use khan academy

golden frost
#

Can anyone remind me how I would solve this problem

summer ruin
#

trig identities

golden frost
summer ruin
#

first of all what identities can you recall

golden frost
summer ruin
#

what can you say about tangent

golden frost
#

opp/adj

summer ruin
#

in terms of sine and cosine

golden frost
#

uh, idk

summer ruin
#

$\tan (x) = \frac{\sin (x)}{\cos (x)}$

obsidian monolithBOT
#

Transparent Elemental

golden frost
#

ah ok

foggy frigate
foggy frigate
native fulcrum
#

Can someone please help me with this question

digital mirage
#

difference b/w limit point and limit of sequence

#

plzzz tell me in simplest way possible , i cant understand the difference

onyx drum
onyx drum
digital mirage
#

really ? like almost same or exactly same ?

onyx drum
digital mirage
#

i m asking about limit point vs limit of a sequence

digital mirage
onyx drum
swift oxide
#

Hello, can someone help me factorize this : mx^2 -(2m-1)x + m -1 without using delta.Thanks

viscid thistle
#

and -inf

fiery heath
#

Does anyone have any conversion sheets i can memorize?

minor pollen
willow bear
#

like unit conversions?

obsidian monolithBOT
#

Progameyen

obsidian monolithBOT
#

Progameyen

onyx roost
#

Is it ok if I ask help for assignment

viscid thistle
#

hi sorry with respect to a calc question is 1+cosx = 2cos^2x

#

if so how

hushed sphinx
#

That is true only when x is a multiple of 120°.

#

On the other hand 2cos²(x) = 1 - cos(2x) for all x; that looks somewhat like your equation :-)

digital mirage
#

how 3 point is true (2-e , 2+e ) belongs to set {1, 2, 3 }

hushed sphinx
#

The point 2+e/2 (where e is some small positive real) is an element of (2-e,2+e) but is not an element of N.

digital mirage
#

how point number 3 is correct

hushed sphinx
#

Same, though. No matter which positive number you choose for e, the set (2-e,2+e) will always contain a number (many numbers, in fact) that is no one of 1, 2, or 3.

digital mirage
#

@hushed sphinx so this set contains only 1, 2 , 3 , and there is no numbers in between ? so { } means this ? like if instead we used [ ] or ( ) that means infinite numbers are there b/w 1, 2,3 like 1.2 , 1.3 etc

#

this is what ur saying right ?

hushed sphinx
#

The notation {1,2,3} means a set whose only elements are the exact numbers 1 and 2 and 3.

digital mirage
#

ohhk thanku u so much

hushed sphinx
#

The notations (a,b) and [a,b] are quite different from that.

digital mirage
#

hmm these notions means there are infinite numbers b/w a and b

hushed sphinx
#

If a<b, there is always an infinity of numbers between a and b. The question is whether those numbers are elements of the set we're talking about. The interval notations (a,b) and [a,b] are ways too say they are, but list notation {a,b,c} doesn't say any numbers other than the ones explicitly written down are elements of the set.

delicate belfry
#

Can I simplify this more. And how if I so.

hushed sphinx
#

You could write y²(8y³-2)(5-5y³) where y = e^-200t -- but whether that constitutes a simplification is up for debate.
Or perhaps even -40y^8 + 50y^5 - 10y^2.

delicate belfry
#

Ok, I see thank you

dense mango
#

Guys I need help with deriving this function, I know the correct answer to it but I'm trying to do it myself

#

With respect to x of course, R is a constant

nova moat
#

*for sufficiently big T

severe pond
#

How can you always factorise f(x) - f(a) by x-a?

near flume
#

I've already formally proved this by setting x = log_b(c) and y = log_b(a), but is there any nice intuition for it?

frank vigil
#

@viscid thistle

viscid thistle
#

u scared me again

#

look u need this

frank vigil
#

i don’t take pre calc

warped cipher
#

you always need plug f(x) given into the function and solve

severe pond
junior plover
#

its not a simplifying technique unless you know what f(x) is

severe pond
junior plover
#

so many pings at the same time ahh

viscid thistle
#

My friend has a "degree" from harvard university and he sent me this.

#

Anyone to solve it ?

hushed sphinx
#

I don't see how any of those can be said to be "PREcalculus".

viscid thistle
#

Oh sorry my bad!

#

I need desmos on my computer rn lol

viscid thistle
#

I’m stumped ngl

onyx drum
sleek dome
#

idk why but i like integral more than diffrential

true bear
#

Is E considered a Square matrix?

#

C and G are, since they got the same number of rows and columns

thorn creek
#

a 1x1 matrix is square

true bear
#

and what is a scalar matrix?

thorn creek
#

something akin to a horse bicycle?

true bear
#

huh

thorn creek
#

that's not a term i'm used to seeing

true bear
#

aight np

thorn creek
#

it looks like some people use it to refer to a matriux that is equal to kI where k is a real number and I is the identity matrix

true bear
thorn creek
#

this is not a term normally used by actual mathematicians

#

scalars are not matrices

true bear
#

aight

thorn creek
#

i think the idae is that it's a matrix that "acts like" scalar multiplication

true bear
#

I see

thorn creek
#

since it's a scalar multiple of the identity matrix, which is both a left and right identity for the vector spaces you'll encounter at this level of your studies

true bear
#

yeah i have scalar multiplication in my chapter

#

okay then, thanks

thorn creek
#

so you'll need to learn that definition even if you'll never encounter it after the class you're currently taking lol

true bear
#

gotcha lol

hushed sphinx
# thorn creek scalars are not matrices

Well ... the ring of n×n matrices is an unital associative algebra over the scalar ring/field, and it's pretty common when talking about unital algebras to identify the underlying ring with its image in the algebra ... especially when that image is injective.

viscid thistle
#

I'm testing my understanding of multiplying complex numbers by explaining it in my own words

#

Is it correct to say that multiplying z by another complex number w results in a phase shift?

#

I'm having trouble concisely describing the result.

The multiplication creates a new complex number, m.
m = z*w
arg(m) = arg(z) + arg(w)
|m| = |z||w|

pine geyser
#

Can anybody explain to me why I got the answer wrong? The correct answer to this question is -1.2

#

I guess I have done everything right, but the answer is wrong

candid idol
#

actually idk

raven lily
#

My professor gave me this great tip about the unit circle that I've forgotten but I did write something down to remember it. Sadly, I don't think it was enough.. Does anyone have an idea of what I meant by this?

#

"For the unit cirlce, think about the xa nd y. Is it big x and small y or small x and big y"

elfin hollow
raven lily
#

honestly I can't tell

#

I think this might be something for just tan

#

Cause it doesn't make sense for sin or cos

elfin hollow
#

ohh yes that is unit circle is tan (theta) = y/x

#

this is the definition of unit circle

raven lily
#

yeah

#

idk

#

that's my only guess

elfin hollow
#

okay but this is the definition

raven lily
#

right

#

which I don't think was what he was trying to show

#

oh well

#

I'll just try to email him

snow steeple
#

why is the derivative of a vector of constant magnitude orthogonal to that vector

pine geyser
summer ruin
obsidian monolithBOT
#

Transparent Elemental

candid idol
#

and if it doesn't work then idk lol

onyx lotus
#

anyone have a video link how to solve this? i cant find something similar

summer ruin
#

you need to show two complex numbers are equal

#

when are two complex numbers are equal?

ornate depot
#

How does ^3sqrt(x) even works?

hushed sphinx
#

Are you sure you're in the right place with that?

viral mesa
north anchor
#

hey can i get tips on factoring x^8 + 8?

#

i feel like there's something i could do with roots of unity but i can't get it down

vapid plaza
#

you can find the complex roots of x^8 + 8, and pair them up to get a factorization over R

#

if that is what you want

north anchor
#

it is but i need to find the complex roots first lol

#

how would i go about that?

hushed sphinx
#

They won't be particularly nice anyway, since 8 is not a perfect eighth power. (Being a perfect third power doesn't really help us, alas).

north anchor
#

they won't be nice but how would i find them?

hushed sphinx
#

They are the eighth roots of -8, so take the eighth root of the modulus and divide its argument (± multiples of 2pi) by 8.

north anchor
#

eighth root of the modulus as in take the roots of 8 and make one negative?

#

i know this might be a stupid question. but i was never formally taught roots of unity so i'm a bit lost

#

i understand the idea behind taking the root of the modulus and the argument but idk the mechanics

hushed sphinx
#

No, just $\sqrt[8]{8}\cdot e^{k\pi i/8}$ for odd $k$.
This is not really roots of unity, just De Moivre.

obsidian monolithBOT
#

Troposphere

north anchor
#

ah okay, thanks!

#

yeah i'm even less familiar with de moivre

#

just double checking: so $(x-\sqrt[8]{8}\cdot e^{\pi i/8})$ would be a factor?

obsidian monolithBOT
#

peachscribbles

hushed sphinx
#

Yes, if you're okay with complex coefficients in your factors.

#

Otherwise you'd multiply out $(x-\sqrt[8]{8}\cdot e^{\pi i/8})(x-\sqrt[8]{8}\cdot e^{-\pi i/8})$ to get a real quadratic factor instead.

obsidian monolithBOT
#

Troposphere

north anchor
#

makes sense, thanks!

#

would that be a fourth root? or are there others

hushed sphinx
#

There are 8 different roots.

north anchor
#

based on the different values of k?

hushed sphinx
#

Yes.

pine geyser
pine geyser
orchid wasp
#

why does -ln(1/2) = ln(2)

#

im confused

summer ruin
#

1/2 = 2^{-1}

obsidian monolithBOT
boreal escarp
#

@orchid wasp

#

Here

orchid wasp
#

thank you

digital mirage
#

why they give this info taht f(x) = 0 when x= 4 . what is the need of this info here ?

#

second Q is , when they are saying f(x) = |x-4|/x-4 when xis not equal to 4 then how they are taking this |x-4|/x-4at x=4 to find the limit ?

sage lichen
#

I have ap calculus I need help can anyone help me?

warped cipher
little arch
#

Guess i screwed myself over

dim thunder
#

i need help with pre calc

wind flint
#

Dawg

#

Use the answer channels

#

They specifically designed for that 😭

dim thunder
#

how do i use it?

pine geyser
# dim thunder

Do you know what is the answer for (f-g)(x)? If you know please reply and write it here

#

So we can go on with your question

sage lichen
#

@pine geyser can u help me?

pine geyser
sage lichen
pine geyser
sage lichen
#

so to find the answer for the first one, do i just solve the equation?

#

then for the second one do i substitute 5 for t?

pine geyser
pine geyser
sage lichen
pine geyser
sage lichen
#

kk

pine geyser
# sage lichen kk

does this function even have a limit? Im not 100 percent sure what it means by the end of the population

#

it goes to infinity and it doesnt approach anything as far as i know

sage lichen
sage lichen
pine geyser
sage lichen
pine geyser
#

L'Hôpital's rule (, loh-pee-TAHL), also known as Bernoulli's rule, is a mathematical theorem that allows evaluating limits of indeterminate forms using derivatives. Application (or repeated application) of the rule often converts an indeterminate form to an expression that can be easily evaluated by substitution. The rule is named after the 17t...

#

this is somthing i havent learnt yet

digital mirage
#

why they give this info taht f(x) = 0 when x= 4 . what is the need of this info here ?

#

second Q is , when they are saying f(x) = |x-4|/x-4 when xis not equal to 4 then how they are taking this |x-4|/x-4at x=4 to find the limit ?

summer ruin
#

in the neighborhood of x = 4 f(x) is given by |x-4|/(x-4)

edgy edge
#

How would I be able to solve this?

split prairie
#

can somebody help me

jagged stump
#

guys i got a cool and fun question

#

if you knew that f(x) = 4x^n-1
n is a true positive number
and if u knew that f'''(x) = a
also "a" is a true positive number
find out how much is a-2n

#

got some tricks in it

#

its fun to solve ngl i had so much fun solving it

thorn creek
#

what's a "true positive number"

jagged stump
jagged stump
#

normal number

#

not 0.2 or smth

thorn creek
#

you mean an integer

jagged stump
#

its either 123457 to infinity

jagged stump
#

its a positive number, a one whole number

#

not 0.smth

thorn creek
#

integer

jagged stump
#

i d k

#

solve the question

thorn creek
#

yes, i am telling you, that's an integer

jagged stump
thorn creek
#

it's not that interesting, for a moment i thought it would require number theoretical techniques, but then i noticed the constraint

jagged stump
#

its fun

#

nothing too serious

thorn creek
#

also kinda above the level of this channel

#

this is precalc, people in here aren't expected to know differentiation

jagged stump
#

i did not find any other channel

thorn creek
jagged stump
jagged stump
thorn creek
#

sadly, lots of people ask questions in the wrong place

jagged stump
#

solve it dude

#

just solve it

#

i want u to have fun

#

you

thorn creek
#

i don't think iut would be fun for me

jagged stump
#

ok then how much is it

jagged stump
#

almost 18

#

u got close

#

i think you did everything correctly, review your answer and check for any mistakes in the numbers

honest meteor
#

I always enjoy it

sinful dome
#

well gettin 16 now

#

ion even know what im doing

edgy edge
#

Aight, it turned out to -8sin2x+1/x+1

jagged stump
jagged stump
sinful dome
#

well you can't really tell if the (n-1) is in the exponent or if its (4^n) - 1

#

gettin 18 the other way

jagged stump
#

the trick is simple

sinful dome
#

yeah for it to be positive integer x^(n-4) has to be 1

#

taking n to be 4 we get 16

jagged stump
#

isnt the third derivative 4(n-1)(n-2)(n-3) x^n-4

#

and thats equals to a

#

depending on that, a is multiplied by x^n-4 but where is it?

#

meaning its multiplied by 1

#

so x^n-4 should be x^0

#

n=4

jagged stump
thorn kestrel
#

hi, is it possible to turn any sequence's recurring formula into an explicit formula via some method?

obsidian monolithBOT
thorn kestrel
#

specifically this

summer ruin
#

you can just google how to solve recurrence relations

thorn kestrel
#

didnt know they were called that

jagged vine
#

can somebody please walk me through this I have a chapter test next week and don't understand how to get it from a graph

onyx lotus
#

can someone explain why this is wrong

#

i mean how did they get 7/9 instead of 17/9

hushed geode
#

Can you share how u got to the conclusion of 17

scenic coral
snow quail
#

who wants to help me with integration

#

like study with me

#

writing a really important test in 2 days

coarse jacinth
#

What topics get covered in UK A-levels?

#

I don't know where to start advanced stuff

pine geyser
unique path
#

Can anyone solve this integral?

#

Need some help ASAP

viral juniper
viral juniper
#

cause i got a really ugly answer

viral juniper
#

but it basically uses u-substitution to split the integral into two components, one with an ln integreal and one of a tan^-1 integral

#

hopefully this helps!

willow bear
#

@knotty shard do you still need help w/ this

pine geyser
unique path
#

It is ugly

unique path
viral juniper
#

Ill share soon tho

willow bear
#

ok

#

how familiar are you with limits in general

#

well ok then

#

as x goes to infinity, what happens to 9-x^2?

#

@knotty shard wait why did you just delete all your messages???

willow bear
#

you asked why $\lim_{x \to +\infty} \pm \frac{1}{9-x^2} = 0$ ...

obsidian monolithBOT
willow bear
#

why do you deny that you asked it though...?

modern valve
#

Alumi please stop trolling and denying that you asked a question

willow bear
#

you are either trolling or just very strange

#

the question is perfectly legitimate and in no way a "taint to the channel"...

#

sin(1) isn't minuscule, is it?

#

it's around 0.57 or something.

#

,calc sin(1)

obsidian monolithBOT
#

Result:

0.8414709848079
willow bear
#

oh, i must have been thinking of cos(1).

#

sin(1 radian) is about that much.

#

it is the default in calculus

#

you need to stop obsessing over which questions are "great" and which are "taints"

#

good job doing EXACTLY what i told you not to.

#

ffs

#

my reasoning for what?

#

you can view it as a criticism towards your attitude/behavior.

#

anyway if you really want an explanation of my reasoning: such dichotomies help nobody and only waste time and mental effort.

#

jesus fuck you're overthinking it

glass rampart
#

lol

glacial tiger
#

How come the limit as x approaches 0 of sinx/x = 1? I know that if I do L'hopital rule ill get 1 but is there a way to get 1 without doing that?

uncut mulch
#

sandwich

#

aka squeeze

urban vigil
glacial tiger
uncut mulch
#

sandwich/squeeze theorem

#

do a search on it then
another on
limit sin(x)/x squeeze theorem

rapid plinth
#

How tf did she work this inequality I can’t get it at all

#

Do u flip the sign when u take reciprocals?

sinful halo
#

you only flip when multipling the inequality by -1

#

she didnt flip the sign she just multiplied .007 and took out the n+1^3 nothing special

sleek oxide
#

Wait does that rule apply to divison as well? I forgot

sinful halo
#

wdym?

sleek oxide
#

The sign flip

#

Like if I divided -2 from the left side of (-2x<4)

#

I feel like I just answered my own questions..

sinful halo
#

idt so because your also doing the same to 4 and not necessarily multiplying by -1 like if it was x<4 then -x>-4 but for this example it would still be x<-2

sleek oxide
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Just checked

sinful halo
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thus removing it from the demoniator and multipling to the one on the other side

sinful halo
sleek oxide
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Is it because division is still scaling, but by a value less than |1|?

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Yup

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I wonder if we can verify this geometrically

ionic tapir
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Hi, could anyone please help with this. When will solving f(x)=x give all the intersection points between f and f^-1? I've heard that it's when f is strictly increasing but I'm not too sure. Thanks!

hallow geyser
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How would one find the equation of a parabola if the vertex (5, 0.47) and the x intercepts are 0 and 10

warped cipher
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if a graph only goes up or down solving f(x) = x shows where the line meets its flip side

warped cipher
thorn creek
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"flip side"?

warped cipher
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flip side can be also known as inverse no?

thorn creek
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f(x) = x does not necessarily have the same roots as f(x) = f^(-1)(x)

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also a function can be neither increasing nor decreasing and still have an inverse

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such functions are often pathologically weird, but they do exist

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for example the graph of inverse of f(x)=1/x intercepts the graph of f itself at every point

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since f(x) = 1/x is its own inverse

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and if you limit the domian to the positive reals, this function is monotonically decreasing over its domain

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or consider f(x) = x/2 for rational x, -x/2 for irrational x. this function is invertible but not monotonic. however, f(x) = x occurs when x=0 which sht eonly point at which the function and its inverse coincide

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hm, what about f(x) = 1+x+floor(x)? this function is increasing and is invertible (although its inverse has a weird domain)

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eh, no the inverse never coincides with the funciton

cinder ivy
frigid trout
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finding f^(-1) = (x-5)/(x-6) question

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Not sure if this work is correct

compact juniper
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ok i know this is dumb but what’s the invers of 1/2? is it 2 or -2?

compact juniper
thorn creek
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depends on which invers eyou want

mint glacier