
theorem Th14:
  for V being RealNormSpace,
      x be Point of V holds
    x .|. 0.(DualSp V) = 0
proof
  let V be RealNormSpace,
      x be Point of V;
  thus x .|. 0.(DualSp V)
  = x .|. ( 0 * ( 0.(DualSp V)))
  .= 0* x .|.0.(DualSp V) by DUALSP01:30
  .= 0;
end;
