tutorials

cheatsheets

A Crash Course in Group Theory: 20-page introduction to finite-dimensional group theory.
A Graphical Derivation of the Legendre Transform: 9-page derivation, with pictures, of the Legendre transform of a convex function.
A Short Guide to RSA Encryption: 5-page introduction to the mathematics of RSA encryption.
Easy Differential Equations: 8-page introduction to ordinary differential equations for scientists, engineers, investors, musicians, etc.
How to Calculate Interest: 28-page introduction to compound interest with formulas for mortgages, student loans, and credit cards.
How to Use Kirchhoff's Laws: 2-page example problem solved with Kirchhoff's circuit laws.