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H
k a My Retirement & New Leadership at AoPS
rrusczyk   1571
N Mar 26, 2025 by SmartGroot
I write today to announce my retirement as CEO from Art of Problem Solving. When I founded AoPS 22 years ago, I never imagined that we would reach so many students and families, or that we would find so many channels through which we discover, inspire, and train the great problem solvers of the next generation. I am very proud of all we have accomplished and I’m thankful for the many supporters who provided inspiration and encouragement along the way. I'm particularly grateful to all of the wonderful members of the AoPS Community!

I’m delighted to introduce our new leaders - Ben Kornell and Andrew Sutherland. Ben has extensive experience in education and edtech prior to joining AoPS as my successor as CEO, including starting like I did as a classroom teacher. He has a deep understanding of the value of our work because he’s an AoPS parent! Meanwhile, Andrew and I have common roots as founders of education companies; he launched Quizlet at age 15! His journey from founder to MIT to technology and product leader as our Chief Product Officer traces a pathway many of our students will follow in the years to come.

Thank you again for your support for Art of Problem Solving and we look forward to working with millions more wonderful problem solvers in the years to come.

And special thanks to all of the amazing AoPS team members who have helped build AoPS. We’ve come a long way from here:IMAGE
1571 replies
rrusczyk
Mar 24, 2025
SmartGroot
Mar 26, 2025
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H
k a March Highlights and 2025 AoPS Online Class Information
jlacosta   0
Mar 2, 2025
March is the month for State MATHCOUNTS competitions! Kudos to everyone who participated in their local chapter competitions and best of luck to all going to State! Join us on March 11th for a Math Jam devoted to our favorite Chapter competition problems! Are you interested in training for MATHCOUNTS? Be sure to check out our AMC 8/MATHCOUNTS Basics and Advanced courses.

Are you ready to level up with Olympiad training? Registration is open with early bird pricing available for our WOOT programs: MathWOOT (Levels 1 and 2), CodeWOOT, PhysicsWOOT, and ChemWOOT. What is WOOT? WOOT stands for Worldwide Online Olympiad Training and is a 7-month high school math Olympiad preparation and testing program that brings together many of the best students from around the world to learn Olympiad problem solving skills. Classes begin in September!

Do you have plans this summer? There are so many options to fit your schedule and goals whether attending a summer camp or taking online classes, it can be a great break from the routine of the school year. Check out our summer courses at AoPS Online, or if you want a math or language arts class that doesn’t have homework, but is an enriching summer experience, our AoPS Virtual Campus summer camps may be just the ticket! We are expanding our locations for our AoPS Academies across the country with 15 locations so far and new campuses opening in Saratoga CA, Johns Creek GA, and the Upper West Side NY. Check out this page for summer camp information.

Be sure to mark your calendars for the following events:
[list][*]March 5th (Wednesday), 4:30pm PT/7:30pm ET, HCSSiM Math Jam 2025. Amber Verser, Assistant Director of the Hampshire College Summer Studies in Mathematics, will host an information session about HCSSiM, a summer program for high school students.
[*]March 6th (Thursday), 4:00pm PT/7:00pm ET, Free Webinar on Math Competitions from elementary through high school. Join us for an enlightening session that demystifies the world of math competitions and helps you make informed decisions about your contest journey.
[*]March 11th (Tuesday), 4:30pm PT/7:30pm ET, 2025 MATHCOUNTS Chapter Discussion MATH JAM. AoPS instructors will discuss some of their favorite problems from the MATHCOUNTS Chapter Competition. All are welcome!
[*]March 13th (Thursday), 4:00pm PT/7:00pm ET, Free Webinar about Summer Camps at the Virtual Campus. Transform your summer into an unforgettable learning adventure! From elementary through high school, we offer dynamic summer camps featuring topics in mathematics, language arts, and competition preparation - all designed to fit your schedule and ignite your passion for learning.[/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.

Introductory: Grades 5-10

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Prealgebra 2
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Introduction to Algebra A Self-Paced

Introduction to Algebra A
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Introduction to Counting & Probability Self-Paced

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Intermediate Algebra
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Olympiad Geometry
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Calculus
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Group Theory
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Contest Preparation: Grades 6-12

MATHCOUNTS/AMC 8 Basics
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F=ma Problem Series
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Visit the pages linked for full schedule details for each of these programs!

MathWOOT Level 1
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Introduction to Programming with Python
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Mon, Tue, Wed & Thurs, Jun 23 - Jun 26 (meets every day of the week!)
0 replies
jlacosta
Mar 2, 2025
0 replies
J
H
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
H
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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Rows in a table without perfect squares
Assassino9931   0
3 minutes ago
Source: Bulgaria Spring Mathematical Competition 10.3
In the cell $(i,j)$ of a table $n\times n$ is written the number $(i-1)n + j$. Determine all positive integers $n$ such that there are exactly $2025$ rows not containing a perfect square.
0 replies
Assassino9931
3 minutes ago
0 replies
J
H
Fixed point config on external similar isosceles triangles
Assassino9931   0
4 minutes ago
Source: Bulgaria Spring Mathematical Competition 10.2
Let $AB$ be an acute scalene triangle. A point \( D \) varies on its side \( BC \). The points \( P \) and \( Q \) are the midpoints of the arcs \( \widehat{AB} \) and \( \widehat{AC} \) (not containing \( D \)) of the circumcircles of triangles \( ABD \) and \( ACD \), respectively. Prove that the circumcircle of triangle \( PQD \) passes through a fixed point, independent of the choice of \( D \) on \( BC \).
0 replies
Assassino9931
4 minutes ago
0 replies
J
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Train yourself on folklore NT FE ideas
Assassino9931   0
7 minutes ago
Source: Bulgaria Spring Mathematical Competition 9.4
Determine all functions $f: \mathbb{Z}_{>0} \to \mathbb{Z}_{>0}$ such that $f(a) + 2ab + 2f(b)$ divides $f(a)^2 + 4f(b)^2$ for any positive integers $a$ and $b$.
0 replies
+2 w
Assassino9931
7 minutes ago
0 replies
J
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Spanning tree preserving a dominating set
Assassino9931   0
9 minutes ago
Source: Bulgaria Spring Mathematical Competition 9.3
In a country, there are towns, some of which are connected by roads. There is a route (not necessarily direct) between every two towns. The Minister of Education has ensured that every town without a school is connected via a direct road to a town that has a school. The Minister of State Optimization wants to ensure that there is a unique path between any two towns (without repeating traveled segments), which may require removing some roads.

Is it always possible to achieve this without constructing additional schools while preserving what the Minister of Education has accomplished?
0 replies
Assassino9931
9 minutes ago
0 replies
J
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Python exit() module decriptions appear as "undefined"
SoaringHigh   11
N Friday at 8:45 PM by bpan2021
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
11 replies
SoaringHigh
Oct 22, 2024
bpan2021
Friday at 8:45 PM
J
H
k Aops Glitching
jkim0656   26
N Mar 27, 2025 by jlacosta
Hi everyone!
I noticed that every time i try to answer a question and get it right/wrong the screen freezes and i can't scroll anymore...
100%
Chrome
PC
do u guys have the same issue?
I don't think it is like this for Alcumus but for normal class problems it does
*the challenge problems

EDIT: sry for the terrible title :blush:
26 replies
jkim0656
Mar 27, 2025
jlacosta
Mar 27, 2025
J
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k New reaper game
Squidget   10
N Mar 27, 2025 by Cerberusman
What does this mean?

Is this a glitch
10 replies
Squidget
Mar 26, 2025
Cerberusman
Mar 27, 2025
J
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k Office Hours not starting yet?
GAMER100   5
N Mar 27, 2025 by Demetri
Several posts have been made about this years before, but the office hours banner hasn't appeared yet even though I refreshed the page multiple times. It has been 50 minutes since when office hours should have started and no mods have responded to a question I posted 3 hours ago (relative to last edit). Can others confirm?
5 replies
GAMER100
Mar 24, 2025
Demetri
Mar 27, 2025
J
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k AoPS wiki loading slowly?
EaZ_Shadow   18
N Mar 26, 2025 by jlacosta
I don't know why, but why is that when I try loading to AoPS Wiki, it loads really slow? (I'm using an iPad)
18 replies
EaZ_Shadow
Mar 25, 2025
jlacosta
Mar 26, 2025
J
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k weird bug
maxamc   1
N Mar 26, 2025 by Craftybutterfly
I could not view any forums or blogs for the last 20 minutes and thought I was postbanned (I tried clearing cache and nothing happened). Now it works.
1 reply
maxamc
Mar 26, 2025
Craftybutterfly
Mar 26, 2025
J
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k Staff, Please confirm or deny this conjecture
Mango8000   2
N Mar 25, 2025 by jlacosta
It’s seems that there are suspicions about AoPS selling Beast Academy to another company. Is that true? Becuase AoPS online and Beast Academy are connected and it will affect us. I hope that AoPS decides to keep it, but if not, there really isn’t anything we can do.
2 replies
Mango8000
Mar 24, 2025
jlacosta
Mar 25, 2025
J
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k spotted in blogroll
Major_Monogram   8
N Mar 25, 2025 by Embershed97
I saw this on the AoPS Blogroll. closing it, the page worked normally.
8 replies
Major_Monogram
Mar 22, 2025
Embershed97
Mar 25, 2025
J
H
k The avatars are not consistent
Craftybutterfly   45
N Mar 24, 2025 by Demetri
Summary of the problem: The avatars are not consistent
Page URL: idk
Steps to reproduce:
1. change your avatar
2.reload a topic you posted in
3. do #2 to a different topic with your post in it
Expected behavior: Avatars are the same
Frequency: 100%
Operating system(s): MacOS
Browser(s), including version: Chrome latest version
Additional information: refreshing does not help, neither does logging out and in
45 replies
Craftybutterfly
Mar 20, 2025
Demetri
Mar 24, 2025
J
H
k Mr. Rusczyk is retiring!
SmartGroot   58
N Mar 24, 2025 by AmethystC
Has anyone else got the email? Mr. Rusczyks retiring :o
58 replies
SmartGroot
Mar 24, 2025
AmethystC
Mar 24, 2025
J
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J
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Maximum angle
LlynX   1
N Jun 12, 2015 by Virgil Nicula
Peter and Jane begin running along a straight track starting from point $ O $, while Lily looks on at the side. The diagram shows a particular instant when Peter, Lily and Jane are at $ A $, $ B $ and $ C $ respectively. Given that Peter runs 3 times faster than Jane, and $ \angle AOB = 90^{\circ} $, find the maximum value of Lily's angle of sight, i.e. $ \angle ABC $, between the two runners.
1 reply
LlynX
Jun 11, 2015
Virgil Nicula
Jun 12, 2015
J
Maximum angle
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Reveal topic tags
geometry
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LlynX
150 posts
LlynX
#1 h  Jun 11, 2015, 2:46 PM • 1 Y
Y by Adventure10
Peter and Jane begin running along a straight track starting from point $ O $, while Lily looks on at the side. The diagram shows a particular instant when Peter, Lily and Jane are at $ A $, $ B $ and $ C $ respectively. Given that Peter runs 3 times faster than Jane, and $ \angle AOB = 90^{\circ} $, find the maximum value of Lily's angle of sight, i.e. $ \angle ABC $, between the two runners.
Attachments:
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Virgil Nicula
7054 posts
Virgil Nicula
#2 h  Jun 12, 2015, 11:04 PM • 2 Y
Y by Adventure10, Mango247
See here the problem PE12 with two proofs.
This post has been edited 2 times. Last edited by Virgil Nicula, Jun 23, 2015, 4:31 PM
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