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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
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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
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can you solve this..?
Jackson0423   0
a few seconds ago
Source: Own

Find the number of integer pairs \( (x, y) \) satisfying the equation
\[ 4x^2 - 3y^2 = 1 \]such that \( |x| \leq 2025 \).
0 replies
Jackson0423
a few seconds ago
0 replies
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JBMO Shortlist 2019 N7
Steve12345   6
N a minute ago by MR.1
Find all perfect squares $n$ such that if the positive integer $a\ge 15$ is some divisor $n$ then $a+15$ is a prime power.

Proposed by Saudi Arabia
6 replies
Steve12345
Sep 12, 2020
MR.1
a minute ago
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Either you get a 9th degree polynomial, or just easily find using inequality
Sadigly   1
N 2 minutes ago by Sadigly
Source: Azerbaijan Senior MO 2025 P2
Find all the positive reals $x,y,z$ satisfying the following equations: $$y=\frac6{(2x-1)^2}$$$$z=\frac6{(2y-1)^2}$$$$x=\frac6{(2z-1)^2}$$
1 reply
+1 w
Sadigly
11 minutes ago
Sadigly
2 minutes ago
J
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Gives typical russian combinatorics vibes
Sadigly   0
3 minutes ago
Source: Azerbaijan Senior MO 2025 P3
You are given a positive integer $n$. $n^2$ amount of people stand on coordinates $(x;y)$ where $x,y\in\{0;1;2;...;n-1\}$. Every person got a water cup and two people are considered to be neighbour if the distance between them is $1$. At the first minute, the person standing on coordinates $\{0;0\}$ got $1$ litres of water, and the other $n^2-1$ people's water cup is empty. Every minute, two neighbouring people are chosen that does not have the same amount of water in their water cups, and they equalize the amount of water in their water cups.

Prove that, no matter what, the person standing on the coordinates $\{x;y\}$ will not have more than $\frac1{x+y+1}$ litres of water.
0 replies
Sadigly
3 minutes ago
0 replies
J
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Python exit() module decriptions appear as "undefined"
SoaringHigh   16
N Yesterday at 6:03 PM 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
Yesterday at 6:03 PM
J
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k Reply box disappearing
Craftybutterfly   31
N Tuesday at 4:32 PM by jlacosta
For some reason, on my iPhone XR, when I press on the view my posts button, then press on an unlocked topic and scroll down or press go down button, the reply box disappears. I can’t use the proper format right now as I am on phone.
Summary of the problem: the lines above
setps to reproduce:
1. Go to your profile
2. Press on your posts button
3. press an unlocked topic and scroll down
Frequency: 100%
Browser: Chrome latest version
Device: iPhone XR
31 replies
Craftybutterfly
Apr 30, 2025
jlacosta
Tuesday at 4:32 PM
J
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k Alcumus Rating
awesometriangles   5
N Tuesday at 4:26 PM by jlacosta
My Alcumus rating for CP used to be something like a 90, then I went to do some homework for a class, and when I came back to alcumus, it is now a 40. I don't know what happened and I haven't touched C&P in the last hour or two, and I haven't gotten any wrong in it or anything to majorly decrease my rating. I also checked the topics, and each was either green or blue, like how I left it. Is this just me?

EDIT: My level is still the same too..., and idk if i should add an image, and if i should, what should I screenshot?
5 replies
awesometriangles
May 5, 2025
jlacosta
Tuesday at 4:26 PM
J
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k How to post a diagram
MTA_2024   1
N May 6, 2025 by k1glaucus
I can't find it, how can you submit a diagram with a geometry problem? Or any picture in general?
1 reply
MTA_2024
May 6, 2025
k1glaucus
May 6, 2025
J
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Error in forum
Speedysolver1   3
N May 5, 2025 by Craftybutterfly
Will put video
3 replies
Speedysolver1
Apr 23, 2025
Craftybutterfly
May 5, 2025
J
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k May the 4th (Late lol)
AbhayAttarde01   4
N May 5, 2025 by PikaPika999
nobody said this yet in site support????
Happy May 4th!
may the 4th be with you
and me my ap exams are tomorrow please be real
4 replies
AbhayAttarde01
May 4, 2025
PikaPika999
May 5, 2025
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k question
JohannIsBach   2
N May 4, 2025 by bpan2021
i have a question. where can u find what are hte most active forums?
2 replies
JohannIsBach
May 4, 2025
bpan2021
May 4, 2025
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k *RESOLVED* This has been going on for a while now, can anyone else relate?
jmr2010   3
N May 3, 2025 by jmr2010
Most of the time when I type in something for the tags or search for a user, the AoPS suggestion box pops up, and most of the time, when I click the suggestion, the box just disappears, meaning the automatic system usually never works
3 replies
jmr2010
Apr 29, 2025
jmr2010
May 3, 2025
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Cannot post PHP
char0221   4
N May 2, 2025 by k1glaucus
Summary of the problem: If I try to post anything with PHP (a coding language), it
Page URL: In any forum or private messages
Steps to reproduce:
1. Create a post.
2. Put some PHP inside, can't give example
Expected behavior: Should post the message
Frequency: 100%
Operating system(s): macOS Sequoia 15.2.1
Browser(s), including version: Safari
Additional information: See attachments
4 replies
char0221
Apr 30, 2025
k1glaucus
May 2, 2025
J
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k Side Panel UI Glitch
MathPerson12321   3
N May 1, 2025 by Demetri
Ill add more detail soon but on the side panel with the global feed, my feeds, private messages, and bookmarked threads/forums, the 2nd and 4th one I just mentioned are glitched. The 2nd one has the settings icon and then a music icon, and the 4th has an aops mini cube, the share button, and another that I don't know what it is.
Private messages are also being weird as the right panel with the edit button for example is offset.
3 replies
MathPerson12321
May 1, 2025
Demetri
May 1, 2025
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Euler line of incircle touching points /Reposted/
Eagle116   5
N Apr 20, 2025 by Tsikaloudakis
Let $ABC$ be a triangle with incentre $I$ and circumcentre $O$. Let $D,E,F$ be the touchpoints of the incircle with $BC$, $CA$, $AB$ respectively. Prove that $OI$ is the Euler line of $\vartriangle DEF$.
5 replies
Eagle116
Apr 19, 2025
Tsikaloudakis
Apr 20, 2025
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Euler line of incircle touching points /Reposted/
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Reveal topic tags
geometry
Euler Line
incenter
Euler
Inversion
homothety
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Eagle116
26 posts
Eagle116
#1 h  Apr 19, 2025, 2:48 PM
Y by
Let $ABC$ be a triangle with incentre $I$ and circumcentre $O$. Let $D,E,F$ be the touchpoints of the incircle with $BC$, $CA$, $AB$ respectively. Prove that $OI$ is the Euler line of $\vartriangle DEF$.
Z K Y
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Eagle116
26 posts
Eagle116
#2 h  Apr 19, 2025, 2:57 PM
Y by
Bumping?
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Double07
82 posts
Double07
#3 h  Apr 19, 2025, 3:49 PM
Y by
I'm pretty sure this is a well-known result, but it can quickly be proven with complex bash:

Consider $(DEF)$ the unit circle. Then $o=\frac{2def(d+e+f)}{(d+e)(e+f)(f+d)}$.

Consider $H$ the orthocenter of $\Delta DEF$, so $h=d+e+f$.

So we want to prove that $I, O, H$ are collinear $\iff \frac{o}{\overline{o}}=\frac{h}{\overline{h}}$

$\frac{h}{\overline{h}}=\frac{def(d+e+f)}{de+ef+fd}$.

$\frac{o}{\overline{o}}=\dfrac{\frac{2def(d+e+f)}{(d+e)(e+f)(f+d)}}{\frac{2(de+ef+fd)}{(d+e)(e+f)(f+d)}}=\frac{def(d+e+f)}{de+ef+fd}=\frac{h}{\overline{h}}$, and we're done.
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Eagle116
26 posts
Eagle116
#4 h  Apr 19, 2025, 3:52 PM
Y by
Synthetic please?
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Captainscrubz
65 posts
Captainscrubz
#5 h  Apr 19, 2025, 5:03 PM
Y by
Take inversion with respect to the incenter with radius as inradius
Let $A',B'$ and $C' $ be the midpoint of $EF,FD$ and $DE$
$\implies $ the vertices of $\triangle ABC$ go to the respective midpoints
Let $N_1$ be the center of $(A'B'C')$ then $\implies N'-I-O$
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Tsikaloudakis
981 posts
Tsikaloudakis
#6 h  Apr 20, 2025, 7:22 AM
Y by
apothikefsi
Z K Y
N Quick Reply
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