证明:
∵AD平分∠BAC
∴∠BAD=∠CAD
∵EF垂直平分AD
∴AF=DF
∴∠FAD=∠FDA
∵∠FAD=∠CAF+∠CAD,∠FDA=∠B+∠BAD(∠FDA是△ABD的外角)
∴∠CAF=∠B