Can I write an Equation on a HTML button?

Question

Apart from using image on the button, how can I write X^Y on the HTML button?

Answer 1

Assuming you mean X^Y then <button>X<sup>Y</sup></button>

If you were being literal, then <button>X^Y</button>

Answer 2

If you're looking to have even more complex equations displayed on a webpage, not just as text in your button. Here is an interesting page that talks about math expressions and HTML.