| Step | Hyp | Ref | Expression | 
						
							| 1 |  | brcolinear2 |  |-  ( ( B e. ( EE ` N ) /\ C e. ( EE ` N ) ) -> ( A Colinear <. B , C >. <-> E. n e. NN ( ( A e. ( EE ` n ) /\ B e. ( EE ` n ) /\ C e. ( EE ` n ) ) /\ ( A Btwn <. B , C >. \/ B Btwn <. C , A >. \/ C Btwn <. A , B >. ) ) ) ) | 
						
							| 2 | 1 | 3adant1 |  |-  ( ( A e. ( EE ` N ) /\ B e. ( EE ` N ) /\ C e. ( EE ` N ) ) -> ( A Colinear <. B , C >. <-> E. n e. NN ( ( A e. ( EE ` n ) /\ B e. ( EE ` n ) /\ C e. ( EE ` n ) ) /\ ( A Btwn <. B , C >. \/ B Btwn <. C , A >. \/ C Btwn <. A , B >. ) ) ) ) | 
						
							| 3 | 2 | adantl |  |-  ( ( N e. NN /\ ( A e. ( EE ` N ) /\ B e. ( EE ` N ) /\ C e. ( EE ` N ) ) ) -> ( A Colinear <. B , C >. <-> E. n e. NN ( ( A e. ( EE ` n ) /\ B e. ( EE ` n ) /\ C e. ( EE ` n ) ) /\ ( A Btwn <. B , C >. \/ B Btwn <. C , A >. \/ C Btwn <. A , B >. ) ) ) ) | 
						
							| 4 |  | simpr |  |-  ( ( ( A e. ( EE ` n ) /\ B e. ( EE ` n ) /\ C e. ( EE ` n ) ) /\ ( A Btwn <. B , C >. \/ B Btwn <. C , A >. \/ C Btwn <. A , B >. ) ) -> ( A Btwn <. B , C >. \/ B Btwn <. C , A >. \/ C Btwn <. A , B >. ) ) | 
						
							| 5 | 4 | rexlimivw |  |-  ( E. n e. NN ( ( A e. ( EE ` n ) /\ B e. ( EE ` n ) /\ C e. ( EE ` n ) ) /\ ( A Btwn <. B , C >. \/ B Btwn <. C , A >. \/ C Btwn <. A , B >. ) ) -> ( A Btwn <. B , C >. \/ B Btwn <. C , A >. \/ C Btwn <. A , B >. ) ) | 
						
							| 6 |  | fveq2 |  |-  ( n = N -> ( EE ` n ) = ( EE ` N ) ) | 
						
							| 7 | 6 | eleq2d |  |-  ( n = N -> ( A e. ( EE ` n ) <-> A e. ( EE ` N ) ) ) | 
						
							| 8 | 6 | eleq2d |  |-  ( n = N -> ( B e. ( EE ` n ) <-> B e. ( EE ` N ) ) ) | 
						
							| 9 | 6 | eleq2d |  |-  ( n = N -> ( C e. ( EE ` n ) <-> C e. ( EE ` N ) ) ) | 
						
							| 10 | 7 8 9 | 3anbi123d |  |-  ( n = N -> ( ( A e. ( EE ` n ) /\ B e. ( EE ` n ) /\ C e. ( EE ` n ) ) <-> ( A e. ( EE ` N ) /\ B e. ( EE ` N ) /\ C e. ( EE ` N ) ) ) ) | 
						
							| 11 | 10 | anbi1d |  |-  ( n = N -> ( ( ( A e. ( EE ` n ) /\ B e. ( EE ` n ) /\ C e. ( EE ` n ) ) /\ ( A Btwn <. B , C >. \/ B Btwn <. C , A >. \/ C Btwn <. A , B >. ) ) <-> ( ( A e. ( EE ` N ) /\ B e. ( EE ` N ) /\ C e. ( EE ` N ) ) /\ ( A Btwn <. B , C >. \/ B Btwn <. C , A >. \/ C Btwn <. A , B >. ) ) ) ) | 
						
							| 12 | 11 | rspcev |  |-  ( ( N e. NN /\ ( ( A e. ( EE ` N ) /\ B e. ( EE ` N ) /\ C e. ( EE ` N ) ) /\ ( A Btwn <. B , C >. \/ B Btwn <. C , A >. \/ C Btwn <. A , B >. ) ) ) -> E. n e. NN ( ( A e. ( EE ` n ) /\ B e. ( EE ` n ) /\ C e. ( EE ` n ) ) /\ ( A Btwn <. B , C >. \/ B Btwn <. C , A >. \/ C Btwn <. A , B >. ) ) ) | 
						
							| 13 | 12 | expr |  |-  ( ( N e. NN /\ ( A e. ( EE ` N ) /\ B e. ( EE ` N ) /\ C e. ( EE ` N ) ) ) -> ( ( A Btwn <. B , C >. \/ B Btwn <. C , A >. \/ C Btwn <. A , B >. ) -> E. n e. NN ( ( A e. ( EE ` n ) /\ B e. ( EE ` n ) /\ C e. ( EE ` n ) ) /\ ( A Btwn <. B , C >. \/ B Btwn <. C , A >. \/ C Btwn <. A , B >. ) ) ) ) | 
						
							| 14 | 5 13 | impbid2 |  |-  ( ( N e. NN /\ ( A e. ( EE ` N ) /\ B e. ( EE ` N ) /\ C e. ( EE ` N ) ) ) -> ( E. n e. NN ( ( A e. ( EE ` n ) /\ B e. ( EE ` n ) /\ C e. ( EE ` n ) ) /\ ( A Btwn <. B , C >. \/ B Btwn <. C , A >. \/ C Btwn <. A , B >. ) ) <-> ( A Btwn <. B , C >. \/ B Btwn <. C , A >. \/ C Btwn <. A , B >. ) ) ) | 
						
							| 15 | 3 14 | bitrd |  |-  ( ( N e. NN /\ ( A e. ( EE ` N ) /\ B e. ( EE ` N ) /\ C e. ( EE ` N ) ) ) -> ( A Colinear <. B , C >. <-> ( A Btwn <. B , C >. \/ B Btwn <. C , A >. \/ C Btwn <. A , B >. ) ) ) |