| Step | Hyp | Ref | Expression | 
						
							| 1 |  | rrxval.r |  |-  H = ( RR^ ` I ) | 
						
							| 2 |  | rrxbase.b |  |-  B = ( Base ` H ) | 
						
							| 3 | 1 2 | rrxprds |  |-  ( I e. V -> H = ( toCPreHil ` ( ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) |`s B ) ) ) | 
						
							| 4 | 3 | fveq2d |  |-  ( I e. V -> ( .i ` H ) = ( .i ` ( toCPreHil ` ( ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) |`s B ) ) ) ) | 
						
							| 5 |  | eqid |  |-  ( toCPreHil ` ( ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) |`s B ) ) = ( toCPreHil ` ( ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) |`s B ) ) | 
						
							| 6 |  | eqid |  |-  ( .i ` ( ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) |`s B ) ) = ( .i ` ( ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) |`s B ) ) | 
						
							| 7 | 5 6 | tcphip |  |-  ( .i ` ( ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) |`s B ) ) = ( .i ` ( toCPreHil ` ( ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) |`s B ) ) ) | 
						
							| 8 | 2 | fvexi |  |-  B e. _V | 
						
							| 9 |  | eqid |  |-  ( ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) |`s B ) = ( ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) |`s B ) | 
						
							| 10 |  | eqid |  |-  ( .i ` ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) ) = ( .i ` ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) ) | 
						
							| 11 | 9 10 | ressip |  |-  ( B e. _V -> ( .i ` ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) ) = ( .i ` ( ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) |`s B ) ) ) | 
						
							| 12 | 8 11 | ax-mp |  |-  ( .i ` ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) ) = ( .i ` ( ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) |`s B ) ) | 
						
							| 13 |  | eqid |  |-  ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) = ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) | 
						
							| 14 |  | refld |  |-  RRfld e. Field | 
						
							| 15 | 14 | a1i |  |-  ( I e. V -> RRfld e. Field ) | 
						
							| 16 |  | snex |  |-  { ( ( subringAlg ` RRfld ) ` RR ) } e. _V | 
						
							| 17 |  | xpexg |  |-  ( ( I e. V /\ { ( ( subringAlg ` RRfld ) ` RR ) } e. _V ) -> ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) e. _V ) | 
						
							| 18 | 16 17 | mpan2 |  |-  ( I e. V -> ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) e. _V ) | 
						
							| 19 |  | eqid |  |-  ( Base ` ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) ) = ( Base ` ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) ) | 
						
							| 20 |  | fvex |  |-  ( ( subringAlg ` RRfld ) ` RR ) e. _V | 
						
							| 21 | 20 | snnz |  |-  { ( ( subringAlg ` RRfld ) ` RR ) } =/= (/) | 
						
							| 22 |  | dmxp |  |-  ( { ( ( subringAlg ` RRfld ) ` RR ) } =/= (/) -> dom ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) = I ) | 
						
							| 23 | 21 22 | ax-mp |  |-  dom ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) = I | 
						
							| 24 | 23 | a1i |  |-  ( I e. V -> dom ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) = I ) | 
						
							| 25 | 13 15 18 19 24 10 | prdsip |  |-  ( I e. V -> ( .i ` ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) ) = ( f e. ( Base ` ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) ) , g e. ( Base ` ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) ) |-> ( RRfld gsum ( x e. I |-> ( ( f ` x ) ( .i ` ( ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ` x ) ) ( g ` x ) ) ) ) ) ) | 
						
							| 26 | 13 15 18 19 24 | prdsbas |  |-  ( I e. V -> ( Base ` ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) ) = X_ x e. I ( Base ` ( ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ` x ) ) ) | 
						
							| 27 |  | eqidd |  |-  ( x e. I -> ( ( subringAlg ` RRfld ) ` RR ) = ( ( subringAlg ` RRfld ) ` RR ) ) | 
						
							| 28 |  | rebase |  |-  RR = ( Base ` RRfld ) | 
						
							| 29 | 28 | eqimssi |  |-  RR C_ ( Base ` RRfld ) | 
						
							| 30 | 29 | a1i |  |-  ( x e. I -> RR C_ ( Base ` RRfld ) ) | 
						
							| 31 | 27 30 | srabase |  |-  ( x e. I -> ( Base ` RRfld ) = ( Base ` ( ( subringAlg ` RRfld ) ` RR ) ) ) | 
						
							| 32 | 28 | a1i |  |-  ( x e. I -> RR = ( Base ` RRfld ) ) | 
						
							| 33 | 20 | fvconst2 |  |-  ( x e. I -> ( ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ` x ) = ( ( subringAlg ` RRfld ) ` RR ) ) | 
						
							| 34 | 33 | fveq2d |  |-  ( x e. I -> ( Base ` ( ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ` x ) ) = ( Base ` ( ( subringAlg ` RRfld ) ` RR ) ) ) | 
						
							| 35 | 31 32 34 | 3eqtr4rd |  |-  ( x e. I -> ( Base ` ( ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ` x ) ) = RR ) | 
						
							| 36 | 35 | adantl |  |-  ( ( I e. V /\ x e. I ) -> ( Base ` ( ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ` x ) ) = RR ) | 
						
							| 37 | 36 | ixpeq2dva |  |-  ( I e. V -> X_ x e. I ( Base ` ( ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ` x ) ) = X_ x e. I RR ) | 
						
							| 38 |  | reex |  |-  RR e. _V | 
						
							| 39 |  | ixpconstg |  |-  ( ( I e. V /\ RR e. _V ) -> X_ x e. I RR = ( RR ^m I ) ) | 
						
							| 40 | 38 39 | mpan2 |  |-  ( I e. V -> X_ x e. I RR = ( RR ^m I ) ) | 
						
							| 41 | 26 37 40 | 3eqtrd |  |-  ( I e. V -> ( Base ` ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) ) = ( RR ^m I ) ) | 
						
							| 42 |  | remulr |  |-  x. = ( .r ` RRfld ) | 
						
							| 43 | 33 30 | sraip |  |-  ( x e. I -> ( .r ` RRfld ) = ( .i ` ( ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ` x ) ) ) | 
						
							| 44 | 42 43 | eqtr2id |  |-  ( x e. I -> ( .i ` ( ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ` x ) ) = x. ) | 
						
							| 45 | 44 | oveqd |  |-  ( x e. I -> ( ( f ` x ) ( .i ` ( ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ` x ) ) ( g ` x ) ) = ( ( f ` x ) x. ( g ` x ) ) ) | 
						
							| 46 | 45 | mpteq2ia |  |-  ( x e. I |-> ( ( f ` x ) ( .i ` ( ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ` x ) ) ( g ` x ) ) ) = ( x e. I |-> ( ( f ` x ) x. ( g ` x ) ) ) | 
						
							| 47 | 46 | a1i |  |-  ( I e. V -> ( x e. I |-> ( ( f ` x ) ( .i ` ( ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ` x ) ) ( g ` x ) ) ) = ( x e. I |-> ( ( f ` x ) x. ( g ` x ) ) ) ) | 
						
							| 48 | 47 | oveq2d |  |-  ( I e. V -> ( RRfld gsum ( x e. I |-> ( ( f ` x ) ( .i ` ( ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ` x ) ) ( g ` x ) ) ) ) = ( RRfld gsum ( x e. I |-> ( ( f ` x ) x. ( g ` x ) ) ) ) ) | 
						
							| 49 | 41 41 48 | mpoeq123dv |  |-  ( I e. V -> ( f e. ( Base ` ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) ) , g e. ( Base ` ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) ) |-> ( RRfld gsum ( x e. I |-> ( ( f ` x ) ( .i ` ( ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ` x ) ) ( g ` x ) ) ) ) ) = ( f e. ( RR ^m I ) , g e. ( RR ^m I ) |-> ( RRfld gsum ( x e. I |-> ( ( f ` x ) x. ( g ` x ) ) ) ) ) ) | 
						
							| 50 | 25 49 | eqtrd |  |-  ( I e. V -> ( .i ` ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) ) = ( f e. ( RR ^m I ) , g e. ( RR ^m I ) |-> ( RRfld gsum ( x e. I |-> ( ( f ` x ) x. ( g ` x ) ) ) ) ) ) | 
						
							| 51 | 12 50 | eqtr3id |  |-  ( I e. V -> ( .i ` ( ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) |`s B ) ) = ( f e. ( RR ^m I ) , g e. ( RR ^m I ) |-> ( RRfld gsum ( x e. I |-> ( ( f ` x ) x. ( g ` x ) ) ) ) ) ) | 
						
							| 52 | 7 51 | eqtr3id |  |-  ( I e. V -> ( .i ` ( toCPreHil ` ( ( RRfld Xs_ ( I X. { ( ( subringAlg ` RRfld ) ` RR ) } ) ) |`s B ) ) ) = ( f e. ( RR ^m I ) , g e. ( RR ^m I ) |-> ( RRfld gsum ( x e. I |-> ( ( f ` x ) x. ( g ` x ) ) ) ) ) ) | 
						
							| 53 | 4 52 | eqtr2d |  |-  ( I e. V -> ( f e. ( RR ^m I ) , g e. ( RR ^m I ) |-> ( RRfld gsum ( x e. I |-> ( ( f ` x ) x. ( g ` x ) ) ) ) ) = ( .i ` H ) ) |