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Scores are out for jmo
imagien_bad   138
N 7 minutes ago by vincentwant
RIP..................
138 replies
+2 w
imagien_bad
Yesterday at 6:10 PM
vincentwant
7 minutes ago
PAMO Problem 4: Perpendicular lines
DylanN   11
N 16 minutes ago by ATM_
Source: 2019 Pan-African Mathematics Olympiad, Problem 4
The tangents to the circumcircle of $\triangle ABC$ at $B$ and $C$ meet at $D$. The circumcircle of $\triangle BCD$ meets sides $AC$ and $AB$ again at $E$ and $F$ respectively. Let $O$ be the circumcentre of $\triangle ABC$. Show that $AO$ is perpendicular to $EF$.
11 replies
DylanN
Apr 9, 2019
ATM_
16 minutes ago
Red Mop Chances
imagien_bad   45
N 21 minutes ago by xTimmyG
What are my chances of making red mop with a 35 on jmo?
45 replies
imagien_bad
Mar 22, 2025
xTimmyG
21 minutes ago
Coordbashing = 0?
UberPiggy   5
N 26 minutes ago by elasticwealth
Hi,

I just received my USAJMO score distribution: 000 701 (very cursed I know)

The thing is, I solved #5 (Geometry) by using Cartesian coordinates and tried to show a lot of detail in my calculations. I don't think I mislabeled the pages or anything either. I don't have the scans, but does anyone know why this might be the case? Thank you!
5 replies
UberPiggy
42 minutes ago
elasticwealth
26 minutes ago
9 Zero on USAMO => Cheater?
jcoons91   2
N 27 minutes ago by NoSignOfTheta
See poll
2 replies
jcoons91
29 minutes ago
NoSignOfTheta
27 minutes ago
P2 Solution Misgrade?
Mathandski   10
N 37 minutes ago by KevinChen_Yay
Can someone explain to me how this is a zero and not a 5? I wrote the Vieta's equivalent of "two consec zero coefficients", which was worth 5 points

I messed up the numbering and I believe that is the underlying cause of the misgrade but if someone sees any other error, please let me know so I don't wrongly email MAA.

Update: I posted this while flipping out upon seeing a zero on my P2 wanting to find a way to somehow appeal - it genuinely felt like 24JMO4 all over again. Thankfully, this -5 did not game-end my score this year
10 replies
Mathandski
Yesterday at 8:03 PM
KevinChen_Yay
37 minutes ago
9 USA(J)MO Grading Poll
elasticwealth   12
N 37 minutes ago by KevinChen_Yay
Please vote honestly. If you did not compete in the USA(J)MO, please do not vote.
12 replies
elasticwealth
Today at 3:17 AM
KevinChen_Yay
37 minutes ago
awards seem to be out
LearnMath_105   24
N 40 minutes ago by KevinChen_Yay
title xooks
24 replies
LearnMath_105
Today at 3:29 PM
KevinChen_Yay
40 minutes ago
2025 ELMOCOUNTS - Mock MATHCOUNTS Nationals
vincentwant   109
N an hour ago by Bummer12345
text totally not copied over from wmc (thanks jason <3)
Quick Links:
[list=disc]
[*] National: (Sprint) (Target) (Team) (Sprint + Target Submission) (Team Submission) [/*]
[*] Miscellaneous: (Leaderboard) (Sprint + Target Private Discussion Forum) (Team Discussion Forum)[/*]
[/list]
-----
Eddison Chen (KS '22 '24), Aarush Goradia (CO '24), Ethan Imanuel (NJ '24), Benjamin Jiang (FL '23 '24), Rayoon Kim (PA '23 '24), Jason Lee (NC '23 '24), Puranjay Madupu (AZ '23 '24), Andy Mo (OH '23 '24), George Paret (FL '24), Arjun Raman (IN '24), Vincent Wang (TX '24), Channing Yang (TX '23 '24), and Jefferson Zhou (MN '23 '24) present:



[center]IMAGE[/center]

[center]Image credits to Simon Joeng.[/center]

2024 MATHCOUNTS Nationals alumni from all across the nation have come together to administer the first-ever ELMOCOUNTS Competition, a mock written by the 2024 Nationals alumni given to the 2025 Nationals participants. By providing the next generation of mathletes with free, high quality practice, we're here to boast how strong of an alumni community MATHCOUNTS has, as well as foster interest in the beautiful art that is problem writing!

The tests and their corresponding submissions forms will be released here, on this thread, on Monday, April 21, 2025. The deadline is May 10, 2025. Tests can be administered asynchronously at your home or school, and your answers should be submitted to the corresponding submission form. If you include your AoPS username in your submission, you will be granted access to the private discussion forum on AoPS, where you can discuss the tests even before the deadline.
[list=disc]
[*] "How do I know these tests are worth my time?" [/*]
[*] "Who can participate?" [/*]
[*] "How do I sign up?" [/*]
[*] "What if I have multiple students?" [/*]
[*] "What if a problem is ambiguous, incorrect, etc.?" [/*]
[*] "Will there be solutions?" [/*]
[*] "Will there be a Countdown Round administered?" [/*]
[/list]
If you have any other questions, feel free to email us at elmocounts2025@gmail.com (or PM me)!
109 replies
vincentwant
Apr 20, 2025
Bummer12345
an hour ago
A lot of integer lengths: JMO #6 or USAMO Problem 4
BarbieRocks   81
N 2 hours ago by lpieleanu
Let $ABC$ be a triangle with $\angle A = 90^{\circ}$. Points $D$ and $E$ lie on sides $AC$ and $AB$, respectively, such that $\angle ABD = \angle DBC$ and $\angle ACE = \angle ECB$. Segments $BD$ and $CE$ meet at $I$. Determine whether or not it is possible for segments $AB$, $AC$, $BI$, $ID$, $CI$, $IE$ to all have integer lengths.
81 replies
BarbieRocks
Apr 29, 2010
lpieleanu
2 hours ago
AMC 10/AIME study discord server
mathkidAP   2
N 2 hours ago by mathkidAP
I have created a discord server for AMC 10/AIME studying. Please PM me if you would like to join the sever. It will be open to anyone who would like to join.
2 replies
mathkidAP
2 hours ago
mathkidAP
2 hours ago
V \le RS/2 in tetrahderon with equil base
Miquel-point   1
N Apr 8, 2025 by kiyoras_2001
Source: Romanian IMO TST 1981, Day 4 P2
Consider a tetrahedron $OABC$ with $ABC$ equilateral. Let $S$ be the area of the triangle of sides $OA$, $OB$ and $OC$. Show that $V\leqslant \dfrac12 RS$ where $R$ is the circumradius and $V$ is the volume of the tetrahedron.

Stere Ianuș
1 reply
Miquel-point
Apr 6, 2025
kiyoras_2001
Apr 8, 2025
V \le RS/2 in tetrahderon with equil base
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Source: Romanian IMO TST 1981, Day 4 P2
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Miquel-point
472 posts
#1 • 2 Y
Y by PikaPika999, kiyoras_2001
Consider a tetrahedron $OABC$ with $ABC$ equilateral. Let $S$ be the area of the triangle of sides $OA$, $OB$ and $OC$. Show that $V\leqslant \dfrac12 RS$ where $R$ is the circumradius and $V$ is the volume of the tetrahedron.

Stere Ianuș
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kiyoras_2001
674 posts
#2
Y by
See Bulgaria 1990 P6.
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