let A be non empty set ; :: thesis: for B being Finite_Subset of A
for L being 1_Lattice
for f being Function of A,the carrier of L
for u being Element of L st ( for x being Element of A st x in B holds
u [= f . x ) holds
u [= FinMeet B,f
let B be Finite_Subset of A; :: thesis: for L being 1_Lattice
for f being Function of A,the carrier of L
for u being Element of L st ( for x being Element of A st x in B holds
u [= f . x ) holds
u [= FinMeet B,f
let L be 1_Lattice; :: thesis: for f being Function of A,the carrier of L
for u being Element of L st ( for x being Element of A st x in B holds
u [= f . x ) holds
u [= FinMeet B,f
let f be Function of A,the carrier of L; :: thesis: for u being Element of L st ( for x being Element of A st x in B holds
u [= f . x ) holds
u [= FinMeet B,f
let u be Element of L; :: thesis: ( ( for x being Element of A st x in B holds
u [= f . x ) implies u [= FinMeet B,f )
assume A1:
for x being Element of A st x in B holds
u [= f . x
; :: thesis: u [= FinMeet B,f
reconsider f' = f as Function of A,the carrier of (L .: ) ;
reconsider u' = u as Element of (L .: ) ;
A2:
L .: is 0_Lattice
by Th64;
for x being Element of A st x in B holds
f' . x [= u'
by A1, Th53;
then
FinJoin B,f' [= u'
by A2, Th70;
hence
u [= FinMeet B,f
by Th54; :: thesis: verum