Write maths, see maths is a jQuery plugin for editable areas which gives an instant MathJax preview of the TeX you're writing just above the cursor.
To use it, just call
$(selector).writemaths()$ when the page loads.
You can optionally pass in an object with some options:
cleanMaths: a function which does something to the LaTeX before displaying it.
callback: a function which is called when the preview is displayed.
iFrame: set this to
trueif you're applying writemaths to something like TinyMCE, which lives inside an iframe.
position: the position on the parent element on which to place the preview. It's really the `
atoption of jquery.ui.position.
previewPosition: the position on the preview element to line up with the parent element. It's really the
myoption of jquery.ui.position.
of: the element to position relative to.