let L be non empty reflexive transitive RelStr ; :: thesis: ( ( for x being Element of L
for N being net of L st N is eventually-directed holds
x "/\" (sup N) = sup ({x} "/\" (rng (netmap N,L))) ) implies L is satisfying_MC )
assume A1:
for x being Element of L
for N being net of L st N is eventually-directed holds
x "/\" (sup N) = sup ({x} "/\" (rng (netmap N,L)))
; :: thesis: L is satisfying_MC
let x be Element of L; :: according to WAYBEL_2:def 6 :: thesis: for b1 being Element of K10(the carrier of L) holds x "/\" ("\/" b1,L) = "\/" ({x} "/\" b1),L
let D be non empty directed Subset of L; :: thesis: x "/\" ("\/" D,L) = "\/" ({x} "/\" D),L
reconsider n = id D as Function of D,the carrier of L by FUNCT_2:9;
set N = NetStr(# D,(the InternalRel of L |_2 D),n #);
D c= D
;
then A2: D =
n .: D
by FUNCT_1:162
.=
rng (netmap NetStr(# D,(the InternalRel of L |_2 D),n #),L)
by FUNCT_2:45
;
A3:
NetStr(# D,(the InternalRel of L |_2 D),n #) is eventually-directed
by WAYBEL_2:20;
A4:
Sup = sup NetStr(# D,(the InternalRel of L |_2 D),n #)
;
thus x "/\" (sup D) =
x "/\" (Sup )
by A2, YELLOW_2:def 5
.=
sup ({x} "/\" D)
by A1, A2, A3, A4
; :: thesis: verum