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H
k a My Retirement & New Leadership at AoPS
rrusczyk   1573
N Yesterday at 11:40 PM 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
1573 replies
rrusczyk
Mar 24, 2025
SmartGroot
Yesterday at 11:40 PM
J
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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

Prealgebra 1 Self-Paced

Prealgebra 1
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Prealgebra 2 Self-Paced

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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Introduction to Algebra B Self-Paced

Introduction to Algebra B
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Intermediate Algebra
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Intermediate Counting & Probability
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Olympiad Geometry
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Calculus
Sunday, Mar 30 - Oct 5
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Group Theory
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Contest Preparation: Grades 6-12

MATHCOUNTS/AMC 8 Basics
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WOOT Programs
Visit the pages linked for full schedule details for each of these programs!

MathWOOT Level 1
MathWOOT Level 2
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Introduction to Programming with Python
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Relativity
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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
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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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Geometry Problem in Taiwan TST
chengbilly   2
N 32 minutes ago by Li4
Source: 2025 Taiwan TST Round 2 Independent Study 2-G
Given a triangle $ABC$ with circumcircle $\Gamma$, and two arbitrary points $X, Y$ on $\Gamma$. Let $D$, $E$, $F$ be points on lines $BC$, $CA$, $AB$, respectively, such that $AD$, $BE$, and $CF$ concur at a point $P$. Let $U$ be a point on line $BC$ such that $X$, $Y$, $D$, $U$ are concyclic. Similarly, let $V$ be a point on line $CA$ such that $X$, $Y$, $E$, $V$ are concyclic, and let $W$ be a point on line $AB$ such that $X$, $Y$, $F$, $W$ are concyclic. Prove that $AU$, $BV$, $CW$ concur at a single point.

Proposed by chengbilly
2 replies
chengbilly
2 hours ago
Li4
32 minutes ago
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Something nice
KhuongTrang   24
N 36 minutes ago by Nguyenhuyen_AG
Source: own
Problem. Given $a,b,c$ be non-negative real numbers such that $ab+bc+ca=1.$ Prove that

$$\sqrt{a+1}+\sqrt{b+1}+\sqrt{c+1}\le 1+2\sqrt{a+b+c+abc}.$$
24 replies
KhuongTrang
Nov 1, 2023
Nguyenhuyen_AG
36 minutes ago
J
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a+b+c=3 inequality
jokehim   0
an hour ago
Source: my problem
Let $a,b,c\ge 0: a+b+c=3.$ Prove that $$a\sqrt{bc+3}+b\sqrt{ca+3}+c\sqrt{ab+3}\ge \sqrt{12(ab+bc+ca)}.$$
0 replies
jokehim
an hour ago
0 replies
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Incenter perpendiculars and angle congruences
math154   83
N an hour ago by Ilikeminecraft
Source: ELMO Shortlist 2012, G3
$ABC$ is a triangle with incenter $I$. The foot of the perpendicular from $I$ to $BC$ is $D$, and the foot of the perpendicular from $I$ to $AD$ is $P$. Prove that $\angle BPD = \angle DPC$.

Alex Zhu.
83 replies
math154
Jul 2, 2012
Ilikeminecraft
an hour ago
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Office Hours not starting yet?
GAMER100   4
N 6 hours ago by jkim0656
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?
4 replies
GAMER100
Mar 24, 2025
jkim0656
6 hours ago
J
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k AoPS wiki loading slowly?
EaZ_Shadow   18
N Yesterday at 10:24 PM 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
Tuesday at 9:18 PM
jlacosta
Yesterday at 10:24 PM
J
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k weird bug
maxamc   1
N Yesterday at 7:32 PM 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
Yesterday at 6:12 PM
Craftybutterfly
Yesterday at 7:32 PM
J
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k Staff, Please confirm or deny this conjecture
Mango8000   2
N Tuesday at 4:37 PM 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
Tuesday at 4:37 PM
J
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k spotted in blogroll
Major_Monogram   8
N Tuesday at 1:06 PM by Embershed97
I saw this on the AoPS Blogroll. closing it, the page worked normally.
8 replies
Major_Monogram
Mar 22, 2025
Embershed97
Tuesday at 1:06 PM
J
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Pressing 'go down button' always creates a gray box on the last post
Craftybutterfly   20
N Mar 25, 2025 by Craftybutterfly
Summary of the problem: Pressing go down to last post button always creates a gray box overlapping last post
Page URL: any forum
Steps to reproduce:
1. Go to any topic in a forum
2. The gray box at the bottom overlaps part of the first post
Expected behavior: Should not show a gray box
Frequency: 100% of the time
Operating system(s): Linux HP EliteBook 835 G8 Notebook PC
Browser(s), including version: Chrome 133.0.6943.142 (Official Build) (64-bit) (cohort: Stable)
Additional information: It works on any other device, on my iPhone XR, a MacOS, and my iPad. Took the screenshot a month ago. The gray box still appears
20 replies
Craftybutterfly
Mar 12, 2025
Craftybutterfly
Mar 25, 2025
J
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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
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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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Python exit() module decriptions appear as "undefined"
SoaringHigh   8
N Mar 22, 2025 by Major_Monogram
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
8 replies
SoaringHigh
Oct 22, 2024
Major_Monogram
Mar 22, 2025
J
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Help about topics on alcumus
GreenBanana666   10
N Mar 22, 2025 by Major_Monogram
My ratio basics score used to be 99 a 5 days ago. But it is 84 now. What and why did that happen?


Now after one hour and zero questions done on Ratio basics, it has risen by 5 rating. :ewpu:
10 replies
GreenBanana666
Oct 29, 2024
Major_Monogram
Mar 22, 2025
J
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Very hard geometry
XAN4   1
N Mar 24, 2025 by Ritwin
Source: own
For $\triangle{ABC}$ and point $P$, if the cevian triangle and the pedal triangles of $P$ to $\triangle{ABC}$ are orthologic, then prove that the cevian triangle and the reflection triangle of $P$ to $\triangle{ABC}$ are also orthologic.
*Orthologic: Two triangles $\triangle{A_1B_1C_1}$ and $\triangle{A_2B_2C_2}$ are orthologic if the perpendiculars from the vertices $A_1$, $B_1$, $C_1$ on the sides $B_2C_2$, $A_2C_2$, and $A_2B_2$ are concurrent. Furthermore, if this is the case, then the perpendiculars from the vertices $A_2$, $B_2$, $C_2$ on the sides $B_1C_1$, $A_1C_1$, and $A_1B_1$ are also concurrent.
*reflection triangle: the triangle formed by the reflections of $P$ over $BC$, $CA$ and $AB$.
1 reply
XAN4
Mar 24, 2025
Ritwin
Mar 24, 2025
J
Very hard geometry
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Reveal topic tags
geometry
geometric transformation
reflection
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G H BBookmark kLocked kLocked NReply
Source: own
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XAN4
53 posts
XAN4
#1 h  Mar 24, 2025, 1:36 PM
Y by
For $\triangle{ABC}$ and point $P$, if the cevian triangle and the pedal triangles of $P$ to $\triangle{ABC}$ are orthologic, then prove that the cevian triangle and the reflection triangle of $P$ to $\triangle{ABC}$ are also orthologic.
*Orthologic: Two triangles $\triangle{A_1B_1C_1}$ and $\triangle{A_2B_2C_2}$ are orthologic if the perpendiculars from the vertices $A_1$, $B_1$, $C_1$ on the sides $B_2C_2$, $A_2C_2$, and $A_2B_2$ are concurrent. Furthermore, if this is the case, then the perpendiculars from the vertices $A_2$, $B_2$, $C_2$ on the sides $B_1C_1$, $A_1C_1$, and $A_1B_1$ are also concurrent.
*reflection triangle: the triangle formed by the reflections of $P$ over $BC$, $CA$ and $AB$.
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Ritwin
154 posts
Ritwin
#2 h  Mar 24, 2025, 4:07 PM
Y by
Doesn't this just follow from the fact that the pedal triangle and reflection triangle are homothetic (at $P$)? The corresponding perpendiculars in each orthology coincide.
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