Equations in HTML

Here are some ideas for how to include equations in HTML documents.

Candidates

Full MathML:

<math xmlns="http://www.w3.org/1998/Math/MathML">
 <mi>x</mi>
 <mo>=</mo>
 <mfrac>
  <mrow>
   <mo>-</mo>
   <mi>b</mi>
   <mo>±</mo>
   <msqrt>
    <msup>
     <mi>b</mi>
     <mn>2</mn>
    </msup>
    <mo>-</mo>
    <mn>4</mn>
    <mo>⁢</mo>
    <mi>a</mi>
    <mo>⁢</mo>
    <mi>c</mi>
   </msqrt>
  </mrow>
  <mrow>
   <mn>2</mn>
   <mo>⁢</mo>
   <mi>a</mi>
  </mrow>
 </mfrac>
</math>

MathML, but with <mo>, <mi>, and <mn> implied:

<math>
 x =
 <mfrac>
  <mrow>
   - b ±
   <msqrt>
    <msup> b 2 </msup>
    - 4 ⁢ a ⁢ c
   </msqrt>
  </mrow>
  <mrow>
   2 ⁢ a
  </mrow>
 </mfrac>
</math>

Rejected

LaTeX:

<math>x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}</math>

Research

Only presentational MathML: http://mathcast.sourceforge.net/fields.xml http://www-math.mit.edu/18.013A/MathML/chapter06/section01.xhtml http://golem.ph.utexas.edu/category/ http://pear.math.pitt.edu/mathzilla/Examples/markupOftheWeek.mhtml http://dlmf.nist.gov/Contents/GA/13/

Content MathML, converted to Presentational MathML using XSLT and/or script: http://www.math.uah.edu/stat/point/Sufficient.xhtml