Load mod_headers.c module for browser caching in joomla

I am trying to add the following into my htaccess file:

<IfModule mod_headers.c>
Header unset ETag
Header unset Last-Modified
</IfModule>
FileETag None
<FilesMatch "\\.(ico|gz|JPG|jpg|jpeg|png|gif|js|css|swf)$">
Header unset Cache-control
Header set Expires "access plus 1 month"
</FilesMatch>

I am not sure if I am supposed to put this in joomla/htdocs/.htaccess or in apache2/conf/httpd.conf or a combination of the two. Do I enable the module in httpd.conf and then add this code to the .htaccess file?