The file extension is ".xhtml".
The extension ".htm" doesn't allow the MathML to work.
The extension ".xml" displays the page fine, but it doesn't validate.

MathML (Math Markup Language)

This is an IMAGE of the "horizontal fraction" that
you will see below, if MathML is displaying properly:

MathML:
$\frac{x+1}{x+2}$

SVG (Scalable Vector Graphics)

This is an IMAGE of the circle that
you will see below, if SVG is displaying properly:

SVG:

DIV WITH DYNAMIC TEXT CONTAINING FORMATTED HTML CODE and MATHML

Performance of this web page in various browsers/platforms

March 24, 2010

static MathML?

SVG?

div with dynamic formatted text and MathML, using JavaScript

NOTES

Firefox (on MAC) (Version 3.6.2)

yes

yes

yes

So... Firefox gives EVERYTHING needed for dynamic math!

Internet Explorer (Version 8.0, implemented on the MAC with VMWare Fusion)

yes; uses MathPlayer plugin

yes: using Adobe SVG Player

no

no: nothing will appear in the div at all

Opera (on MAC) (Version 10.10)

yes

yes

yes

So... new versions of Opera give EVERYTHING needed for dynamic math!