| Step | Hyp | Ref | Expression | 
						
							| 1 |  | posrasymb.b |  | 
						
							| 2 |  | posrasymb.l |  | 
						
							| 3 | 2 | breqi |  | 
						
							| 4 |  | simp2 |  | 
						
							| 5 |  | simp3 |  | 
						
							| 6 |  | brxp |  | 
						
							| 7 | 4 5 6 | sylanbrc |  | 
						
							| 8 |  | brin |  | 
						
							| 9 | 8 | rbaib |  | 
						
							| 10 | 7 9 | syl |  | 
						
							| 11 | 3 10 | bitrid |  | 
						
							| 12 | 2 | breqi |  | 
						
							| 13 |  | brxp |  | 
						
							| 14 | 5 4 13 | sylanbrc |  | 
						
							| 15 |  | brin |  | 
						
							| 16 | 15 | rbaib |  | 
						
							| 17 | 14 16 | syl |  | 
						
							| 18 | 12 17 | bitrid |  | 
						
							| 19 | 11 18 | anbi12d |  | 
						
							| 20 |  | eqid |  | 
						
							| 21 | 1 20 | posasymb |  | 
						
							| 22 | 19 21 | bitrd |  |