In yet another contest-based post, I want to distinguish between two types of thinking: things that could help you solve a problem, and things that could help you understand the problem better. Then I'll talk a little about how you can use the latter. (I've talked about this in my own classes for a while… Continue reading Hard and soft techniques

# Category: Problem Solving

## Math contest platitudes, v3

I think it would be nice if every few years I updated my generic answer to "how do I get better at math contests?". So here is the 2019 version. Unlike previous instances, I'm going to be a little less olympiad-focused than I usually am, since these days I get a lot of people asking… Continue reading Math contest platitudes, v3

## Some Thoughts on Olympiad Material Design

(This is a bit of a follow-up to the solution reading post last month. Spoiler warnings: USAMO 2014/6, USAMO 2012/2, TSTST 2016/4, and hints for ELMO 2013/1, IMO 2016/2.) I want to say a little about the process which I use to design my olympiad handouts and classes these days (and thus by extension the… Continue reading Some Thoughts on Olympiad Material Design

## On Reading Solutions

(Ed Note: This was earlier posted under the incorrect title "On Designing Olympiad Training". How I managed to mess that up is a long story involving some incompetence with Python scripts, but this is fixed now.) Spoiler warnings: USAMO 2014/1, and hints for Putnam 2014 A4 and B2. You may want to work on these… Continue reading On Reading Solutions

## Putnam 2015 Aftermath

(EDIT: These solutions earned me a slot in N1, top 16.) I solved eight problems on the Putnam last Saturday. Here were the solutions I found during the exam, plus my repaired solution to B3 (the solution to B3 I submitted originally had a mistake). Some comments about the test. I thought that the A… Continue reading Putnam 2015 Aftermath

## The Mixtilinear Incircle

This blog post corresponds to my newest olympiad handout on mixtilinear incircles. My favorite circle associated to a triangle is the $latex {A}&fg=000000$-mixtilinear incircle. While it rarely shows up on olympiads, it is one of the richest configurations I have seen, with many unexpected coincidences showing up, and I would be overjoyed if they become… Continue reading The Mixtilinear Incircle

## Teaching A* USAMO Camp

In the last week of December I got a position as the morning instructor for the A* USAMO winter camp. Having long lost interest in coaching for short-answer contests, I'd been looking forward to an opportunity to teach an olympiad class for ages, and so I was absolutely psyched for that week. In this post… Continue reading Teaching A* USAMO Camp

## Three Properties of Isogonal Conjugates

In this post I'll cover three properties of isogonal conjugates which were only recently made known to me. These properties are generalization of some well-known lemmas, such as the incenter/excenter lemma and the nine-point circle. 1. Definitions Let $latex {ABC}&fg=000000$ be a triangle with incenter $latex {I}&fg=000000$, and let $latex {P}&fg=000000$ be any point in… Continue reading Three Properties of Isogonal Conjugates

## What leads to success at math contests?

Updated version of generic advice post: Platitudes v3. I think this is an important question to answer, not the least of reasons being that understanding how to learn is extremely useful both for teaching and learning. [1] About a year ago [2], I posted my thoughts on what the most important things were in math… Continue reading What leads to success at math contests?

## Writing Olympiad Geometry

I always wondered whether I could generate olympiad geometry problems by simply drawing lines and circles at random until three lines looked concurrent, four points looked concyclic, et cetera. From extensive experience you certainly get the feeling that this ought to be the case -- there are tons and tons of problems out there but… Continue reading Writing Olympiad Geometry