reserve i,n,m for Nat;

theorem Th1:
for f be set holds
 f is PartFunc of REAL m,REAL n iff f is PartFunc of REAL-NS m,REAL-NS n
proof
   let f be set;
   the carrier of REAL-NS m = REAL m &
   the carrier of REAL-NS n = REAL n by REAL_NS1:def 4;
   hence thesis;
end;
