| Step | Hyp | Ref | Expression | 
						
							| 1 |  | nvvop.1 |  | 
						
							| 2 |  | nvvop.2 |  | 
						
							| 3 |  | nvvop.4 |  | 
						
							| 4 |  | vcrel |  | 
						
							| 5 |  | nvss |  | 
						
							| 6 |  | eqid |  | 
						
							| 7 | 1 6 | nvop2 |  | 
						
							| 8 | 7 | eleq1d |  | 
						
							| 9 | 8 | ibi |  | 
						
							| 10 | 5 9 | sselid |  | 
						
							| 11 |  | opelxp1 |  | 
						
							| 12 | 10 11 | syl |  | 
						
							| 13 |  | 1st2nd |  | 
						
							| 14 | 4 12 13 | sylancr |  | 
						
							| 15 | 2 | vafval |  | 
						
							| 16 | 1 | fveq2i |  | 
						
							| 17 | 15 16 | eqtr4i |  | 
						
							| 18 | 3 | smfval |  | 
						
							| 19 | 1 | fveq2i |  | 
						
							| 20 | 18 19 | eqtr4i |  | 
						
							| 21 | 17 20 | opeq12i |  | 
						
							| 22 | 14 21 | eqtr4di |  |