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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
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
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
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
Simple Geometry
AbdulWaheed   1
N 3 minutes ago by Adywastaken
Source: EGMO
Try to avoid Directed angles
Let ABC be an acute triangle inscribed in circle $\Omega$. Let $X$ be the midpoint of the arc $\overarc{BC}$ not containing $A$ and define $Y, Z$ similarly. Show that the orthocenter of $XYZ$ is the incenter $I$ of $ABC$.
1 reply
AbdulWaheed
Today at 5:15 AM
Adywastaken
3 minutes ago
inequality thing
BinariouslyRandom   2
N 30 minutes ago by BinariouslyRandom
Source: Philippine MO 2025 P5
Find the largest real constant $k$ for which the inequality \[ (a^2+3)(b^2+3)(c^2+3)(d^2+3) + k(a-1)(b-1)(c-1)(d-1) \ge 0 \]holds for all real numbers $a$, $b$, $c$, and $d$.

answer
2 replies
BinariouslyRandom
2 hours ago
BinariouslyRandom
30 minutes ago
Geometry Concurrence
KHOMNYO2   0
an hour ago
Given triangle $XYZ$ such that $XY \neq XZ$. Let excircle-$X$ be tangent with $YZ, ZX, XY$ at points $U, V, W$ respectively. Let $R$ and $S$ be points on the segment $XZ, XY$ respectively such that $RS$ is parallel to $YZ$. Lastly, let $\gamma$ be the circle that is externally tangent with the excircle-$X$ on point $T$. Prove that $VW, UT$, and $RS$ concur at a point.
0 replies
KHOMNYO2
an hour ago
0 replies
inequality
mathematical-forest   1
N an hour ago by lbh_qys
Positive real numbers $x_{1} ,x_{2} \cdots ,x_{n}$,satisfied $\sum_{i=1}^{n}x_{i} =1$
Proof:$$\sum_{i=1}^{n} \frac{\min  \left \{  x_{i-1},x_{i}\right \}\max \left \{  x_{i},x_{i+1}\right \}  }{x_{i}} \le 1$$
1 reply
mathematical-forest
an hour ago
lbh_qys
an hour ago
All Topics Marked
alpha31415   14
N Yesterday at 10:24 AM by alpha31415
Excuse me!
for I am a frashman in aops.I wonder how I could get back to mark all my read.All topics in the forum became as if they had been marked.Would someone please help me deal with it???
14 replies
alpha31415
May 16, 2025
alpha31415
Yesterday at 10:24 AM
Help Needed to Configure the Settings
Saucepan_man02   3
N Yesterday at 2:31 AM by bpan2021
Hello..

Can anyone tell me, is it possible to make something like: configure my AoPS account's settings such that guest users (or non-friend users) can't look/track down my posts/activity ?
If it is possible, anyone kindly help me.
Thanks...
3 replies
Saucepan_man02
Yesterday at 12:11 AM
bpan2021
Yesterday at 2:31 AM
k Writing Problem is Grey
Anzzz   2
N Wednesday at 8:32 PM by jlacosta
In the writing problem in a Self - Paced class, I submitted it, and got graded. However, the writing problem icon remains grey, like it wasn't graded yet. I tried refreshing it multiple times, but it doesn't change. This doesn't really change anything, but I keep feeling like I haven't done it when I review my progress.

PS: This has not happened before.
2 replies
Anzzz
May 18, 2025
jlacosta
Wednesday at 8:32 PM
k alcumus going crazy?
LittleSnake____   61
N May 19, 2025 by jlacosta
all of a sudden, the alcumus forum has gotten completely exploded by gamebot's posts.

https://artofproblemsolving.com/community/c63h3570498_alcumus_going_crazy
61 replies
LittleSnake____
May 18, 2025
jlacosta
May 19, 2025
k New user not allowed to use LaTeX
Cats_on_a_computer   8
N May 19, 2025 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
May 18, 2025
Cats_on_a_computer
May 19, 2025
k Duplicate Gamebot
cz1917   3
N May 19, 2025 by aiops
The same problem of Alcumus is posted twice by Gamebot. They even have different links:
First Link
Second Link
3 replies
cz1917
May 19, 2025
aiops
May 19, 2025
k Time travel
centslordm   11
N May 19, 2025 by stjwyl
IMAGE
11 replies
centslordm
May 18, 2025
stjwyl
May 19, 2025
k ALCUMUS IS BROKEN AGAIN!!!!
Neilmarar2022   1
N May 18, 2025 by Neilmarar2022
Game Bot is going crazy again... there is an insane number of posts in the last minute
1 reply
Neilmarar2022
May 18, 2025
Neilmarar2022
May 18, 2025
k Gamebot Problem
zhenghua   4
N May 18, 2025 by MathPerson12321
Summary of the problem: Multiple topics of the same problem are on the feed.
Page URL: Global Feed
Steps to reproduce:
1. Open the global feed
2. There are a lot of topics of the same problem.
Expected behavior: Should only be one topic.
Frequency: 100%
Operating system(s): Windows 10
Browser(s), including version: Google (don't know which version)
Additional information: None
4 replies
zhenghua
May 18, 2025
MathPerson12321
May 18, 2025
k My problem with AoPS account
BBNoDollar   2
N May 18, 2025 by SpeedCuber7
Hello ! Sorry because this is not a math problem. I wanted to post an image with a math problem, but it says I can t add photos because my account is too new. I joined in 2 May 2025, so my account is more than 2 weeks old. How do I find a solution? Thanks!
2 replies
BBNoDollar
May 18, 2025
SpeedCuber7
May 18, 2025
Nagel point, two lines intersecting on circumcircle
goodar2006   2
N Sep 22, 2012 by ACCCGS8
Source: Iran 3rd round 2012-Geometry exam-P2
Let the Nagel point of triangle $ABC$ be $N$. We draw lines from $B$ and $C$ to $N$ so that these lines intersect sides $AC$ and $AB$ in $D$ and $E$ respectively. $M$ and $T$ are midpoints of segments $BE$ and $CD$ respectively. $P$ is the second intersection point of circumcircles of triangles $BEN$ and $CDN$. $l_1$ and $l_2$ are perpendicular lines to $PM$ and $PT$ in points $M$ and $T$ respectively. Prove that lines $l_1$ and $l_2$ intersect on the circumcircle of triangle $ABC$.

Proposed by Nima Hamidi
2 replies
goodar2006
Sep 20, 2012
ACCCGS8
Sep 22, 2012
Nagel point, two lines intersecting on circumcircle
G H J
Source: Iran 3rd round 2012-Geometry exam-P2
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goodar2006
1347 posts
#1 • 2 Y
Y by Adventure10, Mango247
Let the Nagel point of triangle $ABC$ be $N$. We draw lines from $B$ and $C$ to $N$ so that these lines intersect sides $AC$ and $AB$ in $D$ and $E$ respectively. $M$ and $T$ are midpoints of segments $BE$ and $CD$ respectively. $P$ is the second intersection point of circumcircles of triangles $BEN$ and $CDN$. $l_1$ and $l_2$ are perpendicular lines to $PM$ and $PT$ in points $M$ and $T$ respectively. Prove that lines $l_1$ and $l_2$ intersect on the circumcircle of triangle $ABC$.

Proposed by Nima Hamidi
This post has been edited 1 time. Last edited by goodar2006, Sep 28, 2012, 1:25 PM
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tobash_co
87 posts
#2 • 3 Y
Y by Adventure10, Mango247, and 1 other user
If incircle touches $AB,AC$ at $X,Y$ then $BE=AX=AY=CD$. Since $P$ is the center of spiral similarity sending $BE$ to $DC$, we immediately get $\bigtriangleup PEB\equiv \bigtriangleup PCD$. So $\angle EMP=\angle CTP$, so $A,M,P,T$ are concyclic together with $G$.

Thus if $\l_1,\l_2$ intersect at $G$ then $GM=GT$, $BM=CT$ and $\angle GMB=\angle GTC$. Thus $\bigtriangleup GMB\equiv \bigtriangleup GTC$, and so \[\angle ABG=\angle AMG+\angle BGM=\angle ATG+\angle CGT=\angle ACG\], so $A,B,C,G$ are indeed concyclic.
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ACCCGS8
326 posts
#3 • 2 Y
Y by Adventure10, Mango247
Observe that $M$ is the Miquel point of complete quadrilateral consisting of points $A, E, B, C, D, N$ so $ABPD$ and $AEPC$ are cyclic. Thus $\angle BEP = \angle DCP$ and $\angle EBP = \angle CDP$. Also $BE=AF=AG=DC$ so $\triangle BEP$ is congruent to $\triangle DCP$. Now $PM, PT$ are corresponding medians, so $\angle PME =\angle PTC$ so $AMPT$ is cyclic. Thus $AMPTX$ is cyclic so $\angle MXT = \angle BAC$. By RHS, $\triangle XMP$ is congruent to $\triangle XTP$ so $XM=XT$. Also, $MB=TC$ and since $AMTX$ is cyclic, $\angle XMB= \angle XTC$ so by SAS $\triangle XMB$ is congruent to $\triangle XTC$. Thus $\angle MXB=\angle TXC$ so $\angle BXC=\angle MXT=\angle BAC$ so $l_1, l_2$ intersect on the circumcircle of $\triangle ABC$.
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