One difficulty faced by any mathematics teacher who wants to present material online is formatting of their documents. Ideally, you’d like to be able to add equations to your online documents as easily as you can to Microsoft Word. Unfortunately, this is not the case.
Over the past three years, I have researched a number of options. There are no simple solutions to this problem, just solutions with varying degrees of difficulty. A number of these solutions are within reach for your students to use as well, should your students be involved with any of your online projects.
The simplest solution I have found is unfortunately using a propietary program. Basically the steps are as follows. You open up Microsoft Word, and confirm you have the bundled Equation Editor installed. This is likely to be true in Word 2003, and virtually assured in Word 2007.
Basically the steps are as follows. You create the equation using Equation Editor. It really is one of the easiest programs to use. Unfortunately, in both 2003 and 2007, the equation is not immediately an image, it is and object in a Word document, so you need to find a way to export it out of the program. If you are using 2003, what you basically create a screen-shot of what appears in your monitor, and paste the result into a simple image editor. Crop the screen-shot appropriately, save it as a file, and you are good to upload your image for insertion into your online document. In 2007 you don’t need to create a screen-shot, you can just go to File ⇒ Save As ⇒Word 2003. Microsoft Word automatically converts all of the equations in your document to images, which you can then Copy and Paste into some image editing software one at a time and save as pictures.
The benefit of this process is that the creation of the equations is relatively straight forward. However, this process is a bit tedious especially if you have a lot of equations to produce.
Another option is to create the equations is to use an online equation editor such as the one available at http://www.sitmo.com/latex/. This allows you to enter in LaTeX and produce an image of your equation. So you enter the very cryptic x = \frac {-b \pm \sqrt{b^2-4ac}}{2a} and it turns it into the equation 
. Fortunately on the page in question their editor allows you to modify the LaTeX using some buttons, which simplifies the process. You can also preview the result of your LaTeX to make sure it is correct. You then save the resulting preview image to your computer, and upload and insert it into your post.
There are two problems with this solution. The first is that if Sitmo goes out of business, you lose the ability to add equations in this manner. The second problem is that you again, have to create each equation one at a time, and upload them one at a time to your online document. The benefit of this solution is that it doesn’t require you to install any software and will work on any computer, anywhere.
A third solution is to host your own CGI on your server to convert your own LaTeX that you type into your interface to create the documents, and it is converted automatically into an equation image for you. This is ideal, except that whether or not it works depends a lot on your server set up, and what content management system you are using. For Drupal there is a module you can add which does this, called Mathfilter which I know works, since I wrote the module. You can use it, and apply a patch suggested by one of the Drupal developers, to produce very similar equations. [tex]x = \frac {-b \pm \sqrt{b^2-4ac}}{2a}[/tex] becomes using the filter.
The problems with this 3rd solution are numerous which essentially all boil down to needing some technical expertise to install the system, and needing knowledge of LaTeX to use it. The benefit is, you become in charge of when and where you insert equations into your documents, and you can insert them on the fly as you create your document.
Whatever method you choose, it is clear that including mathematical equations online is feasible, even if none of the solutions is really mature.