| Step | Hyp | Ref | Expression | 
						
							| 1 |  | tngbas.t |  | 
						
							| 2 |  | tngtset.2 |  | 
						
							| 3 |  | tngtset.3 |  | 
						
							| 4 |  | ovex |  | 
						
							| 5 |  | fvex |  | 
						
							| 6 |  | tsetid |  | 
						
							| 7 | 6 | setsid |  | 
						
							| 8 | 4 5 7 | mp2an |  | 
						
							| 9 |  | eqid |  | 
						
							| 10 | 1 9 | tngds |  | 
						
							| 11 | 2 10 | eqtr4id |  | 
						
							| 12 | 11 | adantl |  | 
						
							| 13 | 12 | fveq2d |  | 
						
							| 14 | 3 13 | eqtrid |  | 
						
							| 15 |  | eqid |  | 
						
							| 16 |  | eqid |  | 
						
							| 17 | 1 9 15 16 | tngval |  | 
						
							| 18 | 17 | fveq2d |  | 
						
							| 19 | 8 14 18 | 3eqtr4a |  |