
theorem
  for F being Field holds for a,b being Element of NonZero F holds ovf(F
  ).(a,b) = revf(F).(ovf(F).(b,a))
proof
  let F be Field;
  let a,b be Element of NonZero F;
  ovf(F).(a,b) = omf(F).(a,revf(F).b) by Def2
    .= revf(F).(omf(F).(b,revf(F).a)) by Th2;
  hence thesis by Def2;
end;
