var inGoals = $(\'#inGoals\').val();
var targetGoals = $(\'#targetGoals\').val();

var r = 1;
for(i = targetGoals; i>0; i--){r = r * i;}
var e = 2.71828;
var $val = Math.pow(inGoals,targetGoals) * Math.pow(e,-inGoals)/r;
$(\'#rebox\').text(Math.round($val * 10000)/10000);

PHP代码：
$inGoals = 1.2;
$targetGoals = 2;
$r = 1;
for ($i = $targetGoals; $i>0; $i--) {
 $r = $r * $i;
}
$e = 2.71828;
$val = pow($inGoals,$targetGoals) * pow($e,-$inGoals)/$r;

echo $val;