let Y be non empty set ; :: thesis: for G being Subset of (PARTITIONS Y)
for a being Element of Funcs Y,BOOLEAN
for PA being a_partition of Y holds 'not' (Ex a,PA,G) = All ('not' a),PA,G
let G be Subset of (PARTITIONS Y); :: thesis: for a being Element of Funcs Y,BOOLEAN
for PA being a_partition of Y holds 'not' (Ex a,PA,G) = All ('not' a),PA,G
let a be Element of Funcs Y,BOOLEAN ; :: thesis: for PA being a_partition of Y holds 'not' (Ex a,PA,G) = All ('not' a),PA,G
let PA be a_partition of Y; :: thesis: 'not' (Ex a,PA,G) = All ('not' a),PA,G
A1:
for z being Element of Y holds ('not' (B_SUP a,(CompF PA,G))) . z = (B_INF ('not' a),(CompF PA,G)) . z
proof
let z be
Element of
Y;
:: thesis: ('not' (B_SUP a,(CompF PA,G))) . z = (B_INF ('not' a),(CompF PA,G)) . z
per cases
( ( ( for x being Element of Y st x in EqClass z,(CompF PA,G) holds
('not' a) . x = TRUE ) & ex x being Element of Y st
( x in EqClass z,(CompF PA,G) & a . x = TRUE ) ) or ( ( for x being Element of Y st x in EqClass z,(CompF PA,G) holds
('not' a) . x = TRUE ) & ( for x being Element of Y holds
( not x in EqClass z,(CompF PA,G) or not a . x = TRUE ) ) ) or ( ex x being Element of Y st
( x in EqClass z,(CompF PA,G) & not ('not' a) . x = TRUE ) & ex x being Element of Y st
( x in EqClass z,(CompF PA,G) & a . x = TRUE ) ) or ( ex x being Element of Y st
( x in EqClass z,(CompF PA,G) & not ('not' a) . x = TRUE ) & ( for x being Element of Y holds
( not x in EqClass z,(CompF PA,G) or not a . x = TRUE ) ) ) )
;
suppose A4:
( ( for
x being
Element of
Y st
x in EqClass z,
(CompF PA,G) holds
('not' a) . x = TRUE ) & ( for
x being
Element of
Y holds
( not
x in EqClass z,
(CompF PA,G) or not
a . x = TRUE ) ) )
;
:: thesis: ('not' (B_SUP a,(CompF PA,G))) . z = (B_INF ('not' a),(CompF PA,G)) . zthen
(B_SUP a,(CompF PA,G)) . z = FALSE
by BVFUNC_1:def 20;
then
'not' ((B_SUP a,(CompF PA,G)) . z) = TRUE
by MARGREL1:41;
then
('not' (B_SUP a,(CompF PA,G))) . z = TRUE
by MARGREL1:def 20;
hence
('not' (B_SUP a,(CompF PA,G))) . z = (B_INF ('not' a),(CompF PA,G)) . z
by A4, BVFUNC_1:def 19;
:: thesis: verum end; suppose A5:
( ex
x being
Element of
Y st
(
x in EqClass z,
(CompF PA,G) & not
('not' a) . x = TRUE ) & ex
x being
Element of
Y st
(
x in EqClass z,
(CompF PA,G) &
a . x = TRUE ) )
;
:: thesis: ('not' (B_SUP a,(CompF PA,G))) . z = (B_INF ('not' a),(CompF PA,G)) . zthen A6:
(B_INF ('not' a),(CompF PA,G)) . z = FALSE
by BVFUNC_1:def 19;
(B_SUP a,(CompF PA,G)) . z = TRUE
by A5, BVFUNC_1:def 20;
then
('not' (B_SUP a,(CompF PA,G))) . z = 'not' TRUE
by MARGREL1:def 20;
hence
('not' (B_SUP a,(CompF PA,G))) . z = (B_INF ('not' a),(CompF PA,G)) . z
by A6, MARGREL1:41;
:: thesis: verum end; end;
end;
consider k3 being Function such that
A9:
( 'not' (Ex a,PA,G) = k3 & dom k3 = Y & rng k3 c= BOOLEAN )
by FUNCT_2:def 2;
consider k4 being Function such that
A10:
( All ('not' a),PA,G = k4 & dom k4 = Y & rng k4 c= BOOLEAN )
by FUNCT_2:def 2;
for u being set st u in Y holds
k3 . u = k4 . u
by A1, A9, A10;
hence
'not' (Ex a,PA,G) = All ('not' a),PA,G
by A9, A10, FUNCT_1:9; :: thesis: verum