| Step | Hyp | Ref | Expression | 
						
							| 1 |  | drngi.1 |  | 
						
							| 2 |  | drngi.2 |  | 
						
							| 3 |  | drngi.3 |  | 
						
							| 4 |  | drngi.4 |  | 
						
							| 5 |  | opeq1 |  | 
						
							| 6 | 5 | eleq1d |  | 
						
							| 7 |  | id |  | 
						
							| 8 | 7 1 | eqtr4di |  | 
						
							| 9 | 8 | rneqd |  | 
						
							| 10 | 9 3 | eqtr4di |  | 
						
							| 11 | 8 | fveq2d |  | 
						
							| 12 | 11 4 | eqtr4di |  | 
						
							| 13 | 12 | sneqd |  | 
						
							| 14 | 10 13 | difeq12d |  | 
						
							| 15 | 14 | sqxpeqd |  | 
						
							| 16 | 15 | reseq2d |  | 
						
							| 17 | 16 | eleq1d |  | 
						
							| 18 | 6 17 | anbi12d |  | 
						
							| 19 |  | opeq2 |  | 
						
							| 20 | 19 | eleq1d |  | 
						
							| 21 | 20 | anbi1d |  | 
						
							| 22 |  | id |  | 
						
							| 23 | 2 22 | eqtr4id |  | 
						
							| 24 | 23 | reseq1d |  | 
						
							| 25 | 24 | eleq1d |  | 
						
							| 26 | 25 | anbi2d |  | 
						
							| 27 | 21 26 | bitr4d |  | 
						
							| 28 | 18 27 | elopabi |  | 
						
							| 29 |  | df-drngo |  | 
						
							| 30 | 28 29 | eleq2s |  | 
						
							| 31 | 29 | relopabiv |  | 
						
							| 32 |  | 1st2nd |  | 
						
							| 33 | 31 32 | mpan |  | 
						
							| 34 | 33 | eleq1d |  | 
						
							| 35 | 34 | anbi1d |  | 
						
							| 36 | 30 35 | mpbird |  |