
theorem Lm3b:
for n being Nat, m being non zero Nat holds n/m is Nat iff m divides n
proof
let n be Nat, m be non zero Nat;
thus n/m is Nat implies m divides n by WSIERP_1:17;
H: n * 1 = n * (m/m) by XCMPLX_1:60;
  assume m divides n; then
  consider x being Nat such that A1: m * x = n by NAT_D:def 3;
  m * (n/m) = m * x by A1,H;
  hence n/m is Nat by XCMPLX_1:5;
end;
