reserve X for set;
reserve k,m,n for Nat;
reserve i for Integer;
reserve a,b,c,d,e,g,p,r,x,y for Real;
reserve z for Complex;

theorem Th12:
  for a being non zero Real holds lim(rseq(a,b,a,d)) = 1
  proof
    let a be non zero Real;
    thus lim(rseq(a,b,a,d)) = a/a by Th11
    .= 1 by XCMPLX_1:60;
  end;
