diff --git a/main/math.tex b/main/math.tex
index 0c8c651..d2158d7 100644
--- a/main/math.tex
+++ b/main/math.tex
@@ -16,6 +16,7 @@
 \newcommand{\C}{\mathbb{C}}
 \newcommand{\Q}{\mathbb{Q}}
 \newcommand{\Z}{\mathbb{Z}}
+\newcommand{\E}{\mathbb{E}}
 \newcommand{\8}{\infty}
 \newcommand{\dx}{\mbox{d}}
 \newcommand{\floor}[1]{\left\lfloor #1 \right\rfloor}