如图,点E、F分别在AB、CD上,AE/EB=DF/FC,求证: (1)AB/EB=DC/FC; (2)AB/AE=DC/DF.

问题描述:

如图,点E、F分别在AB、CD上,

AE
EB
=
DF
FC
,求证:

(1)
AB
EB
=
DC
FC

(2)
AB
AE
=
DC
DF

证明:(1)∵

AE
EB
=
DF
FC

AE
EB
+1=
DF
FC
+1,
AB
EB
=
DC
FC

(2)∵
AE
EB
=
DF
FC

EB
AE
=
FC
DF

EB
AE
+1=
FC
DF
+1,
EB+AE
AE
=
FC+DF
DF

AB
AE
=
DC
DF