Html Fraction tutorial

If you want to write fraction than you can write it easily but in html you have to set this for use. I have added the code bellow. If the client does not support CSS it will be rendered as plain text, still readable as a fraction.
<span class="frac">^something<span>/</span>_something</span><br /> <style>span.frac { display: inline-block; font-size: 80%; text-align: center; } span.frac > sup { display: block; border-bottom: 1px solid; font: inherit; } span.frac > span { display: none; } span.frac > sub { display: block; font: inherit; }</style>

Preview:
^tanA_tanB

The middle <span> serves only for the clients who do not render CSS - the text is still readable as something/something - and that's why you should place a space between the
integer and the fraction. You may want to change the font-size, because the resulting element may be a little taller than the other characters in the line, or you may want to use a relative position to shift it a little to the bottom. But the general idea, as presented here, may be enough for the basic use.