| Step | Hyp | Ref | Expression | 
						
							| 1 |  | doch1.h |  | 
						
							| 2 |  | doch1.u |  | 
						
							| 3 |  | doch1.o |  | 
						
							| 4 |  | doch1.v |  | 
						
							| 5 |  | doch1.z |  | 
						
							| 6 |  | eqid |  | 
						
							| 7 | 1 6 2 4 | dih1rn |  | 
						
							| 8 |  | eqid |  | 
						
							| 9 | 8 1 6 3 | dochvalr |  | 
						
							| 10 | 7 9 | mpdan |  | 
						
							| 11 |  | eqid |  | 
						
							| 12 | 1 11 6 2 4 | dih1cnv |  | 
						
							| 13 | 12 | fveq2d |  | 
						
							| 14 |  | hlop |  | 
						
							| 15 | 14 | adantr |  | 
						
							| 16 |  | eqid |  | 
						
							| 17 | 16 11 8 | opoc1 |  | 
						
							| 18 | 15 17 | syl |  | 
						
							| 19 | 13 18 | eqtrd |  | 
						
							| 20 | 19 | fveq2d |  | 
						
							| 21 | 16 1 6 2 5 | dih0 |  | 
						
							| 22 | 10 20 21 | 3eqtrd |  |