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k a March Highlights and 2025 AoPS Online Class Information
jlacosta   0
Mar 2, 2025
March is the month for State MATHCOUNTS competitions! Kudos to everyone who participated in their local chapter competitions and best of luck to all going to State! Join us on March 11th for a Math Jam devoted to our favorite Chapter competition problems! Are you interested in training for MATHCOUNTS? Be sure to check out our AMC 8/MATHCOUNTS Basics and Advanced courses.

Are you ready to level up with Olympiad training? Registration is open with early bird pricing available for our WOOT programs: MathWOOT (Levels 1 and 2), CodeWOOT, PhysicsWOOT, and ChemWOOT. What is WOOT? WOOT stands for Worldwide Online Olympiad Training and is a 7-month high school math Olympiad preparation and testing program that brings together many of the best students from around the world to learn Olympiad problem solving skills. Classes begin in September!

Do you have plans this summer? There are so many options to fit your schedule and goals whether attending a summer camp or taking online classes, it can be a great break from the routine of the school year. Check out our summer courses at AoPS Online, or if you want a math or language arts class that doesn’t have homework, but is an enriching summer experience, our AoPS Virtual Campus summer camps may be just the ticket! We are expanding our locations for our AoPS Academies across the country with 15 locations so far and new campuses opening in Saratoga CA, Johns Creek GA, and the Upper West Side NY. Check out this page for summer camp information.

Be sure to mark your calendars for the following events:
[list][*]March 5th (Wednesday), 4:30pm PT/7:30pm ET, HCSSiM Math Jam 2025. Amber Verser, Assistant Director of the Hampshire College Summer Studies in Mathematics, will host an information session about HCSSiM, a summer program for high school students.
[*]March 6th (Thursday), 4:00pm PT/7:00pm ET, Free Webinar on Math Competitions from elementary through high school. Join us for an enlightening session that demystifies the world of math competitions and helps you make informed decisions about your contest journey.
[*]March 11th (Tuesday), 4:30pm PT/7:30pm ET, 2025 MATHCOUNTS Chapter Discussion MATH JAM. AoPS instructors will discuss some of their favorite problems from the MATHCOUNTS Chapter Competition. All are welcome!
[*]March 13th (Thursday), 4:00pm PT/7:00pm ET, Free Webinar about Summer Camps at the Virtual Campus. Transform your summer into an unforgettable learning adventure! From elementary through high school, we offer dynamic summer camps featuring topics in mathematics, language arts, and competition preparation - all designed to fit your schedule and ignite your passion for learning.[/list]
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0 replies
jlacosta
Mar 2, 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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Burnout?
xHypotenuse   14
N an hour ago by JoyfulBear91
Hello everyone, these days I have a burning urge to pick up new math concepts because I think they are important/interesting. But I also feel a constant burnout where I get really tired when I try to solve math problems of these new concepts. I can't and then it gets very demotivating. I don't want to take a break from math because solving problems have become such a natural part of me and also I really want to qualify for usamo next year (my last year I can since it's senior yr). Any suggestions?
14 replies
xHypotenuse
Tuesday at 7:32 PM
JoyfulBear91
an hour ago
J
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Interesting inequality
sqing   0
2 hours ago
Source: Own
Let $ a,b\geq 0 . $ Prove that
$$ a^4+b^4 +kab\geq\left(\sqrt{k(k+2)}-1\right)ab(a+b+k)$$Where $ k>0 . $
$$ a^4+b^4 +ab\geq (\sqrt 3-1)ab(a+b+1)$$$$ a^4+b^4 +2ab\geq 2(\sqrt 2-1)ab(a+b+2)$$
0 replies
1 viewing
sqing
2 hours ago
0 replies
J
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Scribable Pairs
tastymath75025   5
N 2 hours ago by quantam13
Source: 2017 ELMO Shortlist G3
Call the ordered pair of distinct circles $(\omega, \gamma)$ scribable if there exists a triangle with circumcircle $\omega$ and incircle $\gamma$. Prove that among $n$ distinct circles there are at most $(n/2)^2$ scribable pairs.

Proposed by Daniel Liu
5 replies
tastymath75025
Jul 3, 2017
quantam13
2 hours ago
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Day Before Tips
elasticwealth   55
N 2 hours ago by JoyfulBear91
Hi Everyone,

USA(J)MO is tomorrow. I am a Junior, so this is my last chance. I made USAMO by ZERO points but I've actually been studying oly seriously since JMO last year. I am more stressed than I was before AMC/AIME because I feel Olympiad is more unpredictable and harder to prepare for. I am fairly confident in my ability to solve 1/4 but whether I can solve the rest really leans on the topic distribution.

Anyway, I'm just super stressed and not sure what to do. All tips are welcome!

Thanks everyone! Good luck tomorrow!
55 replies
elasticwealth
Yesterday at 12:09 AM
JoyfulBear91
2 hours ago
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Hard complex numbers
RenheMiResembleRice   3
N 2 hours ago by aidan0626
Source: Wenxing Pan, Mingyu Jiang
Show that any non-zero complex number can be written as the sum of two complex numbers a + b such that a − b and a / b are purely imaginary.
3 replies
RenheMiResembleRice
3 hours ago
aidan0626
2 hours ago
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primitive polyominoes
N.T.TUAN   28
N 2 hours ago by quantam13
Source: USAMO 2007
An animal with $n$ cells is a connected figure consisting of $n$ equal-sized cells[1].

A dinosaur is an animal with at least $2007$ cells. It is said to be primitive it its cells cannot be partitioned into two or more dinosaurs. Find with proof the maximum number of cells in a primitive dinosaur.

(1) Animals are also called polyominoes. They can be defined inductively. Two cells are adjacent if they share a complete edge. A single cell is an animal, and given an animal with $n$ cells, one with $n+1$ cells is obtained by adjoining a new cell by making it adjacent to one or more existing cells.
28 replies
2 viewing
N.T.TUAN
Apr 26, 2007
quantam13
2 hours ago
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Inspired by Izho 2025
sqing   10
N 2 hours ago by sqing
Source: Own
Let $ a,b\geq 0 $ and $ (a - b)^2 + a + b \leq 2.$ Prove that
$$ 1 \geq a^3 + b^3 - ab\geq -\frac{1}{27}$$
10 replies
sqing
3 hours ago
sqing
2 hours ago
J
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9 What motivates you
AndrewZhong2012   69
N 2 hours ago by FunBrightStage
What got you guys into math? I'm asking because I got ~71 on the AMC 12B and 94.5 on 10A last year. This year, my dad expects me to get a 130 on 12B and 10 on AIME, but I have sort of lost motivation, and I know these goals will be impossible to achieve without said motivation.
69 replies
AndrewZhong2012
Feb 22, 2025
FunBrightStage
2 hours ago
J
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2 var inquality
Iveela   18
N 3 hours ago by sqing
Source: Izho 2025 P1
Let $a, b$ be positive reals such that $a^3 + b^3 = ab + 1$. Prove that \[(a-b)^2 + a + b \geq 2\]
18 replies
Iveela
Jan 14, 2025
sqing
3 hours ago
J
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Inequality
JK1603JK   0
3 hours ago
Source: unknown
Let a,b,c>=0 and ab+bc+ca>0 then prove \sqrt{a+b}+\sqrt{c+b}+\sqrt{a+c}\ge 2\sqrt[4]{ab+bc+ca}+\sqrt{\frac{a(b-c)^2+b(c-a)^2+c(a-b)^2}{ab+bc+ca}}
0 replies
1 viewing
JK1603JK
3 hours ago
0 replies
J
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USA(J)MO Discussion when?
sixoneeight   5
N 3 hours ago by Pengu14
when can we discuss the 2025 usa(j)mo/post the problems?
5 replies
1 viewing
sixoneeight
Yesterday at 10:37 PM
Pengu14
3 hours ago
J
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Interesting inequality
sqing   5
N 4 hours ago by sqing
Source: Own
Let $ a,b,c\geq 2 . $ Prove that
$$(a^2-1)(b-1)(c^2-1) -\frac{9}{4}abc\geq -9$$$$(a^2-1)(b-1)(c^2-1) -\frac{11}{5}abc\geq -\frac{43}{5}$$$$(a^2-1)(b-1)(c^2-1) -2abc\geq -7$$$$(a-1)(b^2-1)(c-1) -\frac{3}{4}abc\geq -3$$$$(a-1)(b^2-1)(c-1) -\frac{3}{5}abc\geq -\frac{9}{5}$$$$(a-1)(b^2-1)(c-1) -\frac{1}{2}abc\geq -1$$
5 replies
sqing
Yesterday at 12:49 PM
sqing
4 hours ago
J
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A polynomial problem
hef4875   4
N 4 hours ago by asdf334
Let $P(x)$ be a polynomial with real coefficients such that all its roots are real and nonzero. Prove that there are no 2 consecutive coefficients both zeros.
4 replies
1 viewing
hef4875
Jan 24, 2025
asdf334
4 hours ago
J
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Cool Number Theory
Fermat_Fanatic108   9
N 4 hours ago by Fermat_Fanatic108
For an integer with 5 digits $n=abcde$ (where $a, b, c, d, e$ are the digits and $a\neq 0$) we define the \textit{permutation sum} as the value $$bcdea+cdeab+deabc+eabcd$$For example the permutation sum of 20253 is $$02532+25320+53202+32025=113079$$Let $m$ and $n$ be two fivedigit integers with the same permutation sum.
Prove that $m=n$.
9 replies
1 viewing
Fermat_Fanatic108
Yesterday at 1:41 PM
Fermat_Fanatic108
4 hours ago
J
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J
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hcssim application question
enya_yurself   4
N Yesterday at 7:54 PM by akliu
do they send the Interesting Test to everyone who applied or do they read the friendly letter first and only send to the kids they like?
4 replies
enya_yurself
Mar 17, 2025
akliu
Yesterday at 7:54 PM
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hcssim application question
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Reveal topic tags
HCSSiM
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enya_yurself
69 posts
enya_yurself
#1 h  Mar 17, 2025, 11:13 PM
Y by
do they send the Interesting Test to everyone who applied or do they read the friendly letter first and only send to the kids they like?
Z K Y
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lpieleanu
2807 posts
lpieleanu
#2 h  Mar 17, 2025, 11:23 PM
Y by
In the automated email following a submission of the preliminary form, it states that the Interesting Test will be sent on March 17, so it is sent to everyone.
Z K Y
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Magnetoninja
270 posts
Magnetoninja
#3 h  Mar 18, 2025, 1:35 AM
Y by
I believe they send to kids they like, I could be wrong tho
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dppvlit123
15 posts
dppvlit123
#4 h  Tuesday at 7:30 PM
Y by
Probably not, they emailed me 4 minutes after I sent mine in
Z K Y
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akliu
1726 posts
akliu
#5 h  Yesterday at 7:54 PM
Y by
to those who have already done HCSSiM applications before, when I want to submit the Interesting Test, do I just scan a printed out version of the test with my pencil work on there? also, do you think it would be fine if I just provided a latex-ed solutions document instead?
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