let G1, G2 be _Graph; :: thesis: for F being PGraphMapping of G1,G2 st F is total & F is onto holds
G2 .allInducedSG() c= rng ((SG2SGFunc F) | (G1 .allInducedSG()))

let F be PGraphMapping of G1,G2; :: thesis: ( F is total & F is onto implies G2 .allInducedSG() c= rng ((SG2SGFunc F) | (G1 .allInducedSG())) )
assume A1: ( F is total & F is onto ) ; :: thesis: G2 .allInducedSG() c= rng ((SG2SGFunc F) | (G1 .allInducedSG()))
set f = (SG2SGFunc F) | (G1 .allInducedSG());
A2: dom ((SG2SGFunc F) | (G1 .allInducedSG())) = G1 .allInducedSG() by FUNCT_2:def 1;
now :: thesis: for x being object st x in G2 .allInducedSG() holds
x in rng ((SG2SGFunc F) | (G1 .allInducedSG()))
let x be object ; :: thesis: ( x in G2 .allInducedSG() implies x in rng ((SG2SGFunc F) | (G1 .allInducedSG())) )
assume A3: x in G2 .allInducedSG() ; :: thesis: x in rng ((SG2SGFunc F) | (G1 .allInducedSG()))
A4: rng F == G2 by A1, GLIB_010:56;
then x in (rng F) .allInducedSG() by A3, Th49;
then consider V2 being non empty Subset of (the_Vertices_of (rng F)) such that
A5: x = the plain inducedSubgraph of (rng F),V2 ;
reconsider H2 = x as plain inducedSubgraph of (rng F),V2 by A5;
set H1 = the plain inducedSubgraph of G1,((F _V) " (the_Vertices_of H2));
reconsider y = the plain inducedSubgraph of G1,((F _V) " (the_Vertices_of H2)) as object ;
rng (F _V) = the_Vertices_of G2 by A1, GLIB_010:def 12
.= the_Vertices_of (rng F) by A4, GLIB_000:def 34 ;
then A6: (F _V) " V2 <> {} by RELAT_1:139;
the_Vertices_of H2 = V2 by GLIB_000:def 37;
then A7: the plain inducedSubgraph of G1,((F _V) " (the_Vertices_of H2)) in G1 .allInducedSG() by A6;
then A8: y in dom ((SG2SGFunc F) | (G1 .allInducedSG())) by A2;
A9: (SG2SGFunc F) . the plain inducedSubgraph of G1,((F _V) " (the_Vertices_of H2)) = rng (F | the plain inducedSubgraph of G1,((F _V) " (the_Vertices_of H2))) by Def5;
dom (F _E) = the_Edges_of G1 by A1, GLIB_010:def 11;
then G1 .edgesBetween ((F _V) " (the_Vertices_of H2)) c= dom (F _E) ;
then (SG2SGFunc F) . the plain inducedSubgraph of G1,((F _V) " (the_Vertices_of H2)) = H2 by A1, A9, GLIB_009:44, GLIBPRE1:101;
then x = ((SG2SGFunc F) | (G1 .allInducedSG())) . y by A7, FUNCT_1:49;
hence x in rng ((SG2SGFunc F) | (G1 .allInducedSG())) by A8, FUNCT_1:def 3; :: thesis: verum
end;
hence G2 .allInducedSG() c= rng ((SG2SGFunc F) | (G1 .allInducedSG())) by TARSKI:def 3; :: thesis: verum