WordPress featured image in RSS feed

functions.php

// Add to functions.php or wherever you extend your functionality.
function featuredtoRSS($content) {
	global $post;
if ( has_post_thumbnail( $post->ID ) ){
	$content = '<div>' . get_the_post_thumbnail( $post->ID, 'medium', array( 'style' => '' ) ) . '</div>' . $content;
}
	return $content;
}
add_filter('the_excerpt_rss', 'featuredtoRSS');
add_filter('the_content_feed', 'featuredtoRSS');