let A be non empty set ; for L being lower-bounded LATTICE st L is modular holds
for d being BiFunction of A,L st d is symmetric & d is u.t.i. holds
for q being Element of [:A,A, the carrier of L, the carrier of L:] st d . ((q `1_4),(q `2_4)) <= (q `3_4) "\/" (q `4_4) holds
new_bi_fun2 (d,q) is u.t.i.
let L be lower-bounded LATTICE; ( L is modular implies for d being BiFunction of A,L st d is symmetric & d is u.t.i. holds
for q being Element of [:A,A, the carrier of L, the carrier of L:] st d . ((q `1_4),(q `2_4)) <= (q `3_4) "\/" (q `4_4) holds
new_bi_fun2 (d,q) is u.t.i. )
assume A1:
L is modular
; for d being BiFunction of A,L st d is symmetric & d is u.t.i. holds
for q being Element of [:A,A, the carrier of L, the carrier of L:] st d . ((q `1_4),(q `2_4)) <= (q `3_4) "\/" (q `4_4) holds
new_bi_fun2 (d,q) is u.t.i.
reconsider B = {{A},{{A}}} as non empty set ;
let d be BiFunction of A,L; ( d is symmetric & d is u.t.i. implies for q being Element of [:A,A, the carrier of L, the carrier of L:] st d . ((q `1_4),(q `2_4)) <= (q `3_4) "\/" (q `4_4) holds
new_bi_fun2 (d,q) is u.t.i. )
assume that
A2:
d is symmetric
and
A3:
d is u.t.i.
; for q being Element of [:A,A, the carrier of L, the carrier of L:] st d . ((q `1_4),(q `2_4)) <= (q `3_4) "\/" (q `4_4) holds
new_bi_fun2 (d,q) is u.t.i.
let q be Element of [:A,A, the carrier of L, the carrier of L:]; ( d . ((q `1_4),(q `2_4)) <= (q `3_4) "\/" (q `4_4) implies new_bi_fun2 (d,q) is u.t.i. )
set x = q `1_4 ;
set y = q `2_4 ;
set a = q `3_4 ;
set b = q `4_4 ;
set f = new_bi_fun2 (d,q);
reconsider a = q `3_4 , b = q `4_4 as Element of L ;
A4:
for p, q, u being Element of new_set2 A st p in A & q in A & u in B holds
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
proof
let p,
q,
u be
Element of
new_set2 A;
( p in A & q in A & u in B implies (new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u)) )
assume A5:
(
p in A &
q in A &
u in B )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
per cases
( ( p in A & q in A & u = {A} ) or ( p in A & q in A & u = {{A}} ) )
by A5, TARSKI:def 2;
suppose A6:
(
p in A &
q in A &
u = {A} )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))then reconsider p9 =
p,
q9 =
q as
Element of
A ;
A7:
(new_bi_fun2 (d,q)) . (
p,
q)
= d . (
p9,
q9)
by Def4;
d . (
p9,
(q `1_4))
<= (d . (p9,q9)) "\/" (d . (q9,(q `1_4)))
by A3;
then A8:
(d . (p9,(q `1_4))) "\/" a <= ((d . (p9,q9)) "\/" (d . (q9,(q `1_4)))) "\/" a
by WAYBEL_1:2;
(
(new_bi_fun2 (d,q)) . (
p,
u)
= (d . (p9,(q `1_4))) "\/" a &
(new_bi_fun2 (d,q)) . (
q,
u)
= (d . (q9,(q `1_4))) "\/" a )
by A6, Def4;
hence
(new_bi_fun2 (d,q)) . (
p,
u)
<= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A7, A8, LATTICE3:14;
verum end; suppose A9:
(
p in A &
q in A &
u = {{A}} )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))then reconsider p9 =
p,
q9 =
q as
Element of
A ;
A10:
(new_bi_fun2 (d,q)) . (
p,
q)
= d . (
p9,
q9)
by Def4;
d . (
p9,
(q `2_4))
<= (d . (p9,q9)) "\/" (d . (q9,(q `2_4)))
by A3;
then A11:
(d . (p9,(q `2_4))) "\/" a <= ((d . (p9,q9)) "\/" (d . (q9,(q `2_4)))) "\/" a
by WAYBEL_1:2;
(
(new_bi_fun2 (d,q)) . (
p,
u)
= (d . (p9,(q `2_4))) "\/" a &
(new_bi_fun2 (d,q)) . (
q,
u)
= (d . (q9,(q `2_4))) "\/" a )
by A9, Def4;
hence
(new_bi_fun2 (d,q)) . (
p,
u)
<= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A10, A11, LATTICE3:14;
verum end; end;
end;
assume A12:
d . ((q `1_4),(q `2_4)) <= (q `3_4) "\/" (q `4_4)
; new_bi_fun2 (d,q) is u.t.i.
A13:
for p, q, u being Element of new_set2 A st p in A & q in B & u in B holds
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
proof
let p,
q,
u be
Element of
new_set2 A;
( p in A & q in B & u in B implies (new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u)) )
assume A14:
(
p in A &
q in B &
u in B )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
per cases
( ( p in A & q = {A} & u = {A} ) or ( p in A & q = {A} & u = {{A}} ) or ( p in A & q = {{A}} & u = {A} ) or ( p in A & q = {{A}} & u = {{A}} ) )
by A14, TARSKI:def 2;
suppose A15:
(
p in A &
q = {A} &
u = {A} )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))then ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u)) =
(Bottom L) "\/" ((new_bi_fun2 (d,q)) . (p,q))
by Def4
.=
(new_bi_fun2 (d,q)) . (
p,
q)
by WAYBEL_1:3
;
hence
(new_bi_fun2 (d,q)) . (
p,
u)
<= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A15;
verum end; suppose A16:
(
p in A &
q = {A} &
u = {{A}} )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))then reconsider p9 =
p as
Element of
A ;
a <= a "\/" (d . ((q `1_4),(q `2_4)))
by YELLOW_0:22;
then A17:
a "\/" (((d . ((q `1_4),(q `2_4))) "\/" a) "/\" b) = (a "\/" b) "/\" (a "\/" (d . ((q `1_4),(q `2_4))))
by A1;
d . (
p9,
(q `2_4))
<= (d . (p9,(q `1_4))) "\/" (d . ((q `1_4),(q `2_4)))
by A3;
then A18:
(d . (p9,(q `2_4))) "\/" a <= ((d . (p9,(q `1_4))) "\/" (d . ((q `1_4),(q `2_4)))) "\/" a
by YELLOW_5:7;
a <= a
;
then
(d . ((q `1_4),(q `2_4))) "\/" a <= (a "\/" b) "\/" a
by A12, YELLOW_3:3;
then
((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((d . ((q `1_4),(q `2_4))) "\/" a) <= ((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((a "\/" b) "\/" a)
by YELLOW_5:6;
then A19:
(
(d . ((q `1_4),(q `2_4))) "\/" a = ((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((d . ((q `1_4),(q `2_4))) "\/" a) &
(d . (p9,(q `1_4))) "\/" (((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((d . ((q `1_4),(q `2_4))) "\/" a)) <= (d . (p9,(q `1_4))) "\/" (((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((a "\/" b) "\/" a)) )
by WAYBEL_1:2, YELLOW_5:2;
(
(new_bi_fun2 (d,q)) . (
p,
q)
= (d . (p9,(q `1_4))) "\/" a &
(new_bi_fun2 (d,q)) . (
q,
u)
= ((d . ((q `1_4),(q `2_4))) "\/" a) "/\" b )
by A16, Def4;
then ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u)) =
(d . (p9,(q `1_4))) "\/" ((a "\/" b) "/\" (a "\/" (d . ((q `1_4),(q `2_4)))))
by A17, LATTICE3:14
.=
(d . (p9,(q `1_4))) "\/" (((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((a "\/" a) "\/" b))
by YELLOW_5:1
.=
(d . (p9,(q `1_4))) "\/" (((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((a "\/" b) "\/" a))
by LATTICE3:14
;
then
((d . (p9,(q `1_4))) "\/" (d . ((q `1_4),(q `2_4)))) "\/" a <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A19, LATTICE3:14;
then
(d . (p9,(q `2_4))) "\/" a <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A18, ORDERS_2:3;
hence
(new_bi_fun2 (d,q)) . (
p,
u)
<= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A16, Def4;
verum end; suppose A20:
(
p in A &
q = {{A}} &
u = {A} )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))then reconsider p9 =
p as
Element of
A ;
a <= a "\/" (d . ((q `1_4),(q `2_4)))
by YELLOW_0:22;
then A21:
a "\/" (((d . ((q `1_4),(q `2_4))) "\/" a) "/\" b) = (a "\/" b) "/\" (a "\/" (d . ((q `1_4),(q `2_4))))
by A1;
a <= a
;
then
(d . ((q `1_4),(q `2_4))) "\/" a <= (a "\/" b) "\/" a
by A12, YELLOW_3:3;
then
((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((d . ((q `1_4),(q `2_4))) "\/" a) <= ((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((a "\/" b) "\/" a)
by YELLOW_5:6;
then A22:
(
(d . ((q `1_4),(q `2_4))) "\/" a = ((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((d . ((q `1_4),(q `2_4))) "\/" a) &
(d . (p9,(q `2_4))) "\/" (((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((d . ((q `1_4),(q `2_4))) "\/" a)) <= (d . (p9,(q `2_4))) "\/" (((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((a "\/" b) "\/" a)) )
by WAYBEL_1:2, YELLOW_5:2;
d . (
(q `2_4),
(q `1_4))
= d . (
(q `1_4),
(q `2_4))
by A2;
then
d . (
p9,
(q `1_4))
<= (d . (p9,(q `2_4))) "\/" (d . ((q `1_4),(q `2_4)))
by A3;
then A23:
(d . (p9,(q `1_4))) "\/" a <= ((d . (p9,(q `2_4))) "\/" (d . ((q `1_4),(q `2_4)))) "\/" a
by YELLOW_5:7;
(
(new_bi_fun2 (d,q)) . (
p,
q)
= (d . (p9,(q `2_4))) "\/" a &
(new_bi_fun2 (d,q)) . (
q,
u)
= ((d . ((q `1_4),(q `2_4))) "\/" a) "/\" b )
by A20, Def4;
then ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u)) =
(d . (p9,(q `2_4))) "\/" ((a "\/" b) "/\" (a "\/" (d . ((q `1_4),(q `2_4)))))
by A21, LATTICE3:14
.=
(d . (p9,(q `2_4))) "\/" (((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((a "\/" a) "\/" b))
by YELLOW_5:1
.=
(d . (p9,(q `2_4))) "\/" (((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((a "\/" b) "\/" a))
by LATTICE3:14
;
then
((d . (p9,(q `2_4))) "\/" (d . ((q `1_4),(q `2_4)))) "\/" a <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A22, LATTICE3:14;
then
(d . (p9,(q `1_4))) "\/" a <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A23, ORDERS_2:3;
hence
(new_bi_fun2 (d,q)) . (
p,
u)
<= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A20, Def4;
verum end; suppose A24:
(
p in A &
q = {{A}} &
u = {{A}} )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))then ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u)) =
(Bottom L) "\/" ((new_bi_fun2 (d,q)) . (p,q))
by Def4
.=
(new_bi_fun2 (d,q)) . (
p,
q)
by WAYBEL_1:3
;
hence
(new_bi_fun2 (d,q)) . (
p,
u)
<= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A24;
verum end; end;
end;
A25:
for p, q, u being Element of new_set2 A st p in B & q in A & u in B holds
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
proof
let p,
q,
u be
Element of
new_set2 A;
( p in B & q in A & u in B implies (new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u)) )
assume A26:
(
p in B &
q in A &
u in B )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
per cases
( ( q in A & p = {A} & u = {A} ) or ( q in A & p = {A} & u = {{A}} ) or ( q in A & p = {{A}} & u = {A} ) or ( q in A & p = {{A}} & u = {{A}} ) )
by A26, TARSKI:def 2;
suppose A27:
(
q in A &
p = {A} &
u = {{A}} )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))then reconsider q9 =
q as
Element of
A ;
d . (
q9,
(q `1_4))
= d . (
(q `1_4),
q9)
by A2;
then A28:
d . (
(q `1_4),
(q `2_4))
<= (d . (q9,(q `1_4))) "\/" (d . (q9,(q `2_4)))
by A3;
(new_bi_fun2 (d,q)) . (
p,
q)
= (d . (q9,(q `1_4))) "\/" a
by A27, Def4;
then ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u)) =
((d . (q9,(q `1_4))) "\/" a) "\/" ((d . (q9,(q `2_4))) "\/" a)
by A27, Def4
.=
((d . (q9,(q `1_4))) "\/" ((d . (q9,(q `2_4))) "\/" a)) "\/" a
by LATTICE3:14
.=
(((d . (q9,(q `1_4))) "\/" (d . (q9,(q `2_4)))) "\/" a) "\/" a
by LATTICE3:14
.=
((d . (q9,(q `1_4))) "\/" (d . (q9,(q `2_4)))) "\/" (a "\/" a)
by LATTICE3:14
.=
((d . (q9,(q `1_4))) "\/" (d . (q9,(q `2_4)))) "\/" a
by YELLOW_5:1
;
then A29:
(d . ((q `1_4),(q `2_4))) "\/" a <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A28, YELLOW_5:7;
A30:
((d . ((q `1_4),(q `2_4))) "\/" a) "/\" b <= (d . ((q `1_4),(q `2_4))) "\/" a
by YELLOW_0:23;
(new_bi_fun2 (d,q)) . (
p,
u)
= ((d . ((q `1_4),(q `2_4))) "\/" a) "/\" b
by A27, Def4;
hence
(new_bi_fun2 (d,q)) . (
p,
u)
<= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A29, A30, ORDERS_2:3;
verum end; suppose A31:
(
q in A &
p = {{A}} &
u = {A} )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))then reconsider q9 =
q as
Element of
A ;
d . (
q9,
(q `1_4))
= d . (
(q `1_4),
q9)
by A2;
then A32:
d . (
(q `1_4),
(q `2_4))
<= (d . (q9,(q `1_4))) "\/" (d . (q9,(q `2_4)))
by A3;
(new_bi_fun2 (d,q)) . (
p,
q)
= (d . (q9,(q `2_4))) "\/" a
by A31, Def4;
then ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u)) =
((d . (q9,(q `1_4))) "\/" a) "\/" ((d . (q9,(q `2_4))) "\/" a)
by A31, Def4
.=
((d . (q9,(q `1_4))) "\/" ((d . (q9,(q `2_4))) "\/" a)) "\/" a
by LATTICE3:14
.=
(((d . (q9,(q `1_4))) "\/" (d . (q9,(q `2_4)))) "\/" a) "\/" a
by LATTICE3:14
.=
((d . (q9,(q `1_4))) "\/" (d . (q9,(q `2_4)))) "\/" (a "\/" a)
by LATTICE3:14
.=
((d . (q9,(q `1_4))) "\/" (d . (q9,(q `2_4)))) "\/" a
by YELLOW_5:1
;
then A33:
(d . ((q `1_4),(q `2_4))) "\/" a <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A32, YELLOW_5:7;
A34:
((d . ((q `1_4),(q `2_4))) "\/" a) "/\" b <= (d . ((q `1_4),(q `2_4))) "\/" a
by YELLOW_0:23;
(new_bi_fun2 (d,q)) . (
p,
u)
= ((d . ((q `1_4),(q `2_4))) "\/" a) "/\" b
by A31, Def4;
hence
(new_bi_fun2 (d,q)) . (
p,
u)
<= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A33, A34, ORDERS_2:3;
verum end; end;
end;
A35:
for p, q, u being Element of new_set2 A st p in B & q in B & u in B holds
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
proof
let p,
q,
u be
Element of
new_set2 A;
( p in B & q in B & u in B implies (new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u)) )
assume A36:
(
p in B &
q in B &
u in B )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
per cases
( ( p = {A} & q = {A} & u = {A} ) or ( p = {A} & q = {A} & u = {{A}} ) or ( p = {A} & q = {{A}} & u = {A} ) or ( p = {A} & q = {{A}} & u = {{A}} ) or ( p = {{A}} & q = {A} & u = {A} ) or ( p = {{A}} & q = {A} & u = {{A}} ) or ( p = {{A}} & q = {{A}} & u = {A} ) or ( p = {{A}} & q = {{A}} & u = {{A}} ) )
by A36, TARSKI:def 2;
suppose A37:
(
p = {A} &
q = {A} &
u = {A} )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
Bottom L <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by YELLOW_0:44;
hence
(new_bi_fun2 (d,q)) . (
p,
u)
<= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A37, Def4;
verum end; suppose A38:
(
p = {A} &
q = {A} &
u = {{A}} )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))then ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u)) =
(Bottom L) "\/" ((new_bi_fun2 (d,q)) . (p,u))
by Def4
.=
(Bottom L) "\/" (((d . ((q `1_4),(q `2_4))) "\/" a) "/\" b)
by A38, Def4
.=
((d . ((q `1_4),(q `2_4))) "\/" a) "/\" b
by WAYBEL_1:3
;
hence
(new_bi_fun2 (d,q)) . (
p,
u)
<= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A38, Def4;
verum end; suppose A39:
(
p = {A} &
q = {{A}} &
u = {A} )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
Bottom L <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by YELLOW_0:44;
hence
(new_bi_fun2 (d,q)) . (
p,
u)
<= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A39, Def4;
verum end; suppose A40:
(
p = {A} &
q = {{A}} &
u = {{A}} )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))then ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u)) =
(((d . ((q `1_4),(q `2_4))) "\/" a) "/\" b) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by Def4
.=
(Bottom L) "\/" (((d . ((q `1_4),(q `2_4))) "\/" a) "/\" b)
by A40, Def4
.=
((d . ((q `1_4),(q `2_4))) "\/" a) "/\" b
by WAYBEL_1:3
;
hence
(new_bi_fun2 (d,q)) . (
p,
u)
<= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A40, Def4;
verum end; suppose A41:
(
p = {{A}} &
q = {A} &
u = {A} )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))then ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u)) =
(((d . ((q `1_4),(q `2_4))) "\/" a) "/\" b) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by Def4
.=
(Bottom L) "\/" (((d . ((q `1_4),(q `2_4))) "\/" a) "/\" b)
by A41, Def4
.=
((d . ((q `1_4),(q `2_4))) "\/" a) "/\" b
by WAYBEL_1:3
.=
(new_bi_fun2 (d,q)) . (
p,
q)
by A41, Def4
;
hence
(new_bi_fun2 (d,q)) . (
p,
u)
<= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A41;
verum end; suppose A42:
(
p = {{A}} &
q = {A} &
u = {{A}} )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
Bottom L <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by YELLOW_0:44;
hence
(new_bi_fun2 (d,q)) . (
p,
u)
<= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A42, Def4;
verum end; suppose A43:
(
p = {{A}} &
q = {{A}} &
u = {A} )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))then ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u)) =
(Bottom L) "\/" ((new_bi_fun2 (d,q)) . (p,u))
by Def4
.=
(Bottom L) "\/" (((d . ((q `1_4),(q `2_4))) "\/" a) "/\" b)
by A43, Def4
.=
((d . ((q `1_4),(q `2_4))) "\/" a) "/\" b
by WAYBEL_1:3
;
hence
(new_bi_fun2 (d,q)) . (
p,
u)
<= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A43, Def4;
verum end; suppose A44:
(
p = {{A}} &
q = {{A}} &
u = {{A}} )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
Bottom L <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by YELLOW_0:44;
hence
(new_bi_fun2 (d,q)) . (
p,
u)
<= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A44, Def4;
verum end; end;
end;
A45:
for p, q, u being Element of new_set2 A st p in B & q in B & u in A holds
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
proof
let p,
q,
u be
Element of
new_set2 A;
( p in B & q in B & u in A implies (new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u)) )
assume A46:
(
p in B &
q in B &
u in A )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
per cases
( ( u in A & q = {A} & p = {A} ) or ( u in A & q = {A} & p = {{A}} ) or ( u in A & q = {{A}} & p = {A} ) or ( u in A & q = {{A}} & p = {{A}} ) )
by A46, TARSKI:def 2;
suppose A47:
(
u in A &
q = {A} &
p = {A} )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))then ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u)) =
(Bottom L) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by Def4
.=
(new_bi_fun2 (d,q)) . (
p,
u)
by A47, WAYBEL_1:3
;
hence
(new_bi_fun2 (d,q)) . (
p,
u)
<= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
;
verum end; suppose A48:
(
u in A &
q = {A} &
p = {{A}} )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))then reconsider u9 =
u as
Element of
A ;
a <= a "\/" (d . ((q `1_4),(q `2_4)))
by YELLOW_0:22;
then A49:
a "\/" (((d . ((q `1_4),(q `2_4))) "\/" a) "/\" b) = (a "\/" b) "/\" (a "\/" (d . ((q `1_4),(q `2_4))))
by A1;
d . (
u9,
(q `2_4))
<= (d . (u9,(q `1_4))) "\/" (d . ((q `1_4),(q `2_4)))
by A3;
then A50:
(d . (u9,(q `2_4))) "\/" a <= ((d . (u9,(q `1_4))) "\/" (d . ((q `1_4),(q `2_4)))) "\/" a
by YELLOW_5:7;
a <= a
;
then
(d . ((q `1_4),(q `2_4))) "\/" a <= (a "\/" b) "\/" a
by A12, YELLOW_3:3;
then
((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((d . ((q `1_4),(q `2_4))) "\/" a) <= ((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((a "\/" b) "\/" a)
by YELLOW_5:6;
then A51:
(
(d . ((q `1_4),(q `2_4))) "\/" a = ((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((d . ((q `1_4),(q `2_4))) "\/" a) &
(d . (u9,(q `1_4))) "\/" (((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((d . ((q `1_4),(q `2_4))) "\/" a)) <= (d . (u9,(q `1_4))) "\/" (((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((a "\/" b) "\/" a)) )
by WAYBEL_1:2, YELLOW_5:2;
(
(new_bi_fun2 (d,q)) . (
p,
q)
= ((d . ((q `1_4),(q `2_4))) "\/" a) "/\" b &
(new_bi_fun2 (d,q)) . (
q,
u)
= (d . (u9,(q `1_4))) "\/" a )
by A48, Def4;
then ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u)) =
(d . (u9,(q `1_4))) "\/" ((a "\/" b) "/\" (a "\/" (d . ((q `1_4),(q `2_4)))))
by A49, LATTICE3:14
.=
(d . (u9,(q `1_4))) "\/" (((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((a "\/" a) "\/" b))
by YELLOW_5:1
.=
(d . (u9,(q `1_4))) "\/" (((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((a "\/" b) "\/" a))
by LATTICE3:14
;
then
((d . (u9,(q `1_4))) "\/" (d . ((q `1_4),(q `2_4)))) "\/" a <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A51, LATTICE3:14;
then
(d . (u9,(q `2_4))) "\/" a <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A50, ORDERS_2:3;
hence
(new_bi_fun2 (d,q)) . (
p,
u)
<= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A48, Def4;
verum end; suppose A52:
(
u in A &
q = {{A}} &
p = {A} )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))then reconsider u9 =
u as
Element of
A ;
a <= a "\/" (d . ((q `1_4),(q `2_4)))
by YELLOW_0:22;
then A53:
a "\/" (((d . ((q `1_4),(q `2_4))) "\/" a) "/\" b) = (a "\/" b) "/\" (a "\/" (d . ((q `1_4),(q `2_4))))
by A1;
a <= a
;
then
(d . ((q `1_4),(q `2_4))) "\/" a <= (a "\/" b) "\/" a
by A12, YELLOW_3:3;
then
((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((d . ((q `1_4),(q `2_4))) "\/" a) <= ((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((a "\/" b) "\/" a)
by YELLOW_5:6;
then A54:
(
(d . ((q `1_4),(q `2_4))) "\/" a = ((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((d . ((q `1_4),(q `2_4))) "\/" a) &
(d . (u9,(q `2_4))) "\/" (((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((d . ((q `1_4),(q `2_4))) "\/" a)) <= (d . (u9,(q `2_4))) "\/" (((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((a "\/" b) "\/" a)) )
by WAYBEL_1:2, YELLOW_5:2;
d . (
(q `2_4),
(q `1_4))
= d . (
(q `1_4),
(q `2_4))
by A2;
then
d . (
u9,
(q `1_4))
<= (d . (u9,(q `2_4))) "\/" (d . ((q `1_4),(q `2_4)))
by A3;
then A55:
(d . (u9,(q `1_4))) "\/" a <= ((d . (u9,(q `2_4))) "\/" (d . ((q `1_4),(q `2_4)))) "\/" a
by YELLOW_5:7;
(
(new_bi_fun2 (d,q)) . (
p,
q)
= ((d . ((q `1_4),(q `2_4))) "\/" a) "/\" b &
(new_bi_fun2 (d,q)) . (
q,
u)
= (d . (u9,(q `2_4))) "\/" a )
by A52, Def4;
then ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u)) =
(d . (u9,(q `2_4))) "\/" ((a "\/" b) "/\" (a "\/" (d . ((q `1_4),(q `2_4)))))
by A53, LATTICE3:14
.=
(d . (u9,(q `2_4))) "\/" (((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((a "\/" a) "\/" b))
by YELLOW_5:1
.=
(d . (u9,(q `2_4))) "\/" (((d . ((q `1_4),(q `2_4))) "\/" a) "/\" ((a "\/" b) "\/" a))
by LATTICE3:14
;
then
((d . (u9,(q `2_4))) "\/" (d . ((q `1_4),(q `2_4)))) "\/" a <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A54, LATTICE3:14;
then
(d . (u9,(q `1_4))) "\/" a <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A55, ORDERS_2:3;
hence
(new_bi_fun2 (d,q)) . (
p,
u)
<= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A52, Def4;
verum end; suppose A56:
(
u in A &
q = {{A}} &
p = {{A}} )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))then ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u)) =
(Bottom L) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by Def4
.=
(new_bi_fun2 (d,q)) . (
p,
u)
by A56, WAYBEL_1:3
;
hence
(new_bi_fun2 (d,q)) . (
p,
u)
<= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
;
verum end; end;
end;
A57:
for p, q, u being Element of new_set2 A st p in B & q in A & u in A holds
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
proof
let p,
q,
u be
Element of
new_set2 A;
( p in B & q in A & u in A implies (new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u)) )
assume that A58:
p in B
and A59:
(
q in A &
u in A )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
reconsider q9 =
q,
u9 =
u as
Element of
A by A59;
per cases
( ( p = {A} & q in A & u in A ) or ( p = {{A}} & q in A & u in A ) )
by A58, A59, TARSKI:def 2;
suppose A60:
(
p = {A} &
q in A &
u in A )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
d . (
u9,
(q `1_4))
<= (d . (u9,q9)) "\/" (d . (q9,(q `1_4)))
by A3;
then
d . (
u9,
(q `1_4))
<= (d . (q9,u9)) "\/" (d . (q9,(q `1_4)))
by A2;
then
(d . (u9,(q `1_4))) "\/" a <= ((d . (q9,(q `1_4))) "\/" (d . (q9,u9))) "\/" a
by WAYBEL_1:2;
then A61:
(d . (u9,(q `1_4))) "\/" a <= ((d . (q9,(q `1_4))) "\/" a) "\/" (d . (q9,u9))
by LATTICE3:14;
A62:
(new_bi_fun2 (d,q)) . (
q,
u)
= d . (
q9,
u9)
by Def4;
(new_bi_fun2 (d,q)) . (
p,
q)
= (d . (q9,(q `1_4))) "\/" a
by A60, Def4;
hence
(new_bi_fun2 (d,q)) . (
p,
u)
<= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A60, A62, A61, Def4;
verum end; suppose A63:
(
p = {{A}} &
q in A &
u in A )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
d . (
u9,
(q `2_4))
<= (d . (u9,q9)) "\/" (d . (q9,(q `2_4)))
by A3;
then
d . (
u9,
(q `2_4))
<= (d . (q9,u9)) "\/" (d . (q9,(q `2_4)))
by A2;
then
(d . (u9,(q `2_4))) "\/" a <= ((d . (q9,(q `2_4))) "\/" (d . (q9,u9))) "\/" a
by WAYBEL_1:2;
then A64:
(d . (u9,(q `2_4))) "\/" a <= ((d . (q9,(q `2_4))) "\/" a) "\/" (d . (q9,u9))
by LATTICE3:14;
A65:
(new_bi_fun2 (d,q)) . (
q,
u)
= d . (
q9,
u9)
by Def4;
(new_bi_fun2 (d,q)) . (
p,
q)
= (d . (q9,(q `2_4))) "\/" a
by A63, Def4;
hence
(new_bi_fun2 (d,q)) . (
p,
u)
<= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A63, A65, A64, Def4;
verum end; end;
end;
A66:
for p, q, u being Element of new_set2 A st p in A & q in B & u in A holds
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
proof
let p,
q,
u be
Element of
new_set2 A;
( p in A & q in B & u in A implies (new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u)) )
assume A67:
(
p in A &
q in B &
u in A )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
per cases
( ( p in A & u in A & q = {A} ) or ( p in A & u in A & q = {{A}} ) )
by A67, TARSKI:def 2;
suppose A68:
(
p in A &
u in A &
q = {A} )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))then reconsider p9 =
p,
u9 =
u as
Element of
A ;
d . (
p9,
u9)
<= (d . (p9,(q `1_4))) "\/" (d . ((q `1_4),u9))
by A3;
then A69:
(
(d . (p9,(q `1_4))) "\/" (d . (u9,(q `1_4))) <= ((d . (p9,(q `1_4))) "\/" (d . (u9,(q `1_4)))) "\/" a &
d . (
p9,
u9)
<= (d . (p9,(q `1_4))) "\/" (d . (u9,(q `1_4))) )
by A2, YELLOW_0:22;
((d . (p9,(q `1_4))) "\/" (d . (u9,(q `1_4)))) "\/" a =
(d . (p9,(q `1_4))) "\/" ((d . (u9,(q `1_4))) "\/" a)
by LATTICE3:14
.=
(d . (p9,(q `1_4))) "\/" ((d . (u9,(q `1_4))) "\/" (a "\/" a))
by YELLOW_5:1
.=
(d . (p9,(q `1_4))) "\/" (((d . (u9,(q `1_4))) "\/" a) "\/" a)
by LATTICE3:14
.=
((d . (p9,(q `1_4))) "\/" a) "\/" ((d . (u9,(q `1_4))) "\/" a)
by LATTICE3:14
;
then A70:
d . (
p9,
u9)
<= ((d . (p9,(q `1_4))) "\/" a) "\/" ((d . (u9,(q `1_4))) "\/" a)
by A69, ORDERS_2:3;
(
(new_bi_fun2 (d,q)) . (
p,
q)
= (d . (p9,(q `1_4))) "\/" a &
(new_bi_fun2 (d,q)) . (
q,
u)
= (d . (u9,(q `1_4))) "\/" a )
by A68, Def4;
hence
(new_bi_fun2 (d,q)) . (
p,
u)
<= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A70, Def4;
verum end; suppose A71:
(
p in A &
u in A &
q = {{A}} )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))then reconsider p9 =
p,
u9 =
u as
Element of
A ;
d . (
p9,
u9)
<= (d . (p9,(q `2_4))) "\/" (d . ((q `2_4),u9))
by A3;
then A72:
(
(d . (p9,(q `2_4))) "\/" (d . (u9,(q `2_4))) <= ((d . (p9,(q `2_4))) "\/" (d . (u9,(q `2_4)))) "\/" a &
d . (
p9,
u9)
<= (d . (p9,(q `2_4))) "\/" (d . (u9,(q `2_4))) )
by A2, YELLOW_0:22;
((d . (p9,(q `2_4))) "\/" (d . (u9,(q `2_4)))) "\/" a =
(d . (p9,(q `2_4))) "\/" ((d . (u9,(q `2_4))) "\/" a)
by LATTICE3:14
.=
(d . (p9,(q `2_4))) "\/" ((d . (u9,(q `2_4))) "\/" (a "\/" a))
by YELLOW_5:1
.=
(d . (p9,(q `2_4))) "\/" (((d . (u9,(q `2_4))) "\/" a) "\/" a)
by LATTICE3:14
.=
((d . (p9,(q `2_4))) "\/" a) "\/" ((d . (u9,(q `2_4))) "\/" a)
by LATTICE3:14
;
then A73:
d . (
p9,
u9)
<= ((d . (p9,(q `2_4))) "\/" a) "\/" ((d . (u9,(q `2_4))) "\/" a)
by A72, ORDERS_2:3;
(
(new_bi_fun2 (d,q)) . (
p,
q)
= (d . (p9,(q `2_4))) "\/" a &
(new_bi_fun2 (d,q)) . (
q,
u)
= (d . (u9,(q `2_4))) "\/" a )
by A71, Def4;
hence
(new_bi_fun2 (d,q)) . (
p,
u)
<= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A73, Def4;
verum end; end;
end;
A74:
for p, q, u being Element of new_set2 A st p in A & q in A & u in A holds
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
proof
let p,
q,
u be
Element of
new_set2 A;
( p in A & q in A & u in A implies (new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u)) )
assume
(
p in A &
q in A &
u in A )
;
(new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
then reconsider p9 =
p,
q9 =
q,
u9 =
u as
Element of
A ;
A75:
(new_bi_fun2 (d,q)) . (
q,
u)
= d . (
q9,
u9)
by Def4;
(
(new_bi_fun2 (d,q)) . (
p,
u)
= d . (
p9,
u9) &
(new_bi_fun2 (d,q)) . (
p,
q)
= d . (
p9,
q9) )
by Def4;
hence
(new_bi_fun2 (d,q)) . (
p,
u)
<= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
by A3, A75;
verum
end;
for p, q, u being Element of new_set2 A holds (new_bi_fun2 (d,q)) . (p,u) <= ((new_bi_fun2 (d,q)) . (p,q)) "\/" ((new_bi_fun2 (d,q)) . (q,u))
hence
new_bi_fun2 (d,q) is u.t.i.
; verum