let C be non empty compact non horizontal non vertical Subset of (TOP-REAL 2); for n being Element of NAT holds L~ (Cage C,n) = (L~ (Upper_Seq C,n)) \/ (L~ (Lower_Seq C,n))
let n be Element of NAT ; L~ (Cage C,n) = (L~ (Upper_Seq C,n)) \/ (L~ (Lower_Seq C,n))
E-max (L~ (Cage C,n)) in rng (Cage C,n)
by SPRECT_2:50;
then
E-max (L~ (Cage C,n)) in rng (Rotate (Cage C,n),(W-min (L~ (Cage C,n))))
by FINSEQ_6:96, SPRECT_2:47;
then
L~ (Rotate (Cage C,n),(W-min (L~ (Cage C,n)))) = (L~ (Upper_Seq C,n)) \/ (L~ (Lower_Seq C,n))
by SPPOL_2:25;
hence
L~ (Cage C,n) = (L~ (Upper_Seq C,n)) \/ (L~ (Lower_Seq C,n))
by REVROT_1:33; verum