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k a My Retirement & New Leadership at AoPS
rrusczyk   1571
N Mar 26, 2025 by SmartGroot
I write today to announce my retirement as CEO from Art of Problem Solving. When I founded AoPS 22 years ago, I never imagined that we would reach so many students and families, or that we would find so many channels through which we discover, inspire, and train the great problem solvers of the next generation. I am very proud of all we have accomplished and I’m thankful for the many supporters who provided inspiration and encouragement along the way. I'm particularly grateful to all of the wonderful members of the AoPS Community!

I’m delighted to introduce our new leaders - Ben Kornell and Andrew Sutherland. Ben has extensive experience in education and edtech prior to joining AoPS as my successor as CEO, including starting like I did as a classroom teacher. He has a deep understanding of the value of our work because he’s an AoPS parent! Meanwhile, Andrew and I have common roots as founders of education companies; he launched Quizlet at age 15! His journey from founder to MIT to technology and product leader as our Chief Product Officer traces a pathway many of our students will follow in the years to come.

Thank you again for your support for Art of Problem Solving and we look forward to working with millions more wonderful problem solvers in the years to come.

And special thanks to all of the amazing AoPS team members who have helped build AoPS. We’ve come a long way from here:IMAGE
1571 replies
rrusczyk
Mar 24, 2025
SmartGroot
Mar 26, 2025
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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]
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
Mar 2, 2025
0 replies
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Modular Arithmetic and Integers
steven_zhang123   2
N 4 minutes ago by GreekIdiot
Integers \( n, a, b \in \mathbb{Z}^+ \) satisfies \( n + a + b = 30 \). If \( \alpha < b, \alpha \in \mathbb{Z^+} \), find the maximum possible value of $\sum_{k=1}^{\alpha} \left \lfloor \frac{kn^2 \bmod a }{b-k} \right \rfloor $.
2 replies
steven_zhang123
Mar 28, 2025
GreekIdiot
4 minutes ago
J
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f(x+y)f(z)=f(xz)+f(yz)
dangerousliri   30
N 6 minutes ago by GreekIdiot
Source: Own
Find all functions $f:\mathbb{R}\rightarrow\mathbb{R}$ such that for all irrational numbers $x, y$ and $z$,
$$f(x+y)f(z)=f(xz)+f(yz)$$
Some stories about this problem. This problem it is proposed by me (Dorlir Ahmeti) and Valmir Krasniqi. We did proposed this problem for IMO twice, on 2018 and on 2019 from Kosovo. None of these years it wasn't accepted and I was very surprised that it wasn't selected at least for shortlist since I think it has a very good potential. Anyway I hope you will like the problem and you are welcomed to give your thoughts about the problem if it did worth to put on shortlist or not.
30 replies
dangerousliri
Jun 25, 2020
GreekIdiot
6 minutes ago
J
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Unsolved NT, 3rd time posting
GreekIdiot   6
N 9 minutes ago by GreekIdiot
Source: own
Solve $5^x-2^y=z^3$ where $x,y,z \in \mathbb Z$
Hint
6 replies
GreekIdiot
Mar 26, 2025
GreekIdiot
9 minutes ago
J
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Need hint:''(
Buh_-1235   0
9 minutes ago
Source: Canada Winter mock 2015
Recall that for any positive integer m, φ(m) denotes the number of positive integers less than m which are relatively
prime to m. Let n be an odd positive integer such that both φ(n) and φ(n + 1) are powers of two. Prove n + 1 is power
of two or n = 5.
0 replies
Buh_-1235
9 minutes ago
0 replies
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No more topics!
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A_1C_1 = A_2C_2 wanted , tangential ABCD
parmenides51   0
Jun 14, 2021
Source: 2018 1st Kharkiv Masters Tournament X-XI 2.8
A circle $\Gamma$ is inscribed in the quadrilateral $ABCD$. The point $E$ is the point of intersection of $\Gamma$ with the diagonal $AC$, the closest to $A$. Tangent to $\Gamma$ at point $F$ intersects the lines $AB$ and $BC$ at points $A_1$ and $C_1$, respectively, and the lines $AD$ and $CD$ at points $A_2$ and $C_2$, respectively. Prove that $A_1C_1 = A_2C_2$.
0 replies
parmenides51
Jun 14, 2021
0 replies
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A_1C_1 = A_2C_2 wanted , tangential ABCD
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Reveal topic tags
geometry
equal segments
tangential quadrilateral
Kharkiv Masters
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G H BBookmark kLocked kLocked NReply
Source: 2018 1st Kharkiv Masters Tournament X-XI 2.8
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parmenides51
30629 posts
parmenides51
#1 h  Jun 14, 2021, 9:59 PM • 2 Y
Y by centslordm, Mango247
A circle $\Gamma$ is inscribed in the quadrilateral $ABCD$. The point $E$ is the point of intersection of $\Gamma$ with the diagonal $AC$, the closest to $A$. Tangent to $\Gamma$ at point $F$ intersects the lines $AB$ and $BC$ at points $A_1$ and $C_1$, respectively, and the lines $AD$ and $CD$ at points $A_2$ and $C_2$, respectively. Prove that $A_1C_1 = A_2C_2$.
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