// Get random image
var randImg = new Array('brochurefan1','brochurefan2','brochurefan3');
var randLink = new Array();
var max = randImg.length;
var num = Math.floor((Math.random() * max));
document.write('<img src="images/'+randImg[num]+'.jpg" alt="Cyhoeddiadau yr ydym wedi gweithio arnynt" width="157" height="192" />');