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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.

Introductory: Grades 5-10

Prealgebra 1 Self-Paced

Prealgebra 1
Tuesday, May 13 - Aug 26
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Prealgebra 2 Self-Paced

Prealgebra 2
Wednesday, May 7 - Aug 20
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Introduction to Algebra A Self-Paced

Introduction to Algebra A
Sunday, May 11 - Sep 14 (1:00 - 2:30 pm ET/10:00 - 11:30 am PT)
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Introduction to Counting & Probability Self-Paced

Introduction to Counting & Probability
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Introduction to Number Theory
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Introduction to Algebra B Self-Paced

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Paradoxes and Infinity
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Intermediate: Grades 8-12

Intermediate Algebra
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Precalculus
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Advanced: Grades 9-12

Olympiad Geometry
Tuesday, Jun 10 - Aug 26

Calculus
Tuesday, May 27 - Nov 11
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Group Theory
Thursday, Jun 12 - Sep 11

Contest Preparation: Grades 6-12

MATHCOUNTS/AMC 8 Basics
Friday, May 23 - Aug 15
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Tues & Thurs, Jul 8 - Aug 14 (meets twice a week!)

MATHCOUNTS/AMC 8 Advanced
Sunday, May 11 - Aug 10
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Thursday, May 22 - Jul 31

AIME Problem Series B
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Visit the pages linked for full schedule details for each of these programs!


MathWOOT Level 1
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Programming

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Physics

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Physics 1: Mechanics
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Relativity
Mon, Tue, Wed & Thurs, Jun 23 - Jun 26 (meets every day of the week!)
0 replies
jlacosta
May 1, 2025
0 replies
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
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
Introducing myself at AoPS, and what's your magic wand?
asuth_asuth   1158
N 10 minutes ago by LuminousWolverine
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.
1158 replies
+1 w
asuth_asuth
Mar 30, 2025
LuminousWolverine
10 minutes ago
Chinese Girls Mathematical Olympiad 2017, Problem 7
Hermitianism   45
N 2 hours ago by Ilikeminecraft
Source: Chinese Girls Mathematical Olympiad 2017, Problem 7
This is a very classical problem.
Let the $ABCD$ be a cyclic quadrilateral with circumcircle $\omega_1$.Lines $AC$ and $BD$ intersect at point $E$,and lines $AD$,$BC$ intersect at point $F$.Circle $\omega_2$ is tangent to segments $EB,EC$ at points $M,N$ respectively,and intersects with circle $\omega_1$ at points $Q,R$.Lines $BC,AD$ intersect line $MN$ at $S,T$ respectively.Show that $Q,R,S,T$ are concyclic.
45 replies
Hermitianism
Aug 16, 2017
Ilikeminecraft
2 hours ago
D1031 : A general result on polynomial 1
Dattier   1
N 2 hours ago by Dattier
Source: les dattes à Dattier
Let $P(x,y) \in \mathbb Q(x,y)$ with $\forall (a,b) \in \mathbb Z^2, P(a,b) \in \mathbb Z  $.

Is it true that $P(x,y) \in \mathbb Q[x,y]$?
1 reply
Dattier
5 hours ago
Dattier
2 hours ago
Asymmetric FE
sman96   18
N 2 hours ago by jasperE3
Source: BdMO 2025 Higher Secondary P8
Find all functions $f: \mathbb{R} \to \mathbb{R}$ such that$$f(xf(y)-y) + f(xy-x) + f(x+y) = 2xy$$for all $x, y \in \mathbb{R}$.
18 replies
sman96
Feb 8, 2025
jasperE3
2 hours ago
Easy Geometry
pokmui9909   6
N 2 hours ago by reni_wee
Source: FKMO 2025 P4
Triangle $ABC$ satisfies $\overline{CA} > \overline{AB}$. Let the incenter of triangle $ABC$ be $\omega$, which touches $BC, CA, AB$ at $D, E, F$, respectively. Let $M$ be the midpoint of $BC$. Let the circle centered at $M$ passing through $D$ intersect $DE, DF$ at $P(\neq D), Q(\neq D)$, respecively. Let line $AP$ meet $BC$ at $N$, line $BP$ meet $CA$ at $L$. Prove that the three lines $EQ, FP, NL$ are concurrent.
6 replies
pokmui9909
Mar 30, 2025
reni_wee
2 hours ago
Old hard problem
ItzsleepyXD   3
N 3 hours ago by Funcshun840
Source: IDK
Let $ABC$ be a triangle and let $O$ be its circumcenter and $I$ its incenter.
Let $P$ be the radical center of its three mixtilinears and let $Q$ be the isogonal conjugate of $P$.
Let $G$ be the Gergonne point of the triangle $ABC$.
Prove that line $QG$ is parallel with line $OI$ .
3 replies
ItzsleepyXD
Apr 25, 2025
Funcshun840
3 hours ago
\frac{2^{n!}-1}{2^n-1} be a square
AlperenINAN   10
N 3 hours ago by Nuran2010
Source: Turkey JBMO TST 2024 P5
Find all positive integer values of $n$ such that the value of the
$$\frac{2^{n!}-1}{2^n-1}$$is a square of an integer.
10 replies
AlperenINAN
May 13, 2024
Nuran2010
3 hours ago
Beautiful Angle Sum Property in Hexagon with Incenter
Raufrahim68   0
4 hours ago
Hello everyone! I discovered an interesting geometric property and would like to share it with the community. I'm curious if this is a known result and whether it can be generalized.

Problem Statement:
Let
A
B
C
D
E
K
ABCDEK be a convex hexagon with an incircle centered at
O
O. Prove that:


A
O
B
+

C
O
D
+

E
O
K
=
180

∠AOB+∠COD+∠EOK=180
0 replies
Raufrahim68
4 hours ago
0 replies
Anything real in this system must be integer
Assassino9931   7
N 4 hours ago by Leman_Nabiyeva
Source: Al-Khwarizmi International Junior Olympiad 2025 P1
Determine the largest integer $c$ for which the following statement holds: there exists at least one triple $(x,y,z)$ of integers such that
\begin{align*} x^2 + 4(y + z) = y^2 + 4(z + x) = z^2 + 4(x + y) = c \end{align*}and all triples $(x,y,z)$ of real numbers, satisfying the equations, are such that $x,y,z$ are integers.

Marek Maruin, Slovakia
7 replies
Assassino9931
May 9, 2025
Leman_Nabiyeva
4 hours ago
CIIM 2011 First day problem 3
Ozc   2
N 4 hours ago by pi_quadrat_sechstel
Source: CIIM 2011
Let $f(x)$ be a rational function with complex coefficients whose denominator does not have multiple roots. Let $u_0, u_1,... , u_n$ be the complex roots of $f$ and $w_1, w_2,..., w_m$ be the roots of $f'$. Suppose that $u_0$ is a simple root of $f$. Prove that
\[ \sum_{k=1}^m \frac{1}{w_k - u_0} = 2\sum_{k = 1}^n\frac{1}{u_k - u_0}.\]
2 replies
Ozc
Oct 3, 2014
pi_quadrat_sechstel
4 hours ago
IMO 2009 P2, but in space
Miquel-point   1
N 4 hours ago by Miquel-point
Source: KoMaL A. 485
Let $ABCD$ be a tetrahedron with circumcenter $O$. Suppose that the points $P, Q$ and $R$ are interior points of the edges $AB, AC$ and $AD$, respectively. Let $K, L, M$ and $N$ be the centroids of the triangles $PQD$, $PRC,$ $QRB$ and $PQR$, respectively. Prove that if the plane $PQR$ is tangent to the sphere $KLMN$ then $OP=OQ=OR.$

1 reply
Miquel-point
4 hours ago
Miquel-point
4 hours ago
k Glitch or Bug?
awesometriangles   5
N Today at 4:18 AM by Craftybutterfly
I was asking for some $\LaTeX$ help in one of my classrooms, and one of the Halpers posted. Is this a glitch or a bug(see screenshot)?


It seems as though I can edit their post...
5 replies
awesometriangles
Today at 1:08 AM
Craftybutterfly
Today at 4:18 AM
k Deleting collections
Sadigly   1
N May 12, 2025 by jlacosta
How to delete some collections? I accidently created 2 same collections, and one of them is useless
1 reply
Sadigly
May 11, 2025
jlacosta
May 12, 2025
k Alcumus Reset
greenplanet2050   7
N May 12, 2025 by jlacosta
I want to reset my Alcumus but it says "You cannot reset your Alcumus data while you are in current AoPS classes."

But I don't have any ongoing AoPs classes and my last class Precalculus already ended.
7 replies
greenplanet2050
May 10, 2025
jlacosta
May 12, 2025
k How to delete my post easily?
whwlqkd   17
N Apr 7, 2025 by whwlqkd
How to delete my post(trash) easily and fast?
17 replies
whwlqkd
Apr 6, 2025
whwlqkd
Apr 7, 2025
How to delete my post easily?
G H J
G H BBookmark kLocked kLocked NReply
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whwlqkd
103 posts
#1 • 1 Y
Y by PikaPika999
How to delete my post(trash) easily and fast?
Z Y
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EaZ_Shadow
1270 posts
#2 • 1 Y
Y by PikaPika999
U cant. Once someone post after you, you can only edit
Z Y
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SomeonecoolLovesMaths
3256 posts
#3 • 1 Y
Y by PikaPika999
Ask the mods ig
Z Y
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TeddySava
69 posts
#4 • 1 Y
Y by PikaPika999
Can you edit somebody else's post?
Z Y
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SomeonecoolLovesMaths
3256 posts
#5 • 1 Y
Y by PikaPika999
TeddySava wrote:
Can you edit somebody else's post?

A mod can
Z Y
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Skandaharini
54 posts
#6 • 1 Y
Y by PikaPika999
How do you edit your post
Z Y
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Skandaharini
54 posts
#7 • 1 Y
Y by PikaPika999
Can you delete your post if no one posts anything after you
Z Y
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Craftybutterfly
505 posts
#8 • 1 Y
Y by PikaPika999
Ask mod or admin to do it unless your one
Z Y
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MathWinner121
525 posts
#9 • 1 Y
Y by PikaPika999
you can edit, delete the words, and type redacted
Z Y
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SomeonecoolLovesMaths
3256 posts
#10 • 1 Y
Y by PikaPika999
Skandaharini wrote:
How do you edit your post

By clicking the pencil like button in place of the like button.
Z Y
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SomeonecoolLovesMaths
3256 posts
#11 • 1 Y
Y by PikaPika999
Skandaharini wrote:
Can you delete your post if no one posts anything after you

Yes, for a certain period of time. I guess you cannot anymore after a certain amount of time has passed, I forgot how much tho.
Z Y
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Craftybutterfly
505 posts
#12 • 1 Y
Y by PikaPika999
SomeonecoolLovesMaths wrote:
Skandaharini wrote:
Can you delete your post if no one posts anything after you

Yes, for a certain period of time. I guess you cannot anymore after a certain amount of time has passed, I forgot how much tho.

Until someone posts after you
Z Y
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AlienGirl05
11851 posts
#13 • 2 Y
Y by PikaPika999, whwlqkd
How to delete my post(trash) easily and fast?

Report your post, and ask AoPSSheriff to delete it. :)
Z Y
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K124659
2628 posts
#14 • 3 Y
Y by PikaPika999, AlienGirl05, whwlqkd
An alternate way is that if you want to delete a post for the purpose of solely redacting its contents, you can just edit the post, delete what you originally said, and input a text like "redacted" or "$~~~~~~~~~~~~~$"
Z Y
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AlienGirl05
11851 posts
#15 • 1 Y
Y by CoolBroCubby
An alternate way is that if you want to delete a post for the purpose of solely redacting its contents, you can just edit the post, delete what you originally said, and input a text like "redacted" or "$~~~~~~~~~~~~~$"

Note: That only works when the thread in question is not locked. :)
This post has been edited 1 time. Last edited by AlienGirl05, Apr 6, 2025, 8:33 PM
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HacheB2031
396 posts
#17
Y by
HacheB2031 wrote:
Post Here! (sorry for bump) (#16)

This post doesn't exist anymore. @bove is #15 and this is #17. Is this what you mean by deleting posts? EDIT: oh wait posts that have a post after them can't be deleted
This post has been edited 3 times. Last edited by HacheB2031, Apr 6, 2025, 11:32 PM
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Skandaharini
54 posts
#19
Y by
ok thank you for answering my questions :)
This post has been edited 1 time. Last edited by Skandaharini, Apr 7, 2025, 12:54 AM
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whwlqkd
103 posts
#20
Y by
AlienGirl05 wrote:
How to delete my post(trash) easily and fast?

Report your post, and ask AoPSSheriff to delete it. :)

What a elegant way!!!
Z Y
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a