| Step | Hyp | Ref | Expression | 
						
							| 1 |  | oppcyon.o |  | 
						
							| 2 |  | oppcyon.y |  | 
						
							| 3 |  | oppcyon.m |  | 
						
							| 4 |  | oppcyon.c |  | 
						
							| 5 | 1 | 2oppchomf |  | 
						
							| 6 | 5 | a1i |  | 
						
							| 7 | 1 | 2oppccomf |  | 
						
							| 8 | 7 | a1i |  | 
						
							| 9 | 1 | oppccat |  | 
						
							| 10 | 4 9 | syl |  | 
						
							| 11 |  | eqid |  | 
						
							| 12 | 11 | oppccat |  | 
						
							| 13 | 10 12 | syl |  | 
						
							| 14 | 6 8 4 13 | hofpropd |  | 
						
							| 15 | 3 14 | eqtrid |  | 
						
							| 16 | 15 | oveq2d |  | 
						
							| 17 |  | eqidd |  | 
						
							| 18 |  | eqidd |  | 
						
							| 19 |  | eqid |  | 
						
							| 20 |  | fvex |  | 
						
							| 21 | 20 | rnex |  | 
						
							| 22 | 21 | a1i |  | 
						
							| 23 |  | ssidd |  | 
						
							| 24 | 3 1 19 4 22 23 | hofcl |  | 
						
							| 25 | 17 18 6 8 10 10 4 13 24 | curfpropd |  | 
						
							| 26 |  | eqid |  | 
						
							| 27 | 2 10 11 26 | yonval |  | 
						
							| 28 | 16 25 27 | 3eqtr4rd |  |