| Step | Hyp | Ref | Expression | 
						
							| 1 |  | ismntoplly |  | 
						
							| 2 |  | haustop |  | 
						
							| 3 | 2 | adantl |  | 
						
							| 4 | 3 | biantrurd |  | 
						
							| 5 |  | hmpher |  | 
						
							| 6 |  | errel |  | 
						
							| 7 |  | relelec |  | 
						
							| 8 | 5 6 7 | mp2b |  | 
						
							| 9 |  | hmphsymb |  | 
						
							| 10 | 8 9 | bitr2i |  | 
						
							| 11 | 10 | a1i |  | 
						
							| 12 | 11 | anbi2d |  | 
						
							| 13 | 12 | rexbidv |  | 
						
							| 14 | 13 | 2ralbidv |  | 
						
							| 15 |  | islly |  | 
						
							| 16 | 15 | a1i |  | 
						
							| 17 | 4 14 16 | 3bitr4rd |  | 
						
							| 18 | 17 | pm5.32da |  | 
						
							| 19 | 18 | anbi2d |  | 
						
							| 20 |  | 3anass |  | 
						
							| 21 |  | 3anass |  | 
						
							| 22 | 19 20 21 | 3bitr4g |  | 
						
							| 23 | 22 | adantr |  | 
						
							| 24 | 1 23 | bitrd |  |