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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]
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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
J
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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
J
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Introducing a math summer program for middle school students
harry133   1
N an hour ago by heheman
Introducing IITSP, an online math summer program designed for middle school students over summer.

The program is designed by Professor Shubhrangshu Dasgupta from the Department of Physics at the Indian Institute of Technology Ropar (IIT Ropar).

Please check out the webpage if you are interested in.

https://www.imc-impea.org/IMC/bbs/content.php?co_id=iitsp
1 reply
harry133
Today at 12:52 AM
heheman
an hour ago
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Alcumus vs books
UnbeatableJJ   20
N an hour ago by SirAppel
If I am aiming for AIME, then JMO afterwards, is Alcumus adequate, or I still need to do the problems on AoPS books?

I got AMC 23 this year, and never took amc 10 before. If I master the alcumus of intermediate algebra (making all of the bars blue). How likely I can qualify for AIME 2026?
20 replies
1 viewing
UnbeatableJJ
Apr 23, 2025
SirAppel
an hour ago
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Can't be power of 2
shobber   31
N an hour ago by LeYohan
Source: APMO 1998
Show that for any positive integers $a$ and $b$, $(36a+b)(a+36b)$ cannot be a power of $2$.
31 replies
shobber
Mar 17, 2006
LeYohan
an hour ago
J
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LTE or Binomial Theorem
P_Groudon   111
N an hour ago by heheman
Source: 2020 AIME I #12
Let $n$ be the least positive integer for which $149^n - 2^n$ is divisible by $3^3 \cdot 5^5 \cdot 7^7$. Find the number of positive divisors of $n$.
111 replies
P_Groudon
Mar 12, 2020
heheman
an hour ago
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Bring Back Downvotes
heheman   5
N an hour ago by heheman
i would like to start a petition to bring back downvote, it you agree then write "bbd $ $" in threads
5 replies
heheman
2 hours ago
heheman
an hour ago
J
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Brilliant Problem
M11100111001Y1R   4
N an hour ago by IAmTheHazard
Source: Iran TST 2025 Test 3 Problem 3
Find all sequences \( (a_n) \) of natural numbers such that for every pair of natural numbers \( r \) and \( s \), the following inequality holds:
\[ \frac{1}{2} < \frac{\gcd(a_r, a_s)}{\gcd(r, s)} < 2 \]
4 replies
M11100111001Y1R
Yesterday at 7:28 AM
IAmTheHazard
an hour ago
J
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Own made functional equation
Primeniyazidayi   1
N 2 hours ago by Primeniyazidayi
Source: own(probably)
Find all functions $f:R \rightarrow R$ such that $xf(x^2+2f(y)-yf(x))=f(x)^3-f(y)(f(x^2)-2f(x))$ for all $x,y \in \mathbb{R}$
1 reply
Primeniyazidayi
May 26, 2025
Primeniyazidayi
2 hours ago
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not fun equation
DottedCaculator   13
N 2 hours ago by Adywastaken
Source: USA TST 2024/6
Find all functions $f\colon\mathbb R\to\mathbb R$ such that for all real numbers $x$ and $y$,
\[f(xf(y))+f(y)=f(x+y)+f(xy).\]
Milan Haiman
13 replies
DottedCaculator
Jan 15, 2024
Adywastaken
2 hours ago
J
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Serbian selection contest for the IMO 2025 - P6
OgnjenTesic   12
N 3 hours ago by atdaotlohbh
Source: Serbian selection contest for the IMO 2025
For an $n \times n$ table filled with natural numbers, we say it is a divisor table if:
- the numbers in the $i$-th row are exactly all the divisors of some natural number $r_i$,
- the numbers in the $j$-th column are exactly all the divisors of some natural number $c_j$,
- $r_i \ne r_j$ for every $i \ne j$.

A prime number $p$ is given. Determine the smallest natural number $n$, divisible by $p$, such that there exists an $n \times n$ divisor table, or prove that such $n$ does not exist.

Proposed by Pavle Martinović
12 replies
OgnjenTesic
May 22, 2025
atdaotlohbh
3 hours ago
J
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Geometry with fix circle
falantrng   33
N 3 hours ago by zuat.e
Source: RMM 2018 Problem 6
Fix a circle $\Gamma$, a line $\ell$ to tangent $\Gamma$, and another circle $\Omega$ disjoint from $\ell$ such that $\Gamma$ and $\Omega$ lie on opposite sides of $\ell$. The tangents to $\Gamma$ from a variable point $X$ on $\Omega$ meet $\ell$ at $Y$ and $Z$. Prove that, as $X$ varies over $\Omega$, the circumcircle of $XYZ$ is tangent to two fixed circles.
33 replies
falantrng
Feb 25, 2018
zuat.e
3 hours ago
J
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USAMO 2001 Problem 2
MithsApprentice   54
N 3 hours ago by lpieleanu
Let $ABC$ be a triangle and let $\omega$ be its incircle. Denote by $D_1$ and $E_1$ the points where $\omega$ is tangent to sides $BC$ and $AC$, respectively. Denote by $D_2$ and $E_2$ the points on sides $BC$ and $AC$, respectively, such that $CD_2=BD_1$ and $CE_2=AE_1$, and denote by $P$ the point of intersection of segments $AD_2$ and $BE_2$. Circle $\omega$ intersects segment $AD_2$ at two points, the closer of which to the vertex $A$ is denoted by $Q$. Prove that $AQ=D_2P$.
54 replies
MithsApprentice
Sep 30, 2005
lpieleanu
3 hours ago
J
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German-Style System of Equations
Primeniyazidayi   1
N 4 hours ago by Primeniyazidayi
Source: German MO 2025 11/12 Day 1 P1
Solve the system of equations in $\mathbb{R}$

\begin{align*} \frac{a}{c} &= b-\sqrt{b}+c \\ \sqrt{\frac{a}{c}} &= \sqrt{b}+1 \\ \sqrt[4]{\frac{a}{c}} &=\sqrt[3]{b}-1 \end{align*}
1 reply
Primeniyazidayi
4 hours ago
Primeniyazidayi
4 hours ago
J
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gcd nt from switzerland
AshAuktober   5
N 4 hours ago by Siddharthmaybe
Source: Swiss 2025 Second Round
Let $a, b$ be positive integers. Prove that the expression
\[\frac{\gcd(a+b,ab)}{\gcd(a,b)}\]is always a positive integer, and determine all possible values it can take.
5 replies
AshAuktober
5 hours ago
Siddharthmaybe
4 hours ago
J
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Shortlist 2017/G1
fastlikearabbit   92
N 4 hours ago by Ilikeminecraft
Source: Shortlist 2017
Let $ABCDE$ be a convex pentagon such that $AB=BC=CD$, $\angle{EAB}=\angle{BCD}$, and $\angle{EDC}=\angle{CBA}$. Prove that the perpendicular line from $E$ to $BC$ and the line segments $AC$ and $BD$ are concurrent.
92 replies
fastlikearabbit
Jul 10, 2018
Ilikeminecraft
4 hours ago
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Mathroots
Ruegerbyrd   10
N Apr 26, 2025 by nmlikesmath
Has anyone gotten acceptances from MIT's Mathroots yet? Did they ever say they wouldn't send letters to anyone unless accepted?
10 replies
Ruegerbyrd
Mar 22, 2025
nmlikesmath
Apr 26, 2025
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Mathroots
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Ruegerbyrd
1107 posts
Ruegerbyrd
#1 h  Mar 22, 2025, 4:33 AM • 1 Y
Y by Ruhanna
Has anyone gotten acceptances from MIT's Mathroots yet? Did they ever say they wouldn't send letters to anyone unless accepted?
This post has been edited 1 time. Last edited by Ruegerbyrd, Mar 22, 2025, 4:34 AM
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Turtle09
1817 posts
Turtle09
#3 h  Apr 25, 2025, 10:47 PM
Y by
Results are out, got mine this afternoon

rejected
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Aaron_Q
29 posts
Aaron_Q
#4 h  Apr 26, 2025, 2:07 AM
Y by
rejected too
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Ruegerbyrd
1107 posts
Ruegerbyrd
#5 h  Apr 26, 2025, 2:28 AM
Y by
rejected :D
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Panda729
271 posts
Panda729
#6 h  Apr 26, 2025, 2:55 AM
Y by
oof :maybe:
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nmlikesmath
523 posts
nmlikesmath
#7 h  Apr 26, 2025, 2:57 AM
Y by
bro these camps literally only want superheroes at this point bruh
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jkim0656
1070 posts
jkim0656
#8 h  Apr 26, 2025, 3:12 AM
Y by
nmlikesmath wrote:
bro these camps literally only want superheroes at this point bruh

so real
i mean like what is this acceptance rate so far
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nmlikesmath
523 posts
nmlikesmath
#9 h  Apr 26, 2025, 3:29 AM
Y by
i think its like a 4% just like harvard, but there are genuinely kids who raised millions of dollars and started nonprofits with stellar grades and they still got rejected from these places
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justJen
1957 posts
justJen
#10 h  Apr 26, 2025, 7:41 PM • 1 Y
Y by Ruhanna
nmlikesmath wrote:
bro these camps literally only want superheroes at this point bruh

untrue! i had a friend who went to mathroots who is a lovely person and is definitely incredibly cracked but probably not the insane-out-of-your-mind you're picturing; i think the essays really matter for mathroots.

btw they mostly accept rising seniors so younger people don't feel discouraged :)
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Turtle09
1817 posts
Turtle09
#11 h  Apr 26, 2025, 8:49 PM
Y by
justJen wrote:
nmlikesmath wrote:
bro these camps literally only want superheroes at this point bruh

untrue! i had a friend who went to mathroots who is a lovely person and is definitely incredibly cracked but probably not the insane-out-of-your-mind you're picturing; i think the essays really matter for mathroots.

btw they mostly accept rising seniors so younger people don't feel discouraged :)

yeah I asked an accepted person and that is what they told me as well, because it's hard to stand out as there is no problem set (you can include stats, but everyone has "good" stats)
This post has been edited 1 time. Last edited by Turtle09, Apr 26, 2025, 8:49 PM
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nmlikesmath
523 posts
nmlikesmath
#12 h  Apr 26, 2025, 9:03 PM
Y by
justJen wrote:
nmlikesmath wrote:
bro these camps literally only want superheroes at this point bruh

untrue! i had a friend who went to mathroots who is a lovely person and is definitely incredibly cracked but probably not the insane-out-of-your-mind you're picturing; i think the essays really matter for mathroots.

btw they mostly accept rising seniors so younger people don't feel discouraged :)

well that makes sense
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