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k a May Highlights and 2025 AoPS Online Class Information
jlacosta   0
Thursday at 11:16 PM
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.

Introductory: Grades 5-10

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0 replies
jlacosta
Thursday at 11:16 PM
0 replies
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k i Adding contests to the Contest Collections
dcouchman   1
N Apr 5, 2023 by v_Enhance
Want to help AoPS remain a valuable Olympiad resource? Help us add contests to AoPS's Contest Collections.

Find instructions and a list of contests to add here: https://artofproblemsolving.com/community/c40244h1064480_contests_to_add
1 reply
dcouchman
Sep 9, 2019
v_Enhance
Apr 5, 2023
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k i Zero tolerance
ZetaX   49
N May 4, 2019 by NoDealsHere
Source: Use your common sense! (enough is enough)
Some users don't want to learn, some other simply ignore advises.
But please follow the following guideline:


To make it short: ALWAYS USE YOUR COMMON SENSE IF POSTING!
If you don't have common sense, don't post.


More specifically:

For new threads:


a) Good, meaningful title:
The title has to say what the problem is about in best way possible.
If that title occured already, it's definitely bad. And contest names aren't good either.
That's in fact a requirement for being able to search old problems.

Examples:
Bad titles:
- "Hard"/"Medium"/"Easy" (if you find it so cool how hard/easy it is, tell it in the post and use a title that tells us the problem)
- "Number Theory" (hey guy, guess why this forum's named that way¿ and is it the only such problem on earth¿)
- "Fibonacci" (there are millions of Fibonacci problems out there, all posted and named the same...)
- "Chinese TST 2003" (does this say anything about the problem¿)
Good titles:
- "On divisors of a³+2b³+4c³-6abc"
- "Number of solutions to x²+y²=6z²"
- "Fibonacci numbers are never squares"


b) Use search function:
Before posting a "new" problem spend at least two, better five, minutes to look if this problem was posted before. If it was, don't repost it. If you have anything important to say on topic, post it in one of the older threads.
If the thread is locked cause of this, use search function.

Update (by Amir Hossein). The best way to search for two keywords in AoPS is to input
[code]+"first keyword" +"second keyword"[/code]
so that any post containing both strings "first word" and "second form".


c) Good problem statement:
Some recent really bad post was:
[quote]$lim_{n\to 1}^{+\infty}\frac{1}{n}-lnn$[/quote]
It contains no question and no answer.
If you do this, too, you are on the best way to get your thread deleted. Write everything clearly, define where your variables come from (and define the "natural" numbers if used). Additionally read your post at least twice before submitting. After you sent it, read it again and use the Edit-Button if necessary to correct errors.


For answers to already existing threads:


d) Of any interest and with content:
Don't post things that are more trivial than completely obvious. For example, if the question is to solve $x^{3}+y^{3}=z^{3}$, do not answer with "$x=y=z=0$ is a solution" only. Either you post any kind of proof or at least something unexpected (like "$x=1337, y=481, z=42$ is the smallest solution). Someone that does not see that $x=y=z=0$ is a solution of the above without your post is completely wrong here, this is an IMO-level forum.
Similar, posting "I have solved this problem" but not posting anything else is not welcome; it even looks that you just want to show off what a genius you are.

e) Well written and checked answers:
Like c) for new threads, check your solutions at least twice for mistakes. And after sending, read it again and use the Edit-Button if necessary to correct errors.



To repeat it: ALWAYS USE YOUR COMMON SENSE IF POSTING!


Everything definitely out of range of common sense will be locked or deleted (exept for new users having less than about 42 posts, they are newbies and need/get some time to learn).

The above rules will be applied from next monday (5. march of 2007).
Feel free to discuss on this here.
49 replies
ZetaX
Feb 27, 2007
NoDealsHere
May 4, 2019
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Aops is malware
Speedysolver1   20
N 15 minutes ago by Demetri
See the image they are trying to track me
20 replies
Speedysolver1
Yesterday at 10:51 PM
Demetri
15 minutes ago
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Introducing myself at AoPS, and what's your magic wand?
asuth_asuth   1096
N 33 minutes ago by PikaPika999
Hi!

I'm Andrew Sutherland. I'm the new Chief Product Officer at AoPS. As you may have read, Richard is retiring and Ben Kornell and I are working together to lead the company now. I'm leading all the software and digital stuff at AoPS. I just wanted to say hello and introduce myself! I'm really excited to be part of the special community that is AoPS.

Previously, I founded Quizlet as a 15-year-old high school student. I did Course 6 at MIT and then left to lead Quizlet full-time for a total of 14 years. I took a few years off and now I'm doing AoPS! I wrote more about all that on my blog: https://asuth.com/im-joining-aops

I have a question for all of you. If you could wave a magic wand, and change anything about AoPS, what would it be? All suggestions welcome! Thank you.
1096 replies
asuth_asuth
Mar 30, 2025
PikaPika999
33 minutes ago
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Solution needed ASAP
UglyScientist   8
N an hour ago by deltapc
$ABC$ is acute triangle. $H$ is orthocenter, $M$ is the midpoint of $BC$, $L$ is the midpoint of smaller arc $BC$. Point $K$ is on $AH$ such that, $MK$ is perpendicular to $AL$. Prove that: $HMLK$ is paralelogram(Synthetic sol needed).
8 replies
UglyScientist
5 hours ago
deltapc
an hour ago
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BMO 2024 SL C1
GreekIdiot   11
N an hour ago by cursed_tangent1434
Let $n$, $k$ be positive integers. Julia and Florian play a game on a $2n \times 2n$ board. Julia
has secretly tiled the entire board with invisible dominos. Florian now chooses $k$ cells.
All dominos covering at least one of these cells then turn visible. Determine the minimal
value of $k$ such that Florian has a strategy to always deduce the entire tiling.
11 replies
GreekIdiot
Apr 27, 2025
cursed_tangent1434
an hour ago
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Cyclic quadrilateral and a tangent
a_507_bc   6
N an hour ago by User141208
Source: IMOC 2023 G6
Triangle $ABC$ has circumcenter $O$. $D$ is the foot from $A$ to $BC$, and $P$ is apoint on $AD$. The feet from $P$ to $CA, AB$ are $E, F$, respectively, and the foot from $D$ to $EF$ is $T$. $AO$ meets $(ABC)$ again at $A'$. $A'D$ meets $(ABC)$ again at $R$. If $Q$ is a point on $AO$ satisfying $\angle ABP = \angle QBC$, prove that $D, P, T, R$ lie on acircle and $DQ$ is tangent to it.
6 replies
a_507_bc
Sep 9, 2023
User141208
an hour ago
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Geometry
blug   0
an hour ago
Source: own
Let $O$ be a point inside triangle $ABC$. Let $p, q$ be lines passint trough $O, AB, AC$. We denote $K=p\cap AB, L=p\cap AC, M=q\cap AC, N=q\cap AB$. Circumcircles of $NKO$ and $MOL$ intersect at $P\ne O$. Prove that
$$\angle BAC=\angle PKL+\angle PMN.$$
0 replies
blug
an hour ago
0 replies
J
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Random modulos
m4thbl3nd3r   5
N 2 hours ago by Drakkur
Find all pair of integers $(x,y)$ s.t $x^2+3=y^7$
5 replies
m4thbl3nd3r
Apr 7, 2025
Drakkur
2 hours ago
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XZ passes through the midpoint of BK, isosceles, KX = CX, angle bisector
parmenides51   5
N 2 hours ago by Kyj9981
Source: 1st Girls in Mathematics Tournament 2019 p5 (Brazil) / Torneio Meninas na Matematica (TM^2 )
Let $ABC$ be an isosceles triangle with $AB = AC$. Let $X$ and $K$ points over $AC$ and $AB$, respectively, such that $KX = CX$. Bisector of $\angle AKX$ intersects line $BC$ at $Z$. Show that $XZ$ passes through the midpoint of $BK$.
5 replies
parmenides51
May 25, 2020
Kyj9981
2 hours ago
J
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Diophantine Equation with prime numbers and bonus conditions
p.lazarov06   10
N 2 hours ago by mathbetter
Source: 2023 Bulgaria JBMO TST Problem 3
Find all natural numbers $a$, $b$, $c$ and prime numbers $p$ and $q$, such that:

$\blacksquare$ $4\nmid c$
$\blacksquare$ $p\not\equiv 11\pmod{16}$
$\blacksquare$ $p^aq^b-1=(p+4)^c$
10 replies
+1 w
p.lazarov06
May 7, 2023
mathbetter
2 hours ago
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Concurrence in Cyclic Quadrilateral
GrantStar   39
N 2 hours ago by ItsBesi
Source: IMO Shortlist 2023 G3
Let $ABCD$ be a cyclic quadrilateral with $\angle BAD < \angle ADC$. Let $M$ be the midpoint of the arc $CD$ not containing $A$. Suppose there is a point $P$ inside $ABCD$ such that $\angle ADB = \angle CPD$ and $\angle ADP = \angle PCB$.

Prove that lines $AD, PM$, and $BC$ are concurrent.
39 replies
GrantStar
Jul 17, 2024
ItsBesi
2 hours ago
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IMO Genre Predictions
ohiorizzler1434   22
N 2 hours ago by rhydon516
Everybody, with IMO upcoming, what are you predictions for the problem genres?


Personally I predict: predict
22 replies
ohiorizzler1434
Today at 6:51 AM
rhydon516
2 hours ago
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Inequality
MathsII-enjoy   1
N 3 hours ago by arqady
A interesting problem generalized :-D
1 reply
MathsII-enjoy
4 hours ago
arqady
3 hours ago
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Reply box disappearing
Craftybutterfly   16
N Yesterday at 10:15 PM by Craftybutterfly
For some reason, on my iPhone XR, when I press on the view my posts button, then press on an unlocked topic and scroll down or press go down button, the reply box disappears. I can’t use the proper format right now as I am on phone.
Summary of the problem: the lines above
setps to reproduce:
1. Go to your profile
2. Press on your posts button
3. press an unlocked topic and scroll down
Frequency: 100%
Browser: Chrome latest version
Device: iPhone XR
16 replies
Craftybutterfly
Apr 30, 2025
Craftybutterfly
Yesterday at 10:15 PM
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Cannot post PHP
char0221   4
N Yesterday at 1:02 PM by k1glaucus
Summary of the problem: If I try to post anything with PHP (a coding language), it
Page URL: In any forum or private messages
Steps to reproduce:
1. Create a post.
2. Put some PHP inside, can't give example
Expected behavior: Should post the message
Frequency: 100%
Operating system(s): macOS Sequoia 15.2.1
Browser(s), including version: Safari
Additional information: See attachments
4 replies
char0221
Apr 30, 2025
k1glaucus
Yesterday at 1:02 PM
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k Image Posting for New Users
Alpaca31415   4
N Apr 15, 2025 by RedChameleon
Hello there, Im getting an error that says new community users are not allowed to post images. I only had latex code, no images, so Im confused on what I should do now.
4 replies
Alpaca31415
Apr 15, 2025
RedChameleon
Apr 15, 2025
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Image Posting for New Users
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Reveal topic tags
Question about images
LaTeX
new users
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Alpaca31415
12 posts
Alpaca31415
#1 h  Apr 15, 2025, 4:25 AM
Y by
Hello there, Im getting an error that says new community users are not allowed to post images. I only had latex code, no images, so Im confused on what I should do now.
Z Y
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aidan0626
1886 posts
aidan0626
#2 h  Apr 15, 2025, 4:31 AM
Y by
LaTeX code counts as images, and so you will not be allowed to use LaTeX until the new user restrictions are lifted.
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Alpaca31415
12 posts
Alpaca31415
#3 h  Apr 15, 2025, 4:32 AM
Y by
When would that be?
Z Y
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aidan0626
1886 posts
aidan0626
#4 h  Apr 15, 2025, 4:39 AM
Y by
I believe you have to be active for 2 weeks for the restrictions to be lifted.
Z Y
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RedChameleon
1239 posts
RedChameleon
#5 h  Apr 15, 2025, 4:53 AM
Y by
Alpaca31415 wrote:
When would that be?

New users also cannot post more than 6 times a day.
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