在棱长为a的正方体ABCD-A1B1C1D1中,E、F分别为DD1和BB1的中点. (1)证明:AEC1F是平行四边形; (2)在棱长为a的正方体ABCD-A1B1C1D1中,E、F分别为DD1和BB1的中点.(1)证明:AEC1F是平行四边形
来源:学生作业帮助网 编辑:作业帮 时间:2024/08/15 14:56:01
![在棱长为a的正方体ABCD-A1B1C1D1中,E、F分别为DD1和BB1的中点. (1)证明:AEC1F是平行四边形; (2)在棱长为a的正方体ABCD-A1B1C1D1中,E、F分别为DD1和BB1的中点.(1)证明:AEC1F是平行四边形](/uploads/image/z/6886556-44-6.jpg?t=%E5%9C%A8%E6%A3%B1%E9%95%BF%E4%B8%BAa%E7%9A%84%E6%AD%A3%E6%96%B9%E4%BD%93ABCD%EF%BC%8DA1B1C1D1%E4%B8%AD%2CE%E3%80%81F%E5%88%86%E5%88%AB%E4%B8%BADD1%E5%92%8CBB1%E7%9A%84%E4%B8%AD%E7%82%B9%EF%BC%8E+%EF%BC%881%EF%BC%89%E8%AF%81%E6%98%8E%EF%BC%9AAEC1F%E6%98%AF%E5%B9%B3%E8%A1%8C%E5%9B%9B%E8%BE%B9%E5%BD%A2%EF%BC%9B+%EF%BC%882%EF%BC%89%E5%9C%A8%E6%A3%B1%E9%95%BF%E4%B8%BAa%E7%9A%84%E6%AD%A3%E6%96%B9%E4%BD%93ABCD%EF%BC%8DA1B1C1D1%E4%B8%AD%2CE%E3%80%81F%E5%88%86%E5%88%AB%E4%B8%BADD1%E5%92%8CBB1%E7%9A%84%E4%B8%AD%E7%82%B9%EF%BC%8E%EF%BC%881%EF%BC%89%E8%AF%81%E6%98%8E%EF%BC%9AAEC1F%E6%98%AF%E5%B9%B3%E8%A1%8C%E5%9B%9B%E8%BE%B9%E5%BD%A2)
xmOPB·9Fҭ~)
c
,ʻpA6aDIYO@MLrҧ~>~>|k^Ioov^8s2HP@hRʕ,@Ԋl:
Hہ3Όߪ&pvol'm
P
\ &(w0-QvkktHwi1p&~}k.Fo563@ޛUN'9hHc1fY!}tC1kRO
J@R8Uhh8<*ZyX+ÌIJeM↞E"d
%uDA$Dj㹸@<0X)<(iD ;%b܈C`d5NC^$@q1a?/Y˺ѓB#JHFrhl9 Tڵe5eu%}%&!R]5y5J/ZÓt;5oJAE>;cPt˟8