【解答】(1)证明:∵DF∥BC,∠ACB=90°,∴∠CFD=90°,∵CD⊥AB,∴∠AEC=90°,在△AEC和△DFC中,
∠AEC=CFD∠ACE=∠DCFDC=AC,∴△AEC≌△DFC;(2)证明:∵△AEC≌△DFC,∴CE=CF,∠FDC=∠A=30°,∴AF=DE,∵AB⊥CD,∴∠DGB=60°,CE=12AC,∴CF=12AC,∴AF=CF,∴CE=DE,∴BC=BD,∴∠BDE=∠BCE=30°,∴∠BDG=60°,∴∠GBD=60°,∴∠BGD=∠GBD=∠GDB,∴△DGB是等边三角形;(3)解:∵DE=1,∴CF=1,∵∠EDG=30°,∴DF=3,EG=33,∴四边形FGEC的面积=S△DCF-S△DEG=12×3×1-12×33×1=33.