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k a April Highlights and 2025 AoPS Online Class Information
jlacosta   0
Apr 2, 2025
Spring is in full swing and summer is right around the corner, what are your plans? At AoPS Online our schedule has new classes starting now through July, so be sure to keep your skills sharp and be prepared for the Fall school year! Check out the schedule of upcoming classes below.

WOOT early bird pricing is in effect, don’t miss out! If you took MathWOOT Level 2 last year, no worries, it is all new problems this year! Our Worldwide Online Olympiad Training program is for high school level competitors. AoPS designed these courses to help our top students get the deep focus they need to succeed in their specific competition goals. Check out the details at this link for all our WOOT programs in math, computer science, chemistry, and physics.

Looking for summer camps in math and language arts? Be sure to check out the video-based summer camps offered at the Virtual Campus that are 2- to 4-weeks in duration. 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 events:
[list][*]April 3rd (Webinar), 4pm PT/7:00pm ET, Learning with AoPS: Perspectives from a Parent, Math Camp Instructor, and University Professor
[*]April 8th (Math Jam), 4:30pm PT/7:30pm ET, 2025 MATHCOUNTS State Discussion
April 9th (Webinar), 4:00pm PT/7:00pm ET, Learn about Video-based Summer Camps at the Virtual Campus
[*]April 10th (Math Jam), 4:30pm PT/7:30pm ET, 2025 MathILy and MathILy-Er Math Jam: Multibackwards Numbers
[*]April 22nd (Webinar), 4:00pm PT/7:00pm ET, Competitive Programming at AoPS (USACO).[/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
Apr 2, 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
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
Some Problems
hashbrown2009   0
10 minutes ago
1. If x squared minus (x squared times pi)/4 equals 3+ 3 root 3 -2pi, solve for x.
2. You're playing a game where you need to roll at least N to win. You can either roll 2 6-sided fair dice or a 12-sided fair die. For what value of n between 1 and 12, inclusive, is the probability of winning equal no matter which dice you choose?
3. Define the polynomial P(x)=(x^3)+1. Find the sum of the coefficients of P(P(P(x))).
4. Jerry chooses 2 positive integers x and y that yield a product of 6^5, or 7776. He then computes the value of n, which is the GCD of (a,b). How many possible values of n can Jerry get?

Provide solutions to answers


Also how hard are these problems: AMC8, AMC10, MathCounts, or AMC12?
0 replies
hashbrown2009
10 minutes ago
0 replies
FTW tournament!
evt917   343
N 14 minutes ago by sadas123
[center]Since all FTW tournaments have dramatically failed, I'm trying a different format. Here is how it works:

1. Type \signup{your rating (type 800 for unrated)}

2. You will pick who you want to play with. You can play if they accept your challenge. So basically the players run everything. Just don't intentionally play low-rated people. Also try to play different people so everyone gets a chance to play! ONLY two player games.

3. If you win, you get 2 points. Ties get one point, and losses get zero.

4. I do not know everybody's time preferences. Because so, I will announce in advance which two players will be playing, so they themselves can organize a game themselves. Remember, THE PLAYERS ARE ORGANIZING THE GAMES THEMSELVES!!! The format is up to them, but please make the time control at least 20 seconds. Please announce the results of the game here so i can update the scoreboard. Games can be unrated.

recommended format if you cannot decide



5. The tournament goes on until april 10th! Extremely long, right? Note that you can still signup after the first games has started, but you will have a disadvantage because some people who signed up as soon as the tournament started already has points.

6. Once you are done with your game, you can find a new opponent and play with them if they want. Note that you must play opponents within the tournament. If you play in the tournament, you are automatically signed up. Have fun!


[rule]

Questions and Answers

All signups and ratings

[rule]

LIVE LEADERBOARD:

1st place: 47 points | 17W 3L 3T | Yrock
2nd place: 14 points | 6W 3L 2T | jb2015007
3rd place: 5 points | 2W 8L 1T | sadas123

4th place: 4 points | 1W 2L 0T | IcyFire500
5th place: 0 points | 0W 1L 0T | NS0004
343 replies
evt917
Apr 3, 2025
sadas123
14 minutes ago
mathcounts state score thread
Soupboy0   75
N 18 minutes ago by iwastedmyusername
\begin{table}[]
\begin{tabular}{llllll}
Username & Score & Sprint & Target & Nats? & Sillies \\
     Soupboy0    &     40  &     24   &   16     &    yes  &    6     \\
         &       &        &        &       &         \\
         &       &        &        &       &        
\end{tabular}\end{table}
75 replies
+1 w
Soupboy0
Apr 1, 2025
iwastedmyusername
18 minutes ago
The daily problem!
Leeoz   65
N 44 minutes ago by HacheB2031
Every day, I will try to post a new problem for you all to solve! If you want to post a daily problem, you can! :)

Please hide solutions and answers, hints are fine though! :)

The first problem is:
[quote=March 21st Problem]Alice flips a fair coin until she gets 2 heads in a row, or a tail and then a head. What is the probability that she stopped after 2 heads in a row? Express your answer as a common fraction.[/quote]

Past Problems!
65 replies
Leeoz
Mar 21, 2025
HacheB2031
44 minutes ago
Two Functional Inequalities
Mathdreams   6
N an hour ago by Assassino9931
Source: 2025 Nepal Mock TST Day 2 Problem 2
Determine all functions $f : \mathbb{R} \rightarrow \mathbb{R}$ such that $$f(x) \le x^3$$and $$f(x + y) \le f(x) + f(y) + 3xy(x + y)$$for any real numbers $x$ and $y$.

(Miroslav Marinov, Bulgaria)
6 replies
Mathdreams
Today at 1:34 PM
Assassino9931
an hour ago
Pythagorean new journey
XAN4   2
N an hour ago by mathprodigy2011
Source: Inspired by sarjinius
The number $4$ is written on the blackboard. Every time, Carmela can erase the number $n$ on the black board and replace it with a new number $m$, if and only if $|n^2-m^2|$ is a perfect square. Prove or disprove that all positive integers $n\geq4$ can be written exactly once on the blackboard.
2 replies
XAN4
Today at 3:41 AM
mathprodigy2011
an hour ago
sqrt(2) and sqrt(3) differ in at least 1000 digits
Stuttgarden   2
N an hour ago by straight
Source: Spain MO 2025 P3
We write the decimal expressions of $\sqrt{2}$ and $\sqrt{3}$ as \[\sqrt{2}=1.a_1a_2a_3\dots\quad\quad\sqrt{3}=1.b_1b_2b_3\dots\]where each $a_i$ or $b_i$ is a digit between 0 and 9. Prove that there exist at least 1000 values of $i$ between $1$ and $10^{1000}$ such that $a_i\neq b_i$.
2 replies
Stuttgarden
Mar 31, 2025
straight
an hour ago
combinatorics and number theory beautiful problem
Medjl   2
N an hour ago by mathprodigy2011
Source: Netherlands TST for BxMo 2017 problem 4
A quadruple $(a; b; c; d)$ of positive integers with $a \leq b \leq c \leq d$ is called good if we can colour each integer red, blue, green or purple, in such a way that
$i$ of each $a$ consecutive integers at least one is coloured red;
$ii$ of each $b$ consecutive integers at least one is coloured blue;
$iii$ of each $c$ consecutive integers at least one is coloured green;
$iiii$ of each $d$ consecutive integers at least one is coloured purple.
Determine all good quadruples with $a = 2.$
2 replies
Medjl
Feb 1, 2018
mathprodigy2011
an hour ago
Squence problem
AlephG_64   1
N 2 hours ago by RagvaloD
Source: 2025 Finals Portuguese Math Olympiad P1
Francisco wrote a sequence of numbers starting with $25$. From the fourth term of the sequence onwards, each term of the sequence is the average of the previous three. Given that the first six terms of the sequence are natural numbers and that the sixth number written was $8$, what is the fifth term of the sequence?
1 reply
1 viewing
AlephG_64
Yesterday at 1:19 PM
RagvaloD
2 hours ago
50 points in plane
pohoatza   12
N 2 hours ago by de-Kirschbaum
Source: JBMO 2007, Bulgaria, problem 3
Given are $50$ points in the plane, no three of them belonging to a same line. Each of these points is colored using one of four given colors. Prove that there is a color and at least $130$ scalene triangles with vertices of that color.
12 replies
pohoatza
Jun 28, 2007
de-Kirschbaum
2 hours ago
beautiful functional equation problem
Medjl   6
N 2 hours ago by Sadigly
Source: Netherlands TST for BxMO 2017 problem 2
Let define a function $f: \mathbb{N} \rightarrow \mathbb{Z}$ such that :
$i)$$f(p)=1$ for all prime numbers $p$.
$ii)$$f(xy)=xf(y)+yf(x)$ for all positive integers $x,y$
find the smallest $n \geq 2016$ such that $f(n)=n$
6 replies
Medjl
Feb 1, 2018
Sadigly
2 hours ago
Line Combining Fermat Point, Orthocenter, and Centroid
cooljoseph   0
2 hours ago
On triangle $ABC$, draw exterior equilateral triangles on sides $AB$ and $AC$ to obtain $ABC'$ and $ACB'$, respectively. Let $X$ be the intersection of the altitude through $B$ and the median through $C$. Let $Y$ be the intersection of the altitude through $A$ and line $CC'$. Let $Z$ be the intersection of the median through $A$ and the line $BB'$. Prove that $X$, $Y$, and $Z$ lie on a common line.

IMAGE
0 replies
cooljoseph
2 hours ago
0 replies
complete integral values
Medjl   2
N 2 hours ago by Sadigly
Source: Netherlands TST for BxMO 2017 problem 1
Let $n$ be an even positive integer. A sequence of $n$ real numbers is called complete if for every integer $m$ with $1 \leq  m \leq  n$ either the sum of the first $m$ terms of the sum or the sum of the last $m$ terms is integral. Determine
the minimum number of integers in a complete sequence of $n$ numbers.
2 replies
Medjl
Feb 1, 2018
Sadigly
2 hours ago
interesting ineq
nikiiiita   5
N 2 hours ago by nikiiiita
Source: Own
Given $a,b,c$ are positive real numbers satisfied $a^3+b^3+c^3=3$. Prove that:
$$\sqrt{2ab+5c^{2}+2a}+\sqrt{2bc+5a^{2}+2b}+\sqrt{2ac+5b^{2}+2c}\le3\sqrt{3\left(a+b+c\right)}$$
5 replies
nikiiiita
Jan 29, 2025
nikiiiita
2 hours ago
9 MATHCOUNTS STATE difficulty
Eddie_tiger   67
N Apr 4, 2025 by DhruvJha
I personally thought the problems were much easier than last year, but I didn't really improve as much as I would of liked to improve.
67 replies
Eddie_tiger
Apr 1, 2025
DhruvJha
Apr 4, 2025
MATHCOUNTS STATE difficulty
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G H BBookmark kLocked kLocked NReply
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Eddie_tiger
336 posts
#1 • 1 Y
Y by PikaPika999
9Poll:
How was the difficulty of the problems compared to last year?
165 Votes
59%
(97)
25%
(41)
4%
(7)
5%
(9)
2%
(4)
4%
(7)
Hide Results Show Results
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I personally thought the problems were much easier than last year, but I didn't really improve as much as I would of liked to improve.
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StrawberriBunni
11 posts
#2
Y by
Yeah I sillied target 4 and I ran out of time for the last 3 on sprint, but it was a lot easier than last year.
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c_double_sharp
305 posts
#3
Y by
sprint: chapter difficulty
target: a bit easier but last year's was also extremely free
team even tho no one cares about team: average, maybe a bit hard
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Eddie_tiger
336 posts
#4
Y by
I sold on sprint (27-->22)
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DhruvJha
839 posts
#5
Y by
Arkansas is gonna be so good this year. Highest score in the nation along with the second highest score in the nation.
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orangebear
662 posts
#6
Y by
Easier than last Year tho I sillied 3 questions on the sprint and 1 on target :stink:
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Existing_Human1
231 posts
#7
Y by
Where can I find solutions and papers?
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DhruvJha
839 posts
#8
Y by
Existing_Human1 wrote:
Where can I find solutions and papers?

It'll come out soon enough
Z K Y
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Existing_Human1
231 posts
#9
Y by
Today? $             $
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DhruvJha
839 posts
#10
Y by
Existing_Human1 wrote:
Today? $             $

Yes
Z K Y
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Existing_Human1
231 posts
#11
Y by
What did you get for sprint #8
Z K Y
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hashbrown2009
158 posts
#12
Y by
My younger brother said the target round was insanely easy
sprint was moderate
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orangebear
662 posts
#13
Y by
There is a kid in my state (PA) who might make nationals who has autism (Has there ever been a kid with autism who made Nats?)
Z K Y
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Inaaya
222 posts
#14
Y by
idk i didn't even qual states last year
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Acumlus
9 posts
#15
Y by
orangebear wrote:
There is a kid in my state (PA) who might make nationals who has autism (Has there ever been a kid with autism who made Nats?)

I feel as this question is really offensive
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