reserve X for non empty set,
  Y for set,
  S for SigmaField of X,
  F for sequence of S,
  f,g for PartFunc of X,REAL,
  A,B for Element of S,
  r,s for Real,
  a for Real,
  n for Nat;
reserve X for non empty set,
  S for SigmaField of X,
  f,g for PartFunc of X,REAL,
  A for Element of S,
  r for Real,
  p for Rational;

theorem
  f is A-measurable & g is A-measurable implies ex F being
Function of RAT,S st for p being Rational holds F.p = (A /\ less_dom(f,p)) /\ (
  A /\ less_dom(g,r-p))
by MESFUNC2:6;
