∵∠ACB=90°,CD⊥AB
∴∠FDB=∠ECB=90°
∵BE平分∠ABC
∴∠DBF=∠CBE(∠ABE=∠CBE)
∴∠CEF=90°-∠CBE
∠DFB=90°-∠DBF
∴∠CEF=∠DFB
∵∠DFB=∠CFE
∴∠CEF=∠CFE