| Step | Hyp | Ref | Expression | 
						
							| 1 |  | df-mpo |  | 
						
							| 2 |  | df-mpo |  | 
						
							| 3 | 1 2 | eqeq12i |  | 
						
							| 4 |  | eqoprab2bw |  | 
						
							| 5 |  | pm5.32 |  | 
						
							| 6 | 5 | albii |  | 
						
							| 7 |  | 19.21v |  | 
						
							| 8 | 6 7 | bitr3i |  | 
						
							| 9 | 8 | 2albii |  | 
						
							| 10 |  | r2al |  | 
						
							| 11 | 9 10 | bitr4i |  | 
						
							| 12 | 3 4 11 | 3bitri |  | 
						
							| 13 |  | pm13.183 |  | 
						
							| 14 | 13 | ralimi |  | 
						
							| 15 |  | ralbi |  | 
						
							| 16 | 14 15 | syl |  | 
						
							| 17 | 16 | ralimi |  | 
						
							| 18 |  | ralbi |  | 
						
							| 19 | 17 18 | syl |  | 
						
							| 20 | 12 19 | bitr4id |  |