let i be Nat; for p being Point of (TOP-REAL 2)
for G being Go-board st 1 <= i & i + 1 <= len G holds
LSeg ((((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1)))) - |[0,1]|),p) meets Int (cell (G,i,0))
let p be Point of (TOP-REAL 2); for G being Go-board st 1 <= i & i + 1 <= len G holds
LSeg ((((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1)))) - |[0,1]|),p) meets Int (cell (G,i,0))
let G be Go-board; ( 1 <= i & i + 1 <= len G implies LSeg ((((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1)))) - |[0,1]|),p) meets Int (cell (G,i,0)) )
assume A1:
( 1 <= i & i + 1 <= len G )
; LSeg ((((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1)))) - |[0,1]|),p) meets Int (cell (G,i,0))
now ex a being Element of the carrier of (TOP-REAL 2) st
( a in LSeg ((((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1)))) - |[0,1]|),p) & a in Int (cell (G,i,0)) )take a =
((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1)))) - |[0,1]|;
( a in LSeg ((((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1)))) - |[0,1]|),p) & a in Int (cell (G,i,0)) )thus
a in LSeg (
(((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1)))) - |[0,1]|),
p)
by RLTOPSP1:68;
a in Int (cell (G,i,0))thus
a in Int (cell (G,i,0))
by A1, Th33;
verum end;
hence
LSeg ((((1 / 2) * ((G * (i,1)) + (G * ((i + 1),1)))) - |[0,1]|),p) meets Int (cell (G,i,0))
by XBOOLE_0:3; verum