let 1L be upper-bounded Lattice; :: thesis: for B being Finite_Subset of the carrier of 1L
for b being Element of 1L
for f being UnOp of the carrier of 1L holds FinMeet (B \/ {.b.}),f = (FinMeet B,f) "/\" (f . b)
let B be Finite_Subset of the carrier of 1L; :: thesis: for b being Element of 1L
for f being UnOp of the carrier of 1L holds FinMeet (B \/ {.b.}),f = (FinMeet B,f) "/\" (f . b)
let b be Element of 1L; :: thesis: for f being UnOp of the carrier of 1L holds FinMeet (B \/ {.b.}),f = (FinMeet B,f) "/\" (f . b)
let f be UnOp of the carrier of 1L; :: thesis: FinMeet (B \/ {.b.}),f = (FinMeet B,f) "/\" (f . b)
set M = the L_meet of 1L;
A1:
( the L_meet of 1L is idempotent & the L_meet of 1L is commutative & the L_meet of 1L is associative & the L_meet of 1L is having_a_unity )
by LATTICE2:30, LATTICE2:31, LATTICE2:32, LATTICE2:73;
thus FinMeet (B \/ {.b.}),f =
the L_meet of 1L $$ (B \/ {.b.}),f
by LATTICE2:def 4
.=
(the L_meet of 1L $$ B,f) "/\" (f . b)
by A1, SETWISEO:41
.=
(FinMeet B,f) "/\" (f . b)
by LATTICE2:def 4
; :: thesis: verum