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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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camp/class recommendations for incoming freshman
walterboro   11
N 2 hours ago by Pengu14
hi guys, i'm about to be an incoming freshman, does anyone have recommendations for classes to take next year and camps this summer? i am sure that i can aime qual but not jmo qual yet. ty
11 replies
+1 w
walterboro
May 10, 2025
Pengu14
2 hours ago
J
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Metamorphosis of Medial and Contact Triangles
djmathman   102
N 2 hours ago by Mathandski
Source: 2014 USAJMO Problem 6
Let $ABC$ be a triangle with incenter $I$, incircle $\gamma$ and circumcircle $\Gamma$. Let $M,N,P$ be the midpoints of sides $\overline{BC}$, $\overline{CA}$, $\overline{AB}$ and let $E,F$ be the tangency points of $\gamma$ with $\overline{CA}$ and $\overline{AB}$, respectively. Let $U,V$ be the intersections of line $EF$ with line $MN$ and line $MP$, respectively, and let $X$ be the midpoint of arc $BAC$ of $\Gamma$.

(a) Prove that $I$ lies on ray $CV$.

(b) Prove that line $XI$ bisects $\overline{UV}$.
102 replies
1 viewing
djmathman
Apr 30, 2014
Mathandski
2 hours ago
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ranttttt
alcumusftwgrind   41
N 3 hours ago by meyler
rant
41 replies
alcumusftwgrind
Apr 30, 2025
meyler
3 hours ago
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high tech FE as J1?!
imagien_bad   62
N 3 hours ago by jasperE3
Source: USAJMO 2025/1
Let $\mathbb Z$ be the set of integers, and let $f\colon \mathbb Z \to \mathbb Z$ be a function. Prove that there are infinitely many integers $c$ such that the function $g\colon \mathbb Z \to \mathbb Z$ defined by $g(x) = f(x) + cx$ is not bijective.
Note: A function $g\colon \mathbb Z \to \mathbb Z$ is bijective if for every integer $b$, there exists exactly one integer $a$ such that $g(a) = b$.
62 replies
imagien_bad
Mar 20, 2025
jasperE3
3 hours ago
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No more topics!
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9 Fun Proof Endings
elasticwealth   49
N Apr 25, 2025 by steve4916
It seems like AOPS is going through a stressful phase right now.

Let's lighten the mood by voting on the best proof endings!
49 replies
elasticwealth
Apr 24, 2025
steve4916
Apr 25, 2025
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Fun Proof Endings
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elasticwealth
342 posts
elasticwealth
#1 h  Apr 24, 2025, 12:26 AM • 3 Y
Y by clarkculus, Pengu14, Exponent11
9Poll:
Best Proof Ending?
267 Votes
21%
(55)
25%
(66)
16%
(42)
32%
(86)
7%
(18)
Hide Results Show Results
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It seems like AOPS is going through a stressful phase right now.

Let's lighten the mood by voting on the best proof endings!
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UberPiggy
43 posts
UberPiggy
#2 h  Apr 24, 2025, 12:28 AM • 1 Y
Y by ninjaforce
"And we are done" + "An empty square" is what I usually go with
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elasticwealth
342 posts
elasticwealth
#4 h  Apr 24, 2025, 12:28 AM
Y by
$Q$$\mathcal{E}$$D$. is my favorite.
This post has been edited 1 time. Last edited by elasticwealth, Apr 24, 2025, 12:29 AM
Reason: latex
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clarkculus
243 posts
clarkculus
#5 h  Apr 24, 2025, 12:29 AM • 6 Y
Y by OronSH, centslordm, ehuseyinyigit, Exponent11, wikjay, arfekete
“as desired.”
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Pengu14
626 posts
Pengu14
#6 h  Apr 24, 2025, 12:29 AM
Y by
I did a filled square susus
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megarnie
5610 posts
megarnie
#7 h  Apr 24, 2025, 12:30 AM
Y by
for the end of a proof of a problem, i usually don't write anything to show it's done but at the end of a proof of a claim i use white square
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Shan3t
374 posts
Shan3t
#8 h  Apr 24, 2025, 12:31 AM • 4 Y
Y by BS2012, Alex-131, ehuseyinyigit, Exponent11
You cant go wrong with the "And we are done" ending
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jkim0656
1032 posts
jkim0656
#9 h  Apr 24, 2025, 12:42 AM • 1 Y
Y by Exponent11
i like the empty square
it seems like aops written lol
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llddmmtt1
425 posts
llddmmtt1
#10 h  Apr 24, 2025, 12:46 AM • 2 Y
Y by Exponent11, Miquel-point
my fav is "and we done yayyy"
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Martin2001
156 posts
Martin2001
#11 h  Apr 24, 2025, 12:48 AM • 3 Y
Y by jkim0656, elasticwealth, ehuseyinyigit
and we're done$.\blacksquare$
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maxamc
580 posts
maxamc
#12 h  Apr 24, 2025, 12:49 AM
Y by
I always end with $\blacksquare$, and before that I say "we are done", "as desired" or something similar.
This post has been edited 1 time. Last edited by maxamc, Apr 24, 2025, 1:03 AM
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NamelyOrange
512 posts
NamelyOrange
#13 h  Apr 24, 2025, 2:38 AM
Y by 
KYU
EEE
DEE
!!!

(best ending trust)

just kidding, I normally use an empty square.
Attachments:
This post has been edited 3 times. Last edited by NamelyOrange, Apr 24, 2025, 2:45 AM
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AAAbattery
5 posts
AAAbattery
#14 h  Apr 24, 2025, 2:58 AM • 16 Y
Y by elasticwealth, NamelyOrange, expiredcraker, Amkan2022, vadava_lx, llddmmtt1, Andrew2019, LawofCosine, zhoujef000, OronSH, dragon888, ehuseyinyigit, Exponent11, scannose, clarkculus, carcool0
"Left as an exercise to the reader."
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justJen
1957 posts
justJen
#15 h  Apr 24, 2025, 3:13 AM • 1 Y
Y by Exponent11
QED :) $ $
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vadava_lx
161 posts
vadava_lx
#16 h  Apr 24, 2025, 3:20 AM • 2 Y
Y by Exponent11, Speedysolver1
i so sigma yay
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