BE=4ME,
连结AE,在BE上取点M,使BE=4ME,连结FM、B 1M、FB 1.在△BEA中,∵BE=4ME,AB=4AF,∴MF∥AE.又在平面AA 1C 1C中,易证C 1D∥AE,∴C 1D∥FM.∵C 1D
平面FMB 1,FM
平面FMB 1,∴C 1D∥平面B 1FM.
BE=4ME,
连结AE,在BE上取点M,使BE=4ME,连结FM、B 1M、FB 1.在△BEA中,∵BE=4ME,AB=4AF,∴MF∥AE.又在平面AA 1C 1C中,易证C 1D∥AE,∴C 1D∥FM.∵C 1D
平面FMB 1,FM
平面FMB 1,∴C 1D∥平面B 1FM.