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}