JSFiddle - React, Tailwind, and code Playground
HTML
<img src="http://www.clker.com/cliparts/m/v/m/J/4/V/dice-1-md.png" name="mydice">
<img src="http://www.clker.com/cliparts/a/Y/E/o/z/t/dice-2-md.png" name="mydice">
<form>
<input type="button" value="Roll" onclick="rollDice()">
</form>
JavaScript
var faces=[]
var numFaces=6;
for(var i=1;i<=numFaces;i++){
var img=new Image();
img.src='dice-'+i+'-md.png';
faces.push(img);
}
window.rollDice=function(){
var randomdice= Math.floor(Math.random()*numFaces);
document.images["mydice"].src=faces[randomdice].src;
}