| Step | Hyp | Ref | Expression | 
						
							| 1 |  | sseq2 |  | 
						
							| 2 | 1 | 3ad2ant2 |  | 
						
							| 3 |  | predeq1 |  | 
						
							| 4 |  | predeq2 |  | 
						
							| 5 | 3 4 | sylan9eq |  | 
						
							| 6 | 5 | 3adant3 |  | 
						
							| 7 | 6 | sseq1d |  | 
						
							| 8 | 7 | ralbidv |  | 
						
							| 9 | 2 8 | anbi12d |  | 
						
							| 10 |  | simp3 |  | 
						
							| 11 | 5 | reseq2d |  | 
						
							| 12 | 11 | 3adant3 |  | 
						
							| 13 | 10 12 | fveq12d |  | 
						
							| 14 | 13 | eqeq2d |  | 
						
							| 15 | 14 | ralbidv |  | 
						
							| 16 | 9 15 | 3anbi23d |  | 
						
							| 17 | 16 | exbidv |  | 
						
							| 18 | 17 | abbidv |  | 
						
							| 19 | 18 | unieqd |  | 
						
							| 20 |  | dfwrecsOLD |  | 
						
							| 21 |  | dfwrecsOLD |  | 
						
							| 22 | 19 20 21 | 3eqtr4g |  |