It's February and we'd love to help you find the right course plan!

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k a February Highlights and 2025 AoPS Online Class Information
jlacosta   0
Feb 2, 2025
We love to share what you can look forward to this month! The AIME I and AIME II competitions are happening on February 6th and 12th, respectively. Join our Math Jams the day after each competition where we will go over all the problems and the useful strategies to solve them!

2025 AIME I Math Jam: Difficulty Level: 8* (Advanced math)
February 7th (Friday), 4:30pm PT/7:30 pm ET

2025 AIME II Math Jam: Difficulty Level: 8* (Advanced math)
February 13th (Thursday), 4:30pm PT/7:30 pm ET

The F=ma exam will be held on February 12th. Check out our F=ma Problem Series course that begins February 19th if you are interested in participating next year! The course will prepare you to take the F=ma exam, the first test in a series of contests that determines the members of the US team for the International Physics Olympiad. You'll learn the classical mechanics needed for the F=ma exam as well as how to solve problems taken from past exams, strategies to succeed, and you’ll take a practice F=ma test of brand-new problems.

Mark your calendars for all our upcoming events:
[list][*]Feb 7, 4:30 pm PT/7:30pm ET, 2025 AIME I Math Jam
[*]Feb 12, 4pm PT/7pm ET, Mastering Language Arts Through Problem-Solving: The AoPS Method
[*]Feb 13, 4:30 pm PT/7:30pm ET, 2025 AIME II Math Jam
[*]Feb 20, 4pm PT/7pm ET, The Virtual Campus Spring Experience[/list]
AoPS Spring classes are open for enrollment. Get a jump on 2025 and enroll in our math, contest prep, coding, and science classes today! Need help finding the right plan for your goals? Check out our recommendations page!

Don’t forget: Highlight your AoPS Education on LinkedIn!
Many of you are beginning to build your education and achievements history on LinkedIn. Now, you can showcase your courses from Art of Problem Solving (AoPS) directly on your LinkedIn profile! Don't miss this opportunity to stand out and connect with fellow problem-solvers in the professional world and be sure to follow us at: https://www.linkedin.com/school/art-of-problem-solving/mycompany/ Check out our job postings, too, if you are interested in either full-time, part-time, or internship opportunities!

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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AMC 12 Problem Series
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Special AIME Problem Seminar B
Sat & Sun, Feb 1 - Feb 2 (4:00 - 7:00 pm ET/1:00 - 4:00 pm PT)

F=ma Problem Series
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0 replies
jlacosta
Feb 2, 2025
0 replies
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
I need this. Pls help me
Giahuytls2326   12
N 5 minutes ago by Giahuytls2326
Source: Own
Given $\triangle ABC$ , orthocenter $H$, $E$ is the center of Euler's circle of $\triangle ABC$. $X,Y,Z$ is the midpoint of $AH,BH,CH$. From $X,Y,Z$ draw the tangent of $(E)$, cut a line through $E$ perpendicular to sides $BC, CA,AB$ at $M,N,P$ .Prove that $AM,BN,CP$ concurrent
12 replies
Giahuytls2326
Thursday at 4:59 PM
Giahuytls2326
5 minutes ago
Thanks u!
Ruji2018252   4
N 6 minutes ago by sqing
Let $a,b,c>0$ and $a+b+c=abc$
Find minimum (and prove)
\[P=(ab-1)(bc+1)^6(ca-1)\]
4 replies
Ruji2018252
Yesterday at 2:38 PM
sqing
6 minutes ago
Functional Equation
AnhQuang_67   4
N 6 minutes ago by gordian.knot
Find all functions $f:\mathbb{R} \to \mathbb{R}$ satisfying: $$x^2f(x)+f(1-x)=2x-x^4, \forall x \in \mathbb{R} $$
4 replies
AnhQuang_67
Yesterday at 4:02 PM
gordian.knot
6 minutes ago
thanks u!
Ruji2018252   1
N 26 minutes ago by sqing
Let $a,b,c\in \mathbb{R},a,b,c\ne 0$ and $a+b+c=0.$ Find minimum (and prove)
\[C=\dfrac{b^2+c^2-a^2}{b^2+c^2}+\dfrac{c^2+a^2-b^2}{c^2+a^2}+\dfrac{a^2+b^2-c^2}{a^2+b^2}\]
1 reply
1 viewing
Ruji2018252
3 hours ago
sqing
26 minutes ago
No more topics!
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
Zero tolerance
G H J
G H BBookmark kLocked kLocked NReply
Source: Use your common sense! (enough is enough)
The post below has been deleted. Click to close.
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jlordhe
1965 posts
#36 • 10 Y
Y by Amir Hossein, Purple_Planet, pog, samrocksnature, jhu08, megarnie, ImSh95, Adventure10, Mango247, cubres
LoveMaths26102003 wrote:
Moderators are the ones with green usernames??

Blue usernames are site admins, red usernames are forum admins.
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Mathlete2017
3233 posts
#37 • 8 Y
Y by pog, samrocksnature, jhu08, megarnie, ImSh95, Adventure10, Mango247, cubres
jlordhe wrote:
LoveMaths26102003 wrote:
Moderators are the ones with green usernames??

Blue usernames are site admins, red usernames are forum admins.
Blue usernames with the X at the beginning, that is.
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RopuToran
609 posts
#38 • 7 Y
Y by pog, samrocksnature, jhu08, megarnie, ImSh95, Adventure10, cubres
Question: Is that OK when posting a geometry problem without any figure ?
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adityaguharoy
4655 posts
#39 • 8 Y
Y by pog, samrocksnature, jhu08, megarnie, ImSh95, Adventure10, Mango247, cubres
RopuToran wrote:
Question: Is that OK when posting a geometry problem without any figure ?

Yes that's perfectly fine. In fact the P6 of IMO 2018 had no figure in the official statement of the problem.
This post has been edited 1 time. Last edited by adityaguharoy, Sep 15, 2018, 12:09 PM
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RopuToran
609 posts
#40 • 9 Y
Y by Purple_Planet, pog, samrocksnature, jhu08, megarnie, ImSh95, Adventure10, Mango247, cubres
In IMO the problem was checked for several times :) But here, posting a figure will help other people know if the statement are true quickly.
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adityaguharoy
4655 posts
#41 • 7 Y
Y by pog, samrocksnature, jhu08, megarnie, ImSh95, Adventure10, cubres
RopuToran wrote:
In IMO the problem was checked for several times :) But here, posting a figure will help other people know if the statement are true quickly.

Although I agree that a picture can be worth more than a thousand words, but if someone can give a good description of what's going on in the problem then there is no need to add a picture. But if someone thinks that the problem will be easier to understand from the figure then adding a figure can be golden.
In other words, it is not necessary to add a figure, but if you want you can add one.
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stronto
607 posts
#43 • 30 Y
Y by govind7701, khan.academy, Arthur., SolemnSolver, integrated_JRC, Kayak, MathematicalPhysicist, ywq233, Wizard_32, OliverA, Varuneshwara, AopsUser101, Purple_Planet, Inconsistent, pog, spicemax, samrocksnature, Siddharth03, suvamkonar, jhu08, megarnie, snap7822, ImSh95, aidan0626, Adventure10, Mango247, idkk, NicoN9, kiyoras_2001, cubres
I want to disagree with (a), sometimes titles like "Chinese TST 2003, Problem 1" are useful, as it allows other users who took the test to find discussion threads easier.

I personally dislike 'creative titles' because they sometimes spoil the problem. Calling 2018 AIME II #14 "Projective Fun" would be a prime example, as it describes a method people would use to solve the problem.
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hydrohelium
245 posts
#45 • 14 Y
Y by khan.academy, integrated_JRC, Purple_Planet, pog, samrocksnature, Siddharth03, jhu08, megarnie, ImSh95, player01, Adventure10, Mango247, Mango247, cubres
Dear Maththinkers,

I too agree with ZetaX but I believe contest name are good titles.
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khan.academy
633 posts
#46 • 9 Y
Y by hydrohelium, Purple_Planet, pog, samrocksnature, jhu08, megarnie, ImSh95, Adventure10, cubres
hydrohelium wrote:
Dear Maththinkers,

I too agree with ZetaX but I believe contest name are good titles.

Yeah, I think the same.
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FedeX333X
792 posts
#47 • 9 Y
Y by OliverA, Purple_Planet, pog, samrocksnature, jhu08, megarnie, ImSh95, Adventure10, cubres
@above You can already specify that in "source".
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Danielmath12
34 posts
#49 • 10 Y
Y by hydrohelium, Purple_Planet, pog, samrocksnature, jhu08, megarnie, ImSh95, Adventure10, Mango247, cubres
I do agree with ZetaX, but I also agree with @above2 & @above3.
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mathroyal
443 posts
#54 • 9 Y
Y by Electro__Wizard, Purple_Planet, pog, samrocksnature, jhu08, megarnie, ImSh95, Adventure10, cubres
But, there are a lot of questions of contests that are not from the moderators of admins. Then, how can we post the problem in contest?(like amcs)
This post has been edited 1 time. Last edited by mathroyal, Feb 25, 2019, 3:16 PM
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skywalker321
1358 posts
#55 • 12 Y
Y by AlastorMoody, Danielmath12, Purple_Planet, v4913, pog, samrocksnature, jhu08, megarnie, ImSh95, Adventure10, Mango247, cubres
why would you post amc questions in hso when it says olympiads in it hmm
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hashtagmath
1600 posts
#56 • 19 Y
Y by AlastorMoody, Dr_Vex, Professor-Mom, Purple_Planet, nicarmt, v4913, pog, Bradygho, sotpidot, HamstPan38825, samrocksnature, megarnie, jhu08, EZmath2006, ImSh95, aidan0626, Adventure10, rty, cubres
cause they want to get their HSO posts up. to look like they're smart.
This post has been edited 1 time. Last edited by hashtagmath, May 1, 2019, 10:20 PM
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NoDealsHere
1632 posts
#57 • 15 Y
Y by RishiNandha_M, Purple_Planet, pog, crazyeyemoody907, sotpidot, samrocksnature, jhu08, megarnie, Scooby07, BunnyAoPS, ImSh95, aidan0626, Adventure10, QueenArwen, cubres
skywalker321 wrote:
why would you post amc questions in hso when it says olympiads in it hmm

no common sense
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