延长CE、DA,相交于点G.因为,AD‖BC,AE = EB ,所以,∠BCE = ∠FGE ,AG = BC .不妨设正方形ABCD的边长为 4 ,则 AF = 1 ,DF = 3 .因为,FG = AF+AG = 5 ,FC = √(CD2+DF2) = 5 ,所以,FG = FC ,可得：∠FCE = ∠FGE .综上...