let P, Q be non empty strict chain-complete Poset; for f being Element of (ConPoset (P,Q)) st f = min_func (P,Q) holds
f is_<=_than the carrier of (ConPoset (P,Q))
let f be Element of (ConPoset (P,Q)); ( f = min_func (P,Q) implies f is_<=_than the carrier of (ConPoset (P,Q)) )
assume A1:
f = min_func (P,Q)
; f is_<=_than the carrier of (ConPoset (P,Q))
set f1 = min_func (P,Q);
for x being Element of (ConPoset (P,Q)) holds f <= x
proof
let x be
Element of
(ConPoset (P,Q));
f <= x
x in ConFuncs (
P,
Q)
;
then consider x1 being
Element of
Funcs ( the
carrier of
P, the
carrier of
Q)
such that A2:
(
x = x1 & ex
g being
continuous Function of
P,
Q st
g = x1 )
;
consider g being
continuous Function of
P,
Q such that A3:
g = x1
by A2;
for
p being
Element of
P holds
(min_func (P,Q)) . p <= g . p
then
min_func (
P,
Q)
<= g
by YELLOW_2:9;
then
[f,x] in ConRelat (
P,
Q)
by A2, A3, Def7, A1;
hence
f <= x
by ORDERS_2:def 5;
verum
end;
hence
f is_<=_than the carrier of (ConPoset (P,Q))
; verum