let C be non empty set ; for f, g, h being Membership_Func of C holds f * (max g,h) = max (f * g),(f * h)
let f, g, h be Membership_Func of C; f * (max g,h) = max (f * g),(f * h)
A1:
C = dom (max (f * g),(f * h))
by FUNCT_2:def 1;
A2:
for c being Element of C st c in C holds
(f * (max g,h)) . c = (max (f * g),(f * h)) . c
proof
let c be
Element of
C;
( c in C implies (f * (max g,h)) . c = (max (f * g),(f * h)) . c )
(f * (max g,h)) . c =
(f . c) * ((max g,h) . c)
by Def2
.=
(f . c) * (max (g . c),(h . c))
by FUZZY_1:6
.=
max ((f . c) * (g . c)),
((f . c) * (h . c))
by Lm2, Th1
.=
max ((f * g) . c),
((f . c) * (h . c))
by Def2
.=
max ((f * g) . c),
((f * h) . c)
by Def2
;
hence
(
c in C implies
(f * (max g,h)) . c = (max (f * g),(f * h)) . c )
by FUZZY_1:6;
verum
end;
C = dom (f * (max g,h))
by FUNCT_2:def 1;
hence
f * (max g,h) = max (f * g),(f * h)
by A1, A2, PARTFUN1:34; verum