Re: Mathematical Notation.
In the Mathematica notebook session: Maybe the easiest way for Mathematica end-users is to right-click on the cell bracket of a 2D-formatted formula and choose "Copy As" "LaTeX" from the context menu.
Back on this forum: we wrap the pasted code by entering "$"-signs as described, whereas on other MathJax-supported forums one must enter "\(" and "\)" for wrapping the pasted code, so that MathJax can start recognizing and interpreting.
Very good to know, thanks raspi!