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H
k a May Highlights and 2025 AoPS Online Class Information
jlacosta   0
May 1, 2025
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]
Our full course list for upcoming classes is below:
All classes run 7:30pm-8:45pm ET/4:30pm - 5:45pm PT unless otherwise noted.

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0 replies
jlacosta
May 1, 2025
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
J
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Introducing myself at AoPS, and what's your magic wand?
asuth_asuth   1200
N 9 minutes ago by StrahdVonZarovich
Hi!

I'm Andrew Sutherland. I'm the new Chief Product Officer at AoPS. As you may have read, Richard is retiring and Ben Kornell and I are working together to lead the company now. I'm leading all the software and digital stuff at AoPS. I just wanted to say hello and introduce myself! I'm really excited to be part of the special community that is AoPS.

Previously, I founded Quizlet as a 15-year-old high school student. I did Course 6 at MIT and then left to lead Quizlet full-time for a total of 14 years. I took a few years off and now I'm doing AoPS! I wrote more about all that on my blog: https://asuth.com/im-joining-aops

I have a question for all of you. If you could wave a magic wand, and change anything about AoPS, what would it be? All suggestions welcome! Thank you.
1200 replies
asuth_asuth
Mar 30, 2025
StrahdVonZarovich
9 minutes ago
J
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Geometry hard problem
noneofyou34   0
an hour ago
Let ABC be a triangle with incircle Γ. The tangency points of Γ with sides BC, CA, AB are A1, B1, C1 respectively. Line B1C1 intersects line BC at point A2. Similarly, points B2 and C2 are constructed. Prove that the perpendicular lines from A2, B2, C2 to lines AA1, BB1, CC1 respectively are concurret.
0 replies
noneofyou34
an hour ago
0 replies
J
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JBMO TST Bosnia and Herzegovina P4
Steve12345   3
N an hour ago by AylyGayypow009
$4.$ Let there be a variable positive integer whose last two digits are $3's$. Prove that this number is divisible by a prime greater than $7$.
3 replies
Steve12345
Jul 7, 2019
AylyGayypow009
an hour ago
J
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Numbers on a circle
navi_09220114   1
N an hour ago by gabriel_lee
Source: TASIMO 2025 Day 1 Problem 1
For a given positive integer $n$, determine the smallest integer $k$, such that it is possible to place numbers $1,2,3,\dots, 2n$ around a circle so that the sum of every $n$ consecutive numbers takes one of at most $k$ values.
1 reply
navi_09220114
5 hours ago
gabriel_lee
an hour ago
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prove triangles are similar
N.T.TUAN   58
N an hour ago by mathwiz_1207
Source: USA Team Selection Test 2007, Problem 5
Triangle $ ABC$ is inscribed in circle $ \omega$. The tangent lines to $ \omega$ at $ B$ and $ C$ meet at $ T$. Point $ S$ lies on ray $ BC$ such that $ AS \perp AT$. Points $ B_1$ and $ C_1$ lie on ray $ ST$ (with $ C_1$ in between $ B_1$ and $ S$) such that $ B_1T = BT = C_1T$. Prove that triangles $ ABC$ and $ AB_1C_1$ are similar to each other.
58 replies
N.T.TUAN
Dec 8, 2007
mathwiz_1207
an hour ago
J
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Prove n is square-free given divisibility condition
CatalanThinker   5
N an hour ago by nabodorbuco2
Source: 1995 Indian Mathematical Olympiad
Let \( n \) be a positive integer such that \( n \) divides the sum
\[ 1 + \sum_{i=1}^{n-1} i^{n-1}. \]Prove that \( n \) is square-free.
5 replies
CatalanThinker
Today at 3:05 AM
nabodorbuco2
an hour ago
J
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1998 KJMO P1 Finding integer solutions(easy)
RL_parkgong_0106   2
N an hour ago by JH_K2IMO
Source: 1998 KJMO P1
Show that there exist no integer solutions $(x, y, z)$ to the equation

$$x^3+2y^3+4z^3=9$$
2 replies
RL_parkgong_0106
Jun 30, 2024
JH_K2IMO
an hour ago
J
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Find all functions $f$: \(\mathbb{R}\) \(\rightarrow\) \(\mathbb{R}\) such : $f(
guramuta   3
N an hour ago by nabodorbuco2
Find all functions $f$: \(\mathbb{R}\) \(\rightarrow\) \(\mathbb{R}\) such :
$f(x+yf(x)) + f(xf(y)-y) = f(x) - f(y) + 2xy$
3 replies
guramuta
Yesterday at 2:18 PM
nabodorbuco2
an hour ago
J
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Hard Inequality
JARP091   3
N 2 hours ago by whwlqkd
Source: Own?
Let \( a, b, c > 0 \) with \( abc = 1 \). Prove that
\[ \frac{a^5}{b^2 + 2c^3} + \frac{2b^5}{3c + a^6} + \frac{c^7}{a + b^4} \geq 2. \]
3 replies
JARP091
Today at 4:55 AM
whwlqkd
2 hours ago
J
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Easy geometry problem
dwrty   1
N 2 hours ago by Ianis

Let ABCD be a square with center O. Triangles BJC and CKD are constructed outward from the square such that BJ = CJ = CK = DK. Let M be the midpoint of CJ. Prove that the lines OM and BK are perpendicular.

1 reply
dwrty
2 hours ago
Ianis
2 hours ago
J
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gcd of a^2+b^2-nab and a+b divides n+2 , when a,b are coprime positive
parmenides51   3
N 2 hours ago by FrancoGiosefAG
Source: Mexican Mathematical Olympiad 1988 OMM P5
If $a$ and $b$ are coprime positive integers and $n$ an integer, prove that the greatest common divisor of $a^2+b^2-nab$ and $a+b$ divides $n+2$.
3 replies
parmenides51
Jul 27, 2018
FrancoGiosefAG
2 hours ago
J
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New user not allowed to use LaTeX
Cats_on_a_computer   8
N Today at 6:04 AM by Cats_on_a_computer
Do I seriously have to post everyday for 14 days for me not to be considered a “new user? I didn’t even upload any images, I just used LaTeX. How am I supposed to write anything without LaTeX?
8 replies
Cats_on_a_computer
Yesterday at 11:43 AM
Cats_on_a_computer
Today at 6:04 AM
J
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Time travel
centslordm   19
N Today at 4:07 AM by Yihangzh
IMAGE
19 replies
centslordm
Yesterday at 10:59 PM
Yihangzh
Today at 4:07 AM
J
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Duplicate Gamebot
cz1917   3
N Today at 3:28 AM by aiops
The same problem of Alcumus is posted twice by Gamebot. They even have different links:
First Link
Second Link
3 replies
cz1917
Today at 1:36 AM
aiops
Today at 3:28 AM
J
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J
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k Question...
RedChameleon   2
N Apr 14, 2025 by jkim0656
Why aren't ss threads locking anymore? Usually they lock when they become resolved and more than half of the threads open already have a solution.
2 replies
RedChameleon
Apr 14, 2025
jkim0656
Apr 14, 2025
J
Question...
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Reveal topic tags
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RedChameleon
1243 posts
RedChameleon
#1 h  Apr 14, 2025, 8:18 PM
Y by
Why aren't ss threads locking anymore? Usually they lock when they become resolved and more than half of the threads open already have a solution.
Z Y
The post below has been deleted. Click to close.
This post has been deleted. Click here to see post.
Craftybutterfly
527 posts
Craftybutterfly
#2 h  Apr 14, 2025, 8:52 PM
Y by
Site admins need to lock them. Since they are busy all the time, it takes them a while to lock the threads.
Z Y
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jkim0656
1041 posts
jkim0656
#3 h  Apr 14, 2025, 9:36 PM
Y by
i think they lock the same...dunno
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