This is the official manual for the latest Org-mode release.
Embedded LaTeX as described in Embedded LaTeX, will be correctly inserted into the LaTeX file. Furthermore, you can add special code that should only be present in LaTeX export with the following constructs:
Code within @@latex:some code@@ a paragraph. #+LATEX: Literal LaTeX code for export #+BEGIN_LATEX All lines between these markers are exported literally #+END_LATEX