证明：连接DH,AF∵EF是AD的垂直平分线∴①AH=DH,则∠HAD=∠HDA∵∠BAD=∠CAD【AD平分∠BAC】∴∠BAD=∠HDA∴DH//AB ②AF=DF∴∠FAD =∠FDA ∴∠FAD -∠HAD=∠FDA-∠HDA即∠FAC=∠FDH∵DH//AB∴∠FDH=∠B∴∠FAC=∠B...谁说EF是AD的垂直平分线了？AD的垂直平分线交AB于G,交AD于E，交AC于H，交BC的延长线 于FAD的垂直平分线，G,E,H,F四点一线