| Step | Hyp | Ref | Expression | 
						
							| 1 |  | isassa.v |  | 
						
							| 2 |  | isassa.f |  | 
						
							| 3 |  | isassa.b |  | 
						
							| 4 |  | isassa.s |  | 
						
							| 5 |  | isassa.t |  | 
						
							| 6 |  | fvexd |  | 
						
							| 7 |  | fveq2 |  | 
						
							| 8 | 7 2 | eqtr4di |  | 
						
							| 9 |  | fveq2 |  | 
						
							| 10 | 9 3 | eqtr4di |  | 
						
							| 11 | 10 | adantl |  | 
						
							| 12 |  | fveq2 |  | 
						
							| 13 | 12 1 | eqtr4di |  | 
						
							| 14 |  | simpr |  | 
						
							| 15 |  | simpl |  | 
						
							| 16 | 15 | oveqd |  | 
						
							| 17 |  | eqidd |  | 
						
							| 18 | 14 16 17 | oveq123d |  | 
						
							| 19 |  | eqidd |  | 
						
							| 20 | 14 | oveqd |  | 
						
							| 21 | 15 19 20 | oveq123d |  | 
						
							| 22 | 18 21 | eqeq12d |  | 
						
							| 23 |  | eqidd |  | 
						
							| 24 | 15 | oveqd |  | 
						
							| 25 | 14 23 24 | oveq123d |  | 
						
							| 26 | 25 21 | eqeq12d |  | 
						
							| 27 | 22 26 | anbi12d |  | 
						
							| 28 | 4 5 27 | sbcie2s |  | 
						
							| 29 | 13 28 | raleqbidv |  | 
						
							| 30 | 13 29 | raleqbidv |  | 
						
							| 31 | 30 | adantr |  | 
						
							| 32 | 11 31 | raleqbidv |  | 
						
							| 33 | 6 8 32 | sbcied2 |  | 
						
							| 34 |  | df-assa |  | 
						
							| 35 | 33 34 | elrab2 |  | 
						
							| 36 |  | elin |  | 
						
							| 37 | 36 | anbi1i |  | 
						
							| 38 | 35 37 | bitri |  |