| Step | Hyp | Ref | Expression | 
						
							| 1 |  | cnnvs.6 |  |-  U = <. <. + , x. >. , abs >. | 
						
							| 2 |  | eqid |  |-  ( .sOLD ` U ) = ( .sOLD ` U ) | 
						
							| 3 | 2 | smfval |  |-  ( .sOLD ` U ) = ( 2nd ` ( 1st ` U ) ) | 
						
							| 4 | 1 | fveq2i |  |-  ( 1st ` U ) = ( 1st ` <. <. + , x. >. , abs >. ) | 
						
							| 5 |  | opex |  |-  <. + , x. >. e. _V | 
						
							| 6 |  | absf |  |-  abs : CC --> RR | 
						
							| 7 |  | cnex |  |-  CC e. _V | 
						
							| 8 |  | fex |  |-  ( ( abs : CC --> RR /\ CC e. _V ) -> abs e. _V ) | 
						
							| 9 | 6 7 8 | mp2an |  |-  abs e. _V | 
						
							| 10 | 5 9 | op1st |  |-  ( 1st ` <. <. + , x. >. , abs >. ) = <. + , x. >. | 
						
							| 11 | 4 10 | eqtri |  |-  ( 1st ` U ) = <. + , x. >. | 
						
							| 12 | 11 | fveq2i |  |-  ( 2nd ` ( 1st ` U ) ) = ( 2nd ` <. + , x. >. ) | 
						
							| 13 |  | addex |  |-  + e. _V | 
						
							| 14 |  | mulex |  |-  x. e. _V | 
						
							| 15 | 13 14 | op2nd |  |-  ( 2nd ` <. + , x. >. ) = x. | 
						
							| 16 | 3 12 15 | 3eqtrri |  |-  x. = ( .sOLD ` U ) |