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k a May Highlights and 2025 AoPS Online Class Information
jlacosta   0
Yesterday at 11:16 PM
May is an exciting month! National MATHCOUNTS is the second week of May in Washington D.C. and our Founder, Richard Rusczyk will be presenting a seminar, Preparing Strong Math Students for College and Careers, on May 11th.

Are you interested in working towards MATHCOUNTS and don’t know where to start? We have you covered! If you have taken Prealgebra, then you are ready for MATHCOUNTS/AMC 8 Basics. Already aiming for State or National MATHCOUNTS and harder AMC 8 problems? Then our MATHCOUNTS/AMC 8 Advanced course is for you.

Summer camps are starting next month at the Virtual Campus in math and language arts that are 2 - to 4 - weeks in duration. Spaces are still available - don’t miss your chance to have an enriching summer experience. There are middle and high school competition math camps as well as Math Beasts camps that review key topics coupled with fun explorations covering areas such as graph theory (Math Beasts Camp 6), cryptography (Math Beasts Camp 7-8), and topology (Math Beasts Camp 8-9)!

Be sure to mark your calendars for the following upcoming events:
[list][*]May 9th, 4:30pm PT/7:30pm ET, Casework 2: Overwhelming Evidence — A Text Adventure, a game where participants will work together to navigate the map, solve puzzles, and win! All are welcome.
[*]May 19th, 4:30pm PT/7:30pm ET, What's Next After Beast Academy?, designed for students finishing Beast Academy and ready for Prealgebra 1.
[*]May 20th, 4:00pm PT/7:00pm ET, Mathcamp 2025 Qualifying Quiz Part 1 Math Jam, Problems 1 to 4, join the Canada/USA Mathcamp staff for this exciting Math Jam, where they discuss solutions to Problems 1 to 4 of the 2025 Mathcamp Qualifying Quiz!
[*]May 21st, 4:00pm PT/7:00pm ET, Mathcamp 2025 Qualifying Quiz Part 2 Math Jam, Problems 5 and 6, Canada/USA Mathcamp staff will discuss solutions to Problems 5 and 6 of the 2025 Mathcamp Qualifying Quiz![/list]
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0 replies
jlacosta
Yesterday at 11:16 PM
0 replies
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k i Adding contests to the Contest Collections
dcouchman   1
N Apr 5, 2023 by v_Enhance
Want to help AoPS remain a valuable Olympiad resource? Help us add contests to AoPS's Contest Collections.

Find instructions and a list of contests to add here: https://artofproblemsolving.com/community/c40244h1064480_contests_to_add
1 reply
dcouchman
Sep 9, 2019
v_Enhance
Apr 5, 2023
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k i Zero tolerance
ZetaX   49
N May 4, 2019 by NoDealsHere
Source: Use your common sense! (enough is enough)
Some users don't want to learn, some other simply ignore advises.
But please follow the following guideline:


To make it short: ALWAYS USE YOUR COMMON SENSE IF POSTING!
If you don't have common sense, don't post.


More specifically:

For new threads:


a) Good, meaningful title:
The title has to say what the problem is about in best way possible.
If that title occured already, it's definitely bad. And contest names aren't good either.
That's in fact a requirement for being able to search old problems.

Examples:
Bad titles:
- "Hard"/"Medium"/"Easy" (if you find it so cool how hard/easy it is, tell it in the post and use a title that tells us the problem)
- "Number Theory" (hey guy, guess why this forum's named that way¿ and is it the only such problem on earth¿)
- "Fibonacci" (there are millions of Fibonacci problems out there, all posted and named the same...)
- "Chinese TST 2003" (does this say anything about the problem¿)
Good titles:
- "On divisors of a³+2b³+4c³-6abc"
- "Number of solutions to x²+y²=6z²"
- "Fibonacci numbers are never squares"


b) Use search function:
Before posting a "new" problem spend at least two, better five, minutes to look if this problem was posted before. If it was, don't repost it. If you have anything important to say on topic, post it in one of the older threads.
If the thread is locked cause of this, use search function.

Update (by Amir Hossein). The best way to search for two keywords in AoPS is to input
[code]+"first keyword" +"second keyword"[/code]
so that any post containing both strings "first word" and "second form".


c) Good problem statement:
Some recent really bad post was:
[quote]$lim_{n\to 1}^{+\infty}\frac{1}{n}-lnn$[/quote]
It contains no question and no answer.
If you do this, too, you are on the best way to get your thread deleted. Write everything clearly, define where your variables come from (and define the "natural" numbers if used). Additionally read your post at least twice before submitting. After you sent it, read it again and use the Edit-Button if necessary to correct errors.


For answers to already existing threads:


d) Of any interest and with content:
Don't post things that are more trivial than completely obvious. For example, if the question is to solve $x^{3}+y^{3}=z^{3}$, do not answer with "$x=y=z=0$ is a solution" only. Either you post any kind of proof or at least something unexpected (like "$x=1337, y=481, z=42$ is the smallest solution). Someone that does not see that $x=y=z=0$ is a solution of the above without your post is completely wrong here, this is an IMO-level forum.
Similar, posting "I have solved this problem" but not posting anything else is not welcome; it even looks that you just want to show off what a genius you are.

e) Well written and checked answers:
Like c) for new threads, check your solutions at least twice for mistakes. And after sending, read it again and use the Edit-Button if necessary to correct errors.



To repeat it: ALWAYS USE YOUR COMMON SENSE IF POSTING!


Everything definitely out of range of common sense will be locked or deleted (exept for new users having less than about 42 posts, they are newbies and need/get some time to learn).

The above rules will be applied from next monday (5. march of 2007).
Feel free to discuss on this here.
49 replies
ZetaX
Feb 27, 2007
NoDealsHere
May 4, 2019
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9 What language do you take
LXC007   2
N 2 minutes ago by ZMB038
In my school pretty much all the math people take latin. I was wondering if this is the case for others as well. At my school we have Spanish French Chinese and Latin. I also added German and Japanese because google said it was offered in some schools
2 replies
LXC007
3 hours ago
ZMB038
2 minutes ago
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9 AMC 10 Prep
bluedino24   2
N 3 minutes ago by bluedino24
I'm in 7th grade and thought it would be good to start preparing for the AMC 10. I'm not extremely good at math though.

I feel that I am better at Mathcounts than AMC 8. I got a 41 on chapter and did not take state (I was sick), and a 20 on the AMC 8 this year. Are there any parts to AMC 8 and 10 that are special, or any strategies? What are some important topics I should study? Please comment below. Thanks! :D
2 replies
bluedino24
9 minutes ago
bluedino24
3 minutes ago
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1500th Post!
PikaPika999   49
N 15 minutes ago by ZMB038
I hit my 1500th post!!

Oh whoops I didn't know marathons were banned. Instead, ig make 24 using the following numbers:

3,3,8,8
49 replies
PikaPika999
Yesterday at 1:09 AM
ZMB038
15 minutes ago
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Purple Comet Math Meet Recources
RabtejKalra   9
N an hour ago by codegirl2013
I heard that you can take a packet of information to the Purple Comet examination with some formulas, etc. Does anybody have a copy of a guidebook with all the important formulas? I'm just too lazy to write one myself.......
9 replies
RabtejKalra
Apr 24, 2025
codegirl2013
an hour ago
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positive integers forming a perfect square
cielblue   0
an hour ago
Find all positive integers $n$ such that $2^n-n^2+1$ is a perfect square.
0 replies
cielblue
an hour ago
0 replies
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Function equation
LeDuonggg   6
N 2 hours ago by MathLuis
Find all functions $f: \mathbb{R^+} \rightarrow \mathbb{R^+}$ , such that for all $x,y>0$:
\[ f(x+f(y))=\dfrac{f(x)}{1+f(xy)}\]
6 replies
LeDuonggg
Yesterday at 2:59 PM
MathLuis
2 hours ago
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A nice and easy gem off of StackExchange
NamelyOrange   0
2 hours ago
Source: https://math.stackexchange.com/questions/3818796/
Define $S$ as the set of all numbers of the form $2^i5^j$ for some nonnegative $i$ and $j$. Find (with proof) all pairs $(m,n)$ such that $m,n\in S$ and $m-n=1$.
0 replies
NamelyOrange
2 hours ago
0 replies
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at everystep a, b, c are replaced by a+\gcd(b,c), b+\gcd(a,c), c+\gcd(a,b)
NJAX   8
N 2 hours ago by Assassino9931
Source: 2nd Al-Khwarizmi International Junior Mathematical Olympiad 2024, Day2, Problem 8
Three positive integers are written on the board. In every minute, instead of the numbers $a, b, c$, Elbek writes $a+\gcd(b,c), b+\gcd(a,c), c+\gcd(a,b)$ . Prove that there will be two numbers on the board after some minutes, such that one is divisible by the other.
Note. $\gcd(x,y)$ - Greatest common divisor of numbers $x$ and $y$

Proposed by Sergey Berlov, Russia
8 replies
NJAX
May 31, 2024
Assassino9931
2 hours ago
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Increments and Decrements in Square Grid
ike.chen   23
N 2 hours ago by Andyexists
Source: ISL 2022/C3
In each square of a garden shaped like a $2022 \times 2022$ board, there is initially a tree of height $0$. A gardener and a lumberjack alternate turns playing the following game, with the gardener taking the first turn:
[list]
[*] The gardener chooses a square in the garden. Each tree on that square and all the surrounding squares (of which there are at most eight) then becomes one unit taller.
[*] The lumberjack then chooses four different squares on the board. Each tree of positive height on those squares then becomes one unit shorter.
[/list]
We say that a tree is majestic if its height is at least $10^6$. Determine the largest $K$ such that the gardener can ensure there are eventually $K$ majestic trees on the board, no matter how the lumberjack plays.
23 replies
ike.chen
Jul 9, 2023
Andyexists
2 hours ago
J
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4-var inequality
RainbowNeos   5
N 3 hours ago by RainbowNeos
Given $a,b,c,d>0$, show that
\[\frac{a}{b}+\frac{b}{c}+\frac{c}{d}+\frac{d}{a}\geq 4+\frac{8(a-c)^2}{(a+b+c+d)^2}.\]
5 replies
1 viewing
RainbowNeos
Yesterday at 9:31 AM
RainbowNeos
3 hours ago
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Hard diophant equation
MuradSafarli   2
N 3 hours ago by MuradSafarli
Find all positive integers $x, y, z, t$ such that the equation

$$ 2017^x + 6^y + 2^z = 2025^t $$
is satisfied.
2 replies
MuradSafarli
4 hours ago
MuradSafarli
3 hours ago
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An almost identity polynomial
nAalniaOMliO   6
N 3 hours ago by Primeniyazidayi
Source: Belarusian National Olympiad 2025
Let $n$ be a positive integer and $P(x)$ be a polynomial with integer coefficients such that $P(1)=1,P(2)=2,\ldots,P(n)=n$.
Prove that $P(0)$ is divisible by $2 \cdot 3 \cdot \ldots \cdot n$.
6 replies
nAalniaOMliO
Mar 28, 2025
Primeniyazidayi
3 hours ago
J
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Euler's function
luutrongphuc   2
N 4 hours ago by KevinYang2.71
Find all real numbers \(\alpha\) such that for every positive real \(c\), there exists an integer \(n>1\) satisfying
\[ \frac{\varphi(n!)}{n^\alpha\,(n-1)!} \;>\; c. \]
2 replies
luutrongphuc
6 hours ago
KevinYang2.71
4 hours ago
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Wot n' Minimization
y-is-the-best-_   25
N 4 hours ago by john0512
Source: IMO SL 2019 A3
Let $n \geqslant 3$ be a positive integer and let $\left(a_{1}, a_{2}, \ldots, a_{n}\right)$ be a strictly increasing sequence of $n$ positive real numbers with sum equal to 2. Let $X$ be a subset of $\{1,2, \ldots, n\}$ such that the value of
\[ \left|1-\sum_{i \in X} a_{i}\right| \]is minimised. Prove that there exists a strictly increasing sequence of $n$ positive real numbers $\left(b_{1}, b_{2}, \ldots, b_{n}\right)$ with sum equal to 2 such that
\[ \sum_{i \in X} b_{i}=1. \]
25 replies
y-is-the-best-_
Sep 23, 2020
john0512
4 hours ago
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Website to learn math
hawa   72
N Yesterday at 8:18 AM by KF329
Hi, I'm kinda curious what website do yall use to learn math, like i dont find any website thats fun to learn math
72 replies
hawa
Apr 9, 2025
KF329
Yesterday at 8:18 AM
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Website to learn math
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Reveal topic tags
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hawa
2 posts
hawa
#1 h  Apr 9, 2025, 2:52 AM • 2 Y
Y by IsaacShi, EthanNg6
Hi, I'm kinda curious what website do yall use to learn math, like i dont find any website thats fun to learn math
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Leeoz
178 posts
Leeoz
#2 h  Apr 9, 2025, 2:56 AM • 18 Y
Y by huajun78, jkim0656, Sedro, Cinnamon.-.Roll, BigOrca, pingpongmerrily, acuL_51, MathDolphin95, aidan0626, Gato_combinatorio, Creeperboat, Solocraftsolo, Exponent11, nitride, megarnie, Embershed97, LawofCosine, EthanNg6
your on the right site to learn math...
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jkim0656
1009 posts
jkim0656
#3 h  Apr 9, 2025, 2:57 AM • 6 Y
Y by Cinnamon.-.Roll, BigOrca, MathDolphin95, Exponent11, Embershed97, EthanNg6
deadpan voiceover
*i use this website to learn math*.
This post has been edited 1 time. Last edited by jkim0656, Apr 9, 2025, 2:57 AM
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codeninja
75 posts
codeninja
#4 h  Apr 9, 2025, 3:01 AM • 2 Y
Y by MathDolphin95, Exponent11
Use Beast Academy (BA)
It's run by AoPS
Real fun
Link: https://beastacademy.com
This post has been edited 1 time. Last edited by codeninja, Apr 9, 2025, 3:03 AM
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jkim0656
1009 posts
jkim0656
#5 h  Apr 9, 2025, 3:04 AM • 3 Y
Y by Cinnamon.-.Roll, BigOrca, MathDolphin95
codeninja wrote:
Use Beast Academy (BA)
It's run by AoPS
Real fun
Link: https://beastacademy.com

im pretty sure it only goes up to 5th grade tho...
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kiwiteddy
346 posts
kiwiteddy
#6 h  Apr 9, 2025, 3:09 AM • 2 Y
Y by BigOrca, MathDolphin95
aops is nice, and i like khan academy too
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IsaacShi
374 posts
IsaacShi
#7 h  Apr 9, 2025, 3:19 AM • 3 Y
Y by BigOrca, MathDolphin95, GallopingUnicorn45
aops and alphastar. (aops better)
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martianrunner
191 posts
martianrunner
#8 h  Apr 9, 2025, 4:37 AM • 2 Y
Y by BigOrca, GallopingUnicorn45
you kind of have to sign up for alphastar, no?

alphastar's website doesn't really provide much learning
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sadas123
1252 posts
sadas123
#9 h  Apr 9, 2025, 10:56 AM • 3 Y
Y by BigOrca, MathDolphin95, GallopingUnicorn45
martianrunner wrote:
you kind of have to sign up for alphastar, no?

alphastar's website doesn't really provide much learning

I was looking at their classes and it costs $2,000 for most of their classes :skull AoPS is the best for classes and learning.
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MathDolphin95
2387 posts
MathDolphin95
#10 h  Apr 9, 2025, 5:05 PM • 2 Y
Y by BigOrca, MathNinja9
this one!

aops is great! alcumus is good and classes are fun (I love the self-paced ones except I ran out :()
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JerryZYang
79 posts
JerryZYang
#11 h  Apr 9, 2025, 5:08 PM • 2 Y
Y by BigOrca, MathDolphin95
Personally I like aops. But I do khan academy too. I actually also did think academy before but it wasn't too useful...
This post has been edited 1 time. Last edited by JerryZYang, Apr 9, 2025, 5:08 PM
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luciazhu1105
14 posts
luciazhu1105
#12 h  Apr 9, 2025, 10:20 PM • 2 Y
Y by MathDolphin95, MmathB
I like aops and beast academy along with. khan academy, but if ur doing less complex math, prodigy is really fun but I would do research and see what works for u
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acuL_51
8 posts
acuL_51
#13 h  Apr 9, 2025, 10:21 PM • 1 Y
Y by GallopingUnicorn45
you shouldnt be asking this on aops (;
This post has been edited 1 time. Last edited by acuL_51, Apr 9, 2025, 10:23 PM
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GYRAD0S
16 posts
GYRAD0S
#14 h  Apr 9, 2025, 11:04 PM
Y by
mathdash is also good for mock contests
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HoneyHap
4 posts
HoneyHap
#15 h  Apr 9, 2025, 11:19 PM
Y by
this website is really good for preparing for amc contests - https://math.llmlab.io/
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