htaccess and also 301 reroutes - multiple domains

I have the adhering to which reroutes mydomain1.co.uk and also mydomain1.com to www.mydomain1.com flawlessly.

RewriteCond %{HTTP_HOST} !^(.*)\.mydomain1\.com$ [NC]
RewriteRule ^(.*)$ http://www.mydomain1.com/$1 [R=301,L]

I am attempting to add an added regulation momentarily domain name, that will certainly reroute all non www website traffic for mydomain2.com to www.mydomain2.com.

Many thanks!