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H
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
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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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All Topics Marked
alpha31415   6
N 20 minutes ago by Craftybutterfly
Excuse me!
for I am a frashman in aops.I wonder how I could get back to mark all my read.All topics in the forum became as if they had been marked.Would someone please help me deal with it???
6 replies
alpha31415
May 16, 2025
Craftybutterfly
20 minutes ago
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USAMO 2002 Problem 3
MithsApprentice   21
N an hour ago by bjump
Prove that any monic polynomial (a polynomial with leading coefficient 1) of degree $n$ with real coefficients is the average of two monic polynomials of degree $n$ with $n$ real roots.
21 replies
MithsApprentice
Sep 30, 2005
bjump
an hour ago
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Not injective? Not surjective?
BBNoDollar   2
N an hour ago by jasperE3
Let the function \( f : \mathbb{N} \to \mathbb{N} \) be defined by
\[ f(n) = \left\lfloor \frac{n}{3} \right\rfloor + \left\lfloor \frac{n+1}{5} \right\rfloor + \left\lfloor \frac{n+2}{7} \right\rfloor, \]for any \( n \in \mathbb{N} \).

Prove that the function \( f \) is neither injective nor surjective.
2 replies
BBNoDollar
an hour ago
jasperE3
an hour ago
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Inequality with x+y+z=1.
FrancoGiosefAG   0
an hour ago
Let $x,y,z$ be positive real numbers such that $x+y+z=1$. Show that
\[ \frac{x^2-yz}{x^2+x}+\frac{y^2-zx}{y^2+y}+\frac{z^2-xy}{z^2+z}\leq 0. \]
0 replies
FrancoGiosefAG
an hour ago
0 replies
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Tangencies with cyclic quadrilateral
tapir1729   20
N an hour ago by Rayvhs
Source: TSTST 2024, problem 4
Let $ABCD$ be a quadrilateral inscribed in a circle with center $O$ and $E$ be the intersection of segments $AC$ and $BD$. Let $\omega_1$ be the circumcircle of $ADE$ and $\omega_2$ be the circumcircle of $BCE$. The tangent to $\omega_1$ at $A$ and the tangent to $\omega_2$ at $C$ meet at $P$. The tangent to $\omega_1$ at $D$ and the tangent to $\omega_2$ at $B$ meet at $Q$. Show that $OP=OQ$.

Merlijn Staps
20 replies
tapir1729
Jun 24, 2024
Rayvhs
an hour ago
J
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Hard positive real FE
ZETA_in_olympiad   5
N 2 hours ago by jasperE3
Source: 2022 IMOC A6
Find all functions $f:\mathbb R^+\to \mathbb R^+$ such that $$f(x+y)f(f(x))=f(1+yf(x))$$for all $x,y\in \mathbb R^+.$

Proposed by Ming Hsiao

5 replies
ZETA_in_olympiad
Sep 5, 2022
jasperE3
2 hours ago
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Exsimilicenter of weird incircles
awesomeming327.   14
N 2 hours ago by MathSaiyan
Source: CMO 2025
Let $ABC$ be a triangle with circumcircle $\Gamma$ and $AB\neq AC$. Let $D$ and $E$ lie on the arc $BC$ of $\Gamma$ not containing $A$ such that $\angle BAE=\angle DAC$. Let the incenters of $BAE$ and $CAD$ be $X$ and $Y$, respectively, and let the external tangents of the incircles of $BAE$ and $CAD$ intersect at $Z$. Prove that $Z$ lies on the common chord of $\Gamma$ and the circumcircle of $AXY$.
14 replies
awesomeming327.
Mar 7, 2025
MathSaiyan
2 hours ago
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Functional Inequality Implies Uniform Sign
peace09   35
N 2 hours ago by EpicBird08
Source: 2023 ISL A2
Let $\mathbb{R}$ be the set of real numbers. Let $f:\mathbb{R}\rightarrow\mathbb{R}$ be a function such that \[f(x+y)f(x-y)\geqslant f(x)^2-f(y)^2\]for every $x,y\in\mathbb{R}$. Assume that the inequality is strict for some $x_0,y_0\in\mathbb{R}$.

Prove that either $f(x)\geqslant 0$ for every $x\in\mathbb{R}$ or $f(x)\leqslant 0$ for every $x\in\mathbb{R}$.
35 replies
peace09
Jul 17, 2024
EpicBird08
2 hours ago
J
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Introducing myself at AoPS, and what's your magic wand?
asuth_asuth   1249
N 3 hours ago by BlackShark28
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.
1249 replies
asuth_asuth
Mar 30, 2025
BlackShark28
3 hours ago
J
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Hard math inequality
noneofyou34   0
3 hours ago
Let a, b, c, d be nonnegative real numbers such that

3(a+b+c+d)=2(ab+ac+ad+bc+bd+cd)> 0.
Prove that:
8(a3+b3+c3+d3) + 49abcd ≥ 81.

0 replies
noneofyou34
3 hours ago
0 replies
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Inequality with ^3+b^3+c^3+3abc=6
bel.jad5   5
N 3 hours ago by ytChen
Source: Own
Let $a,b,c\geq 0$ and $a^3+b^3+c^3+3abc=6$. Prove that:
\[ \frac{a^2+1}{a+1}+\frac{b^2+1}{b+1}+\frac{c^2+1}{c+1} \geq 3\]
5 replies
bel.jad5
Sep 2, 2018
ytChen
3 hours ago
J
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Polynomial with roots a_i^3 differ by 3X
navi_09220114   1
N 3 hours ago by sami1618
Source: TASIMO 2025 Day 2 Problem 4
Show that there are no monic polynomials $P(X)$ with real coefficients of degree $n\geq 4$ such that the following two conditions hold:

i)They have only real roots denoted by $a_1,\cdots, a_n$ (they are not necessarily distinct);

ii) The roots of the polynomial $P(X)-3X$ are $a_1^3,\cdots, a_n^3$.

Note. A polynomial is called monic if the coefficient of its leading term, i.e., the term of the highest degree is one. For example, the polynomial $P(X)=X^{100}-10X+5$ is monic since the coefficient of $X^{100}$ is one.
1 reply
navi_09220114
Yesterday at 11:48 AM
sami1618
3 hours ago
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k alcumus going crazy?
LittleSnake____   61
N Yesterday at 4:40 PM by jlacosta
all of a sudden, the alcumus forum has gotten completely exploded by gamebot's posts.

https://artofproblemsolving.com/community/c63h3570498_alcumus_going_crazy
61 replies
LittleSnake____
May 18, 2025
jlacosta
Yesterday at 4:40 PM
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k New user not allowed to use LaTeX
Cats_on_a_computer   8
N Yesterday at 6:04 AM by Cats_on_a_computer
Do I seriously have to post everyday for 14 days for me not to be considered a “new user? I didn’t even upload any images, I just used LaTeX. How am I supposed to write anything without LaTeX?
8 replies
1 viewing
Cats_on_a_computer
May 18, 2025
Cats_on_a_computer
Yesterday at 6:04 AM
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J
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k Internet bug
MmathB   8
N Apr 24, 2025 by MathDolphin95
I am trying to post topics in a forum, but every time I try to post it asks me to check my internet even though the signal is strong can somebody tell me what's going on
8 replies
MmathB
Apr 23, 2025
MathDolphin95
Apr 24, 2025
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Internet bug
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Reveal topic tags
internet
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MmathB
856 posts
MmathB
#1 h  Apr 23, 2025, 5:41 PM
Y by
I am trying to post topics in a forum, but every time I try to post it asks me to check my internet even though the signal is strong can somebody tell me what's going on
Z Y
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PikachuSmile
74 posts
PikachuSmile
#2 h  Apr 23, 2025, 6:37 PM
Y by
Idk ?, I can’t reproduce. Maybe the browser is not supported?
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jlacosta
649 posts
jlacosta
#3 h  Apr 23, 2025, 8:35 PM
Y by
Can you provide a screenshot of what the error message says?
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jkim0656
1046 posts
jkim0656
#4 h  Apr 24, 2025, 12:44 AM
Y by
can not reproduce
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LawofCosine
836 posts
LawofCosine
#5 h  Apr 24, 2025, 5:53 AM
Y by
just refresh i think
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Craftybutterfly
534 posts
Craftybutterfly
#6 h  Apr 24, 2025, 7:36 PM
Y by
MmathB wrote:
I am trying to post topics in a forum, but every time I try to post it asks me to check my internet even though the signal is strong can somebody tell me what's going on

The same thing happened just now but it disappered after I connected to the same wifi again
Z Y
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MmathB
856 posts
MmathB
#7 h  Apr 24, 2025, 9:27 PM
Y by
its gone ty
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MmathB
856 posts
MmathB
#8 h  Apr 24, 2025, 9:28 PM
Y by
request lock
Z Y
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MathDolphin95
2447 posts
MathDolphin95
#9 h  Apr 24, 2025, 9:38 PM
Y by
MmathB wrote:
request lock

Just edit the title to say [RESOLVED].

Writing request lock in a post doesn't really do anything.
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