Metamath Proof Explorer


Theorem tgbtwnconn2

Description: Another connectivity law for betweenness. Theorem 5.2 of Schwabhauser p. 41. (Contributed by Thierry Arnoux, 17-May-2019)

Ref Expression
Hypotheses tgbtwnconn.p
|- P = ( Base ` G )
tgbtwnconn.i
|- I = ( Itv ` G )
tgbtwnconn.g
|- ( ph -> G e. TarskiG )
tgbtwnconn.a
|- ( ph -> A e. P )
tgbtwnconn.b
|- ( ph -> B e. P )
tgbtwnconn.c
|- ( ph -> C e. P )
tgbtwnconn.d
|- ( ph -> D e. P )
tgbtwnconn2.1
|- ( ph -> A =/= B )
tgbtwnconn2.2
|- ( ph -> B e. ( A I C ) )
tgbtwnconn2.3
|- ( ph -> B e. ( A I D ) )
Assertion tgbtwnconn2
|- ( ph -> ( C e. ( B I D ) \/ D e. ( B I C ) ) )

Proof

Step Hyp Ref Expression
1 tgbtwnconn.p
 |-  P = ( Base ` G )
2 tgbtwnconn.i
 |-  I = ( Itv ` G )
3 tgbtwnconn.g
 |-  ( ph -> G e. TarskiG )
4 tgbtwnconn.a
 |-  ( ph -> A e. P )
5 tgbtwnconn.b
 |-  ( ph -> B e. P )
6 tgbtwnconn.c
 |-  ( ph -> C e. P )
7 tgbtwnconn.d
 |-  ( ph -> D e. P )
8 tgbtwnconn2.1
 |-  ( ph -> A =/= B )
9 tgbtwnconn2.2
 |-  ( ph -> B e. ( A I C ) )
10 tgbtwnconn2.3
 |-  ( ph -> B e. ( A I D ) )
11 eqid
 |-  ( dist ` G ) = ( dist ` G )
12 3 adantr
 |-  ( ( ph /\ C e. ( A I D ) ) -> G e. TarskiG )
13 4 adantr
 |-  ( ( ph /\ C e. ( A I D ) ) -> A e. P )
14 5 adantr
 |-  ( ( ph /\ C e. ( A I D ) ) -> B e. P )
15 6 adantr
 |-  ( ( ph /\ C e. ( A I D ) ) -> C e. P )
16 7 adantr
 |-  ( ( ph /\ C e. ( A I D ) ) -> D e. P )
17 9 adantr
 |-  ( ( ph /\ C e. ( A I D ) ) -> B e. ( A I C ) )
18 simpr
 |-  ( ( ph /\ C e. ( A I D ) ) -> C e. ( A I D ) )
19 1 11 2 12 13 14 15 16 17 18 tgbtwnexch3
 |-  ( ( ph /\ C e. ( A I D ) ) -> C e. ( B I D ) )
20 19 orcd
 |-  ( ( ph /\ C e. ( A I D ) ) -> ( C e. ( B I D ) \/ D e. ( B I C ) ) )
21 3 adantr
 |-  ( ( ph /\ D e. ( A I C ) ) -> G e. TarskiG )
22 4 adantr
 |-  ( ( ph /\ D e. ( A I C ) ) -> A e. P )
23 5 adantr
 |-  ( ( ph /\ D e. ( A I C ) ) -> B e. P )
24 7 adantr
 |-  ( ( ph /\ D e. ( A I C ) ) -> D e. P )
25 6 adantr
 |-  ( ( ph /\ D e. ( A I C ) ) -> C e. P )
26 10 adantr
 |-  ( ( ph /\ D e. ( A I C ) ) -> B e. ( A I D ) )
27 simpr
 |-  ( ( ph /\ D e. ( A I C ) ) -> D e. ( A I C ) )
28 1 11 2 21 22 23 24 25 26 27 tgbtwnexch3
 |-  ( ( ph /\ D e. ( A I C ) ) -> D e. ( B I C ) )
29 28 olcd
 |-  ( ( ph /\ D e. ( A I C ) ) -> ( C e. ( B I D ) \/ D e. ( B I C ) ) )
30 1 2 3 4 5 6 7 8 9 10 tgbtwnconn1
 |-  ( ph -> ( C e. ( A I D ) \/ D e. ( A I C ) ) )
31 20 29 30 mpjaodan
 |-  ( ph -> ( C e. ( B I D ) \/ D e. ( B I C ) ) )