How to exclude specific blog categories from blog archive page

				
					function exclude_category( $query ) {
   if ( $query->is_home() && $query->is_main_query() ) {
   $query->set( 'cat', '-1, -2' ); //The IDs of the categories to exclude.
   }
   }
   add_action( 'pre_get_posts', 'exclude_category' );