Exclude PAGES from search

Hi, I’d like to know please how to exclude certain PAGES from search results.
I used this script on other WP sites, but I don’t figure out where to use it with Mantra!!

<?php
function filter_where($where = ”) {
if ( is_search() ) {
$exclude = array(534,539);

for($x=0;$x<count($exclude);$x++){
$where .= ” AND ID != “.$exclude[$x];
}
}
return $where;
}
add_filter(‘posts_where’, ‘filter_where’);
?>

Mantra is great!
Thanks!