 reserve n for Nat;

theorem
   for R being Ring, S being R-homomorphic Ring
   for h being Homomorphism of R,S
   for p,q being Element of the carrier of Polynom-Ring R
   holds (PolyHom h).(p+q) = (PolyHom h).p + (PolyHom h).q by VECTSP_1:def 20;
