#precalculus

1 messages · Page 90 of 1

smoky schooner
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UAE

random swallow
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Are you sure that's a good idea?

tame linden
random swallow
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For computer courses

tame linden
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Yes I am aware
I'm in my first year

tame linden
random swallow
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Like me

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Lol

tame linden
#

Im doing that too, im kinda weak in maths

random swallow
tame linden
#

I studied a lot but i still got a very low score in my quiz 1

random swallow
#

Issokay

tame linden
#

So I'm gonna study harder 🥲

tame linden
random swallow
#

Make sure to not overwork yourself

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You got this

tame linden
random swallow
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Bye

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It's nighttime in my timezone

tame linden
random swallow
tame linden
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Omg 😭🫂

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Unexpected

random swallow
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Hell ya

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Yayyy

tame linden
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Wanna be friends

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?

bronze geyser
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where

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olympiads?

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or meritus academy now ig

random swallow
keen bone
bronze geyser
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oh

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just self teach?

keen bone
keen bone
bronze geyser
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patrick has elite ball knowedge

keen bone
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HEYYY RICKLI UR AN INFANT

keen bone
keen bone
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ricklis here

bronze geyser
valid topaz
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wut

keen bone
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@valid topaz

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ur the smartest

valid topaz
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no

bronze geyser
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stay humble

valid topaz
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mhm

simple tundra
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any of you guys know anything about probability

smoky schooner
smoky schooner
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Like geometric for exp?

bronze geyser
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just use tree diagrams for begginers

simple tundra
grim rock
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i’ve spotted you in the wild

undone pumice
keen bone
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hiiii

keen bone
spice crown
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can you prove that at least one of $\pi\pm e$ is irrational

obsidian monolithBOT
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Tangent

hoary thorn
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Yea it is very simple

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Let a = π + e

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b = π - e

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a + b = (π + e) + (π - e) = 2π

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Now, if a and b are both rational, a + b, i.e. 2π should also be rational

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But, 2π is not rational (kI = irrational, where k = rational number (other than 0), I = irrational number)

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Hence, at least one of a and b is irrational

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But we cannot prove that both a and b are irrational

crimson lintel
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,w is pi +e irrational

obsidian monolithBOT
smoky furnace
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can anyone suggest a good youtube channel/playlist/course/series to learn calculus

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im familiar with the basics, integrating formula, differentian, UV rule U/V rule etc.

smoky furnace
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substitution method

smoky furnace
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thank you

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im having trouble with understanding/learning the use of trigonometric formulae in integration, so must i revisit basic trigonometry?

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the only problems im having is with the difficult ones

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like

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int (1/quadratic)

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those ones

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x^2 - a^2

valid topaz
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ohh

smoky furnace
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otherwise im ok with trigonometry

valid topaz
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there's a formula for that

smoky furnace
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yea

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i have written the formulae

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hold up

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the difficulty im having is with remembering these and implementing during exams

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and partial fractions method

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like it doesnt seem to occur to me

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during examinations

valid topaz
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js need to remember the basic cases

smoky furnace
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like

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when i solve questions

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i usually kind of have to look at hints

valid topaz
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well the only advice i have is to do a ton of problems - important stuff is something you start to retain at that point

smoky furnace
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oke

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is mtg ok to solve questions from?

valid topaz
smoky furnace
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i bought this book second hand as i cannot afford a new one

valid topaz
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so ye

smoky furnace
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oke mate

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thanks for the help

tacit wren
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what counts as precalclus?

raw hill
tacit wren
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Ohh

raw hill
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Note that us precalculus is a bastardised compilation of stuff under a trenchcoat, at least half of which should have been covered in prerequisite courses

tacit wren
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What if I already do calculus but im still precollege?

raw hill
raw hill
tacit wren
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cuz i pciked i was pre college

raw hill
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But I digress

tacit wren
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Yeah i get wymm

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i did calculus when i was 17 so kinda weird

undone pumice
viscid thistle
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Should I use Desmos for polar or is there another software that’s better

jaunty lake
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anyone know how to do this cool stuff

hasty mica
unreal zenith
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so answers are:
-11
6
sqrt(2)
-3

undone pumice
bronze geyser
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Yeah what the other three said, just unwind it like its a tangled noose yk

eager meteor
grim rock
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is it just to what the power e is to

pseudo crown
# grim rock is it just to what the power e is to

it is more like a property of log, suppose you had log 10^8, we will assume the base to be 10 for now, you can take the 8 in the front and then you would be left with 8*log10 which is just equal to 8 because log10 with base 10 is 1

round geyser
jaunty lake
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what about just lne?

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same as ln^e i suppose?

signal cipher
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guyss well give me tips this year calculus will start

undone pumice
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ln(e^a)=aln(e)=1a=a as another example of how this could be useful

uncut mulch
undone pumice
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also need strong algebra fundamentals for algebraic manipulation purposes

round geyser
undone pumice
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Power Property of Logarithms

round geyser
valid topaz
round geyser
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Yes

round geyser
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Is that similar

undone pumice
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yeah

round geyser
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Now we know laws of logs are inverses of laws of exponents

undone pumice
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Basically imagine you have log((a^m)^n)

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And lets say the base of that log is a

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we know the result should be m^n

round geyser
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log(ab)=log a + log b (-) a^m* a^n = a*m+n

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Like that

undone pumice
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uh

round geyser
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I was trying to relate what’s the addition rules on logs to exponents

marsh bloom
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the result shld be m*n

undone pumice
marsh bloom
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Then correct

nimble sorrel
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hello
I am working through precalculus by stewart, I was wondering if anybody has advice concerning the amount of exercises I should be doing (there are like 100 per subchapter)

gaunt surge
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You can do those questions without having to buy MTG books or any book for jee : )

gaunt surge
# somber ingot What does MTG stand for?

Modern times group it's just a company which sells book for competitive exam like jee neet bitsat in India( previously i was wrong about the fullform now i have corrected it )

somber ingot
gaunt surge
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But surely will try my best to solve it

somber ingot
undone pumice
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a lot of it is like

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algebra review

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and then theres like some trig work

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log work

gaunt surge
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Yeah

undone pumice
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umm matrices work

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learn about some stuff u need for calc like, difference quotient, concavity

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just ... what it sounds like. foundations to take calculus and stuff i guess

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im in the class rn so there might be stuff im missing in my overview cus like we haven't learned it yet butttt yeah

somber ingot
gaunt surge
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Some previews what we are going to study in calculus and it does act like basic foundation of calc( differentiation and integration)

undone pumice
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covering past classes

somber ingot
undone pumice
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its like

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uh

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it just like

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goes over some of the stuff u learned in past classes

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and builds on it

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igs

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also something else is like, at my school. you can take precalc in 10th grade if u take integrated 2 in 9th grade

somber ingot
undone pumice
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and pass with an A

undone pumice
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eg: concavity

undone pumice
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inverse of rationals

undone pumice
somber ingot
undone pumice
undone pumice
somber ingot
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Inverse of rationals?

undone pumice
undone pumice
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how to take their inverse

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like dyk the inverse of a function rn? like, inverse of x^2 would be sqrt(x). so imagine that with rationals (its just algebraic manipulation that i haven't done before this class(

undone pumice
# undone pumice

or if kids in integrated 2 dont pass with an a, they take integrated 3 then precalc in 11th. soooo some kids in my class are learing new stuff from skipping from integrated 2 that was covered in integrated 3

gaunt surge
# somber ingot WHat is concavity?

Concavity is like you get to know the curvature of the graph on the basis of Double differentiation ( what sign it's show will tell you how the graph curves is going to be )

undone pumice
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yeah, concave down means the graph is changing at a decreasing rate, and concave up means the graph is changing at a increasing rate

gaunt surge
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If (f(x)) < 0 ( negative ) it's going to downward parabola

If (f(x))>0 ( positive) it's going to be upward parabola

undone pumice
gaunt surge
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Bruhh

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Nvm

gaunt surge
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And it is from which country ? ( Meant to say who can take this course )

undone pumice
undone pumice
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im in ap precalc. , um lemme google the contents (dont go after me for ai overview)

valid topaz
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hmmm

somber ingot
gaunt surge
undone pumice
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@somber ingot bump

somber ingot
somber ingot
gaunt surge
undone pumice
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concave up means its increasing mire and more

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if increasing you can think of this like, an exponential

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if decreasing but concave up, that means its decreasing but getting less decreasing, closer to 0

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and if its decreasing concave down, it keeps deceeasing by more and more

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if its increasign concave diwn, its approaching 0, increasing by less and less

gaunt surge
somber ingot
somber ingot
undone pumice
round geyser
undone pumice
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switching concavity

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which can be represented

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with interval form

round geyser
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U know what I mean

undone pumice
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like this

undone pumice
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the like co identity whatever

round geyser
round geyser
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But in radians

undone pumice
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ik wut u mean

round geyser
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Good

undone pumice
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thnakfully my class is done with unit circle work

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we're on like

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csc, cot, sec

round geyser
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I think doing radians is way easier then degrees

round geyser
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Went*

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Btw I get 91 on the test

undone pumice
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yeah

round geyser
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My teacher even taught us the shortcut

undone pumice
round geyser
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Like 7pi/6

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pi/6 is 30

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Take 7 and multiply by 30

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For me that is easier then multiply by 180/pi

undone pumice
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yeah thats what i do

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in my head

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its kinda just what i figured out after a while

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but, i have the unit circle memorized in radians anyway, so not like it matters too much

foggy forum
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2 pi radians = 360 degrees is all you need tbh

round geyser
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Also pi radians =180 degrees

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Ryze

foggy forum
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yeah

round geyser
foggy forum
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no i dont think so

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can you explain it?

undone pumice
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if you have like, 5pi/6

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and you want the reference angle

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5pi/6 is in quadrant 2

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pi-5pi/6=pi/6

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use pi/6 and change coords signs

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to find values

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type stuff

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make sense?

foggy forum
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wdym by reference angle

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isnt 5pi/6 just 150 degrees?

undone pumice
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uh reference angle is like

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that angle in quadrant 1

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like the equivalent of it

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some people memorize quadrant 1 and just use reference angle to figure out everything sign

foggy forum
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okay

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i suppose

round geyser
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Reference angle to memorize
pi/6 radians= 30 degrees
pi/3 radians =60 degrees
pi / 4 radians= 45 degrees

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You notice 3 goes to 6 and 6 goes to 3

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And 45 take it’s 4 and place it over pi?

somber ingot
gritty shale
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frq 3

undone pumice
gritty shale
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oh i alr took ap precalc

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idk why i didn’t finish what i was gonna say

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i loved frq 3

undone pumice
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i dont mind the calc ones

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1 and 2

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but 3 and 4 lwk kindda hell for me

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got marked off like 3 points on the last test cus i erm might have misread frq3 and misjudged the period..(in my defense it was sumn in fractions) and that test lwk dropped my grade 8% (before curve)

rocky silo
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What’s frq3

undone pumice
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uh

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we're talking bout

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frq3 for ap precalc

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specific style of question (aka trig modeling)

rocky silo
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I’m in ap precal

undone pumice
rocky silo
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Idk what that is

undone pumice
rocky silo
undone pumice
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the ap exam will give you frq's (long word problems)

gritty shale
undone pumice
gritty shale
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oh for precalc

undone pumice
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xd

rocky silo
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Oh free response q3??

undone pumice
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yeah

rocky silo
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I have not been studying for so test

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Ap

undone pumice
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oh

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well u should at least study a bit in april

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cus exams in may

rocky silo
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Wait really

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It’s fine I never really study for precal either way

undone pumice
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fair

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i js usually

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study how youre supposed to

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word the responses

rocky silo
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my teacher hates me

undone pumice
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i mean my teacher makes every test close to the ap exam so we're kinda set up for success enough

undone pumice
rocky silo
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My teacher grades so hard

undone pumice
#

oop

rocky silo
#

Genuinely praying on my downfall

undone pumice
#

tests (half unit) are like 60% of our grade

rocky silo
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Same

undone pumice
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and we only have like 3 tests this semester

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so the last one (our second test of the semester) dropped my grade 8 fricking percent before a curve

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went from 106% to 98%

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and i lowkgenuinely didn't even do bad i got like a 85 or sumn

rocky silo
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He took of the entire question cus I put (2x-2)(2x+2) instead of 4(x-1)(x+1)

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Kind My fault tho

undone pumice
#

oop

rocky silo
#

106??? What is ur curves

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We don’t get any

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He thinks curves are for the weak or smth like that

undone pumice
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if like

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a lot of the class does bad

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quizzes get curved

rocky silo
#

half my class fails and he doesn’t care

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He just tells them to do better

undone pumice
#

oop

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um

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wow

rocky silo
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W teacher

undone pumice
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so far all our quizzes (out of 18) got curved down cus idk i think my class struggles with trig-

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and then this is the tests scores, the last test got curved 2 points and the first one got curved 3 points

undone pumice
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but the curve was 1pt

undone pumice
#

so they all got bumped down to out of 17

rocky silo
#

Ohhh it reduces the amounts of questions

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Tuff tuff

undone pumice
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so original score like 14/18 becomes 14/17

undone pumice
rocky silo
#

That’s nice

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My teacher is the reason I hate partial credit

undone pumice
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oof

fossil kindle
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i mean it helps the grade alot soo

viscid thistle
#

im gonna be taking ap calc next year is it hard

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in ap precal rn

uncut mulch
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depends how well ur doing atm

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if ur good with ur algebra, functions, geo/trig, exponents/logs you should be fine
If not, it's going to be a struggle

viscid thistle
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For polar coordinates if I can memorize the diff transformations am I chilling for calc bc?

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(Ik how they work)

blissful night
#

Btw @undone pumice
If you don't mind , would you be able to share your tests coz I really want to know how trig and calculus is taught, the standard, the level that it is in your country/ school

undone pumice
rigid pond
#

can somebody help me with this equation? I’m still learning calculus

y = x^2 - 4x + 3

blissful night
rigid pond
blissful night
blissful night
#

y = x² - 4x + 3 = x² - 3x - x + 3 = x(x - 3) -1(x-3) = (x - 3)(x - 1)

undone pumice
#

do you understand methods like, x factoring,, or others?

rigid pond
undone pumice
undone pumice
#

*add to -4

blissful night
undone pumice
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and if they add to a negative number and multiply to a positive number, then they must both be negative

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so what two negative numbers add to -4 and multiply to 3?

rigid pond
#

if you’re breaking it down like that

quasi meadow
blissful night
#

@rigid pond
So exactly what evelyn said, but you can actually be quick at this method if you can prime factor out the number which you get on multiplying the coefficient of x² and the constant part. Once you can factor it out, you will get the combinations which will give you the desired pair

blissful night
#

Only if y = 0

undone pumice
blissful night
#

Yeahh x= 1 or (x-1) = 0 same thing right

undone pumice
#

so plugging in you would get (x-1)(x-3)=0

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and for it to be 0, one of the parenteheses has to equal 0

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so either x-1=0, x-3=0

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now solve for x and those are the answers~

blissful night
#

It's not really calculus... More of quadratic equations

undone pumice
#

you got this glgl

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i guess more algebra right?

rigid pond
blissful night
#

No problem..... Keep learning, calculus isn't tough, trigonometry is

valid topaz
#

hmmm

rigid pond
valid topaz
undone pumice
valid topaz
#

hmmmm

blissful night
rigid pond
#

like u said

blissful night
foggy forum
#

where a=1 you just need to think of factors of c that sum to b

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x^2-4x+3, -3 x -1 = 3 and -3-1 = -4 (b)

tardy fog
#

is this like the level of differentiation / integration?

tardy fog
#

ah i didnt have access to it

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ill select undergrad

foggy forum
undone pumice
# tardy fog ill select undergrad

yeah, as u advance in hs u may wander into topics covered typically uni, i recommend going to all the channels and just cherry pickign what u need. Eg: i habe calculus and stats selected but not other uni topics

viscid thistle
#

Trig actually sucks I can’t wait for sequences

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And sums and vectors😛

undone pumice
valid topaz
#

i have scars from linear alg

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vectors shiver

simple tundra
#

you guys do vectors in precalc right?

undone pumice
#

at a kinda basic level

simple tundra
#

oh ok

undone pumice
#

its our next unit after trig suposedly

simple tundra
#

like is it ap precalc

undone pumice
#

so idk how much in depth it goes tho ik its on our syllabus

undone pumice
simple tundra
#

oh

undone pumice
#

not tested on ap exam tho

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lemme pull it up

simple tundra
#

is it matrices or unit vectors like ijk

undone pumice
#

is it like the coordinate plane mapping thing

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oh wait no nvm

simple tundra
undone pumice
#

lemme think

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heres all of unit 4

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oh yeah

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there is unit vectors

simple tundra
undone pumice
undone pumice
viscid thistle
#

trig identities is over. (for now)

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dw Its sorted layer by layer

undone pumice
#

the rest is like matrix work

undone pumice
sleek wolf
viscid thistle
undone pumice
#

looks to be about 10 thousand practice problems with diff formulas and identities...

viscid thistle
#

it's identities and e-e-e-estabilishing 🤮

undone pumice
#

guys we have to learn identities next week

sleek wolf
undone pumice
#

and my teacher isn't even gonna be here

undone pumice
sleek wolf
#

Starting trigonometry soon after finish basic algebra

simple tundra
undone pumice
#

noice

simple tundra
viscid thistle
#

time for vectors YAYAYYAYA

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I alr did polar so im skipping that

undone pumice
#

nice

sleek wolf
#

By basic algebra I mean these identities some basic inequality etc

undone pumice
#

mm nice glgl

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igs like, alg2 level or so?

sleek wolf
#

For kinematics do you need calculus??

sleek wolf
#

Kinematics 1D not 2D

viscid thistle
#

You can learn without calc pretty sure

sleek wolf
#

Oh ok

undone pumice
simple tundra
undone pumice
#

algebra should be fine... i think

sleek wolf
undone pumice
#

i mean you can use calculus but idt its needed, idk tho i haven't taken any like physics or calc yet so

viscid thistle
#

Theres two diff types of kinematics in high school, usually algebra or calc

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so you don't need to

undone pumice
sleek wolf
#

Oh

simple tundra
#

for kinematics you likely don't need it

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although its useful though

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you can use it to "cheat"

sleek wolf
#

Do we need calculus in this sh

simple tundra
#

I mean its giving equations with derivatives

undone pumice
#

its basically is calculus

sleek wolf
#

Is this calculus by any chance 😭😭 it's in the theory

undone pumice
#

yes those are integrals

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uh

sleek wolf
#

Never did calculus before

undone pumice
#

and the other page was differentiation. so....

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uh

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glgl

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i mean

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looks like

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not terrible

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like basic calc level

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prolly ab type stuff in hs

sleek wolf
#

I mean idk

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That why I am asking you guys

undone pumice
#

Ah. Well... er. It is kinda undeniably calc. Is my answer.

sleek wolf
#

I'm sending pictures of some exercises just tell me that it is hard or not and we require easy to mid level calc or not 😭

simple tundra
#

I think for physics you'll probably just learn like very basic calc

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I think basic derivatives and integrals and just knowing what they really are should be enough

undone pumice
#

yeah seems simple enough

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does say at the top, "basic formulas" so, doesn't seem like it wants to go much in depth

sleek wolf
#

I guess and I hope so

sleek wolf
#

They say it's advanced but we have lower the level

undone pumice
#

looks like..

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related ratess?

sleek wolf
#

Idk man because it is at the very last of the chapter

undone pumice
#

Yeah related rates I'm pretty sure. Not terrible I suppose

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I mean it's not the kind of related rates where you have like three formulas and gotta chain rule taking variables as a function of time so...

sleek wolf
#

And they have like multiple exercises with basic to advanced and they said this is advanced question but we have lowered the difficulty

sleek wolf
#

Oh

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Its only the second chapter of physics

undone pumice
#

oh

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icic

sleek wolf
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After units and dimensions and some basic maths

undone pumice
#

im just in 9th grade so i haven't taken physics yet but

sleek wolf
#

Oh

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9th grade which school

undone pumice
#

im in the us

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we dont take physics till 11th here

sleek wolf
#

Yea so which school

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Oh

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I'm in 11th tho

undone pumice
#

ah

sleek wolf
#

Preparing for a competitive exam

undone pumice
#

jee?

sleek wolf
#

I was confused where to start from

undone pumice
#

ah

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glgl

sleek wolf
#

😭

undone pumice
#

🙏

viscid thistle
viscid thistle
sleek wolf
viscid thistle
#

That makes sense then, if its a comp then its usually harder

sleek wolf
#

Yess it is quite hard

viscid thistle
#

You’re doing Olympiad?

sleek wolf
#

The hardest exam in the world

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Arguably

sleek wolf
undone pumice
sleek wolf
#

Yes

viscid thistle
sleek wolf
#

It's harder than gaokao

viscid thistle
#

damn, have fun😭

undone pumice
viscid thistle
sleek wolf
#

If you compare sheer difficulty

undone pumice
#

i think gaokao is more ppl

#

and jee is harder

#

is what ive heard

viscid thistle
#

Yea that makes alot more sense then

copper ledge
#

in terms of sheer difficulty, JEE is not the hardest exam in the world lol. There are a lot of olympiads much tougher than that

sleek wolf
#

Gaokao = more people = more competition

sleek wolf
#

Not the hardest exam

copper ledge
sleek wolf
#

Rmo and inmo are way harder if you compare it that way

viscid thistle
#

Idk how you guys do this😭 humbled INSTANTLY

sleek wolf
#

You have 3 hours to solve 75 questions

undone pumice
sleek wolf
#

4 marks each -1 wrong

copper ledge
sleek wolf
#

Y s

sleek wolf
#

But 17 years give these exams so you can expect it to be one of the hardest in that age group except Olympiads

undone pumice
# viscid thistle Jeez what the heck

yeahh my mom got into her second choice college that had the department she majored in because she didn't score nearly so high as she wanted. my dad came to america for college tho.

viscid thistle
#

Well I took the hardest one here … the SAT 😱😱 ikr just put me in Caltech atp

undone pumice
#

thankfully im in america xd

#

so i dont have to worry about... just test scores....

undone pumice
#

haven't taken the sat yet

tulip fern
#

i got 1430 wkek_oops

undone pumice
#

oh

#

imma take it prolly this summer

sleek wolf
#

Sat is easy tbh

tulip fern
#

i feel like i scored higher this time tho

undone pumice
#

u got this trust

tulip fern
sleek wolf
#

Yesn

tulip fern
#

lowkey don't know why i struggled the first time 💀

viscid thistle
#

But lowk after polars should I do complex plane or vectors?

undone pumice
#

maybe complex

sleek wolf
#

What they ask in sat is this : 😂
In yt they said this is a hard question

undone pumice
#

i mean there are harder questions

#

module 2 end is a bit weird at times (or... maybe its js my mental fatigue at that point... but....)

tulip fern
sleek wolf
#

Lol

quick pagoda
#

Hai

sleek wolf
#

Maths is easy but idk about other subjects

tulip fern
sleek wolf
#

They might be harder

quick pagoda
#

The answer is 11

#

😰

tulip fern
sleek wolf
#

Heard someone wrote a proof of 300+ pages proving 1+1=2

quick pagoda
tulip fern
quick pagoda
undone pumice
viscid thistle
#

Just idk

sleek wolf
tulip fern
sleek wolf
quick pagoda
#

AGAHAHAHHAHAHAH

tulip fern
obsidian monolithBOT
#

literally anything

copper ledge
#

chat is cooked

tulip fern
sleek wolf
#

We ain't adding numbers as a string

quick pagoda
viscid thistle
copper ledge
#

(trying to bring back order)

tulip fern
quick pagoda
tulip fern
undone pumice
viscid thistle
quick pagoda
quick pagoda
copper ledge
sleek wolf
tulip fern
quick pagoda
quick pagoda
viscid thistle
tulip fern
viscid thistle
#

And I thought establishing identities w sum to product was hard

quick pagoda
quick pagoda
tulip fern
#

ok so basically

undone pumice
#

running from scary set theory

quick pagoda
tulip fern
#

N is the natural numers

undone pumice
tulip fern
#

it's {0, 1, 2, 3, 4, ...}

quick pagoda
tulip fern
#

it's the smallest infinite ordinal

quick pagoda
tulip fern
#

N = omega

tulip fern
quick pagoda
tulip fern
#

you need it for it to work

quick pagoda
#

Cause

#

💀😭

tulip fern
#

because

#

when we do cardinalities

#

we need |{}| = 0

#

if 0 didn't exist, this doesn't make sense

quick pagoda
#

This is legit breaking me 💀

tulip fern
#

like the number of elements in {}

#

there isn't anything by definition

#

so there's 0 elements

quick pagoda
#

Isn't cardinalities basically the number of elements in the set

tulip fern
#

informally, set theorists count like:

"0, 1, 2, 3. There's 4 elements!"

tulip fern
#

it's a set

#

everything is a set

quick pagoda
#

Yes

quick pagoda
tulip fern
#

so then we want integers, right

#

Z = {... -2, -1, 0, 1, 2, ...}

sleek wolf
tulip fern
#

to get this there's a very easy method

sleek wolf
#

Not normally

#

We don't consider 0 to be a part of natural no normally I believe

tulip fern
#

define the equivalence relation ~ on N * N

quick pagoda
tulip fern
#

as (a,b) ~ (c,d) iff a + d = b + c

sleek wolf
#

Are you a maths major? @tulip fern

tulip fern
#

then we define Z = (N * N) / ~

viscid thistle
sleek wolf
#

I ain't believing shit

viscid thistle
sleek wolf
#

Was this sarcasm

undone pumice
tulip fern
tulip fern
sleek wolf
#

If it's true bro is 2nd Terence tao

undone pumice
#

impressive

tulip fern
viscid thistle
sleek wolf
tulip fern
#

terence tao is more orz than me

quick pagoda
quick pagoda
#

EXACTLY

copper ledge
tulip fern
sleek wolf
#

Bro is getting 7 figure job

#

In a quant profile

tulip fern
quick pagoda
# copper ledge nope

Brah I thought since it goes from -a to a i should check out the even and odd function

#

Guess dint work

undone pumice
quick pagoda
tulip fern
copper ledge
quick pagoda
sleek wolf
viscid thistle
#

When are you meant to learn set theory

tulip fern
viscid thistle
#

Like what’s the point of it

tulip fern
undone pumice
tulip fern
quick pagoda
quick pagoda
sleek wolf
#

Never heard someone do maths for fun

undone pumice
#

splitting off the 1 on the right integrand and then putting the other side of

quick pagoda
undone pumice
viscid thistle
undone pumice
#

cus my schools math is lwk easy

tulip fern
#

so for example, there's a result known as whitehead's problem*

viscid thistle
quick pagoda
#

Wait

sleek wolf
undone pumice
quick pagoda
#

Are yall from Europe or like the west

undone pumice
#

im in the US

#

so west ..?

tulip fern
quick pagoda
#

Im Asian 😰💀

quick pagoda
sleek wolf
tulip fern
#

usa

undone pumice
#

im asian too

#

but i live in the US

tulip fern
#

asian

sleek wolf
#

Go study

quick pagoda
#

2nd sem

#

Rn

viscid thistle
#

My school only offers calc BC in unison with AB, so ppl end up taking the AB exam anyway

quick pagoda
#

What

undone pumice
#

oop

#

im in 9th grade..

sleek wolf
#

Lowkey

viscid thistle
#

Although I want to learn calc 2 by November

undone pumice
#

nice

#

my school makes us take ab then bc

#

so im taking ab next year

#

sigh

tulip fern
viscid thistle
tulip fern
#

idrc about the high eduction

sleek wolf
viscid thistle
#

It’s a top stem high school

quick pagoda
tulip fern
#

i'm just a random 7th grader

sleek wolf
#

Oh ok

viscid thistle
#

In the us

tulip fern
#

doing random things

viscid thistle
quick pagoda
#

Quantum mechanics is fun actually 😎

#

🗿

viscid thistle
quick pagoda
sleek wolf
#

1

tulip fern
sleek wolf
#

He will write a proof now

undone pumice
quick pagoda
tulip fern
#

by definition, even as a cardinal

sleek wolf
#

Stop asking him

copper ledge
viscid thistle
#

Isn’t a cardinal a bird

tulip fern
sleek wolf
#

What is |A| when a is null

tulip fern
viscid thistle
undone pumice
viscid thistle
#

IK THAT ONE

sleek wolf
tulip fern
#

so 1^0 = 1

undone pumice
tulip fern
undone pumice
#

because then the sum from 1 to 4 would be 4......

sleek wolf
#

13 year olds getting sat score of 1400+

#

Gng we r cooked

undone pumice
#

and then the greater intenger function is ANOTHER DISTRA-

tulip fern
#

not that i oppose it i lowk like my free enterance into college

sleek wolf
#

Ikr sat is easy fr

#

Dk why hardvard

undone pumice
sleek wolf
#

Requires sat score

tulip fern
#

all the sat does is filter out idiots ig catshrug

copper ledge
sleek wolf
#

In our case it's jee

undone pumice
#

that whole question was um..

#

def tested my knowledge ill say

copper ledge
undone pumice
#

at the edge of what i can solve

viscid thistle
#

Oh wait is set theory discrete?

copper ledge
sleek wolf
#

Universal set theory is true?

tulip fern
#

there's some super continuous sets

#

how do you think the reals are defined?

#

they don't just pop out of nowhere

undone pumice
#

took me a bit to work thru the left hand right hand separation integral thing

tulip fern
#

i recently learned some measure theory

#

apparently the lebesgue integral is much better than the riemann integral

#

like the dominated convergence theorem

undone pumice
#

i suppose after that beast of a probelm glares at hte ln im gonna take a clash royale break 😵‍💫

golden storm
#

Hellow, what websites should i use for practice (specifically calculus) that doesnt have me swapping thru pdfs, im currently at IBAAHL level math.

golden storm
wicked hearth
#

New to this bihhhhhh

#

currently struggling with Precal

#

and im like wtffff

#

any help would be cool

valid topaz
#

hmm

quasi meadow
undone pumice
viscid thistle
#

IM SORRY HOW DID WE GO FROM THIS

#

TO THIS IN ONE PAGE???

raw hill
#

catshrug seems normal catgiggle

undone pumice
#

its not that bad

viscid thistle
#

ok but like the jump is crazy

#

oh wait this is easy

#

nvm]

#

oh wait this is REALLY EASY

#

AYAYAYAYAYAIAYAYA

undone pumice
#

lol yeah its kind of like similar to the other one

viscid thistle
#

if this book tells me that the proof is left as an exercise for me one more time I will die

undone pumice
#

damn

#

i hate those

#

like..

#

wasn't ts alr proved, js show me how to do it alr

viscid thistle
#

litteraly, doing the work for them smh🥀

undone pumice
#

frfr proofs are one of my weak points which makes "prove this already proved proof" questions even more annoying

valid topaz
#

and they show up att in the aops books

viscid thistle
#

"The proof of this theorem requires mathematical induction, which is not discussed until later on. You are asked to prove this in problem 73."

undone pumice
#

thats um...

#

"It's okay! We'll just make you suffer later. Heh!"

viscid thistle
#

complex numbers is done!😛

shut galleon
#

no more complex number

viscid thistle
#

🥀

round geyser
raw hill
obsidian monolithBOT
#

Civil Service Pigeon

viscid thistle
#

$e$

obsidian monolithBOT
#

SUBLAVA

raw hill
obsidian monolithBOT
#

Civil Service Pigeon

raw hill
#

tldr it's all different ways of writing $|z|=\sqrt{(\operatorname{Re}(z))^2+(\operatorname{Im}(z))^2}$.

obsidian monolithBOT
#

Civil Service Pigeon

tulip fern
#

complex geometry is scary

#

unless you like coord bashing

undone pumice
#

My teacher gave us this story to remember the sum and difference identities …

undone pumice
hardy venture
swift shuttle
#

Algebraically

#

And geometrically actually

#

So the way to think about it is, cos (a+b) is the same as increasing the angle a by angle b
Geometrically on a complex plane, that's the same as multiplying two complex numbers

#

So you get:

  • z1 = cos(a) + isin(a)
  • z2 = cos(b) +isin(b)

And essentially, you just multiply them as you'd do with any other expression knowing that i² = -1

#

And you really just end up with a real expression that doesn't involve i, and an imaginary expression

#

That real side, is just cos(a+b), and the imaginary expression is just sin(a+b) multiplied by i

tulip fern
#

you prove that e^(ia)e^(ib) = e^(i(a+b)) first tho, dont you?

swift shuttle
#

You don't really need to

#

Because you can use the trigonometric form

#

And that suffices since we can interpret it visually/geometrically

#

Afaik exponential forms are easier for calculations yeah, but they're not obligatory

swift shuttle
#

Or rather, why would u need to prove it on complex numbers

tulip fern
#

we "use" e^ix because it works

#

but to prove that identity

#

you need to use the cosine + sine addition formulas

#

because that's how we define it

#

e^ix = cos x + i sin x is the definition

swift shuttle
#

I'm saying that you don't need e^ix at all

#

Because cosx +isinx suffices

#

But if u want to prove it using e^ix then sure ig, it's possible, just not necessary afaik

#

I hope I'm understanding ur statement correctly

valid topaz
#

hmm

tulip fern
#

i'm just using shorthand bruv

#

wait did i read it wrong

#

oops

swift shuttle
#

._."

#

It's easier for general computation to just take advantage of exponential properties in calculation

#

So yeah, it is easy to prove. But my point was that you can utilize trig forms to conclude trig identities in an easy way

#

That doesn't require much knowledge about exponents and complex numbers