set f = Polynom-Evaluation n,L,x;
for p, q being Element of holds (Polynom-Evaluation n,L,x) . (p * q) = ((Polynom-Evaluation n,L,x) . p) * ((Polynom-Evaluation n,L,x) . q)
proof
let p,
q be
Element of ;
(Polynom-Evaluation n,L,x) . (p * q) = ((Polynom-Evaluation n,L,x) . p) * ((Polynom-Evaluation n,L,x) . q)
reconsider p' =
p,
q' =
q as
Polynomial of
n,
L by POLYNOM1:def 27;
reconsider p =
p,
q =
q as
Element of ;
A1:
(Polynom-Evaluation n,L,x) . p = eval p',
x
by Def5;
(Polynom-Evaluation n,L,x) . (p * q) =
(Polynom-Evaluation n,L,x) . (p' *' q')
by POLYNOM1:def 27
.=
eval (p' *' q'),
x
by Def5
.=
(eval p',x) * (eval q',x)
by Th27
;
hence
(Polynom-Evaluation n,L,x) . (p * q) = ((Polynom-Evaluation n,L,x) . p) * ((Polynom-Evaluation n,L,x) . q)
by A1, Def5;
verum
end;
hence
Polynom-Evaluation n,L,x is multiplicative
by GROUP_6:def 7; verum