math in html
The top-level element in MathML is <math>. Every valid MathML instance must be wrapped in <math> tags. In addition you must not nest a second <math> element in another, but you can have an arbitrary number of other child elements in it.
Examples
Theorem of Pythagoras
HTML5 notation
<!DOCTYPE html>
<html>
<head>
<title>MathML in HTML5</title>
</head>
<body>
<math>
<mrow>
<mrow>
<msup>
<mi>a</mi>
<mn>2</mn>
</msup>
<mo>+</mo>
<msup>
<mi>b</mi>
<mn>2</mn>
</msup>
</mrow>
<mo>=</mo>
<msup>
<mi>c</mi>
<mn>2</mn>
</msup>
</mrow>
</math>
</body>
</html>