reserve k,j,n for Nat,
  r for Real;
reserve x,x1,x2,y for Element of REAL n;
reserve f for real-valued FinSequence;
reserve p,p1,p2,p3 for Point of TOP-REAL n,
  x,x1,x2,y,y1,y2 for Real;
reserve p,p1,p2 for Point of TOP-REAL 2;

theorem
  abs 1*n = n |-> 1
proof
  thus abs 1*n = abs(n |-> jj)
    .= n |-> absreal.1 by FINSEQOP:16
    .= n |-> |.1.| by Def2
    .= n |-> 1 by ABSVALUE:def 1;
end;
