reserve n for Nat,
  k for Integer;
reserve p for polyhedron,
  k for Integer,
  n for Nat;

theorem Th35:
  for c,d being Element of k-chain-space(p), x being Element of k
  -polytopes(p) holds (c+d)@x = (c@x) + (d@x)
proof
  let c,d be Element of k-chain-space(p), x be Element of k-polytopes(p);
  c+d = c \+\ d by BSPACE:def 5;
  hence thesis by BSPACE:15;
end;
