不妨设D,E,F分别在边AB,BC,AC上.∵△ABC,△DEF为正三角形,∴∠A=∠B=∠C=60∠EDF=∠FED=∠EFD=60∠,DE=DF=EF∴∠BDE+∠ADF=180-60=120∠ADF+∠AFD=180-60=120∴∠AFD=∠BDE∴△ADF≌△BED同理△BED≌△CFE∴AD=BE=CF...