let UA be Universal_Algebra; for h being Function st dom h = UAAut UA & ( for x being set st x in UAAut UA holds
h . x = 0 .--> x ) holds
rng h = MSAAut (MSAlg UA)
let h be Function; ( dom h = UAAut UA & ( for x being set st x in UAAut UA holds
h . x = 0 .--> x ) implies rng h = MSAAut (MSAlg UA) )
assume that
A1:
dom h = UAAut UA
and
A2:
for x being set st x in UAAut UA holds
h . x = 0 .--> x
; rng h = MSAAut (MSAlg UA)
thus
rng h c= MSAAut (MSAlg UA)
XBOOLE_0:def 10 MSAAut (MSAlg UA) c= rng hproof
let x be
set ;
TARSKI:def 3 ( not x in rng h or x in MSAAut (MSAlg UA) )
assume
x in rng h
;
x in MSAAut (MSAlg UA)
then consider q being
set such that A3:
q in dom h
and A4:
x = h . q
by FUNCT_1:def 5;
consider q9 being
Element of
UAAut UA such that A5:
q9 = q
by A1, A3;
(
x = 0 .--> q &
0 .--> q is
ManySortedFunction of
(MSAlg UA),
(MSAlg UA) )
by A1, A2, A3, A4, Th39;
then consider d being
ManySortedFunction of
(MSAlg UA),
(MSAlg UA) such that A6:
d = x
;
q9 is_isomorphism UA,
UA
by Def1;
then A7:
MSAlg q9 is_isomorphism MSAlg UA,
(MSAlg UA) Over (MSSign UA)
by MSUHOM_1:20;
MSAlg q9 =
0 .--> q
by A5, MSUHOM_1:def 3
.=
x
by A1, A2, A3, A4
;
then
d is_isomorphism MSAlg UA,
MSAlg UA
by A6, A7, MSUHOM_1:9;
hence
x in MSAAut (MSAlg UA)
by A6, Def7;
verum
end;
let x be set ; TARSKI:def 3 ( not x in MSAAut (MSAlg UA) or x in rng h )
assume A8:
x in MSAAut (MSAlg UA)
; x in rng h
then reconsider f = x as ManySortedFunction of (MSAlg UA),(MSAlg UA) by Def6;
the carrier of (MSSign UA) = {0 }
by MSUALG_1:def 13;
then A9:
f = 0 .--> (f . 0 )
by Th12;
A10:
f is_isomorphism MSAlg UA, MSAlg UA
by A8, Def7;
ex q being set st
( q in dom h & x = h . q )
hence
x in rng h
by FUNCT_1:def 5; verum
reconsider g = (*--> 0 ) * (signature UA) as Function of (dom (signature UA)),({0 } * ) by MSUALG_1:7;