| Step | Hyp | Ref | Expression | 
						
							| 1 |  | bnj1373.1 |  | 
						
							| 2 |  | bnj1373.2 |  | 
						
							| 3 |  | bnj1373.3 |  | 
						
							| 4 |  | bnj1373.4 |  | 
						
							| 5 |  | bnj1373.5 | Could not format  ( ta' <-> [. y / x ]. ta ) : No typesetting found for |- ( ta' <-> [. y / x ]. ta ) with typecode |- | 
						
							| 6 | 1 | bnj1309 |  | 
						
							| 7 | 3 6 | bnj1307 |  | 
						
							| 8 | 7 | bnj1351 |  | 
						
							| 9 | 8 | nf5i |  | 
						
							| 10 |  | sneq |  | 
						
							| 11 |  | bnj1318 |  | 
						
							| 12 | 10 11 | uneq12d |  | 
						
							| 13 | 12 | eqeq2d |  | 
						
							| 14 | 13 | anbi2d |  | 
						
							| 15 | 4 14 | bitrid |  | 
						
							| 16 | 9 15 | sbciegf |  | 
						
							| 17 | 16 | elv |  | 
						
							| 18 | 5 17 | bitri | Could not format  ( ta' <-> ( f e. C /\ dom f = ( { y } u. _trCl ( y , A , R ) ) ) ) : No typesetting found for |- ( ta' <-> ( f e. C /\ dom f = ( { y } u. _trCl ( y , A , R ) ) ) ) with typecode |- |