reserve z,z1,z2 for Complex;
reserve r,x1,x2 for Real;
reserve p0,p,p1,p2,p3,q for Point of TOP-REAL 2;

theorem
  for f being FinSequence of REAL, p being Point of TOP-REAL 2 st len f
  = 2 & p = f holds |.p.|=|.f.|;
