reserve c for Complex;
reserve r for Real;
reserve m,n for Nat;
reserve f for complex-valued Function;
reserve f,g for differentiable Function of REAL,REAL;
reserve L for non empty ZeroStr;
reserve x for Element of L;
reserve p,q for Polynomial of F_Real;

theorem
  Eval(p-q) = Eval(p) - Eval(q)
  proof
    thus Eval(p-q) = Eval(p) + Eval(-q) by Th55
    .= Eval(p) - Eval(q) by Th56;
  end;
