let 1L be upper-bounded Lattice; for B being Finite_Subset of the carrier of 1L
for f, g being UnOp of the carrier of 1L holds FinMeet (f .: B),g = FinMeet B,(g * f)
let B be Finite_Subset of the carrier of 1L; for f, g being UnOp of the carrier of 1L holds FinMeet (f .: B),g = FinMeet B,(g * f)
let f, g be UnOp of the carrier of 1L; FinMeet (f .: B),g = FinMeet B,(g * f)
set M = the L_meet of 1L;
thus FinMeet (f .: B),g =
the L_meet of 1L $$ (f .: B),g
by LATTICE2:def 4
.=
the L_meet of 1L $$ B,(g * f)
by SETWISEO:44
.=
FinMeet B,(g * f)
by LATTICE2:def 4
; verum