let X be non empty set ; for R, S being RMembership_Func of X,X st S is transitive & S c= holds
S c=
let R, S be RMembership_Func of X,X; ( S is transitive & S c= implies S c= )
assume that
A1:
S is transitive
and
A2:
S c=
; S c=
for c being Element of [:X,X:] holds (TrCl R) . c <= (TrCl S) . c
proof
set Q =
{ (n iter R) where n is Element of NAT : n > 0 } ;
set RP =
RealPoset [.0,1.];
let c be
Element of
[:X,X:];
(TrCl R) . c <= (TrCl S) . c
for
b being
Element of
(RealPoset [.0,1.]) st
b in pi (
{ (n iter R) where n is Element of NAT : n > 0 } ,
c) holds
b <<= (TrCl S) . c
then
(TrCl S) . c is_>=_than pi (
{ (n iter R) where n is Element of NAT : n > 0 } ,
c)
by LATTICE3:def 9;
then A8:
"\/" (
(pi ( { (n iter R) where n is Element of NAT : n > 0 } ,c)),
(RealPoset [.0,1.]))
<<= (TrCl S) . c
by YELLOW_0:32;
{ (n iter R) where n is Element of NAT : n > 0 } c= the
carrier of
(FuzzyLattice [:X,X:])
then
(TrCl R) . c = "\/" (
(pi ( { (n iter R) where n is Element of NAT : n > 0 } ,c)),
(RealPoset [.0,1.]))
by Th32;
hence
(TrCl R) . c <= (TrCl S) . c
by A8, LFUZZY_0:3;
verum
end;
then
TrCl S c=
;
hence
S c=
by A1, Th38; verum