Metamath Proof Explorer


Theorem pco1

Description: The ending point of a path concatenation. (Contributed by Jeff Madsen, 15-Jun-2010)

Ref Expression
Hypotheses pcoval.2 φ F II Cn J
pcoval.3 φ G II Cn J
Assertion pco1 φ F * 𝑝 J G 1 = G 1

Proof

Step Hyp Ref Expression
1 pcoval.2 φ F II Cn J
2 pcoval.3 φ G II Cn J
3 1 2 pcoval φ F * 𝑝 J G = x 0 1 if x 1 2 F 2 x G 2 x 1
4 3 fveq1d φ F * 𝑝 J G 1 = x 0 1 if x 1 2 F 2 x G 2 x 1 1
5 1elunit 1 0 1
6 halflt1 1 2 < 1
7 halfre 1 2
8 1re 1
9 7 8 ltnlei 1 2 < 1 ¬ 1 1 2
10 6 9 mpbi ¬ 1 1 2
11 breq1 x = 1 x 1 2 1 1 2
12 10 11 mtbiri x = 1 ¬ x 1 2
13 12 iffalsed x = 1 if x 1 2 F 2 x G 2 x 1 = G 2 x 1
14 oveq2 x = 1 2 x = 2 1
15 2t1e2 2 1 = 2
16 14 15 eqtrdi x = 1 2 x = 2
17 16 oveq1d x = 1 2 x 1 = 2 1
18 2m1e1 2 1 = 1
19 17 18 eqtrdi x = 1 2 x 1 = 1
20 19 fveq2d x = 1 G 2 x 1 = G 1
21 13 20 eqtrd x = 1 if x 1 2 F 2 x G 2 x 1 = G 1
22 eqid x 0 1 if x 1 2 F 2 x G 2 x 1 = x 0 1 if x 1 2 F 2 x G 2 x 1
23 fvex G 1 V
24 21 22 23 fvmpt 1 0 1 x 0 1 if x 1 2 F 2 x G 2 x 1 1 = G 1
25 5 24 ax-mp x 0 1 if x 1 2 F 2 x G 2 x 1 1 = G 1
26 4 25 eqtrdi φ F * 𝑝 J G 1 = G 1