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Tech support and questions about AoPS classes and materials
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Site Support Tech support and questions about AoPS classes and materials
Tech support and questions about AoPS classes and materials
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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)
Wednesday, May 14 - Aug 27
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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

Introduction to Algebra B
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Mon, Tue, Wed, & Thurs, Jul 14 - Jul 16 (meets every day of the week!)

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
Wednesday, Jun 25 - Dec 17

Group Theory
Thursday, Jun 12 - Sep 11

Contest Preparation: Grades 6-12

MATHCOUNTS/AMC 8 Basics
Friday, May 23 - Aug 15
Monday, Jun 2 - Aug 18
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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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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
1 viewing
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
Upvotes Farming
tintin21   5
N 40 minutes ago by tintin21
HOW DOES THIS WORK???
5 replies
tintin21
Today at 3:10 AM
tintin21
40 minutes ago
Inequality conjecture
RainbowNeos   2
N an hour ago by RainbowNeos
Show (or deny) that there exists an absolute constant $C>0$ that, for all $n$ and $n$ positive real numbers $x_i ,1\leq i \leq n$, there is
\[\sum_{i=1}^n \frac{x_i^2}{\sum_{j=1}^i x_j}\geq C \ln n\left(\prod_{i=1}^n x_i\right)^{\frac{1}{n}}\]
2 replies
RainbowNeos
May 29, 2025
RainbowNeos
an hour ago
2- player game on a strip of n squares with two game pieces
parmenides51   2
N an hour ago by Gggvds1
Source: 2023 Austrian Mathematical Olympiad, Junior Regional Competition , Problem 3
Alice and Bob play a game on a strip of $n \ge  3$ squares with two game pieces. At the beginning, Alice’s piece is on the first square while Bob’s piece is on the last square. The figure shows the starting position for a strip of $ n = 7$ squares.
IMAGE
The players alternate. In each move, they advance their own game piece by one or two squares in the direction of the opponent’s piece. The piece has to land on an empty square without jumping over the opponent’s piece. Alice makes the first move with her own piece. If a player cannot move, they lose.

For which $n$ can Bob ensure a win no matter how Alice plays?
For which $n$ can Alice ensure a win no matter how Bob plays?

(Karl Czakler)
2 replies
parmenides51
Mar 26, 2024
Gggvds1
an hour ago
Incenters and Circles
rkm0959   6
N an hour ago by happypi31415
Source: Korean National Junior Olympiad Problem 1
In a triangle $\triangle ABC$ with incenter $I$,
Let $D$ = $AI$ $\cap$ $BC$
$E$ = incenter of $\triangle ABD$
$F$ = incenter of $\triangle ACD$
$P$ = intersection of $\odot BCE$ and $\overline {ED}$
$Q$ = intersection of $\odot BCF$ and $\overline {FD}$
$M$ = midpoint of $\overline {BC}$

Prove that $D, M, P, Q$ concycle
6 replies
rkm0959
Nov 2, 2014
happypi31415
an hour ago
Reflected point lies on radical axis
Mahdi_Mashayekhi   6
N an hour ago by khanhnx
Source: Iran 2025 second round P4
Given is an acute and scalene triangle $ABC$ with circumcenter $O$. $BO$ and $CO$ intersect the altitude from $A$ to $BC$ at points $P$ and $Q$ respectively. $X$ is the circumcenter of triangle $OPQ$ and $O'$ is the reflection of $O$ over $BC$. $Y$ is the second intersection of circumcircles of triangles $BXP$ and $CXQ$. Show that $X,Y,O'$ are collinear.
6 replies
Mahdi_Mashayekhi
Apr 19, 2025
khanhnx
an hour ago
Gcd of N and its coprime pair sum
EeEeRUT   19
N an hour ago by HamstPan38825
Source: EGMO 2025 P1
For a positive integer $N$, let $c_1 < c_2 < \cdots < c_m$ be all positive integers smaller than $N$ that are coprime to $N$. Find all $N \geqslant 3$ such that $$\gcd( N, c_i + c_{i+1}) \neq 1$$for all $1 \leqslant i \leqslant m-1$

Here $\gcd(a, b)$ is the largest positive integer that divides both $a$ and $b$. Integers $a$ and $b$ are coprime if $\gcd(a, b) = 1$.

Proposed by Paulius Aleknavičius, Lithuania
19 replies
+1 w
EeEeRUT
Apr 16, 2025
HamstPan38825
an hour ago
Question on Balkan SL
Fmimch   4
N an hour ago by BreezeCrowd
Does anyone know where to find the Balkan MO Shortlist 2024? If you have the file, could you send in this thread? Thank you!
4 replies
Fmimch
Apr 30, 2025
BreezeCrowd
an hour ago
(3^{p-1} - 1)/p is a perfect square for prime p
parmenides51   4
N an hour ago by Rayvhs
Source: 2017 Saudi Arabia JBMO TST 1.2
Find all prime numbers $p$ such that $\frac{3^{p-1} - 1}{p}$ is a perfect square.
4 replies
parmenides51
May 28, 2020
Rayvhs
an hour ago
Rays, incircle, angles...
mathisreal   3
N 2 hours ago by Assassino9931
Source: Rioplatense L-3 2022 #4
Let $ABC$ be a triangle with incenter $I$. Let $D$ be the point of intersection between the incircle and the side $BC$, the points $P$ and $Q$ are in the rays $IB$ and $IC$, respectively, such that $\angle IAP=\angle CAD$ and $\angle IAQ=\angle BAD$. Prove that $AP=AQ$.
3 replies
mathisreal
Dec 13, 2022
Assassino9931
2 hours ago
Find the value
sqing   0
2 hours ago
Source: Own
Let $ a,b $ be real numbers such that $ (a^2 + b^2) (a + 1) (b + 1) =  a ^ 3 + b ^ 3 =2 $. Find the value of $ a b .$

Let $ a,b $ be real numbers such that $ (a^2 + b^2) (a + 1) (b + 1) = 2 $ and $ a ^ 3 + b ^ 3 = 1 $. Find the value of $ a + b .$
0 replies
sqing
2 hours ago
0 replies
Wordy Geometry in Taiwan TST
ckliao914   9
N 2 hours ago by Scilyse
Source: 2023 Taiwan TST Round 3 Mock Exam 6
Given triangle $ABC$ with $A$-excenter $I_A$, the foot of the perpendicular from $I_A$ to $BC$ is $D$. Let the midpoint of segment $I_AD$ be $M$, $T$ lies on arc $BC$(not containing $A$) satisfying $\angle BAT=\angle DAC$, $I_AT$ intersects the circumcircle of $ABC$ at $S\neq T$. If $SM$ and $BC$ intersect at $X$, the perpendicular bisector of $AD$ intersects $AC,AB$ at $Y,Z$ respectively, prove that $AX,BY,CZ$ are concurrent.
9 replies
ckliao914
Apr 29, 2023
Scilyse
2 hours ago
grade report
evt917   0
Today at 1:00 AM
when you request the grade report in a class, does your grade reflect the grade when you requested the report? or does the final grade reflect the grade by the time the report is generated?

So for example if i request a report at 5-23-2025 and it comes back at 5-31-2025, does the final grade reflect the progress at 5-23-2025 or 5-31-2025?
0 replies
evt917
Today at 1:00 AM
0 replies
k Grey Avatars
CurlyFalcon55   2
N Yesterday at 11:15 PM by tintin21
Just a little question, what are the grey avatars for? :huh:

I don't understand what happened here either.
2 replies
CurlyFalcon55
Yesterday at 11:08 PM
tintin21
Yesterday at 11:15 PM
k [RESOLVED, LOCK PLEASE] Ratings not showing
AbhayAttarde01   3
N Yesterday at 8:55 PM by bpan2021
Summary: I went on one beautiful day to get on my laptop and go on aops... (skips the anecdote lets get straight to the point)
so yeah i checked my profile and to my horror i found that my ratings (you know, the numbers next to the ovr, a1, a2, all of that) ceased to exist. Tried reloading, it did not restore it.

Browser: Chrome (chromebook)

Reproduce: 100%
like did i miss something new that removed the ratings or smth
i didnt even go to settings and i didnt mess with anything as well
ive added a screenshot to show
3 replies
AbhayAttarde01
Yesterday at 8:16 PM
bpan2021
Yesterday at 8:55 PM
k Server Search Down?
sadas123   2
N Dec 2, 2024 by sadas123
When I wanted to search math count mock tests on the server Search it said it was down. Is this a problem or is it supposed to happen? He is a photo included below:
2 replies
sadas123
Dec 2, 2024
sadas123
Dec 2, 2024
Server Search Down?
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sadas123
1330 posts
#1 • 1 Y
Y by PikaPika999
When I wanted to search math count mock tests on the server Search it said it was down. Is this a problem or is it supposed to happen? He is a photo included below:
Attachments:
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ultimate_life_form
2642 posts
#2 • 1 Y
Y by PikaPika999
sadas123 wrote:
When I wanted to search math count mock tests on the server Search it said it was down. Is this a problem or is it supposed to happen? He is a photo included below:

This is common, just try again and wait a bit before pressing the search button.
Z Y
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sadas123
1330 posts
#3 • 1 Y
Y by PikaPika999
Okay thanks!
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