% \f is defined as #1f(#2) using the macro
\f\relax{x} = \int_{-\infty}^\infty
\f\hat\xi\,e^{2 \pi i \xi x}
\,d\xi
This is some text $math \frac12$ other text $\unsupported$
Other node \[ \text{displaymath} \frac{1}{2} \] blah $$ \int_2^3 $$
and some more text \(and math\) blah. And $math with a
\$ sign$.
Stuff in a $pre tag$
An AMS environment without $$…$$ delimiters.
\begin{equation} \begin{split} a &=b+c\\ &=e+f \end{split} \end{equation}