let G be _Graph; for X being set
for E being Subset of (the_Edges_of G)
for H being reverseEdgeDirections of G,X st E is RepEdgeSelection of G holds
E is RepEdgeSelection of H
let X be set ; for E being Subset of (the_Edges_of G)
for H being reverseEdgeDirections of G,X st E is RepEdgeSelection of G holds
E is RepEdgeSelection of H
let E be Subset of (the_Edges_of G); for H being reverseEdgeDirections of G,X st E is RepEdgeSelection of G holds
E is RepEdgeSelection of H
let H be reverseEdgeDirections of G,X; ( E is RepEdgeSelection of G implies E is RepEdgeSelection of H )
assume A1:
E is RepEdgeSelection of G
; E is RepEdgeSelection of H
A2:
E is Subset of (the_Edges_of H)
by GLIB_007:4;
now for v, w, e0 being object st e0 Joins v,w,H holds
ex e being object st
( e Joins v,w,H & e in E & ( for e9 being object st e9 Joins v,w,H & e9 in E holds
e9 = e ) )let v,
w,
e0 be
object ;
( e0 Joins v,w,H implies ex e being object st
( e Joins v,w,H & e in E & ( for e9 being object st e9 Joins v,w,H & e9 in E holds
e9 = e ) ) )assume
e0 Joins v,
w,
H
;
ex e being object st
( e Joins v,w,H & e in E & ( for e9 being object st e9 Joins v,w,H & e9 in E holds
e9 = e ) )then consider e being
object such that A3:
(
e Joins v,
w,
G &
e in E )
and A4:
for
e9 being
object st
e9 Joins v,
w,
G &
e9 in E holds
e9 = e
by A1, GLIB_007:9, GLIB_009:def 5;
take e =
e;
( e Joins v,w,H & e in E & ( for e9 being object st e9 Joins v,w,H & e9 in E holds
e9 = e ) )thus
(
e Joins v,
w,
H &
e in E )
by A3, GLIB_007:9;
for e9 being object st e9 Joins v,w,H & e9 in E holds
e9 = elet e9 be
object ;
( e9 Joins v,w,H & e9 in E implies e9 = e )assume
(
e9 Joins v,
w,
H &
e9 in E )
;
e9 = ehence
e9 = e
by A4, GLIB_007:9;
verum end;
hence
E is RepEdgeSelection of H
by A2, GLIB_009:def 5; verum