reserve FT for non empty RelStr;
reserve A for Subset of FT;
reserve T for non empty TopStruct;
reserve FMT for non empty FMT_Space_Str;
reserve x, y for Element of FMT;
reserve A, B, W, V for Subset of FMT;

theorem Th29:
  (A /\ B)^Foi c= ((A^Foi) /\ (B^Foi))
proof
  let x be object;
  assume
A1: x in (A /\ B)^Foi;
  (A /\ B)^Foi c= A^Foi & (B /\ A)^Foi c= B^Foi by Th25,XBOOLE_1:17;
  hence thesis by A1,XBOOLE_0:def 4;
end;
