reserve X for non empty UNITSTR;
reserve a, b for Real;
reserve x, y for Point of X;
reserve X for RealUnitarySpace;
reserve x, y, z, u, v for Point of X;

theorem Th34:
  dist(x,x) = 0
proof
  thus dist(x,x) = ||.09(X).|| by RLVECT_1:15
    .= 0 by Th26;
end;
