| Step | Hyp | Ref | Expression | 
						
							| 1 |  | ovg.1 |  | 
						
							| 2 |  | ovg.2 |  | 
						
							| 3 |  | ovg.3 |  | 
						
							| 4 |  | ovg.4 |  | 
						
							| 5 |  | ovg.5 |  | 
						
							| 6 |  | df-ov |  | 
						
							| 7 | 5 | fveq1i |  | 
						
							| 8 | 6 7 | eqtri |  | 
						
							| 9 | 8 | eqeq1i |  | 
						
							| 10 |  | eqeq2 |  | 
						
							| 11 |  | opeq2 |  | 
						
							| 12 | 11 | eleq1d |  | 
						
							| 13 | 10 12 | bibi12d |  | 
						
							| 14 | 13 | imbi2d |  | 
						
							| 15 | 4 | ex |  | 
						
							| 16 | 15 | alrimivv |  | 
						
							| 17 |  | fnoprabg |  | 
						
							| 18 | 16 17 | syl |  | 
						
							| 19 |  | eleq1 |  | 
						
							| 20 | 19 | anbi1d |  | 
						
							| 21 |  | eleq1 |  | 
						
							| 22 | 21 | anbi2d |  | 
						
							| 23 | 20 22 | opelopabg |  | 
						
							| 24 | 23 | ibir |  | 
						
							| 25 |  | fnopfvb |  | 
						
							| 26 | 18 24 25 | syl2an |  | 
						
							| 27 | 14 26 | vtoclg |  | 
						
							| 28 | 27 | com12 |  | 
						
							| 29 | 28 | exp32 |  | 
						
							| 30 | 29 | 3imp2 |  | 
						
							| 31 | 20 1 | anbi12d |  | 
						
							| 32 | 22 2 | anbi12d |  | 
						
							| 33 | 3 | anbi2d |  | 
						
							| 34 | 31 32 33 | eloprabg |  | 
						
							| 35 | 34 | adantl |  | 
						
							| 36 | 30 35 | bitrd |  | 
						
							| 37 | 9 36 | bitrid |  | 
						
							| 38 |  | biidd |  | 
						
							| 39 | 38 | bianabs |  | 
						
							| 40 | 39 | 3adant3 |  | 
						
							| 41 | 40 | adantl |  | 
						
							| 42 | 37 41 | bitrd |  |