reserve n,n1,n2,m for Nat;
reserve r,g1,g2,g,g9 for Complex;
reserve R,R2 for Real;
reserve s,s9,s1 for Complex_Sequence;

theorem Th18:
  for s,s9 being convergent Complex_Sequence
  holds lim(s - s9)=(lim s)-( lim s9)
proof
  let s,s9 be convergent Complex_Sequence;
  lim(s - s9) = (lim s) + lim(-s9) by Th12
    .= (lim s) + -(lim s9) by Th16;
  hence thesis;
end;
