# Font Awesome macros not displaying correct symbols in math mode

Just wondering if anyone knows why the symbols from the fontawesome package do not show up correctly here (in the underbrace). For example the Twitter logo works fine when not in the align part, but inside it does not work. I have tried using \text{\faTwitter} but this also does not work. Note that this is just a small section from a larger align stream of equations.

.

\documentclass[12pt]{article}
\usepackage{fontawesome}
\usepackage{amsmath}
\begin{document}

\begin{align*}
\text{(this)} &= E \cdot e^{-r(T-t)} \cdot \Phi'\left[d(S,t) - \sigma \sqrt{T-t}\right] \cdot \underbrace{\frac{\partial}{\partial \sigma} \Bigg[ d(S,t) - \sigma \sqrt{T-t} \Bigg]}_{\faTwitter}
\end{align*}
\end{document}

• Welcome to TeX.SX! You can have a look at our starter guide to familiarize yourself further with our format. – ebosi Apr 22 '16 at 13:48
• \text{\faTwitter} works (-; – ebosi Apr 22 '16 at 13:49
• Thank you @ebo I must have made a typo when trying this before – Luke Porter Apr 22 '16 at 13:52

You need to escape the math mode with \text{} to use fontawesome macros.
\documentclass{article}