reserve x,y,X for set,
  i,j,k,m,n for Nat,
  p for FinSequence of X,
  ii for Integer;
reserve G for Graph,
  pe,qe for FinSequence of the carrier' of G,
  p,q for oriented Chain of G,
  W for Function,
  U,V,e,ee for set,
  v1,v2,v3,v4 for Vertex of G;
reserve G for finite Graph,
  P,Q for oriented Chain of G,
  v1,v2,v3 for Vertex of G;
reserve G for finite oriented Graph,
  P,Q for oriented Chain of G,
  W for Function of (the carrier' of G), Real>=0,
  v1,v2,v3,v4 for Vertex of G;
reserve f,g,h for Element of REAL*,
  r for Real;

theorem Th21:
  for F being Element of Funcs(REAL*,REAL*), f being Element of
  REAL*,n,i be Element of NAT holds (repeat F).0 .f = f
proof
  let F be Element of Funcs(REAL*,REAL*), f be Element of REAL*,n,i be Element
  of NAT;
  thus (repeat F).0 .f = (id (REAL*)).f by Def2
    .= f;
end;
