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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.

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0 replies
jlacosta
Mar 2, 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
Binomial Summation
Saucepan_man02   0
an hour ago
Given that: $l_n = \sum_{r=1}^{n-1} \frac{2r^2-r(n-2)+1}{(n-r) \binom{n}{r}}$, find $l_{15}$.
0 replies
Saucepan_man02
an hour ago
0 replies
Inequality with integers and indices
Michael Niland   5
N an hour ago by ohiorizzler1434
Without using a calculator, show that $2^{\frac{1}{2}}$ $< 3^{\frac{1}{3}}$, and for a positive integer $n\geq3$, prove that

$n^{\frac{1}{n}}$ $>(n+1)^{\frac{1}{n+1}}$.
5 replies
1 viewing
Michael Niland
Yesterday at 6:52 AM
ohiorizzler1434
an hour ago
Quadratic Equation Problems
Saucepan_man02   4
N 2 hours ago by Saucepan_man02
P1) Let $\alpha < \beta <	\gamma$ be the roots of $ax^3+bx^2+cx+d=0$ with $7a+3b>0, 3a+2b<0$ and $\alpha(\beta+1)+\beta(\gamma+1)+\gamma(1+\alpha)=0$.
If [.] denotes the greatest integer function, then the number of possible values of $[|3 \alpha |] + [|6 \beta|] +
 [|9 \gamma |]$ is equal to
4 replies
Saucepan_man02
Mar 3, 2025
Saucepan_man02
2 hours ago
Fun combinatorics
MTA_2024   3
N 2 hours ago by Amkan2022
A chess master plays $no$ $less$ $than$ $1$ $game$ $per$ $day$ , but no more than $10$ $games$ $per$ $week$
Prove that, if he plays long enough, we can find a series of consecutive days in which the master played $exactly$ $23$ $games$.
3 replies
MTA_2024
Mar 13, 2025
Amkan2022
2 hours ago
Pressing &#039;go down button&#039; always creates a gray box on the last post
Craftybutterfly   17
N 3 hours ago 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
17 replies
Craftybutterfly
Mar 12, 2025
Craftybutterfly
3 hours ago
k Negative accuracy?
DarintheBoy   3
N 5 hours ago by DarintheBoy
Slow and Steady (Accuracy) I
Gain 100 Accuracy XP per day in each of the next 2 days. (-19 XP on day 1)

How did this happen? Has anyone else had this?
3 replies
DarintheBoy
5 hours ago
DarintheBoy
5 hours ago
k Writing Problem Extension
WildFitBrain   5
N Sunday at 7:00 PM by bpan2021
I already submitted an extension but I cannot edit it because I submitted an unfinished solution. I have not viewed the solution.
5 replies
WildFitBrain
Sunday at 6:12 PM
bpan2021
Sunday at 7:00 PM
k Happy Pi Day!
greenplanet2050   5
N Mar 15, 2025 by Yihangzh
Happy Pi Day! $3.141592653589793238462643383279 50288419716939937510 5820974944 5923078164062862089986280348253421170679$

:D :D :D :D
5 replies
greenplanet2050
Mar 15, 2025
Yihangzh
Mar 15, 2025
Contest collection PDFs don&#039;t work when LaTeX is embedded within BBCode
Equinox8   5
N Mar 14, 2025 by jlacosta
This could very well be reported before, however a quick search did not find anything.

While embedding LaTeX commands within BBCode (like this: [i]text $\dfrac{1}{2}$ text[/i]) typically displays as intended within a forum, trying to render a contest collection using these commands breaks the PDF renderer.
5 replies
Equinox8
Feb 26, 2025
jlacosta
Mar 14, 2025
k 2023 IMO
ostriches88   4
N Mar 14, 2025 by jlacosta
As outlined in this (locked) post, the forum/blog creation message is out of date. It has been over a year since that post, and it still has not changed. I don't know if this got lost somewhere in the "passing this along" chain or if it was determined to be irrelevant, but it seems like a relatively simple fix ;)
4 replies
ostriches88
Mar 10, 2025
jlacosta
Mar 14, 2025
k Somehow I broke the unique contest collection naming...
Equinox8   1
N Mar 14, 2025 by jlacosta
Somehow I broke the unique contest collection naming scheme; for what it's worth, I also ran into an AJAX timeout error while trying to make this particular post collection for the first time, and pressed "create" twice.

Not sure if there's anything to be done here, but are there potentially unforeseen consequences here?

https://artofproblemsolving.com/community/c4258765_2024_puerto_rico_team_selection_test (this is the one I'm working on; it's also not finished yet)
https://artofproblemsolving.com/community/c4258764_2024_puerto_rico_team_selection_test
1 reply
Equinox8
Mar 12, 2025
jlacosta
Mar 14, 2025
k New Forums Duplicates
k1glaucus   3
N Mar 14, 2025 by jlacosta
Summary of the problem: In the New Forums collection, many of the forums are duplicated, although some have slightly different information (likely due to the forum being edited by its admin(s)). Typically only one of the two has threads, and I believe this is the only way to access
Page URL: https://artofproblemsolving.com/community/c74_new_forums
Steps to reproduce:
1. Go to the link
2. You should see duplicates of some forums
Expected behavior: Each forum appears once
Frequency: Every time
Additional information: Typically only one of the two has threads, and from creating forums in the past I believe this is the only way to access the duplicate. Also not all of the forums are duplicated. Another reason to suspect these are duplicates are the forums with similar names have the same admin.
3 replies
k1glaucus
Mar 12, 2025
jlacosta
Mar 14, 2025
k Pi Day!!
SomeonecoolLovesMaths   66
N Mar 14, 2025 by LawofCosine
Happy $\pi$ day everyone!
66 replies
SomeonecoolLovesMaths
Mar 14, 2025
LawofCosine
Mar 14, 2025
k Help with beast academy
tyrantfire4   1
N Mar 14, 2025 by tyrantfire4
So my siblings do BA and it won't work if anyone can fix it that would be great!
All browers won't work
Apple and fire
Open BA account
1 reply
tyrantfire4
Mar 14, 2025
tyrantfire4
Mar 14, 2025
help me at this pls i'm so confused
myname17042005   12
N Yesterday at 3:07 AM by sqing
if a, b, c are real numbers and a, b, c >0, prove that
pls help meee
12 replies
myname17042005
Jun 12, 2020
sqing
Yesterday at 3:07 AM
help me at this pls i'm so confused
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G H BBookmark kLocked kLocked NReply
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myname17042005
2 posts
#1
Y by
if a, b, c are real numbers and a, b, c >0, prove that
pls help meee
Attachments:
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srisainandan6
2811 posts
#2 • 1 Y
Y by agentP
is this from asmp??
This post has been edited 1 time. Last edited by srisainandan6, Jun 12, 2020, 2:57 PM
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MPCO830
371 posts
#3
Y by
What is amsp?
Z K Y
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srisainandan6
2811 posts
#4 • 1 Y
Y by agentP
awesome math summer program
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myname17042005
2 posts
#5 • 1 Y
Y by Mango247
well i don't know what is amsp so i can't answer you this :((
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srisainandan6
2811 posts
#6 • 1 Y
Y by agentP
ok when dealing with inequalities, try to use these basic ones first:

AM GM
Cauchy (Titu's lemma in specific cases)
trivial inequality

which one do you think can be used
This post has been edited 1 time. Last edited by srisainandan6, Jun 12, 2020, 3:00 PM
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BobsonJoe
811 posts
#7
Y by
Just trivial inequality here.
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srisainandan6
2811 posts
#8 • 2 Y
Y by agentP, Mango247
yes, and from here you just want to algebraically manipulate this to get something in this form:
$(...)^2 + (...)^2 + .... + (....)^ 2$ $\ge$ $0$
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stacy2020
142 posts
#9
Y by
Content deleted.
This post has been edited 2 times. Last edited by stacy2020, Jun 12, 2020, 7:57 PM
Reason: correction
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pbj2006
439 posts
#10
Y by
Subtracting doesn't work like that for inequalities.
For example:
$5\geq4$
$3\geq -50$
Subtract to get $2\geq54$
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mathismyfav2020
23 posts
#12 • 1 Y
Y by Mango247
myname17042005 wrote:
if a, b, c are real numbers and a, b, c >0, prove that
pls help meee

my solution
Click to reveal hidden text
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DoThinh2001
404 posts
#13 • 1 Y
Y by Imayormaynotknowcalculus
myname17042005 wrote:
if a, b, c are real numbers and a, b, c >0, prove that
pls help meee
$$\dfrac{a^2}{b^2}+\dfrac{b^2}{c^2}+\dfrac{c^2}{a^2}\geq 2\left(\dfrac{a}{c}+\dfrac{b}{a}+\dfrac{c}{b}\right)-3$$
It's equivalent to prove that: $x^2+y^2+z^2+3\geq 2(xy+yz+zx)$, where $x,y,z>0$ such that $xyz=1$.
Since $3=\dfrac{9xyz}{3\sqrt[3]{xyz}}\geq \dfrac{9xyz}{x+y+z}$, it remains to show that:
$$x^2+y^2+z^2+\dfrac{9xyz}{x+y+z}\geq 2(xy+yz+zx)$$which is Schur's inequality.
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sqing
41050 posts
#14
Y by
DoThinh2001 wrote:
myname17042005 wrote:
if a, b, c are real numbers and a, b, c >0, prove that
pls help meee
$$\dfrac{a^2}{b^2}+\dfrac{b^2}{c^2}+\dfrac{c^2}{a^2}\geq 2\left(\dfrac{a}{c}+\dfrac{b}{a}+\dfrac{c}{b}\right)-3$$
It's equivalent to prove that: $x^2+y^2+z^2+3\geq 2(xy+yz+zx)$, where $x,y,z>0$ such that $xyz=1$.
Since $3=\dfrac{9xyz}{3\sqrt[3]{xyz}}\geq \dfrac{9xyz}{x+y+z}$, it remains to show that:
$$x^2+y^2+z^2+\dfrac{9xyz}{x+y+z}\geq 2(xy+yz+zx)$$which is Schur's inequality.
(MR J693)Let $ a,b,c>0 $ and $a+b+c=3abc . $ Prove that
$$a^2+b^2+c^2+3\geq 2(ab+bc+ca)$$$$\iff  a^2+b^2+c^2+\dfrac{9abc}{a+b+c}\geq 2(ab+bc+ca)$$https://artofproblemsolving.com/community/c6h483075p9470528
https://artofproblemsolving.com/community/c6h1562485p9562400
https://artofproblemsolving.com/community/c6h37173p565225
https://artofproblemsolving.com/community/c6h76676p17106912
Let $a$, $b$ and $c$ be positive numbers such that $ a^2+b^2+c^2+1=4a^2b^2c^2 $. Prove that
$$a^2+b^2+c^2+3\geq2(ab+ac+bc)$$
This post has been edited 2 times. Last edited by sqing, Yesterday at 3:13 AM
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