| Step | Hyp | Ref | Expression | 
						
							| 1 |  | llnset.b |  | 
						
							| 2 |  | llnset.c |  | 
						
							| 3 |  | llnset.a |  | 
						
							| 4 |  | llnset.n |  | 
						
							| 5 |  | elex |  | 
						
							| 6 |  | fveq2 |  | 
						
							| 7 | 6 1 | eqtr4di |  | 
						
							| 8 |  | fveq2 |  | 
						
							| 9 | 8 3 | eqtr4di |  | 
						
							| 10 |  | fveq2 |  | 
						
							| 11 | 10 2 | eqtr4di |  | 
						
							| 12 | 11 | breqd |  | 
						
							| 13 | 9 12 | rexeqbidv |  | 
						
							| 14 | 7 13 | rabeqbidv |  | 
						
							| 15 |  | df-llines |  | 
						
							| 16 | 1 | fvexi |  | 
						
							| 17 | 16 | rabex |  | 
						
							| 18 | 14 15 17 | fvmpt |  | 
						
							| 19 | 4 18 | eqtrid |  | 
						
							| 20 | 5 19 | syl |  |