You can type mathematical symbols into emacs using the TeX input method. C-\ TeX <enter> \ohm \therefore \pi C-\ will toggle the input method on and off. Note the \ indicator in the bottom left of the status bar.
I came accross this great tool for displaying mathematical equations the other day. MathJax not only supports \(\LaTeX\) syntax but also renders the equations as pure text, so no unsightly images and they scale beautifully. You can also right click on the equation and see it’s \(\LaTeX\) code. The code for MathJax is open source, […]