delete synced media from ipadn

Assuming that you want to remove (rather than delete) music from your iPad, use the screenshot below as your guide to look on the device (from iTunes) at the Device/Settings/Music pane (1.). On that pane you can use the option to Sync selected playlists, artists, albums and genres (3.):

Using that option will then show the options in section 4. where you select only what you want on the iPad. iTunes will remove any music not selected for Sync. There are additional sections labelled Genres and Albums further down the pane. Having made your selection, tap the Sync (or Apply) button in the lower right corner of the iTunes window (not shown in the screenshot).