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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
J
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k i Suggestion Form
jwelsh   0
May 6, 2021
Hello!

Given the number of suggestions we’ve been receiving, we’re transitioning to a suggestion form. If you have a suggestion for the AoPS website, please submit the Google Form:
Suggestion Form

To keep all new suggestions together, any new suggestion threads posted will be deleted.

Please remember that if you find a bug outside of FTW! (after refreshing to make sure it’s not a glitch), make sure you’re following the How to write a bug report instructions and using the proper format to report the bug.

Please check the FTW! thread for bugs and post any new ones in the For the Win! and Other Games Support Forum.
0 replies
jwelsh
May 6, 2021
0 replies
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k i Read me first / How to write a bug report
slester   3
N May 4, 2019 by LauraZed
Greetings, AoPS users!

If you're reading this post, that means you've come across some kind of bug, error, or misbehavior, which nobody likes! To help us developers solve the problem as quickly as possible, we need enough information to understand what happened. Following these guidelines will help us squash those bugs more effectively.

Before submitting a bug report, please confirm the issue exists in other browsers or other computers if you have access to them.

For a list of many common questions and issues, please see our user created FAQ, Community FAQ, or For the Win! FAQ.

What is a bug?
A bug is a misbehavior that is reproducible. If a refresh makes it go away 100% of the time, then it isn't a bug, but rather a glitch. That's when your browser has some strange file cached, or for some reason doesn't render the page like it should. Please don't report glitches, since we generally cannot fix them. A glitch that happens more than a few times, though, could be an intermittent bug.

If something is wrong in the wiki, you can change it! The AoPS Wiki is user-editable, and it may be defaced from time to time. You can revert these changes yourself, but if you notice a particular user defacing the wiki, please let an admin know.

The subject
The subject line should explain as clearly as possible what went wrong.

Bad: Forum doesn't work
Good: Switching between threads quickly shows blank page.

The report
Use this format to report bugs. Be as specific as possible. If you don't know the answer exactly, give us as much information as you know. Attaching a screenshot is helpful if you can take one.

Summary of the problem:
Page URL:
Steps to reproduce:
1.
2.
3.
...
Expected behavior:
Frequency:
Operating system(s):
Browser(s), including version:
Additional information:

If your computer or tablet is school issued, please indicate this under Additional information.

Example
Summary of the problem: When I click back and forth between two threads in the site support section, the content of the threads no longer show up. (See attached screenshot.)
Page URL: http://artofproblemsolving.com/community/c10_site_support
Steps to reproduce:
1. Go to the Site Support forum.
2. Click on any thread.
3. Click quickly on a different thread.
Expected behavior: To see the second thread.
Frequency: Every time
Operating system: Mac OS X
Browser: Chrome and Firefox
Additional information: Only happens in the Site Support forum. My tablet is school issued, but I have the problem at both school and home.

How to take a screenshot
Mac OS X: If you type ⌘+Shift+4, you'll get a "crosshairs" that lets you take a custom screenshot size. Just click and drag to select the area you want to take a picture of. If you type ⌘+Shift+4+space, you can take a screenshot of a specific window. All screenshots will show up on your desktop.

Windows: Hit the Windows logo key+PrtScn, and a screenshot of your entire screen. Alternatively, you can hit Alt+PrtScn to take a screenshot of the currently selected window. All screenshots are saved to the Pictures → Screenshots folder.

Advanced
If you're a bit more comfortable with how browsers work, you can also show us what happens in the JavaScript console.

In Chrome, type CTRL+Shift+J (Windows, Linux) or ⌘+Option+J (Mac).
In Firefox, type CTRL+Shift+K (Windows, Linux) or ⌘+Option+K (Mac).
In Internet Explorer, it's the F12 key.
In Safari, first enable the Develop menu: Preferences → Advanced, click "Show Develop menu in menu bar." Then either go to Develop → Show Error console or type Option+⌘+C.

It'll look something like this:
IMAGE
3 replies
slester
Apr 9, 2015
LauraZed
May 4, 2019
J
H
k i Community Safety
dcouchman   0
Jan 18, 2018
If you find content on the AoPS Community that makes you concerned for a user's health or safety, please alert AoPS Administrators using the report button (Z) or by emailing sheriff@aops.com . You should provide a description of the content and a link in your message. If it's an emergency, call 911 or whatever the local emergency services are in your country.

Please also use those steps to alert us if bullying behavior is being directed at you or another user. Content that is "unlawful, harmful, threatening, abusive, harassing, tortuous, defamatory, vulgar, obscene, libelous, invasive of another's privacy, hateful, or racially, ethnically or otherwise objectionable" (AoPS Terms of Service 5.d) or that otherwise bullies people is not tolerated on AoPS, and accounts that post such content may be terminated or suspended.
0 replies
dcouchman
Jan 18, 2018
0 replies
J
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Inspired by xytunghoanh
sqing   1
N 10 minutes ago by lbh_qys
Source: Own
Let $ a,b,c\ge 0, a^2 +b^2 +c^2 =3. $ Prove that
$$ \sqrt 3 \leq a+b+c+ ab^2 + bc^2+ ca^2\leq 6$$Let $ a,b,c\ge 0, a+b+c+a^2 +b^2 +c^2 =6. $ Prove that
$$ ab+bc+ca+ ab^2 + bc^2+ ca^2 \leq 6$$
1 reply
sqing
an hour ago
lbh_qys
10 minutes ago
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egmo 2018 p4
microsoft_office_word   29
N 28 minutes ago by math-olympiad-clown
Source: EGMO 2018 P4
A domino is a $ 1 \times 2 $ or $ 2 \times 1 $ tile.
Let $n \ge 3 $ be an integer. Dominoes are placed on an $n \times n$ board in such a way that each domino covers exactly two cells of the board, and dominoes do not overlap. The value of a row or column is the number of dominoes that cover at least one cell of this row or column. The configuration is called balanced if there exists some $k \ge 1 $ such that each row and each column has a value of $k$. Prove that a balanced configuration exists for every $n \ge 3 $, and find the minimum number of dominoes needed in such a configuration.
29 replies
microsoft_office_word
Apr 12, 2018
math-olympiad-clown
28 minutes ago
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Tangents to a cyclic quadrilateral
v_Enhance   24
N 37 minutes ago by hectorleo123
Source: ELMO Shortlist 2013: Problem G9, by Allen Liu
Let $ABCD$ be a cyclic quadrilateral inscribed in circle $\omega$ whose diagonals meet at $F$. Lines $AB$ and $CD$ meet at $E$. Segment $EF$ intersects $\omega$ at $X$. Lines $BX$ and $CD$ meet at $M$, and lines $CX$ and $AB$ meet at $N$. Prove that $MN$ and $BC$ concur with the tangent to $\omega$ at $X$.

Proposed by Allen Liu
24 replies
v_Enhance
Jul 23, 2013
hectorleo123
37 minutes ago
J
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integer functional equation
ABCDE   152
N 38 minutes ago by pco
Source: 2015 IMO Shortlist A2
Determine all functions $f:\mathbb{Z}\rightarrow\mathbb{Z}$ with the property that \[f(x-f(y))=f(f(x))-f(y)-1\]holds for all $x,y\in\mathbb{Z}$.
152 replies
ABCDE
Jul 7, 2016
pco
38 minutes ago
J
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k Multiple black things [RESOLVED]
Yiyj   8
N May 12, 2025 by Yiyj
Why is there like multiple black thingies as shown in the attachments? When I also clicked on other threads, the black thingies for all of them stayed. So weird…
8 replies
Yiyj
May 12, 2025
Yiyj
May 12, 2025
J
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File uploads on aops
ohiorizzler1434   3
N May 12, 2025 by Craftybutterfly
What is the length of time a file uploaded to cdn.artofproblemsolving lasts before it is taken down?
3 replies
ohiorizzler1434
May 12, 2025
Craftybutterfly
May 12, 2025
J
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k Happy mother’s day
Rice_Farmer   4
N May 12, 2025 by JohannIsBach
Happy Mother’s Day!
4 replies
Rice_Farmer
May 11, 2025
JohannIsBach
May 12, 2025
J
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k happy mothers day!
JohannIsBach   5
N May 12, 2025 by JohannIsBach
hi! happy mothers day! hows it goin? happy mothers day!
5 replies
JohannIsBach
May 11, 2025
JohannIsBach
May 12, 2025
J
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k (Another) Reaper bug
RedChameleon   3
N May 8, 2025 by jlacosta
Sbarrack updated the home page of reaper. Now when I want to click on current or upcoming games, when I click the buttons, they do not redirect me to the game.

I have not recorded footage because I'm lazy but I'm currently on a Chromebook and I'm using Chrome.
3 replies
RedChameleon
May 8, 2025
jlacosta
May 8, 2025
J
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k Is it a error for reaper
tyrantfire4   5
N May 8, 2025 by k1glaucus
I was going to reap on reaper and it put me on a strange reaper page I figured out to to reap by using the url
https://artofproblemsolving.com/reaper/reaper?id=85and changing the 85 but it was so weird I kept the page
5 replies
tyrantfire4
May 8, 2025
k1glaucus
May 8, 2025
J
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Reaper bug
ChessPanther   3
N May 8, 2025 by Craftybutterfly
In reaper game 96 it says it begins in 3 days but when you look at the upcoming games it says it starts on June 10th? I don't know which it starts on.
3 replies
ChessPanther
May 8, 2025
Craftybutterfly
May 8, 2025
J
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k Latex problem
hakuj   2
N May 8, 2025 by k1glaucus
Why is Latex not allowed in the text?It is said that new user is not allowed to post an image.How could I post a math problem without Latex?
2 replies
hakuj
May 8, 2025
k1glaucus
May 8, 2025
J
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k Any way to collapse these huge headers?
ComicallyUnfunny   3
N May 8, 2025 by k1glaucus
As you can see, literally 60% of screen space is consumed by headers (even with the banner announcement closed). Is there any way to actually use more screen space for the content?
3 replies
ComicallyUnfunny
May 8, 2025
k1glaucus
May 8, 2025
J
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Python exit() module decriptions appear as "undefined"
SoaringHigh   16
N May 7, 2025 by LostInBali
Summary of the problem: When using exit() (or quit()) in the Python windows on AoPS the "Description" and "To fix" options show up as "undefined"
sample program
Page URL: N/A
Steps to reproduce:
1. Use the AoPS Python module to execute the exit() or quit() functions in a program. (try running the sample program)
Expected behavior: The "Description" and "To fix" sections give a description of SystemExit
Frequency: Always
Operating system(s): Windows 11 Home
Browser(s), including version: Microsoft Edge 130.0.2849.46
Additional information: N/A
16 replies
SoaringHigh
Oct 22, 2024
LostInBali
May 7, 2025
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weird Condition
B1t   8
N Apr 30, 2025 by lolsamo
Source: Mongolian TST 2025 P4
deleted for a while
8 replies
B1t
Apr 27, 2025
lolsamo
Apr 30, 2025
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weird Condition
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Reveal topic tags
geometry
L
G H BBookmark kLocked kLocked NReply
Source: Mongolian TST 2025 P4
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B1t
24 posts
B1t
#1 h  Apr 27, 2025, 1:37 PM
Y by
deleted for a while
This post has been edited 5 times. Last edited by B1t, Apr 30, 2025, 6:56 AM
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B1t
24 posts
B1t
#2 h  Apr 27, 2025, 4:31 PM
Y by
no one ?
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Ilikeminecraft
650 posts
Ilikeminecraft
#3 h  Apr 27, 2025, 4:45 PM
Y by
feet from what to what
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B1t
24 posts
B1t
#5 h  Apr 27, 2025, 5:25 PM
Y by
Ilikeminecraft wrote:
feet from what to what

Sorry, are you having trouble understanding this?
This post has been edited 1 time. Last edited by B1t, Apr 27, 2025, 5:33 PM
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MathLuis
1530 posts
MathLuis
#6 h  Apr 27, 2025, 11:35 PM
Y by
Let $N$ midpoint of arc $EAF$ on $(AEF)$ then let $EF \cap BC=H$ notice that $HA \cdot HN=HE \cdot HF=HD \cdot HG$ so $NAGD$ is cyclic and thus by the perpendiculars we get $N,I,G$ colinear, now let $D'$ the A-excenter of $\triangle DEF$, let $K,L$ the E,F excenters of $\triangle AEF$ respectively then finally let $G'$ the D'-queue point of $\triangle D'KL$, notice how we have $D'G' \parallel BC$ from the condition but also from radax $D',G,'H$ colinear which forces that $D=D'$ and $G=G'$ and thus we are done by I-E Lemma.
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Sadigly
223 posts
Sadigly
#7 h  Apr 29, 2025, 10:35 PM
Y by
Probably from IMO SL, since this problem is also on Azerbaijan IMO TST, so please remove this post
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Assassino9931
1353 posts
Assassino9931
#8 h  Apr 29, 2025, 11:59 PM
Y by
Sadigly wrote:
Probably from IMO SL, since this problem is also on Azerbaijan IMO TST, so please remove this post

No, it's not from IMO SL, but it's very curious where is it from then, given the coincidence.
Z K Y
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B1t
24 posts
B1t
#9 h  Apr 30, 2025, 6:53 AM
Y by
Assassino9931 wrote:
Sadigly wrote:
Probably from IMO SL, since this problem is also on Azerbaijan IMO TST, so please remove this post

No, it's not from IMO SL, but it's very curious where is it from then, given the coincidence.

What should we do with this problem — should we keep it or remove it? Problem 6 was similarly a duplicate and was removed before anyone wrote a solution. This one, however, has already been discussed, but I can still remove the statement if necessary — should I?
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lolsamo
12 posts
lolsamo
#10 h  Apr 30, 2025, 10:37 AM
Y by
The problem is from another international shortlist, not an olympiad though.
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