let f be FinSequence of (TOP-REAL 2); :: thesis: for Q being Subset of (TOP-REAL 2)
for q being Point of (TOP-REAL 2)
for i being Element of NAT st L~ f meets Q & f is being_S-Seq & Q is closed & Last_Point (L~ f),(f /. 1),(f /. (len f)),Q in LSeg f,i & 1 <= i & i + 1 <= len f & q in LSeg f,i & q in Q holds
LE q, Last_Point (L~ f),(f /. 1),(f /. (len f)),Q,f /. i,f /. (i + 1)
let Q be Subset of (TOP-REAL 2); :: thesis: for q being Point of (TOP-REAL 2)
for i being Element of NAT st L~ f meets Q & f is being_S-Seq & Q is closed & Last_Point (L~ f),(f /. 1),(f /. (len f)),Q in LSeg f,i & 1 <= i & i + 1 <= len f & q in LSeg f,i & q in Q holds
LE q, Last_Point (L~ f),(f /. 1),(f /. (len f)),Q,f /. i,f /. (i + 1)
let q be Point of (TOP-REAL 2); :: thesis: for i being Element of NAT st L~ f meets Q & f is being_S-Seq & Q is closed & Last_Point (L~ f),(f /. 1),(f /. (len f)),Q in LSeg f,i & 1 <= i & i + 1 <= len f & q in LSeg f,i & q in Q holds
LE q, Last_Point (L~ f),(f /. 1),(f /. (len f)),Q,f /. i,f /. (i + 1)
let i be Element of NAT ; :: thesis: ( L~ f meets Q & f is being_S-Seq & Q is closed & Last_Point (L~ f),(f /. 1),(f /. (len f)),Q in LSeg f,i & 1 <= i & i + 1 <= len f & q in LSeg f,i & q in Q implies LE q, Last_Point (L~ f),(f /. 1),(f /. (len f)),Q,f /. i,f /. (i + 1) )
assume A1:
( L~ f meets Q & f is being_S-Seq & Q is closed & Last_Point (L~ f),(f /. 1),(f /. (len f)),Q in LSeg f,i & 1 <= i & i + 1 <= len f & q in LSeg f,i & q in Q )
; :: thesis: LE q, Last_Point (L~ f),(f /. 1),(f /. (len f)),Q,f /. i,f /. (i + 1)
then
(LSeg f,i) /\ Q <> {}
by XBOOLE_0:def 4;
then A2:
LSeg f,i meets Q
by XBOOLE_0:def 7;
len f >= 2
by A1, TOPREAL1:def 10;
then reconsider P = L~ f, R = LSeg f,i as non empty Subset of (TOP-REAL 2) by A1, TOPREAL1:29;
Last_Point P,(f /. 1),(f /. (len f)),Q = Last_Point R,(f /. i),(f /. (i + 1)),Q
by A1, Th20;
hence
LE q, Last_Point (L~ f),(f /. 1),(f /. (len f)),Q,f /. i,f /. (i + 1)
by A1, A2, Lm4; :: thesis: verum