Teaching
In summer 2014 and 2015, I taught the math camp for incoming students to the econ PhD program at Columbia. I wrote the following lecture notes, which cover much of the mathematical tools needed in economics. If you are starting an econ or econ-related program and want to brush up on your math, feel free to use them (also: congratulations on your admission!). Associated problem sets and their solutions are available on the 2014 and 2015 math camp websites.
2. Analysis
4. Convexity