Display formatted date

I trying to display yesterday's date, but for some reason nothing is displaying.

I have the following:

<?php
$yesterday = date('m/d/Y', mktime(0, 0, 0, date("m") , date("d") - 1, date("Y")));
?>

PHP:

And then:

<p> Last Updated On: <b><?php echo $yesterday; ?></b></p>

PHP:

Thanks for the help!

 

Wowzers, lets make it a little simpler for you

$yesterday = date("F j, Y, g:i a", strtotime("-1 day"));

echo $yesterday;

PHP:

 

Even simplier

<?php
$yesterday = date("m/d/Y", time() - 86400);
echo "<p> Last Updated On: <b>" . $yesterday . "</b></p>";
?>

Code (php):

 

Well I'm all for simplification.

Thanks!