| Step | Hyp | Ref | Expression | 
						
							| 1 |  | oppcbas.1 |  | 
						
							| 2 |  | eqid |  | 
						
							| 3 | 1 2 | oppcbas |  | 
						
							| 4 | 3 | a1i |  | 
						
							| 5 |  | eqidd |  | 
						
							| 6 |  | eqidd |  | 
						
							| 7 | 1 | fvexi |  | 
						
							| 8 | 7 | a1i |  | 
						
							| 9 |  | biid |  | 
						
							| 10 |  | eqid |  | 
						
							| 11 |  | eqid |  | 
						
							| 12 |  | simpl |  | 
						
							| 13 |  | simpr |  | 
						
							| 14 | 2 10 11 12 13 | catidcl |  | 
						
							| 15 | 10 1 | oppchom |  | 
						
							| 16 | 14 15 | eleqtrrdi |  | 
						
							| 17 |  | eqid |  | 
						
							| 18 |  | simpr1l |  | 
						
							| 19 |  | simpr1r |  | 
						
							| 20 | 2 17 1 18 19 19 | oppcco |  | 
						
							| 21 |  | simpl |  | 
						
							| 22 |  | simpr31 |  | 
						
							| 23 | 10 1 | oppchom |  | 
						
							| 24 | 22 23 | eleqtrdi |  | 
						
							| 25 | 2 10 11 21 19 17 18 24 | catrid |  | 
						
							| 26 | 20 25 | eqtrd |  | 
						
							| 27 |  | simpr2l |  | 
						
							| 28 | 2 17 1 19 19 27 | oppcco |  | 
						
							| 29 |  | simpr32 |  | 
						
							| 30 | 10 1 | oppchom |  | 
						
							| 31 | 29 30 | eleqtrdi |  | 
						
							| 32 | 2 10 11 21 27 17 19 31 | catlid |  | 
						
							| 33 | 28 32 | eqtrd |  | 
						
							| 34 | 2 17 1 18 19 27 | oppcco |  | 
						
							| 35 | 2 10 17 21 27 19 18 31 24 | catcocl |  | 
						
							| 36 | 34 35 | eqeltrd |  | 
						
							| 37 | 10 1 | oppchom |  | 
						
							| 38 | 36 37 | eleqtrrdi |  | 
						
							| 39 |  | simpr2r |  | 
						
							| 40 |  | simpr33 |  | 
						
							| 41 | 10 1 | oppchom |  | 
						
							| 42 | 40 41 | eleqtrdi |  | 
						
							| 43 | 2 10 17 21 39 27 19 42 31 18 24 | catass |  | 
						
							| 44 | 2 17 1 18 27 39 | oppcco |  | 
						
							| 45 | 2 17 1 18 19 39 | oppcco |  | 
						
							| 46 | 43 44 45 | 3eqtr4rd |  | 
						
							| 47 | 2 17 1 19 27 39 | oppcco |  | 
						
							| 48 | 47 | oveq1d |  | 
						
							| 49 | 34 | oveq2d |  | 
						
							| 50 | 46 48 49 | 3eqtr4d |  | 
						
							| 51 | 4 5 6 8 9 16 26 33 38 50 | iscatd2 |  | 
						
							| 52 | 2 11 | cidfn |  | 
						
							| 53 |  | dffn5 |  | 
						
							| 54 | 52 53 | sylib |  | 
						
							| 55 | 54 | eqeq2d |  | 
						
							| 56 | 55 | anbi2d |  | 
						
							| 57 | 51 56 | mpbird |  |