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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
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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
J
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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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Complex number
ronitdeb   1
N an hour ago by alexheinis
Let $z_1, ... ,z_5$ be vertices of regular pentagon inscribed in a circle whose radius is $2$ and center is at $6+i8$. Find all possible values of $z_1^2+z_2^2+...+z_5^2$
1 reply
ronitdeb
Yesterday at 6:13 PM
alexheinis
an hour ago
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2-var inequality
sqing   9
N an hour ago by SunnyEvan
Source: Own
Let $ a,b>0 , a^2+b^2-ab\leq 1 . $ Prove that
$$a^3+b^3 -\frac{a^4}{b+1} -\frac{b^4}{a+1} \leq 1 $$
9 replies
1 viewing
sqing
May 27, 2025
SunnyEvan
an hour ago
J
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Set of Integers
billzhao   41
N an hour ago by endless_abyss
Source: USAMO 2004, problem 2
Suppose $a_1, \dots, a_n$ are integers whose greatest common divisor is 1. Let $S$ be a set of integers with the following properties:

(a) For $i=1, \dots, n$, $a_i \in S$.
(b) For $i,j = 1, \dots, n$ (not necessarily distinct), $a_i - a_j \in S$.
(c) For any integers $x,y \in S$, if $x+y \in S$, then $x-y \in S$.

Prove that $S$ must be equal to the set of all integers.
41 replies
billzhao
Apr 29, 2004
endless_abyss
an hour ago
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ai+aj is the multiple of n
Jackson0423   1
N an hour ago by alexheinis

Consider an increasing sequence of integers \( a_n \).
For every positive integer \( n \), there exist indices \( 1 \leq i < j \leq n \) such that \( a_i + a_j \) is divisible by \( n \).
Given that \( a_1 \geq 1 \), find the minimum possible value of \( a_{100} \).
1 reply
Jackson0423
Today at 12:41 AM
alexheinis
an hour ago
J
H
k AoPS Report Bar
Svnshiin3-QTPI   5
N Wednesday at 8:18 PM by jlacosta
Hello there!
This is my first AoPS class, and I was wondering why my report bar is orange.
I have completed all of the Challenge homework problems, as well as the writing problems.
Is this because the writing problems have not been graded yet?
If not, are there any other assignments I need to complete?
Thanks.

(edit: resolved)
5 replies
Svnshiin3-QTPI
May 28, 2025
jlacosta
Wednesday at 8:18 PM
J
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Stamina XP decreasing?
Craftybutterfly   29
N May 28, 2025 by Craftybutterfly
Summary of the problem: Last night when I checked, alcumus said I had 4250 stamina XP which is more than other people. However, when I just checked, it said I only earned 3905 XP. What is wrong?
Page URL: Hall of Fame
Steps to reproduce:
1. Go to hall of fame
2. Scroll to stamina XP earned
Expected behavior: It should still say I earned 4250 XP
Frequency: 100%
Operating system(s): HP Elitebook
Browser(s), including version: Chrome
IMAGE
29 replies
Craftybutterfly
May 22, 2025
Craftybutterfly
May 28, 2025
J
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Hide tag workaround
char0221   6
N May 27, 2025 by jlacosta
Summary of the problem: When quoting a tip tag, hovering over it causes a glitch where the tip tag's inner contents are "stuck" below the quotes.
Page URL: Any community message boards.
Steps to reproduce:
1. Create a message.
2. Insert a quote.
3. Inside the quote, put a tip tag.
4. Submit/preview, then hover over the tip tag.
Expected behavior: Tip tag does not stay when mouse is removed.
Frequency: 100%
Operating system(s): macOS Sequoia
Browser(s), including version: Safari 18.4
Additional information:
IMAGE
Also, make sure that the quote+tip is last.
[quote=char0221]
Try to close me!
[/quote]
6 replies
char0221
May 26, 2025
jlacosta
May 27, 2025
J
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k Who was the FIRST AoPS user (its not cisco man)
EaZ_Shadow   8
N May 27, 2025 by Craftybutterfly
Alright, if you look at any other user's page, you'll see a number attached to artofproblemsolving.com/community/users/(number). That number signifies the place in when that person entered. Alright. If i got the number 1163, I was the 1163rd person to join. But then who was the first one? With the number 1?
8 replies
EaZ_Shadow
May 25, 2025
Craftybutterfly
May 27, 2025
J
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k Request for the access of private marathons
Vulch   4
N May 26, 2025 by bpan2021
To all AoPS users and admin,
Sometimes I came across the marathon(i .e number theory marathon, functional equation marathon etc) which allow access only after submitting log in request.There is no other way to access the question related to that marathons.It would be glad to open all private marathons publicly.Thank you!
4 replies
Vulch
May 25, 2025
bpan2021
May 26, 2025
J
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k Mathcounts trainer slow?
HM2018   0
May 26, 2025
Summary of problem: The Mathcounts Trainer is slow again.
URL Page: https://artofproblemsolving.com/mathcounts_trainer/play
If you answer a question, it takes so long for it to show you the answer.
Behavior (expected): Should show the answer pretty quickly (wasn't Mathcounts Trainer updated recently?)
0 replies
HM2018
May 26, 2025
0 replies
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Character encoding?
char0221   0
May 26, 2025
Summary of the problem: When using the "js", "java", "c", and "cpp" code tags, a left square bracket (i.e. "[") does not show. Instead, "[" appears.
Page URL: Any AoPS message board or community area.
Steps to reproduce:
1. Create a new message.
2. Inside, use a coding language template. I have not tried the following: Ruby, Go, C# (is there even on for C#?), and Python
3. Type "[".
4. Watch in amazement as your code is ruined.
Expected behavior: Inside the template, should make "[" appear.
Frequency: 100%
Operating system(s): macOS Sequoia
Browser(s), including version: Safari 18.4
Additional information: See below.
-|-leftbracket-|-]

It is "[" next to "]". Only the left bracket does not render.
0 replies
char0221
May 26, 2025
0 replies
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k Who is Halp! ? (resolvedd)
A7456321   8
N May 25, 2025 by JohannIsBach
Is Halp! a bot? This user has been posting questions in nearly all of my AoPS classes when the user isn't a part of the class, and this user has 150k posts.
8 replies
A7456321
May 24, 2025
JohannIsBach
May 25, 2025
J
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k How to create a poll?
whwlqkd   32
N May 25, 2025 by Yiyj
How to create a poll in aops?
32 replies
whwlqkd
May 24, 2025
Yiyj
May 25, 2025
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k banned myself from own blog
Spacepandamath13   8
N May 25, 2025 by sultanine
I got curious and decided to see if I can ban myself from my own blog.
can site admins give it back? it says site admins are the administrators of this blog

I honestly don't know where I come up with stuff like this
8 replies
Spacepandamath13
May 24, 2025
sultanine
May 25, 2025
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Easy perpendicularity
a_507_bc   1
N Apr 15, 2025 by zaidova
Source: Caucasus MO 2024, Juniors P2
The rhombuses $ABDK$ and $CBEL$ are arranged so that $B$ lies on the segment $AC$ and $E$ lies on the segment $BD$. Point $M$ is the midpoint of $KL$. Prove that $\angle DME=90^{\circ}$.
1 reply
a_507_bc
Mar 15, 2024
zaidova
Apr 15, 2025
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Easy perpendicularity
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Reveal topic tags
geometry
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Source: Caucasus MO 2024, Juniors P2
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a_507_bc
678 posts
a_507_bc
#1 h  Mar 15, 2024, 12:21 PM
Y by
The rhombuses $ABDK$ and $CBEL$ are arranged so that $B$ lies on the segment $AC$ and $E$ lies on the segment $BD$. Point $M$ is the midpoint of $KL$. Prove that $\angle DME=90^{\circ}$.
This post has been edited 1 time. Last edited by a_507_bc, Mar 15, 2024, 12:21 PM
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zaidova
89 posts
zaidova
#2 h  Apr 15, 2025, 1:31 PM
Y by
Nice problem, can be solved with an easy construction. Just construct a parallelogram with diagonal $KL$. Let the vertex on $AK$ be $P$, and Let the vertex $KD \cap LC=Q$. $PLKQ$ is a parallelogram. Let side of the $BCLE$ rhombus be $x$ and let $PK=y=ED=LQ$. Then we get $AB=AK=BD=KD=PE=x+y$ Now draw a line passing through point $M$, parallel to $PL$. Say that $X$, (parallel line passing through $M$) intersects $ED$. Then it is easy to see $EX=XD$. ===> $XE=XD=PK/2=y/2$ We have to show it is also equal to $MX$. Let the line passing through $M$ also intersect $AK$ at $Y$. Then $MY=PL/2=(PE+EL)/2=(AB+BC)/2=((x+y)+x)/2=x+y/2$. $PE=AB=x+y=XY$==>$MX=XY-MY=x+y-x-y/2=y/2$.
So, we get $MX=XE=XD$, $ \angle DME=90$. Done!
This post has been edited 3 times. Last edited by zaidova, Apr 15, 2025, 1:33 PM
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