let f be non empty one-to-one unfolded s.n.c. FinSequence of (TOP-REAL 2); for g being non trivial one-to-one unfolded s.n.c. FinSequence of (TOP-REAL 2)
for i, j being Nat st j > len f & j + 1 < len (f ^' g) holds
for x being Point of (TOP-REAL 2) st x in (LSeg ((f ^' g),i)) /\ (LSeg ((f ^' g),j)) holds
x <> g /. (len g)
let g be non trivial one-to-one unfolded s.n.c. FinSequence of (TOP-REAL 2); for i, j being Nat st j > len f & j + 1 < len (f ^' g) holds
for x being Point of (TOP-REAL 2) st x in (LSeg ((f ^' g),i)) /\ (LSeg ((f ^' g),j)) holds
x <> g /. (len g)
let i, j be Nat; ( j > len f & j + 1 < len (f ^' g) implies for x being Point of (TOP-REAL 2) st x in (LSeg ((f ^' g),i)) /\ (LSeg ((f ^' g),j)) holds
x <> g /. (len g) )
assume that
A1:
j > len f
and
A2:
j + 1 < len (f ^' g)
; for x being Point of (TOP-REAL 2) st x in (LSeg ((f ^' g),i)) /\ (LSeg ((f ^' g),j)) holds
x <> g /. (len g)
consider k being Nat such that
A3:
j = (len f) + k
by A1, NAT_1:10;
(len (f ^' g)) + 1 = (len f) + (len g)
by FINSEQ_6:139;
then A4:
(j + 1) + 1 < (len f) + (len g)
by A2, XREAL_1:6;
reconsider k = k as Nat ;
(j + 1) + 1 = (len f) + ((k + 1) + 1)
by A3;
then A5:
(k + 1) + 1 < len g
by A4, XREAL_1:6;
1 <= (k + 1) + 1
by NAT_1:11;
then A6:
(k + 1) + 1 in dom g
by A5, FINSEQ_3:25;
let x be Point of (TOP-REAL 2); ( x in (LSeg ((f ^' g),i)) /\ (LSeg ((f ^' g),j)) implies x <> g /. (len g) )
assume A7:
x in (LSeg ((f ^' g),i)) /\ (LSeg ((f ^' g),j))
; x <> g /. (len g)
A8:
len g in dom g
by FINSEQ_5:6;
A9:
k + 1 <= (k + 1) + 1
by NAT_1:11;
then A10:
k + 1 < len g
by A5, XXREAL_0:2;
then A11:
(LSeg (g,(k + 1))) /\ (rng g) = {(g /. (k + 1)),(g /. ((k + 1) + 1))}
by Th32, NAT_1:11;
assume A12:
x = g /. (len g)
; contradiction
x = g . (len g)
by A12, A8, PARTFUN1:def 6;
then A13:
x in rng g
by A8, FUNCT_1:3;
1 <= k + 1
by NAT_1:11;
then A14:
k + 1 in dom g
by A10, FINSEQ_3:25;
(len f) + 0 < (len f) + k
by A1, A3;
then
0 < k
;
then
0 + 1 <= k
by NAT_1:13;
then
LSeg ((f ^' g),j) = LSeg (g,(k + 1))
by A3, A10, Th29;
then
x in LSeg (g,(k + 1))
by A7, XBOOLE_0:def 4;
then
x in (LSeg (g,(k + 1))) /\ (rng g)
by A13, XBOOLE_0:def 4;
then
( x = g /. (k + 1) or x = g /. ((k + 1) + 1) )
by A11, TARSKI:def 2;
hence
contradiction
by A12, A5, A9, A8, A14, A6, PARTFUN2:10; verum