How do I remove 'untitled' partition from terminal or disk utility?
Ok. Nothing on disk3 needs changing yet, so all the CS commands are dangerous or ineffective

What happens when you issue:

diskutil eraseVolume free free disk0s4
diskutil eraseVolume free free disk0s3


Also, please use care, if you delete the wrong 0s4 you will lose everything. Do you have a backup and internet to reinstall if you or I make a mistake?