#competition-math

1 messages Β· Page 25 of 1

topaz mist
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Oh ok XD

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But thank you anyway

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Unfortunately school is not letting me do those things splendidnt much homework

pearl holly
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Lol

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Got a 85/150 on a gauss prac. contest

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πŸ’€

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Its only grade 7

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*skill issue for my partHAHAHA

topaz mist
topaz mist
pearl holly
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These are like introductory math comp. problems

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I started grinding on the first one

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I'll grind the other one later

topaz mist
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Oooh nice

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Do you think it's doable for me ?

pearl holly
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because the entire day I have been grinding NT-Prealgebra on alcumus lol

pearl holly
topaz mist
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True

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I'll start someday hopefully

pearl holly
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You can start now

bold hemlock
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Or it's just an end of school exam

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Or something

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But ok

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You have like an 1 hour for all the questions

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So it kinda makes sence

topaz mist
topaz mist
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Like coding programming and cs stuff ???

topaz mist
solar quail
pearl holly
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Competitive Programming in terms of what people say

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:D

pearl holly
pearl holly
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because they give you data sets that you to put the inputs in

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so yeah

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Oh, and incase you didn't know, @topaz mist , they have these Problem Gens

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You can have like your own contest-style

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I find it fun to just print problems and simulate an actual math contest environment HAHA

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Oh, cool there are some other stuffs here, too

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I should make like a list of these types of resources

topaz mist
topaz mist
topaz mist
pearl holly
topaz mist
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Well if you can't submit them use it as self awareness of your current level ig

pearl holly
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Okay, wait

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@topaz mist check your dms

sleek ivy
ornate blade
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AMC is hard for the grade levels they are testing

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so students need easier questions to review the foundations and build confidence
CEMC isn't as easy as you claim if you're practicing towards AMC

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click on PCF and Euclid

bold hemlock
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I mean at least like 99% of questions I guess

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Idk how other olympiads are like

bold hemlock
bold hemlock
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AIME questions are easy, aren't they?

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Iirc

bold hemlock
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They are not

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But some old AIME questions are easy

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For sure

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No

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Accualy they are easy

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At least some of them are

sleek ivy
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No

bold hemlock
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Like "Jimmy walks a kilometers per hour he takes a break for b hours, and it takes him 420 hours to get to home, but if he was 10 km/h faster he would get to home after 2 hours"

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Seems like an easy system of equations

ornate blade
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and you haven't specified which AMC you're talking about

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you should compare with AMC 10 to be honest

swift imp
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early aime yes could be easy
late aime is not easy

ornate blade
ornate blade
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these are pretty standard for AMC 10 not 8

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but then AMC 10 is the first round of qualification

ornate blade
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so you're comparing apples to oranges

bold hemlock
warm arch
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For math and music nerds

ornate blade
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yes

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10th grade and below

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but yeah AMC is a different format, all multiple-choice

swift imp
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this is cute

ornate blade
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regardless if you just look at the material covered by each question

ornate blade
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yeah it's hard to compare

bold hemlock
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Oh

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It's I

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My bad

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lol

ornate blade
bold hemlock
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I wonder how hard is Polish MO finals in comparison with USAMO finals, probably trivial lol

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I mean of course not all questions

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Because Poland isn't bad in olympiads

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We have a lot of silver medalists on IMO

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And they often fail to do some of the questions on the last round of the olympiad(I mean at the time of the contest)

ornate blade
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well if you can only choose 6 people from each country

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the countries with the highest populations will have an advantage

bold hemlock
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Sorry I had to

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And of course I also have to post the memical photo

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That is probably like 10 years old or something Idk

bold hemlock
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6th question

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1/216 people got it

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Well accualy he didn't

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There was a mistake in his proof

bold hemlock
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Or some other story like that

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I haven't seen it

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I've just heared the story

dreamy plank
maiden panther
sleek ivy
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american olympiad team

bold hemlock
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But some IMO teams were also mostly asian

soft badger
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send questions

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hey guys does anybody has any question regarding any type of maths

bold hemlock
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You can try

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If you want to

chrome parrot
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All numbers?

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Does it mean there aren't infinitely many?

sleek ivy
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There are infinitely many primes so yea no?

chrome parrot
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So

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n = 1; 3

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So n can't be dividable by two, it's not always a prime neither a composite

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Ok 5 and 9 don't work either

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11 neither

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Ig n = 1; 3

bold hemlock
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No.

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I mean 1 is not a prime

chrome parrot
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Oh

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No

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It can't be

bold hemlock
chrome parrot
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It's 3 then

chrome parrot
bold hemlock
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It's probably 3

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But I can't solve it

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And I don't know anyone who can

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So it's probably 3

chrome parrot
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It's 3, we already solved it

bold hemlock
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But we don't know all the numbers that work

chrome parrot
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Mega Angelo13 and Sebastian GΓ³ral solved the problem

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Wait

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You are the one who created the question

bold hemlock
chrome parrot
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You just showed it to us?

bold hemlock
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It's from another server

bold hemlock
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But I'm not the author of the question

chrome parrot
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Problem solved βœ…

bold hemlock
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I mean it was created because some dude chcecked that it fails for a lot of n, to he thought "ok probably only 3 works" so he sent it to some other dude, he couldn't solve it so he sent it to another server, and we couldn't solve it, so it's unsolved lol

bold hemlock
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It's "find all p that work"

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You have no proof that there is no other p that works

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It was checked up to 3000 first prime numbers or something around that

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And so far only p=3 works

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But there is no proof

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At least for now

chrome parrot
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There is no calculator that can prove if some number p is a prime number above 13

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Not in the web

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And I am very angry if the number is like 1836829229833664829102873646472992991938473930192747920287373837

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Wolfram Alpha can't solve it either

bold hemlock
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Cool

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So it's still unsolved

high goblet
# bold hemlock

heuristically probably, cus sum 1/log(n) log(n^n + 2) converges

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um i don't see a good way to prove this

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are you sure this is solvable?

bold hemlock
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Lol

high goblet
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if this is just from exploration & ur unsure if this is open or not, it may be worth posting to #advanced-number-theory and seeing what ppl know abt it

bold hemlock
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Because people there asked me "why do I care about it?"

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And I don't have a reason

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I mean I'm just curious

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It isn't important to any mathematical reaserch I'm aware of, or something

high goblet
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basically if the question is solvable, then there'll be like factoring trick or like some modular arithmetic trick that you can do

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but there doesn't feel like much you can do, so i'd imagine the problem's open

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cus basically every problem regarding "are there infinitely many primes of the form X" is unsolved

high goblet
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why do we care about infinitely many 1 mod n primes?

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ultimately like there is no real practical application

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just say like u were curious what we currently know about primes p s.t. f(p) is prime

bold hemlock
bold hemlock
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I mean in some cases the smallest divisor is like over 100000

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But it might have some factorisation

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I mean it seems to have some factorisation

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Because it seems to be divisible by something of size near to p^2

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But it probably does not work

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I don't know any polynomial that would work for a lot of cases

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Or anything like that

high goblet
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you can probably use sieve methods to bound the number of primes with this property <= x

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actually ur bound's probably gonna be kinda awful

high goblet
bold hemlock
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I mean Ik that prime number theorem

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But where exacly

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It's like "assuming p^p+2 is a random number"

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Or something like that

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And then we sum the probabilities of a number of some number of that form being prime?

high goblet
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model each number n as having a 1/log(n) chance of being prime

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then find the expected number of primes

bold hemlock
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Also

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It has to be of form 6k+5

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Because modulo

bold hemlock
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I mean

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n^n+2 because the form of the number

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and ln(n) because prime number theorem

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?

high goblet
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ultimately it doesn't really matter too much cus this is just a heuristic that says there's probably only finitely many of them

bold hemlock
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Also we should sum from like n=10000

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Or something

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I mean it was checked for first 3000 primes

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Ye wolfram is not enough

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LOL

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But we probably can something that "statisticly around 0,01 of a number is prime" lol

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I mean it probably is lower than that

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But like what's the point of heuristic arguments like that?

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We know that n^n+2 is not random

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LOL

radiant jasper
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im in grade 9

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yall

high goblet
radiant jasper
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pleasure to meet you mathematicians

still geode
acoustic nova
ornate blade
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and not professional researchers

radiant jasper
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but im buns

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clazz is always boring bc its js stuff i know

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so ion like class

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tbh

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the teacher gives us friggin packets

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its unbearable

ornate blade
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maths can be fun

radiant jasper
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ya its so buns

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i love math but whatever we're learning in class sucks

iron terrace
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what are you learning

radiant jasper
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we are doing scale factor

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it sucks

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i hate it

trim vortex
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does anyone have resources on how I can prepare for the AMC12

radiant jasper
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the actual calculation is nice, the concept it easy to grasp. its just the explaining

iron terrace
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oh like dilations and stuff?

radiant jasper
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im in ninth grade 😭

iron terrace
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why are you still learnign that in 9th grade

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that's like 7th grade stuff

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no offense ofc

radiant jasper
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i dont know, the curriculum here in canada is different

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winnipeg to be specific

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i do logs

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πŸ’€

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im joking

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but i attempted to learn logarithms, i was trying some exponential equations that utilise in natural logs and whatever

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yeah i know im annoying, math js excites me

sleek ravine
sleek ravine
iron terrace
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i wasn't trying to be mean

ornate blade
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people here come from all over the world yeah

ornate blade
radiant jasper
ornate blade
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then are you asked to find the real-life area of something on the map?

radiant jasper
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yes

ornate blade
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damn okay you're doing IGCSE confirmed

radiant jasper
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i dont know what that is lolzers

ornate blade
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oh interesting

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that's what 9th and 10th graders study in the UK + many international schools

ornate blade
radiant jasper
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yez

ornate blade
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also like keep the ratio order the same, so large/small for both, or small/large for both

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yeah

ornate blade
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like you know a cube has three lengths being multiplied right

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length * width * height

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so all 3 get multiplied or divided by the length ratio

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that's why it's ^3

radiant jasper
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indeed indeed

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cubic

ornate blade
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nice

ornate blade
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for your maths in school

radiant jasper
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hell yah

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ty

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LMAOOO

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we arent learning this

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its too advanced for the ppl in my classroom

ornate blade
ornate blade
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think you might enjoy it though if you have any free time

radiant jasper
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yes lolzz, i am looking forward towards it

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this one girl in my class is doing piece-wise functions

ornate blade
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yeah that's like precalc

radiant jasper
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yes

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i do pre cal

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early

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im taking IB

ornate blade
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all of this maths you learn in school comes really handy for contest maths also

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if you don't know a broad range of topics for your year level

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you won't even get half the questions right

ornate blade
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to be fair competition problems are hard in their own way

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but people ask how do I get better at the AMC? what should I study?

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a lot of maths is freely accessible online

radiant jasper
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whats AMC?

ornate blade
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that's why I point students towards the UK curriculum

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IGCSE then A level mathematics

ornate blade
radiant jasper
ornate blade
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first round of olympiads

radiant jasper
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hey, i think you should give me a hard math problem fs

ornate blade
radiant jasper
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what continent are you in?

ornate blade
maiden panther
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if you are excited about math i think you will enjoy AMC

radiant jasper
ornate blade
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πŸ‡¦πŸ‡Ί βœ…

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πŸ‡³πŸ‡Ώ ❌ btw

radiant jasper
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its like australaisa i believe i learnt that

ornate blade
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we should be together with all the Pacific islands

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only makes sense

radiant jasper
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yes

ornate blade
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Aus + NZ + all these islands = Oceania

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then that makes us a real continent

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a real continent hidden under the sea for large parts

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(Zealandia is the 8th largest continent, cause a lot got sunk over and only New Zealand and a few other islands remain)

radiant jasper
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ohhhhhh

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i had this friend

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who moved to asia

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he was talking about the continents but he didnt include oceania 😭

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thats js amazing

radiant jasper
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i am setting up my parameters

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the center of each smaller circle lies on the circumference of the larger circle

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this looks like that one maths problem i did

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but its different bc it had

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this means that the distance from the center of the large

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r

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circle to the

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center of any smalelr circle is simply gna be R (radius of the larger circle)

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and each smaller circle has a radius of r (each smaller circle)

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do i need to

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oh wait nvm

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bro how do i get the relationship between R and r 😭

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@ornate blade sorry for pimg

radiant jasper
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whats the answer

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can we play hot or cold

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is the answer between 5 and 9

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wait

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idk

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😭

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R = r + r(sqrt(2)/2)

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R^2 = r^2(1 + sqrt(2)/2)^2

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squaring sides

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ya i aint doing ts

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fck it

topaz mist
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I want to know the answer too now 😭

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What's weird is that there are 4 small circles that are useless

bold hemlock
pearl holly
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Sup

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How do you guys increase your stamina in solving problems?

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I just solved a really hard problem and my stamina got drained

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It was this problem in NT/Prealg thata drained it haha

pallid tundra
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ah an alcumus question

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not often that we get those

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that sounds odd, are you sure you didn't just level up or smth

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and/or are you possibly confusing this for your "accuracy" stat

pearl holly
hushed charm
#

is it harder or something like that then other curriculums?

quick frost
# ornate blade enjoy suffering

Let radius = r. ||Radius of smaller circle is cr where c = 1/sqrt(2). Area of intersection = area of two sectors - area of two triangles. Angles subtended at the centres = 4 arcsin(c/2), 2 arccos(c/2) = 4 t, pi - 2t, say. So area of intersection = r^2/2 (4 t + (pi-2t) c^2) - r^2 sin(2t) = r^2 (2t + (pi/4-t/2) - 2 sqrt(7)/8) = (3t/2+ pi/4 - sqrt(7)/4) r^2. So pi r^2 - 4(that) = (pi - 6t - pi + sqrt(7)) = (sqrt(7) - 6t) r^2 = 48pi||. I give up (and this is probably terribly wrong too).

spark minnow
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If anyone has any ways on how to self study calculus please let me know thanks

pallid tundra
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wrong channel, and why haven’t you looked for any yourself first?

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!da2a

scarlet rootBOT
#

No need to ask β€œCan I ask…?” or β€œDoes anyone know about…?”—it’s faster for everyone if you just ask your question! See https://dontasktoask.com/

deft wraith
deft wraith
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Doesn’t need lots of theory to solve the questions

hushed charm
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sure

chrome parrot
#

Competition math, huh? Find every x:
√x + x = x^2

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Which numbers solve this equation?
x^3 - 2x = x

primal cosmos
#

guys im 8th grader what should i use to study for amc 12 i can only get 40

pallid tundra
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there’s no depth or sophistication needed to solve this at all

maiden panther
radiant jasper
#

vs flying_fly

maiden panther
#

who do you trust more

radiant jasper
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idk humans are better

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lol 😭

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ai is under dev

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so its hard to deicde with 4 diff answers

hushed charm
maiden panther
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it's $\sqrt{\frac{48\pi}{\sqrt7 - 6\sin^{-1}\left(\frac{\sqrt2}{4}\right)}}$

gilded haloBOT
#

flying_fly

maiden panther
pallid tundra
scarlet rootBOT
# radiant jasper

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

pallid tundra
#

if you need an online calculator to check your work just fucking use wolframalpha or smth not this ai slop nonsense 😭😭

vestal grove
#

is anyone here

ornate saffron
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yes

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no

ornate blade
ornate blade
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it's probably the best organised curriculum among all Anglophone countries
well not many people know about the Irish Leaving Certificate, or New Zealand's NCEA which are also solid

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those may be a bit harder to find materials that are not provided by the exam board

pearl holly
pallid tundra
#

you're doing yourself a MASSIVE disservice.

pearl holly
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Let me clarify

when it comes to the answer/solving part, I just let it explain the solution to me

It's where I either got a correct/incorrect ans to a problem

pallid tundra
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it doesn't actually know what it's doing

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it's just "hmm what do i think is the next word" :clueless:

pearl holly
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At this point, I don't even know what PhD people do with o1 to help them with these sort of stuff

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Can we come to an agreement that everybody has their own form of preferences?

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Whether ai or not haha

ornate blade
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they consult books and papers!
they ask their fellow students, or arrange to meet with their supervisor!

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they always have sources based on real experience and knowledge, and not something generated by a predictive text algorithm which can't tell you where it got that exact info from
(AI is famous for hallucinating and generating made-up references)

pearl holly
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Ahh, I see

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Then its best to stick with learning from solution given problems

ornate blade
#

there's always real people and materials that real people have written

pallid tundra
#

gpt is HILARIOUSLY bad at anything even slightly beyond the surface level

ornate blade
#

all my profs and lecturers said that GPT sucks balls at writing essays

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it doesn't really know how to answer a question and tailor its knowledge, or to write an extended response

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it just rambles about the general ideas that the question touches upon

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which is why AI search is good if you want to get a surface level understanding, a summary

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but it sucks for anything any deeper

swift imp
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Just ask this discord server for help is better than ai

pearl holly
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Alright, thanks!

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Alright chat, I need clarifications

Let p = prime

What is the largest prime factor of p!

Would it be p itself?

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Oh, nvm, I have made the correct assumption

pallid tundra
#

yea lol

acoustic nova
#

bruh

hushed charm
#

Besides that. gpt does not have any kind of creativity or problem-solving skills, he is just going always to opt for solutions way harder than should be and brute forcing operations with massive numbers

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Like this question, I remember asking for chatgpt how to solve this problem and he always tried to compute 2024Β³, dividing stuff by 2024Β³

Let x and y be real numbers such that x + y = 2024 and xy = 8. If

1/xΒ³ + 1/yΒ³ = p/q,

where p and q are positive integers that are coprime, what is the remainder of p - q when divided by 5?

(A) 0 (B) 1 (C) 2 (D) 3 (E) 4

summer roost
#

And it gave me some calculus solution

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Which I cannot even verify

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Here is the question

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Prove that

gilded haloBOT
#

Triaengle

summer roost
obsidian herald
scarlet rootBOT
obsidian herald
#

hint: ||use binomial expansion, then manipulate the terms a bit to get the term in the expansion of another binomial||

summer roost
#

I need to find where I solved a question, I will open a help channel

tough patrol
#

could we try induction?

obsidian herald
hushed charm
sleek ivy
#

Huh

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Prolly cuz i was too lazy to check if the fraction was in simplest form

umbral dock
tepid surge
#

we know that $\frac{1}{x^3} + \frac{1}{y^3} = \frac{x^3 + y^3}{(xy)^3}$

gilded haloBOT
#

hiidostuff

tepid surge
#

well maybe youve already solved it

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idk

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then we have that $x^3 + y^3 = (x + y)^3 - 3xy^2 - 3x^2y = (x + y)^3 - 3xy(x + y)$

gilded haloBOT
#

hiidostuff

hushed charm
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Yeah, that is how I solved it

tepid surge
#

nice

hushed charm
#

Is this called polynomial symmetry?

tepid surge
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well

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the type of polynomial tricks youre using is due to the fact that everything expands to a symmetric polynomial

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a symmetric polynomial is a polynomial of x_1, x_2, ... x_n that remains the same no matter how you permute the variables

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so for example, x^3 + y^3 = y^3 + x^3

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turns out that every symmetric polynomial of x,y can be expressed in terms of simpler elements of x and y

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that being (x + y) and xy

hushed charm
#

awesome

pallid tundra
#

shameless self promotion time

soft vigil
#

1/x+1/y=2024/8 and 1/xy=1/8

hushed charm
#

I can show if you want

hollow rose
#

Anyone here done the euclid?

tepid surge
#

each term in the numerator is divisible by 8 so p/q is an integer

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then (2024)^3 / 8 = (1012)^3 which is 3 mod 5

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then 3(8)(2024)/8 = 3(2024) which is congruent to 2 mod 5

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wait i mightve screwed up

maiden panther
#

it's 129553457/8

tepid surge
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no wait it is A

soft vigil
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Im getting A

maiden panther
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how?

tepid surge
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and p/q is an integer

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therefore its A

maiden panther
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bruh

soft vigil
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I get denominator is 3 mod 5

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Specifically it is 8

tepid surge
soft vigil
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What

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Is it not p-q

tepid surge
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i should say, when you reduce the rational expression, the numerator is 1 mod 5

soft vigil
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I get that p/q=11232021/8

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Numerator 3 mod 5

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Denominator 3 mod 5

tepid surge
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it cant be odd on top

soft vigil
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Why

tepid surge
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you should get $\frac{(2024)^3 - 3(8)(2024)}{8}$

gilded haloBOT
#

hiidostuff

soft vigil
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Wait a sec

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I might be wrong

tepid surge
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you are

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the numerator must be even

soft vigil
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Oops yeag

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Accidentally squared

tepid surge
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its ok tho

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from here the problem is pretty easily solvable

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firstly, reduce the expression

soft vigil
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Yes of course

tepid surge
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to get $\frac{(1012)^3 - 3(2024)}{1}$

gilded haloBOT
#

hiidostuff

soft vigil
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The problem itself is not hard

tepid surge
#

then 1012^3 is 3 mod 5

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3(2024) is 2 mod 5

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so 1 mod 5 on top of 1 mod 5

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0 mod 5

maiden panther
#

divide by 512

chrome parrot
#

Which numbers work for
2^n - 3 = prime number?
(finite answer)

pearl holly
gilded haloBOT
pearl holly
#

frick my punctuation is bad

chrome parrot
#

Try so, there is a finite amount of numbers

pearl holly
#

Is there some kind of constraint?

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like 3 < n < 9999?

chrome parrot
#

There are several numbers which, when used, you get a prime number

#

1 < n < 100

#

In that area

pearl holly
#

Oh, then, its just {3,5}

#

Oh, wait

#

nv,

#

I just brute forced it and disregarded the prime numbers for n

#

My bad

pearl holly
gilded haloBOT
pearl holly
#

Why did my brain think that the bold text thing whould work for TeXit

chrome parrot
#

Not only

pearl holly
#

What do you mean?

chrome parrot
hushed charm
#

$\frac{1}{x^3} + \frac{1}{y^3} = \frac{p}{q} \Rightarrow \frac{x^3 + y^3}{(xy)^3} = \frac{p}{q} \Rightarrow \frac{(x + y)^3 - 3xy(x + y)}{512} = \frac{p}{q} \Rightarrow \frac{2024^3 - 24 \cdot 2024}{512} = \frac{p}{q} \Rightarrow \frac{2024(2024^2 - 24)}{2^9} = \frac{p}{q} \Rightarrow \frac{253(2^6 \cdot 253^2 - 8 \cdot 3)}{2^6} = \frac{p}{q} \Rightarrow \frac{253 \cdot 2^3(2^3 \cdot 253^2 - 3)}{2^6} = \frac{p}{q} \Rightarrow \frac{253(2^3 \cdot 253^2 - 3)}{2^3} = \frac{p}{q}$

gilded haloBOT
#

samuel

hushed charm
#

$p = 253(2^3 \cdot 253 - 3) \quad \text{and} \quad q = 8 \Rightarrow 253(2^3 \cdot 253 - 3) \bmod 5 = 3(3 \cdot 4 - 3) = 2 \quad \text{and} \quad 8 \bmod 5 = 3 \Rightarrow 2 - 3 = -1 \Rightarrow -1 \bmod 5 = 4$

gilded haloBOT
#

samuel

wise cape
#

$p = 253(2^3 \cdot 253 - 3) \quad \text{and} \quad q = 8 \Rightarrow 253(2^3 \cdot 253 - 3) \bmod 5 = 3(3 \cdot 4 - 3) = 2 \quad \text{and} \quad 8 \bmod 5 = 3 \Rightarrow 2 - 3 = -1 \Rightarrow -1 \bmod 5 = 4$

gilded haloBOT
#

yangbegeflex

$p = 253(2^3 \cdot 253 - 3) \quad \text{and} \quad q = 8 \Rightarrow 253(2^3 \cdot 253 - 3) \bmod 5 = 3(3 \cdot 4 - 3) = 2 \quad \text{and} \quad 8 \bmod 5 = 3 \Rightarrow 2 - 3 = -1 \Rightarrow -1 \bmod 5 = 4$
wise cape
#

$x^3 + y^3 = (x + y)^3 - 3xy^2 - 3x^2y = (x + y)^3 - 3xy(x + y)$

gilded haloBOT
#

yangbegeflex

wise cape
#

dude this cool

gilded haloBOT
#

loremz

#

loremz

#

loremz

keen ingot
#

nice

obsidian herald
obsidian herald
#

otherwise, you may try approach0 to search that

tulip coral
#

I want to prepare for Math competitions

#

But I don’t have a routine

#

Any recommendations?

#

For Summer.

soft vigil
#

aops books to beginwith

tulip coral
#

Any online resource?

#

For free?

soft vigil
#

idk

#

aops books r always good

tulip coral
#

I have a study strategy that might help

#

Active recall strategy

soft vigil
#

i know aops has those free like

#

mathcounts minis

tulip coral
#

Online practice or YouTube

soft vigil
#

idk

#

theres lots

#

theres mathdas

#

amctrivial

tulip coral
#

Ok

tulip coral
soft vigil
#

juust start one and stick to it

tulip coral
#

In algebra 2

#

Im taking summer classes for calc

soft vigil
#

shouldnt you learn precalc first πŸ’€

tulip coral
soft vigil
#

alsocalc does not matter for comp math

tulip coral
#

That’s what I mean

tulip coral
soft vigil
#

comp math matters ig

#

geo is important

tulip coral
soft vigil
#

its rly different than school math

tulip coral
#

I think it’s helpful

soft vigil
#

pickup like aops volume 1

safe oriole
#

are amc questions good for other olympiads

soft vigil
#

im not condoning this but you may or may not be able to find the books free online

safe oriole
#

like which amc questions should i start with

soft vigil
#

amc is good if you are in the USA

tulip coral
#

See how others practice

safe oriole
#

ok

tulip coral
#

Understand the topics

#

Than solve

#

It on your own

soft vigil
#

yes thats the strat

#

for basically everything in math

tulip coral
#

Yeah

safe oriole
#

thanks

warm mantle
#

Yo can anyone help with this problem? Let ABC be a triangle in which we have drawn the median BE from vertex B, and a segment that goes from C to a point D on side AB. This point D can slide along side AB.

The intersection point of both segments is point F.

We call p the ratio between the segments into which D divides side AB, q the ratio between the segments into which F divides the median BE, and r the ratio between the segments into which F divides CD.

What will be the ratio between triangle CEF and triangle FDB for any value of p?

#

I'm pretty sure it's pr/2 but I don't know how to prove it?

warm mantle
tulip coral
#

….

#

I need the question

tulip coral
#

Ok

#

I honestly don’t know where to start.

#

Wait

#

So

warm mantle
#

The only thing I know from previous parts of the exercise is that r = p+1

tulip coral
#

I know we’re told that

#

CF/FD IS 7

#

So

#

If the triangles

#

Share the same height, the ratios of their areas is the ratio of their bases.

#

That being said

#

Yeah

#

I might need more info

#

Are you sure this is the question?

warm mantle
#

Yes, it is. Maybe you have to do it through Menelau's theorem, the other parts of the exercise were done with that

tulip coral
#

Ok

warm mantle
#

Also, BF Γ— AD = 2 Γ— FE Γ— BD if that helps

tulip coral
#

Yeah thanks

#

Im reading the theorem to refresh memory

#

I just need heights and

#

Other ratios

#

Knowing AD/DC doesn’t help me determine the other segments

#

@warm mantle

warm mantle
#

So the problem doesn't say anything about the heights or the other ratios, but maybe you can find an auxiliary point parallel to AE in the FDB triangle and then say CEF is congruent to FDX and maybe something with that afterwards idk

tulip coral
#

Never

#

Mind

#

I see

#

What I need to do

warm mantle
#

Ok

tulip coral
#

@warm mantle

#

Is it 126

#

Tell me where you found the problem

warm mantle
#

It's a website in Spanish

#

It doesn't say the answer

#

I dont have the link but I can send screenshots

#

It's the 9th question

tulip coral
#

Oh

pallid tundra
#

mass points

obsidian herald
#

.

ornate blade
#

<@&268886789983436800> here too

gilded haloBOT
hushed charm
#

<@&268886789983436800>

radiant jasper
#

who does math and code at the same time in lua

#

hopefully, sending files like these isnt a violation. its like vector mathematics in lua, its a simple module and i plan on integrating quaternions

#

if its a violation then the mods can delete this

sullen tapir
#

using roblox as a refence lol

hushed charm
#

But here isn't really the perfect channel to send that, focus on olympic maths here

radiant jasper
radiant jasper
#

And I lost πŸ’”

obsidian herald
#

I revisited an old post: #1190382943663816756 message
Actually, L3435 showed a simple proof by rearrangement inequality in AoPS: https://artofproblemsolving.com/community/c6h1712301p11047177
The strategy is to start by homogenization of the given inequality using the constraint.
Inequality's LHS degree = -1
Inequality's RHS degree = 1
so use the "degree 2 = degree 0" equality constraint to raise inequality's LHS degree by 2 (by multiplying by "1")

balmy spoke
#

theta real -2pi < theta <2pi

#

(please tag me)

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

1

ivory ember
#

but as a hint, consider $(\cos \theta+\sin \theta)^2$

gilded haloBOT
#

Civil Service Pigeon

balmy spoke
#

$(\sin\theta+3\cos\theta)^2=0=\sin^2\theta+6\sin\theta\cos\theta+9\cos^2\theta$

gilded haloBOT
balmy spoke
#

,tex \sin^2\theta+9\cos^2\theta&=-3\sin2\theta \ (\sin\theta+\cos\theta)^2-2\sin\theta\cos\theta+8\cos^2\theta&=-3\sin2\theta \ (\sin\theta+\cos\theta)^2&=-3\sin2\theta+\sin2\theta-8\cos^2\theta \ \therefore\sin\theta+\cos\theta&=\sqrt{-2(\sin2\theta+4\cos^2\theta)}

gilded haloBOT
#

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

balmy spoke
#

can i say this?

#

Recall that $\theta$ is a real number, then $\sin\theta + \cos\theta \in \mathbb{R}$. By contradiction, if $\sin2\theta+4\cos^2\theta$ is non-negative, then $\sin\theta + \cos\theta$ is part of the complex plane, which is not possible. Hence, \underline{\underline{$\sin2\theta+4\cos^2\theta\leq0$}}.

gilded haloBOT
ivory ember
#

I was intending for you to consider $(\sin \theta +\cos \theta)^2$ in general

gilded haloBOT
#

Civil Service Pigeon

ivory ember
balmy spoke
#

):

#

how would you word it

ivory ember
#

Since $\theta$ is real, $\sin \theta+\cos \theta$ must also be real. Hence, $\sqrt{-2(\sin 2\theta+4\cos^2 \theta)}$ must also be real, which implies that $$-2(\sin 2\theta+4 \cos^2 \theta) \geq 0$$ $$\sin 2 \theta+4\cos^2 \theta \leq 0$$

gilded haloBOT
#

Civil Service Pigeon

ivory ember
#

cause the part about "is part of the complex plane" is a bit iffy

#

just say it's non real if you're gonna say that

ivory ember
gilded haloBOT
#

Civil Service Pigeon

balmy spoke
maiden panther
#

maybe i'm missing something but what is the point of the expression at the top

#

and what is part ii even saying

ivory ember
gilded haloBOT
ivory ember
#

,w sin x + 3 cos x, x = pi

gilded haloBOT
ivory ember
#

take that as you will

ivory ember
gilded haloBOT
#

Civil Service Pigeon

ivory ember
balmy spoke
#

yep thank you pigeon

ivory ember
balmy spoke
#

i think i remember you

#

from like 2 years ago

#

got to national and scored a zero hahaha

#

im proud of it tho

ivory ember
gilded haloBOT
#

Civil Service Pigeon

ivory ember
#

so maybe they just want you to find the value of this in the case where it's non negative

#

and they're calling that alpha

#

not my favorite wording

#

in which case it would be ||sqrt(2/5)||

maiden panther
#

i may be missing something, but doesn't $\sin\theta + 3\cos\theta = 0$ already imply $\cos^2\theta = \frac{1}{10}$?

gilded haloBOT
#

flying_fly

ivory ember
ivory ember
#

there's a few ways that you can do this

#

but I doubt that they intended for you to just bash out the value of the expression explicitly

ivory ember
balmy spoke
#

πŸ‘‰ πŸ‘ˆ

maiden panther
ivory ember
#

I did say this lol

balmy spoke
maiden panther
#

like, why is there a 4 in part ii if it's just saying the ratio is nonnegative

balmy spoke
#

what are you aiming to join next

ivory ember
#

it's giving the sat/jee just adding extra stuff for no reason

maiden panther
#

fr

sand river
#

guys I solved an olympiad number theory problem

#

🀯

tulip coral
soft vigil
balmy spoke
glossy pawn
#

Dm the solution

keen pelican
radiant jasper
sand river
#

ok

hushed charm
#

Guys

#

What are your opinions on khan academy vs aops books? I am currently reading introduction to algebra by aops, I really like it but some people prefer khan academy, what do you think?

pallid tundra
#

apples to oranges

#

my opinion of KA has considerably degraded over the years

pallid tundra
#

its coverage of the material is far too surface level

#

it's like if you wanted to sparknotes middle and high school math without any of the underlying rigor

#
  • not enough exercises for a lot of the topics (especially for AP calc)
#

and their whole chatgpt enshittification

hushed charm
#

alright, that makes sense

sand river
#

aops books are great, but solving previous years competition problems and then learning what you dont know through other online resources is great too

#

but aops books are good for introduction

hushed charm
#

What other online resources do you like?

sand river
#

Previous tests like amc, aime, usamo, bmo, tournament of towns, and others are good

#

youtube has many good courses that are useful and free

#

some previous olympiad medalists or coaches have websites

hushed charm
#

Indeed, organic chemistry channel has saved me a lot

#

yeah

#

the only one I know is evan chen's

sand river
#

this guy has a really great channel

hushed charm
#

Interesting, going to check his videos later

#

Are you studying for math olympiads either?

pallid tundra
tulip coral
#

Anyone knows a good site to review limits?

sand river
tulip coral
sand river
#

yes

tulip coral
sand river
#

good

tulip coral
#

I want information

#

On another person’s experience.

#

With Olympiad

sand river
#

I have been practicing previous years

#

and so far it's going well

#

Im able to solve much more problems than I used to be able to

#

especially with things like geometry which used to be by far my worst subject

tulip coral
#

Hopefully you suceed.

hushed charm
pallid tundra
#

his channel is like

#

remedial math

#

not the kind you need for contests

pallid tundra
#

neither are particularly deep or difficult

hushed charm
#

But like, his short videos can help a little with some introductions to new subjects and remember some other subjects

#

Usually when I forger something kinda easy, his videos helped me

#

but indeed, he doesn't show a lot of problems

hushed charm
pallid tundra
#

it's the "quality"

#

he only covers the most basic trivial plug and chug examples

#

if you need it to pass your standard algebra 2 math test it's probably fine

#

if you need to do anything slightly more substantial

#

hell no

hushed charm
#

Indeed studying only with his channel isn't a good idea

hushed charm
sleek ivy
#

is it just me or is aops website the slowest thing ever

sand river
tulip coral
#

I was in a similar situation.

spark gorge
#

is anyone here participating in ARML local this year? i have some clarification questions about the event

hazy reef
#

im in 8th grade and doing some comp math and soon one of my math classes will end

#

any suggestions for another math curriculum or class u would recco

#

i alr do aops

#

and some other classes

wooden ice
#

Guys i need help understanding this

#

i already know the answer

#

it's kangaroo math 2024

hazy reef
#

can u translate to english

ionic smelt
#

if I understood the question, i'm honestly bad at french

wooden ice
#

yup that is correct but how did you get it knowing that they both have opposite directions and we dont even know the pace in which they make a turn, since its freely

ionic smelt
wooden ice
# hazy reef can u translate to english

yes sure
Two hexagons with the same center, one with letters and the other with numbers, can rotate freely around their center. In the figure, the letter F is next to 6. Which letter will be next to 1 when the F is next to 3?

ionic smelt
#

Thus:
3 - 2 - 1
F - E - D

#

1 corresponds to D

hazy reef
#

so just find what is 2 counterclockwise to F

wooden ice
#

1 is 2 counterclockwise?

hazy reef
#

directions of turns dont matter

hazy reef
wooden ice
#

yeah

#

ah

#

but how did u think that it should be counterclockwise

#

or either

ionic smelt
wooden ice
#

yeah

ionic smelt
#

Imagine a clock with only 6 hours

wooden ice
#

yes i get it

ionic smelt
#

alr

wooden ice
#

but if they turn at the same time its not possible right

wooden ice
#

saf i got it thx

#

thanks!

#

What about this one guys

ionic smelt
#

please translate it

wooden ice
#

lol

ionic smelt
#

my french is horrible

wooden ice
#

gpt 4 doesnt work for me idk where i should translate it

#

cuz i already used it

ionic smelt
#

use google translate

wooden ice
#

can u use it? like send it the pic and tell it to translate it for u

#

how? with pic?

#

i cant copy paste

#

its kangaroo

#

olympiad

ionic smelt
#

oh it's pic

#

rip

wooden ice
#

lol

#

u have gpt

ionic smelt
#

i don't pay

wooden ice
#

me neither

#

but its free

ionic smelt
#

oh then i'll try

wooden ice
#

for limited time

#

ya

ionic smelt
#

ok

#

Six packages are placed on the platform of a truck. Manu unloads them to place them on the ground. He takes one package at a time and only if there isn’t another package on top of it. He places it either on the ground or stacks it on top of those already placed, and he won’t move it again.

Which of these stackings could not be obtained by Manu?

#

hmm... lemme think

#

hell nah D is sus as hell

wooden ice
#

yay

ionic smelt
#

because 2 is stacked below 4

#

which is impossible unless you are a magician

wooden ice
#

whaa

#

really

#

how

ionic smelt
#

yea it's D

#

as you see, 4 can't be stacked on top of 2

wooden ice
#

wait only now i got it

#

i didnt know that the pic at the right was in the camion

#

lol

ionic smelt
#

yea

wooden ice
#

he took em from here

ionic smelt
wooden ice
#

ok yea makes sense

wooden ice
ionic smelt
#

lmao

wooden ice
#

why

ionic smelt
# wooden ice why

because neither of us were understanding the question at first instance

#

lol

wooden ice
#

no but i understand french really well

ionic smelt
#

ohh

wooden ice
#

im on this question now

#

how do we calculate the perimiter

#

or idk how to spell it

#

peremiter

#

?

#

of the gray part

ionic smelt
#

well first of all i think it says that the white parts are square

#

if i understood it correctly

wooden ice
#

yes

#

benjamin cut those white squares

#

2 3 6 and 1 cm

#

ok i see that its 36 cm perhaps

ionic smelt
#

wait lemme see

wooden ice
#

cuz 40 is of the whole square

#

and smaller than 40 is only 36

#

the only option

ionic smelt
#

yea but it's easily calculable

wooden ice
#

which doesnt make sense?

#

yea go on

ionic smelt
#

in the perimeter you have at least 3+3 (2 sides of the 3x3 square), 6+6 (2 sides of the 6x6 square), 1+1 (yea u understand it) and 2+2

wooden ice
#

yes

ionic smelt
#

and then you have 10-3-2=5 on top, 10-3-6=1 on right, 10-6-1=3 bottom and 10-2-1=7 left

ionic smelt
wooden ice
#

oh?

ionic smelt
#

so you have 6+12+2+4+5+1+3+7 which gives you 36

wooden ice
#

niice

soft vigil
sand river
#

here I have another problem today:

soft vigil
#

why is this so familiar

spark gorge
# tulip coral Hm

for the ARML Local, are teams supposed to find the nearest school that is competing in or is every school team supposed to host the competition at their school?

soft vigil
#

if there is no nearby site then just get like a parent to host it

#

thats what happened in chicago at least\

wooden ice
#

Ok guys they said 3 identical cubes are on a table, what is the sum of the 3 numbers written on the faces that we put on the table.

#

is it a b c d or e

summer roost
#

A general method might be to find the opposite faces

#

That might be slow but works all the time

#

Which competition is it ??

ionic smelt
#

by the second cube you see that beneath 8 is 13, by the third cube you see that beneath 13 is 22 and by the third cube you see that beneath 22 is 8

ionic smelt
#

it's C

karmic rune
# wooden ice

unfold the cubes, somewhat like this and check which numbers are adjacent and which are opposite. If you do it properly, you can solve the problem easily