let f1, f2 be Function of [:[:(free_magma X,n),(free_magma X,m):],{n}:],M; ( ( for x being Element of [:[:(free_magma X,n),(free_magma X,m):],{n}:]
for y being Element of free_magma X,n
for z being Element of free_magma X,m st y = (x `1 ) `1 & z = (x `1 ) `2 holds
f1 . x = (f . y) * (g . z) ) & ( for x being Element of [:[:(free_magma X,n),(free_magma X,m):],{n}:]
for y being Element of free_magma X,n
for z being Element of free_magma X,m st y = (x `1 ) `1 & z = (x `1 ) `2 holds
f2 . x = (f . y) * (g . z) ) implies f1 = f2 )
assume A4:
for x being Element of [:[:(free_magma X,n),(free_magma X,m):],{n}:]
for y being Element of free_magma X,n
for z being Element of free_magma X,m st y = (x `1 ) `1 & z = (x `1 ) `2 holds
f1 . x = (f . y) * (g . z)
; ( ex x being Element of [:[:(free_magma X,n),(free_magma X,m):],{n}:] ex y being Element of free_magma X,n ex z being Element of free_magma X,m st
( y = (x `1 ) `1 & z = (x `1 ) `2 & not f2 . x = (f . y) * (g . z) ) or f1 = f2 )
assume A5:
for x being Element of [:[:(free_magma X,n),(free_magma X,m):],{n}:]
for y being Element of free_magma X,n
for z being Element of free_magma X,m st y = (x `1 ) `1 & z = (x `1 ) `2 holds
f2 . x = (f . y) * (g . z)
; f1 = f2
for x being set st x in [:[:(free_magma X,n),(free_magma X,m):],{n}:] holds
f1 . x = f2 . x
proof
let x be
set ;
( x in [:[:(free_magma X,n),(free_magma X,m):],{n}:] implies f1 . x = f2 . x )
assume
x in [:[:(free_magma X,n),(free_magma X,m):],{n}:]
;
f1 . x = f2 . x
then reconsider x9 =
x as
Element of
[:[:(free_magma X,n),(free_magma X,m):],{n}:] ;
A6:
x9 `1 in [:(free_magma X,n),(free_magma X,m):]
by MCART_1:10;
then reconsider x1 =
(x9 `1 ) `1 as
Element of
free_magma X,
n by MCART_1:10;
reconsider x2 =
(x9 `1 ) `2 as
Element of
free_magma X,
m by A6, MCART_1:10;
thus f1 . x =
(f . x1) * (g . x2)
by A4
.=
f2 . x
by A5
;
verum
end;
hence
f1 = f2
by FUNCT_2:18; verum