Description: Outer transitivity law for betweenness. Left-hand side of Theorem 3.1 of Schwabhauser p. 30. (Contributed by Scott Fenton, 12-Jun-2013)
Ref | Expression | ||
---|---|---|---|
Assertion | btwnouttr2 | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | simp1 | |
|
2 | simp2l | |
|
3 | simp3l | |
|
4 | simp3r | |
|
5 | axsegcon | |
|
6 | 1 2 3 3 4 5 | syl122anc | |
7 | 6 | adantr | |
8 | simprrl | |
|
9 | simprl1 | |
|
10 | simpl2 | |
|
11 | simprl | |
|
12 | 10 11 | jca | |
13 | 12 | adantl | |
14 | simpl1 | |
|
15 | simpl2l | |
|
16 | simpl2r | |
|
17 | simpl3l | |
|
18 | simpr | |
|
19 | btwnexch3 | |
|
20 | 14 15 16 17 18 19 | syl122anc | |
21 | 20 | adantr | |
22 | 13 21 | mpd | |
23 | simprrr | |
|
24 | 22 23 | jca | |
25 | simprl3 | |
|
26 | simpl3r | |
|
27 | 14 17 26 | cgrrflxd | |
28 | 27 | adantr | |
29 | 25 28 | jca | |
30 | segconeq | |
|
31 | 14 17 17 26 16 18 26 30 | syl133anc | |
32 | 31 | adantr | |
33 | 9 24 29 32 | mp3and | |
34 | 33 | opeq2d | |
35 | 8 34 | breqtrd | |
36 | 35 | expr | |
37 | 36 | an32s | |
38 | 37 | rexlimdva | |
39 | 7 38 | mpd | |
40 | 39 | ex | |