WPMS and Root directory (stuck with it)

my blog site is:

http://example.com/wordpress , My subdirectory is under var/html/wordpress

am trying to rewrite the url as to : http://example.com described in many posts but for some reason it doesn’t work. I haveve been stuck in this for two weeks now

I change values in the database: site url and home to:
siteurl: http://example.com
Home: http://example.com/wordpress

2-copy index.php and httacces to the root: Html folder or www folder?
however i tried both.

3-added /wordpress/ in the index file as instructed

am not sure what am doing wrong?

below is my wp-config:

define('MULTISITE', true);
define('SUBDOMAIN_INSTALL', false);
define('DOMAIN_CURRENT_SITE', 'example.com');
define('PATH_CURRENT_SITE', '/wordpress/');
define('SITE_ID_CURRENT_SITE', 1);
define('BLOG_ID_CURRENT_SITE', 1);

below is my httacces:

RewriteEngine On
RewriteBase /wordpress/
RewriteRule ^index\.php$ - [L]

# add a trailing slash to /wp-admin
RewriteRule ^([_0-9a-zA-Z-]+/)?wp-admin$ $1wp-admin/ [R=301,L]

RewriteCond %{REQUEST_FILENAME} -f [OR]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^ - [L]
RewriteRule ^([_0-9a-zA-Z-]+/)?(wp-(content|admin|includes).*) $2 [L]
RewriteRule ^([_0-9a-zA-Z-]+/)?(.*\.php)$ $2 [L]
RewriteRule . index.php [L]