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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.

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0 replies
jlacosta
May 1, 2025
0 replies
Linear algebra
Feynmann123   5
N an hour ago by Feynmann123
Hi everyone,

I was wondering whether when I tried to compute e^(2x2 matrix) and got the expansions of sinx and cosx with the method of discounting the constant junk whether it plays any significance. I am a UK student and none of this is in my School syllabus so I was just wondering…


5 replies
Feynmann123
Yesterday at 6:44 PM
Feynmann123
an hour ago
[PMO20 Qualis] I. 15
Shinfu   0
2 hours ago
Suppose that ${a_n}$ is a nonconstant arithmetic sequence such that $a_1 = 1$ and the terms $a_3, a_{15}, a_{24}$ form a geometric sequence in that order. Find the smallest index $n$ for which $a_n < 0$.
$\text{(a) } 50 \qquad\text{(b) } 51 \qquad\text{(c) } 52 \qquad\text{(d) } 53$

Answer confirmation
0 replies
Shinfu
2 hours ago
0 replies
Minimize
lgx57   6
N 3 hours ago by lgx57
Minimize $\sqrt{\cos^2 x+(2-\sin x)^2}+\dfrac{1}{2}\sqrt{(\sqrt 3-\cos x)^2+(\sin x+1)^2}$
6 replies
lgx57
Friday at 1:29 PM
lgx57
3 hours ago
Inequalities
sqing   0
3 hours ago
Let $ a,b> 0 , \frac{a}{b^2}+\frac{b}{a^2}+\frac{56}{(a+b)^2} \leq 16.$ Prove that
$$ab(a+b) \geq 2$$Let $ a,b> 0 ,\frac{1}{a^2}+\frac{1}{b^2}+\frac{28}{(a+b)^2} \leq 9.$ Prove that
$$ab(a+b) \geq 2$$
0 replies
sqing
3 hours ago
0 replies
Request for the access of private marathons
Vulch   2
N 4 hours ago by Dragon_Yang
To all AoPS users and admin,
Sometimes I came across the marathon(i .e number theory marathon, functional equation marathon etc) which allow access only after submitting log in request.There is no other way to access the question related to that marathons.It would be glad to open all private marathons publicly.Thank you!
2 replies
Vulch
5 hours ago
Dragon_Yang
4 hours ago
[Mathira 2018 T7-C2] Inverse of exponential spam
aops-g5-gethsemanea2   1
N 4 hours ago by aops-g5-gethsemanea2
Find the inverse of the function $f(x)=\dfrac12\left(\dfrac{2^{-x}+2^x}{2^{-x}-2^x}+\dfrac{2^{-x}-2^x}{2^{-x}+2^x}\right)$.
1 reply
aops-g5-gethsemanea2
4 hours ago
aops-g5-gethsemanea2
4 hours ago
Inequalities
toanrathay   1
N 4 hours ago by sqing
Let $a,b,c$ be positive reals such that $1/a+1/b+1/c-9/4abc=3/4$, find $\min$ of $P=a^2+b^2+c^2$.
1 reply
toanrathay
4 hours ago
sqing
4 hours ago
[Sipnayan SHS] Written Round, Average, #4.6
LilKirb   5
N 4 hours ago by LilKirb
Define the function
\[f(n) = \sum_{k=0}^{n} \binom{n}{k} a_k, \quad n = 1, 2, 3, \ldots\]where
\[a_k = 
    \begin{cases}
        3^k, & \text{if } k \text{ is even}, \\
        0, & \text{if } k \text{ is odd}.
        \end{cases}
\]Find the remainder when \( f(10^9 + 2) \) is divided by \( 2^{20} + 1 \)
5 replies
LilKirb
Yesterday at 2:25 PM
LilKirb
4 hours ago
La hire's with only euclidian
Kscv   0
5 hours ago
How can I prove la hire's theorem with pure Euclidean geometry? Every single proof I see on the internet uses projective geometry which I have no idea of.

Can someone help me? I only need the proof for circles BTW.
0 replies
1 viewing
Kscv
5 hours ago
0 replies
Penchick Manga Club
LilKirb   1
N 5 hours ago by LilKirb
From $96$ distinct penguin chicks, $47$ are selected to form the Penchick Manga Club. Then, one of these $47$ members is assigned to be club president. Let $x$ be the number of ways to select the club and assign its president. Compute $x \pmod{97}.$

1 reply
LilKirb
5 hours ago
LilKirb
5 hours ago
Asymmetric Inequality in the Reals
MrHeccMcHecc   1
N 6 hours ago by sqing
Let $a,b,c$ be real numbers such that $\frac{1}{abc}+\frac 1a + \frac 1c = \frac 1b$. Given the maximum value of $$\frac{4}{a^2+1}+\frac{4}{b^2+1}+\frac{7}{c^2+1}$$is $\frac{p}{q}$ where $p,q$ are relatively prime positive integers, find $p+q$.
1 reply
MrHeccMcHecc
Today at 4:46 AM
sqing
6 hours ago
Who is Halp! ? (resolvedd)
A7456321   4
N Today at 2:53 AM by A7456321
Is Halp! a bot? This user has been posting questions in nearly all of my AoPS classes when the user isn't a part of the class, and this user has 150k posts.
4 replies
A7456321
Yesterday at 9:22 PM
A7456321
Today at 2:53 AM
How to create a poll?
whwlqkd   23
N Today at 2:18 AM by Craftybutterfly
How to create a poll in aops?
23 replies
whwlqkd
Yesterday at 12:24 PM
Craftybutterfly
Today at 2:18 AM
Stamina XP decreasing?
Craftybutterfly   18
N Today at 2:02 AM by Craftybutterfly
Summary of the problem: Last night when I checked, alcumus said I had 4250 stamina XP which is more than other people. However, when I just checked, it said I only earned 3905 XP. What is wrong?
Page URL: Hall of Fame
Steps to reproduce:
1. Go to hall of fame
2. Scroll to stamina XP earned
Expected behavior: It should still say I earned 4250 XP
Frequency: 100%
Operating system(s): HP Elitebook
Browser(s), including version: Chrome
IMAGE
18 replies
Craftybutterfly
May 22, 2025
Craftybutterfly
Today at 2:02 AM
Cannot post PHP
char0221   4
N May 2, 2025 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
May 2, 2025
Cannot post PHP
G H J
G H BBookmark kLocked kLocked NReply
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char0221
145 posts
#1
Y by
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
Attachments:
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Demetri
1405 posts
#2
Y by
Whoops I messed up trying to show an example and crashed a page :(
I have noticed this as well,
Try to post
systeem.initialize_user(username)
without the double e :)

@3below he's just active
This post has been edited 1 time. Last edited by Demetri, May 2, 2025, 12:02 PM
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bpan2021
2669 posts
#3 • 1 Y
Y by Demetri
I believe it is because it is a safety mechanism by the servers running the site to prevent any malicious behavior. Just a hunch, though.
Z K Y
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Mango247
1000041 posts
#4 • 4 Y
Y by Mycatisleo, Demetri, ShrewdBunny, AlienGirl05
Just tried it
It thinks you are trying to do a cross site scripting attack so cloudfare blocks you
Z K Y
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k1glaucus
691 posts
#8
Y by
Post #5

I believe site admins do not appear on the member list.
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