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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 August Highlights and 2025 AoPS Online Class Information
jwelsh   0
Aug 1, 2025
CONGRATULATIONS to all the competitors at this year’s International Mathematical Olympiad (IMO)! The US Team took second place with 5 gold medals and 1 silver - we are proud to say that each member of the 2025 IMO team has participated in an AoPS WOOT (Worldwide Online Olympiad Training) class!

"As a parent, I'm deeply grateful to AoPS. Tiger has taken very few math courses outside of AoPS, except for a local Math Circle that doesn't focus on Olympiad math. AoPS has been one of the most important resources in his journey. Without AoPS, Tiger wouldn't be where he is today — especially considering he's grown up in a family with no STEM background at all."
— Doreen Dai, parent of IMO US Team Member Tiger Zhang

Interested to learn more about our WOOT programs? Check out the course page here or join a Free Scheduled Info Session. Early bird pricing ends August 19th!:
CodeWOOT Code Jam - Monday, August 11th
ChemWOOT Chemistry Jam - Wednesday, August 13th
PhysicsWOOT Physics Jam - Thursday, August 14th
MathWOOT Math Jam - Friday, August 15th

There is still time to enroll in our last wave of summer camps that start in August at the Virtual Campus, our video-based platform, for math and language arts! From Math Beasts Camp 6 (Prealgebra Prep) to AMC 10/12 Prep, you can find an informative 2-week camp before school starts. Plus, our math camps don’t have homework and cover cool enrichment topics like graph theory. Our language arts courses will build the foundation for next year’s challenges, such as Language Arts Triathlon for levels 5-6 and Academic Essay Writing for high school students.

Lastly, Fall is right around the corner! You can plan your Fall schedule now with classes at either AoPS Online, AoPS Academy Virtual Campus, or one of our AoPS Academies around the US. We’ve opened new Academy locations in San Mateo, CA, Pasadena, CA, Saratoga, CA, Johns Creek, GA, Northbrook, IL, and Upper West Side (NYC), New York.

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
Sunday, Aug 17 - Dec 14
Tuesday, Aug 26 - Dec 16
Friday, Sep 5 - Jan 16
Monday, Sep 8 - Jan 12
Tuesday, Sep 16 - Jan 20 (4:30 - 5:45 pm ET/1:30 - 2:45 pm PT)
Sunday, Sep 21 - Jan 25
Thursday, Sep 25 - Jan 29
Wednesday, Oct 22 - Feb 25
Tuesday, Nov 4 - Mar 10
Friday, Dec 12 - Apr 10

Prealgebra 2 Self-Paced

Prealgebra 2
Sunday, Aug 17 - Dec 14
Tuesday, Sep 9 - Jan 13
Thursday, Sep 25 - Jan 29
Sunday, Oct 19 - Feb 22
Monday, Oct 27 - Mar 2
Wednesday, Nov 12 - Mar 18

Introduction to Algebra A Self-Paced

Introduction to Algebra A
Sunday, Aug 17 - Dec 14
Wednesday, Aug 27 - Dec 17
Friday, Sep 5 - Jan 16
Thursday, Sep 11 - Jan 15
Sunday, Sep 28 - Feb 1
Monday, Oct 6 - Feb 9
Tuesday, Oct 21 - Feb 24
Sunday, Nov 9 - Mar 15
Friday, Dec 5 - Apr 3

Introduction to Counting & Probability Self-Paced

Introduction to Counting & Probability
Monday, Aug 11 - Nov 3
Wednesday, Sep 3 - Nov 19
Sunday, Sep 21 - Dec 14 (1:00 - 2:30 pm ET/10:00 - 11:30 am PT)
Friday, Oct 3 - Jan 16
Sunday, Oct 19 - Jan 25
Tuesday, Nov 4 - Feb 10
Sunday, Dec 7 - Mar 8

Introduction to Number Theory
Wednesday, Aug 13 - Oct 29
Friday, Sep 12 - Dec 12
Sunday, Oct 26 - Feb 1
Monday, Dec 1 - Mar 2

Introduction to Algebra B Self-Paced

Introduction to Algebra B
Thursday, Aug 7 - Nov 20
Monday, Aug 18 - Dec 15
Sunday, Sep 7 - Jan 11
Thursday, Sep 11 - Jan 15
Wednesday, Sep 24 - Jan 28
Sunday, Oct 26 - Mar 1
Tuesday, Nov 4 - Mar 10
Monday, Dec 1 - Mar 30

Introduction to Geometry
Wednesday, Aug 13 - Feb 11
Tuesday, Aug 26 - Feb 24
Sunday, Sep 7 - Mar 8
Thursday, Sep 11 - Mar 12
Wednesday, Sep 24 - Mar 25
Sunday, Oct 26 - Apr 26
Monday, Nov 3 - May 4
Friday, Dec 5 - May 29

Paradoxes and Infinity
Sat & Sun, Sep 13 - Sep 14 (1:00 - 4:00 PM PT/4:00 - 7:00 PM ET)

Intermediate: Grades 8-12

Intermediate Algebra
Friday, Aug 8 - Feb 20
Tuesday, Aug 26 - Feb 24
Sunday, Sep 28 - Mar 29
Wednesday, Oct 8 - Mar 8
Sunday, Nov 16 - May 17
Thursday, Dec 11 - Jun 4

Intermediate Counting & Probability
Sunday, Sep 28 - Feb 15
Tuesday, Nov 4 - Mar 24

Intermediate Number Theory
Wednesday, Sep 24 - Dec 17

Precalculus
Wednesday, Aug 6 - Jan 21
Tuesday, Sep 9 - Feb 24
Sunday, Sep 21 - Mar 8
Monday, Oct 20 - Apr 6
Sunday, Dec 14 - May 31

Advanced: Grades 9-12

Calculus
Sunday, Sep 7 - Mar 15
Wednesday, Sep 24 - Apr 1
Friday, Nov 14 - May 22

Contest Preparation: Grades 6-12

MATHCOUNTS/AMC 8 Basics
Sunday, Aug 17 - Nov 9
Wednesday, Sep 3 - Nov 19
Tuesday, Sep 16 - Dec 9
Sunday, Sep 21 - Dec 14 (1:00 - 2:30 pm ET/10:00 - 11:30 am PT)
Monday, Oct 6 - Jan 12
Thursday, Oct 16 - Jan 22
Tues, Thurs & Sun, Dec 9 - Jan 18 (meets three times a week!)

MATHCOUNTS/AMC 8 Advanced
Sunday, Aug 17 - Nov 9
Tuesday, Aug 26 - Nov 11
Thursday, Sep 4 - Nov 20
Friday, Sep 12 - Dec 12
Monday, Sep 15 - Dec 8
Sunday, Oct 5 - Jan 11
Tues, Thurs & Sun, Dec 2 - Jan 11 (meets three times a week!)
Mon, Wed & Fri, Dec 8 - Jan 16 (meets three times a week!)

AMC 10 Problem Series
Sunday, Aug 10 - Nov 2
Thursday, Aug 14 - Oct 30
Tuesday, Aug 19 - Nov 4
Mon & Wed, Sep 15 - Oct 22 (meets twice a week!)
Mon, Wed & Fri, Oct 6 - Nov 3 (meets three times a week!)
Tue, Thurs & Sun, Oct 7 - Nov 2 (meets three times a week!)

AMC 10 Final Fives
Friday, Aug 15 - Sep 12
Sunday, Sep 7 - Sep 28
Tuesday, Sep 9 - Sep 30
Monday, Sep 22 - Oct 13
Sunday, Sep 28 - Oct 19 (1:00 - 2:30 pm ET/10:00 - 11:30 am PT)
Wednesday, Oct 8 - Oct 29
Thursday, Oct 9 - Oct 30

AMC 12 Problem Series
Wednesday, Aug 6 - Oct 22
Sunday, Aug 10 - Nov 2
Monday, Aug 18 - Nov 10
Mon & Wed, Sep 15 - Oct 22 (meets twice a week!)
Tues, Thurs & Sun, Oct 7 - Nov 2 (meets three times a week!)

AMC 12 Final Fives
Thursday, Sep 4 - Sep 25
Sunday, Sep 28 - Oct 19
Tuesday, Oct 7 - Oct 28

AIME Problem Series A
Thursday, Oct 23 - Jan 29

AIME Problem Series B
Tuesday, Sep 2 - Nov 18

F=ma Problem Series
Tuesday, Sep 16 - Dec 9
Friday, Oct 17 - Jan 30

WOOT Programs
Visit the pages linked for full schedule details for each of these programs!


MathWOOT Level 1
MathWOOT Level 2
ChemWOOT
CodeWOOT
PhysicsWOOT


Programming

Introduction to Programming with Python
Thursday, Aug 14 - Oct 30
Sunday, Sep 7 - Nov 23
Tuesday, Dec 2 - Mar 3

Intermediate Programming with Python
Friday, Oct 3 - Jan 16

USACO Bronze Problem Series
Wednesday, Sep 3 - Dec 3
Thursday, Oct 30 - Feb 5
Tuesday, Dec 2 - Mar 3

Physics

Introduction to Physics
Tuesday, Sep 2 - Nov 18
Sunday, Oct 5 - Jan 11
Wednesday, Dec 10 - Mar 11

Physics 1: Mechanics
Sunday, Sep 21 - Mar 22
Sunday, Oct 26 - Apr 26
0 replies
jwelsh
Aug 1, 2025
0 replies
ALCUMUS BUG
tintin21   7
N 3 hours ago by ahxun2006
What's going on here?
7 replies
tintin21
Jun 2, 2025
ahxun2006
3 hours ago
Commutative semigroup
SUN8691   7
N Yesterday at 10:46 PM by Etkan
Let (S, . ) a multiplicative semigroup .If for every x, y from S we have x^3= x and (x^2 )(y^2) =(y^2)(x^2) , then prove that S is commutative .
7 replies
SUN8691
Dec 7, 2022
Etkan
Yesterday at 10:46 PM
IMC 2009 Day 2 P2
joybangla   8
N Yesterday at 5:31 PM by Levieee
Suppose $f:\mathbb{R}\to \mathbb{R}$ is a two times differentiable function satisfying $f(0)=1,f^{\prime}(0)=0$ and for all $x\in [0,\infty)$, it satisfies
\[ f^{\prime \prime}(x)-5f^{\prime}(x)+6f(x)\ge 0 \]
Prove that, for all $x\in [0,\infty)$,
\[ f(x)\ge 3e^{2x}-2e^{3x} \]
8 replies
joybangla
Jul 16, 2014
Levieee
Yesterday at 5:31 PM
My TeXeR Is Not Saving, or Rendering.
AlienGirl05   7
N Yesterday at 4:43 PM by AlienGirl05
Greetings, Site Support,

I've been working on a TeXeR file. However, all of a sudden, it stopped saving my work, or rendering it. No matter how many times I pressed the save button, I wasn't being notified of my work being saved. Upon reloading the page, it wouldn't render my work (don't worry, I didn't actually lose any of my work; I have it saved in a backup Google Document). The "Render With BBCode" button isn't working either.

Thank you. :)
7 replies
AlienGirl05
Jul 28, 2025
AlienGirl05
Yesterday at 4:43 PM
Twice continuously differntiable function
enter16180   6
N Yesterday at 2:13 PM by Dragon2311
Source: IMC 2025, Problem 2
Let $f: \mathbb{R} \rightarrow \mathbb{R}$ be a twice continuously differentiable function, and suppose that $\int_{-1}^1 f(x) \mathrm{d} x=0$ and $f(1)=f(-1)=1$. Prove that
$$
\int_{-1}^1\left(f^{\prime \prime}(x)\right)^2 \mathrm{~d} x \geq 15
$$and find all such functions for which equality holds.
6 replies
enter16180
Jul 30, 2025
Dragon2311
Yesterday at 2:13 PM
An integral inequality
Anabcde   1
N Yesterday at 2:11 PM by Hello_Kitty
A function $f$ is continuous on [0, 1] and diffrentiable on (0, 1). Given that $f(0)=0$ and $0 \le f'(x) \le 1, \forall 0 \le x \le 1$. Prove:
$$(\int_{0}^{1} f(x) \,dx )^2 \ge  \int_{0}^{1} (f(x))^3 \,dx $$
1 reply
Anabcde
Yesterday at 1:05 PM
Hello_Kitty
Yesterday at 2:11 PM
prove that there exists \xi
Peter   22
N Yesterday at 9:13 AM by Mathloops
Source: IMC 1998 day 1 problem 4
The function $f: \mathbb{R}\rightarrow\mathbb{R}$ is twice differentiable and satisfies $f(0)=2,f'(0)=-2,f(1)=1$.
Prove that there is a $\xi \in ]0,1[$ for which we have $f(\xi)\cdot f'(\xi)+f''(\xi)=0$.
22 replies
Peter
Nov 1, 2005
Mathloops
Yesterday at 9:13 AM
Identity
Saucepan_man02   4
N Yesterday at 8:25 AM by ray66
Could anyone provide an elegant proof for this identity?

$\sum_{k=0}^{n} (-1)^k \binom{2n+1}{k} = (-1)^n \binom{2n}{n}$
4 replies
Saucepan_man02
Aug 1, 2025
ray66
Yesterday at 8:25 AM
operator integral analysis
Hello_Kitty   1
N Yesterday at 8:21 AM by alexheinis
Let $ n\in\mathbb{N^*} $ and an operator defined as $ \varphi(f)=\int_0^1f.\int_0^1\frac 1f $
for any continuous $ f>0 $.
- Find all $ f $ such $ \varphi(f)=\varphi(f^{2^n}) $
- What if $n<0$ now ?
1 reply
Hello_Kitty
Saturday at 10:59 PM
alexheinis
Yesterday at 8:21 AM
Limit of expression
enter16180   8
N Yesterday at 5:13 AM by YaoAOPS
Source: IMC 2025, Problem 10
For any positive integer $N$, let $S_N$ be the number of pairs of integers $1 \leq a, b \leq N$ such that the number $\left(a^2+a\right)\left(b^2+b\right)$ is a perfect square. Prove that the limit
$$
\lim _{N \rightarrow \infty} \frac{S_N}{N}
$$exists and find its value.
8 replies
enter16180
Jul 31, 2025
YaoAOPS
Yesterday at 5:13 AM
Maintenance
shaayonsamanta   5
N Yesterday at 2:36 AM by Yrock
Is AoPS on maintenance right now?

AoPS keeps telling me that there's an "error with connecting to the server" and that they'll "try again in ten seconds."

Also, sometimes when I refresh, AoPS refuses to load. I have to wait a couple of seconds before re-refreshing and getting the actual website.
5 replies
shaayonsamanta
Yesterday at 1:58 AM
Yrock
Yesterday at 2:36 AM
funny thread glitch
SpeedCuber7   6
N Yesterday at 1:18 AM by SpeedCuber7
i clicked on this thread in c&p but it transported me to hsm
apparently the thread got moved as i clicked on it

now it looks weird and it even worked after i clicked off
6 replies
SpeedCuber7
Saturday at 7:57 PM
SpeedCuber7
Yesterday at 1:18 AM
expected value of maximum of random process
enter16180   4
N Yesterday at 12:01 AM by Agsh2005
Source: IMC 2025, Problem 9
Let $n$ be a positive integer. Consider the following random process which produces $n$ sequence of $n$ distinct positive integers $X_1, X_2 \ldots, X_n$.
First, $X_1$ is chosen randomly with $\mathbb{P}\left(X_1=i\right)=2^{-i}$ for every positive integer $i$. For $1 \leq j \leq n-1$. having chosen $X_1, \ldots, X_j$, arrange the remaining positive integers in increasing order as $n_1<n_2<$ $\cdots$, and choose $X_{j+1}$ randomly with $\mathbb{P}\left(X_{j+1}=n_i\right)=2^{-i}$ for every positive integer $i$.
Let $Y_n=\max \left\{X_1, \ldots, X_n\right\}$. Show that
$$
\mathbb{E}\left[Y_n\right]=\sum_{i=1}^n \frac{2^i}{2^i-1}
$$where $\mathbb{E}\left[Y_n\right]$ is the expected value of $Y_n$.
4 replies
enter16180
Jul 31, 2025
Agsh2005
Yesterday at 12:01 AM
Fourier Series
EthanWYX2009   0
Saturday at 11:35 PM
Source: 2025 Spring NSTE(2)-3
Let \( x_1, x_2, \cdots, x_n \) be real numbers. Define \(\|x\| = \min_{n \in \mathbb{Z}} |x - n|\). Prove that:
\[
\sum_{1 \leq i, j \leq n} 2^{\|x_i - x_j\|} \leq \sum_{1 \leq i, j \leq n} 2^{\|x_i - x_j + \frac{1}{2}\|}.
\]Proposed by Site Mu
0 replies
EthanWYX2009
Saturday at 11:35 PM
0 replies
k AoPS Wiki unnaturally slow
weihou0   4
N Jun 2, 2025 by FunnyKoala17
Recently, I have noticed that the AoPS Wiki takes rather long to load. Normally, this would not be an issue, as some webpages are just a little sluggish on the server side. However, I recall the Wiki being no slower than any other page(forums, profile, etc.) when loading. Now, however, any Wiki page(problem archives, LaTeX tutorials, etc.) takes about 15 seconds to load compared to the regular site, which almost always loads instantly. I have attempted accessing the Wiki page using multiple different browsers such as Chrome and Safari, and have also tried switching operating systems and computers to no avail. Not an internet issue, either, as other sites load fine. Not sure if this is an issue other people experience? It seems as if the load times have changed in the last few months. I can recall when the Wiki loaded instantly just like the rest of the site.
4 replies
weihou0
May 31, 2025
FunnyKoala17
Jun 2, 2025
AoPS Wiki unnaturally slow
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weihou0
38 posts
#1 • 1 Y
Y by GA34-261
Recently, I have noticed that the AoPS Wiki takes rather long to load. Normally, this would not be an issue, as some webpages are just a little sluggish on the server side. However, I recall the Wiki being no slower than any other page(forums, profile, etc.) when loading. Now, however, any Wiki page(problem archives, LaTeX tutorials, etc.) takes about 15 seconds to load compared to the regular site, which almost always loads instantly. I have attempted accessing the Wiki page using multiple different browsers such as Chrome and Safari, and have also tried switching operating systems and computers to no avail. Not an internet issue, either, as other sites load fine. Not sure if this is an issue other people experience? It seems as if the load times have changed in the last few months. I can recall when the Wiki loaded instantly just like the rest of the site.
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tyang2031
436 posts
#2 • 1 Y
Y by GA34-261
idk abt this, but it may be ur issue
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IvoryFox96
838 posts
#3 • 2 Y
Y by miles888, GA34-261
It's not just you. I haven't really accessed the AoPS Wiki, but I just tried it, and it is slow. Here's how long it takes me to load it:
warning it will take you a long time to scroll
Call da IT dude
This post has been edited 2 times. Last edited by IvoryFox96, May 31, 2025, 11:22 PM
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Yiyj
434 posts
#4 • 1 Y
Y by GA34-261
its been slow since like two weeks ago, and it has never been fixed
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FunnyKoala17
351 posts
#5 • 1 Y
Y by GA34-261
Yiyj wrote:
its been slow since like two weeks ago, and it has never been fixed

It's common. Why I quit my alcumus grind, it loads too slow. Also, It has been happening since 5 months ago.
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