Here's some, but not all, of the JavaScript math operators:
Code:
<script type="text/javascript">
//<![CDATA[
x = 2;
y = 6;
document.write("x : ", x, "<br>");
document.write("y : ", y, "<br>");
document.write("z = x + y : ", x+y, "<br>");
document.write("z = y - x : ", y-x, "<br>");
document.write("z = x * y : ", x*y, "<br>");
document.write("z = y / x : ", y/x, "<br>");
document.write("z = y % x : ", y%x, " (modulus divides numbers and returns remainder)<br>");
document.write("x += y : ", x+=y, " (same as x = x +y. \"+=\" is also an assignment operator.)<br>");
//]]>
</script>
Output: