
theorem Th60: :: Completetr
  for G being _Graph st G is _trivial holds G is complete
proof
  let G be _Graph;
  assume G is _trivial;
  then consider x being Vertex of G such that
A1: the_Vertices_of G = {x} by GLIB_000:22;
  let u,v being Vertex of G such that
A2: u <> v and
  not u,v are_adjacent;
  u = x by A1,TARSKI:def 1;
  hence contradiction by A1,A2,TARSKI:def 1;
end;
