let n, m be Nat; :: thesis: for f being set holds
( f is PartFunc of (REAL m),(REAL n) iff f is PartFunc of (REAL-NS m),(REAL-NS n) )

let f be set ; :: thesis: ( f is PartFunc of (REAL m),(REAL n) iff f is PartFunc of (REAL-NS m),(REAL-NS n) )
( the carrier of (REAL-NS m) = REAL m & the carrier of (REAL-NS n) = REAL n ) by REAL_NS1:def 4;
hence ( f is PartFunc of (REAL m),(REAL n) iff f is PartFunc of (REAL-NS m),(REAL-NS n) ) ; :: thesis: verum