let Y be non empty set ; for G being Subset of (PARTITIONS Y)
for u, a being Function of Y,BOOLEAN
for PA being a_partition of Y st u is_independent_of PA,G holds
All ((u 'or' a),PA,G) = u 'or' (All (a,PA,G))
let G be Subset of (PARTITIONS Y); for u, a being Function of Y,BOOLEAN
for PA being a_partition of Y st u is_independent_of PA,G holds
All ((u 'or' a),PA,G) = u 'or' (All (a,PA,G))
let u, a be Function of Y,BOOLEAN; for PA being a_partition of Y st u is_independent_of PA,G holds
All ((u 'or' a),PA,G) = u 'or' (All (a,PA,G))
let PA be a_partition of Y; ( u is_independent_of PA,G implies All ((u 'or' a),PA,G) = u 'or' (All (a,PA,G)) )
assume Z:
u is_independent_of PA,G
; All ((u 'or' a),PA,G) = u 'or' (All (a,PA,G))
let z be Element of Y; FUNCT_2:def 8 (All ((u 'or' a),PA,G)) . z = (u 'or' (All (a,PA,G))) . z
A6:
(u 'or' (B_INF (a,(CompF (PA,G))))) . z = (u . z) 'or' ((B_INF (a,(CompF (PA,G)))) . z)
by BVFUNC_1:def 4;
per cases
( for x being Element of Y st x in EqClass (z,(CompF (PA,G))) holds
a . x = TRUE or ( ex x being Element of Y st
( x in EqClass (z,(CompF (PA,G))) & not a . x = TRUE ) & ( for x being Element of Y st x in EqClass (z,(CompF (PA,G))) holds
u . x = TRUE ) ) or ( ex x being Element of Y st
( x in EqClass (z,(CompF (PA,G))) & not a . x = TRUE ) & ex x being Element of Y st
( x in EqClass (z,(CompF (PA,G))) & not u . x = TRUE ) ) )
;
suppose A7:
for
x being
Element of
Y st
x in EqClass (
z,
(CompF (PA,G))) holds
a . x = TRUE
;
(All ((u 'or' a),PA,G)) . z = (u 'or' (All (a,PA,G))) . zA8:
for
x being
Element of
Y st
x in EqClass (
z,
(CompF (PA,G))) holds
(u 'or' a) . x = TRUE
(B_INF (a,(CompF (PA,G)))) . z = TRUE
by A7, BVFUNC_1:def 16;
then
(u 'or' (B_INF (a,(CompF (PA,G))))) . z = TRUE
by A6, BINARITH:10;
hence
(All ((u 'or' a),PA,G)) . z = (u 'or' (All (a,PA,G))) . z
by A8, BVFUNC_1:def 16;
verum end; suppose A10:
( ex
x being
Element of
Y st
(
x in EqClass (
z,
(CompF (PA,G))) & not
a . x = TRUE ) & ( for
x being
Element of
Y st
x in EqClass (
z,
(CompF (PA,G))) holds
u . x = TRUE ) )
;
(All ((u 'or' a),PA,G)) . z = (u 'or' (All (a,PA,G))) . zA11:
for
x being
Element of
Y st
x in EqClass (
z,
(CompF (PA,G))) holds
(u 'or' a) . x = TRUE
(u 'or' (B_INF (a,(CompF (PA,G))))) . z = TRUE 'or' ((B_INF (a,(CompF (PA,G)))) . z)
by A6, A10, EQREL_1:def 6;
then
(u 'or' (B_INF (a,(CompF (PA,G))))) . z = TRUE
by BINARITH:10;
hence
(All ((u 'or' a),PA,G)) . z = (u 'or' (All (a,PA,G))) . z
by A11, BVFUNC_1:def 16;
verum end; suppose A13:
( ex
x being
Element of
Y st
(
x in EqClass (
z,
(CompF (PA,G))) & not
a . x = TRUE ) & ex
x being
Element of
Y st
(
x in EqClass (
z,
(CompF (PA,G))) & not
u . x = TRUE ) )
;
(All ((u 'or' a),PA,G)) . z = (u 'or' (All (a,PA,G))) . zthen consider x2 being
Element of
Y such that A14:
x2 in EqClass (
z,
(CompF (PA,G)))
and A15:
u . x2 <> TRUE
;
consider x1 being
Element of
Y such that A16:
x1 in EqClass (
z,
(CompF (PA,G)))
and A17:
a . x1 <> TRUE
by A13;
u . x1 = u . x2
by Z, Def8, A16, A14, BVFUNC_1:def 15;
then A18:
u . x1 = FALSE
by A15, XBOOLEAN:def 3;
A19:
(B_INF (a,(CompF (PA,G)))) . z = FALSE
by A13, BVFUNC_1:def 16;
z in EqClass (
z,
(CompF (PA,G)))
by EQREL_1:def 6;
then A20:
u . x1 = u . z
by Z, Def8, A16, BVFUNC_1:def 15;
a . x1 = FALSE
by A17, XBOOLEAN:def 3;
then
(u 'or' a) . x1 = FALSE 'or' FALSE
by A18, BVFUNC_1:def 4;
hence
(All ((u 'or' a),PA,G)) . z = (u 'or' (All (a,PA,G))) . z
by A6, A19, A16, A18, A20, BVFUNC_1:def 16;
verum end; end;