| Step | Hyp | Ref | Expression | 
						
							| 1 |  | isvclem.1 |  | 
						
							| 2 |  | df-vc |  | 
						
							| 3 | 2 | eleq2i |  | 
						
							| 4 |  | eleq1 |  | 
						
							| 5 |  | rneq |  | 
						
							| 6 | 5 1 | eqtr4di |  | 
						
							| 7 |  | xpeq2 |  | 
						
							| 8 | 7 | feq2d |  | 
						
							| 9 |  | feq3 |  | 
						
							| 10 | 8 9 | bitrd |  | 
						
							| 11 | 6 10 | syl |  | 
						
							| 12 |  | oveq |  | 
						
							| 13 | 12 | oveq2d |  | 
						
							| 14 |  | oveq |  | 
						
							| 15 | 13 14 | eqeq12d |  | 
						
							| 16 | 6 15 | raleqbidv |  | 
						
							| 17 |  | oveq |  | 
						
							| 18 | 17 | eqeq2d |  | 
						
							| 19 | 18 | anbi1d |  | 
						
							| 20 | 19 | ralbidv |  | 
						
							| 21 | 16 20 | anbi12d |  | 
						
							| 22 | 21 | ralbidv |  | 
						
							| 23 | 22 | anbi2d |  | 
						
							| 24 | 6 23 | raleqbidv |  | 
						
							| 25 | 4 11 24 | 3anbi123d |  | 
						
							| 26 |  | feq1 |  | 
						
							| 27 |  | oveq |  | 
						
							| 28 | 27 | eqeq1d |  | 
						
							| 29 |  | oveq |  | 
						
							| 30 |  | oveq |  | 
						
							| 31 |  | oveq |  | 
						
							| 32 | 30 31 | oveq12d |  | 
						
							| 33 | 29 32 | eqeq12d |  | 
						
							| 34 | 33 | ralbidv |  | 
						
							| 35 |  | oveq |  | 
						
							| 36 |  | oveq |  | 
						
							| 37 | 30 36 | oveq12d |  | 
						
							| 38 | 35 37 | eqeq12d |  | 
						
							| 39 |  | oveq |  | 
						
							| 40 |  | oveq |  | 
						
							| 41 | 36 | oveq2d |  | 
						
							| 42 | 40 41 | eqtrd |  | 
						
							| 43 | 39 42 | eqeq12d |  | 
						
							| 44 | 38 43 | anbi12d |  | 
						
							| 45 | 44 | ralbidv |  | 
						
							| 46 | 34 45 | anbi12d |  | 
						
							| 47 | 46 | ralbidv |  | 
						
							| 48 | 28 47 | anbi12d |  | 
						
							| 49 | 48 | ralbidv |  | 
						
							| 50 | 26 49 | 3anbi23d |  | 
						
							| 51 | 25 50 | opelopabg |  | 
						
							| 52 | 3 51 | bitrid |  |