∵∠AOB=180°，∴∠1+∠3+∠COF=180°，∵∠FOC=90°，∠1=30°，∴∠3=60°，∠BOC=120°，∴∠AOD=120°，∵OE平分∠AOD，∴∠2= 1 2 ∠AOD=60°．
