| Step | Hyp | Ref | Expression | 
						
							| 1 |  | dvmptadd.s |  |-  ( ph -> S e. { RR , CC } ) | 
						
							| 2 |  | dvmptadd.a |  |-  ( ( ph /\ x e. X ) -> A e. CC ) | 
						
							| 3 |  | dvmptadd.b |  |-  ( ( ph /\ x e. X ) -> B e. V ) | 
						
							| 4 |  | dvmptadd.da |  |-  ( ph -> ( S _D ( x e. X |-> A ) ) = ( x e. X |-> B ) ) | 
						
							| 5 |  | dvfg |  |-  ( S e. { RR , CC } -> ( S _D ( x e. X |-> A ) ) : dom ( S _D ( x e. X |-> A ) ) --> CC ) | 
						
							| 6 | 1 5 | syl |  |-  ( ph -> ( S _D ( x e. X |-> A ) ) : dom ( S _D ( x e. X |-> A ) ) --> CC ) | 
						
							| 7 | 4 | dmeqd |  |-  ( ph -> dom ( S _D ( x e. X |-> A ) ) = dom ( x e. X |-> B ) ) | 
						
							| 8 | 3 | ralrimiva |  |-  ( ph -> A. x e. X B e. V ) | 
						
							| 9 |  | dmmptg |  |-  ( A. x e. X B e. V -> dom ( x e. X |-> B ) = X ) | 
						
							| 10 | 8 9 | syl |  |-  ( ph -> dom ( x e. X |-> B ) = X ) | 
						
							| 11 | 7 10 | eqtrd |  |-  ( ph -> dom ( S _D ( x e. X |-> A ) ) = X ) | 
						
							| 12 | 11 | feq2d |  |-  ( ph -> ( ( S _D ( x e. X |-> A ) ) : dom ( S _D ( x e. X |-> A ) ) --> CC <-> ( S _D ( x e. X |-> A ) ) : X --> CC ) ) | 
						
							| 13 | 6 12 | mpbid |  |-  ( ph -> ( S _D ( x e. X |-> A ) ) : X --> CC ) | 
						
							| 14 | 4 | feq1d |  |-  ( ph -> ( ( S _D ( x e. X |-> A ) ) : X --> CC <-> ( x e. X |-> B ) : X --> CC ) ) | 
						
							| 15 | 13 14 | mpbid |  |-  ( ph -> ( x e. X |-> B ) : X --> CC ) | 
						
							| 16 | 15 | fvmptelcdm |  |-  ( ( ph /\ x e. X ) -> B e. CC ) |