let p be Point of (TOP-REAL 2); :: thesis: for G being Go-board holds LSeg p,((G * 1,1) - |[1,1]|) meets Int (cell G,0 ,0 )
let G be Go-board; :: thesis: LSeg p,((G * 1,1) - |[1,1]|) meets Int (cell G,0 ,0 )
now take a =
(G * 1,1) - |[1,1]|;
:: thesis: ( a in LSeg p,((G * 1,1) - |[1,1]|) & a in Int (cell G,0 ,0 ) )thus
a in LSeg p,
((G * 1,1) - |[1,1]|)
by RLTOPSP1:69;
:: thesis: a in Int (cell G,0 ,0 )thus
a in Int (cell G,0 ,0 )
by Th39;
:: thesis: verum end;
hence
LSeg p,((G * 1,1) - |[1,1]|) meets Int (cell G,0 ,0 )
by XBOOLE_0:3; :: thesis: verum