theorem Th46:
  f is A-measurable implies max+f is A-measurable
proof
  assume f is A-measurable;
  then R_EAL f is A-measurable;
  then max+(R_EAL f) is A-measurable by MESFUNC2:25;
  then R_EAL(max+f) is A-measurable by Th30;
  hence thesis;
end;
