Metamath Proof Explorer


Theorem evl1fpws

Description: Evaluation of a univariate polynomial as a function in a power series. (Contributed by Thierry Arnoux, 23-Jan-2025)

Ref Expression
Hypotheses evl1fpws.q
|- O = ( eval1 ` R )
evl1fpws.w
|- W = ( Poly1 ` R )
evl1fpws.b
|- B = ( Base ` R )
evl1fpws.u
|- U = ( Base ` W )
evl1fpws.s
|- ( ph -> R e. CRing )
evl1fpws.y
|- ( ph -> M e. U )
evl1fpws.1
|- .x. = ( .r ` R )
evl1fpws.2
|- .^ = ( .g ` ( mulGrp ` R ) )
evl1fpws.a
|- A = ( coe1 ` M )
Assertion evl1fpws
|- ( ph -> ( O ` M ) = ( x e. B |-> ( R gsum ( k e. NN0 |-> ( ( A ` k ) .x. ( k .^ x ) ) ) ) ) )

Proof

Step Hyp Ref Expression
1 evl1fpws.q
 |-  O = ( eval1 ` R )
2 evl1fpws.w
 |-  W = ( Poly1 ` R )
3 evl1fpws.b
 |-  B = ( Base ` R )
4 evl1fpws.u
 |-  U = ( Base ` W )
5 evl1fpws.s
 |-  ( ph -> R e. CRing )
6 evl1fpws.y
 |-  ( ph -> M e. U )
7 evl1fpws.1
 |-  .x. = ( .r ` R )
8 evl1fpws.2
 |-  .^ = ( .g ` ( mulGrp ` R ) )
9 evl1fpws.a
 |-  A = ( coe1 ` M )
10 1 3 evl1fval1
 |-  O = ( R evalSub1 B )
11 10 fveq1i
 |-  ( O ` M ) = ( ( R evalSub1 B ) ` M )
12 eqid
 |-  ( R evalSub1 B ) = ( R evalSub1 B )
13 eqid
 |-  ( Poly1 ` ( R |`s B ) ) = ( Poly1 ` ( R |`s B ) )
14 eqid
 |-  ( R |`s B ) = ( R |`s B )
15 eqid
 |-  ( Base ` ( Poly1 ` ( R |`s B ) ) ) = ( Base ` ( Poly1 ` ( R |`s B ) ) )
16 5 crngringd
 |-  ( ph -> R e. Ring )
17 3 subrgid
 |-  ( R e. Ring -> B e. ( SubRing ` R ) )
18 16 17 syl
 |-  ( ph -> B e. ( SubRing ` R ) )
19 3 ressid
 |-  ( R e. CRing -> ( R |`s B ) = R )
20 5 19 syl
 |-  ( ph -> ( R |`s B ) = R )
21 20 fveq2d
 |-  ( ph -> ( Poly1 ` ( R |`s B ) ) = ( Poly1 ` R ) )
22 21 2 eqtr4di
 |-  ( ph -> ( Poly1 ` ( R |`s B ) ) = W )
23 22 fveq2d
 |-  ( ph -> ( Base ` ( Poly1 ` ( R |`s B ) ) ) = ( Base ` W ) )
24 23 4 eqtr4di
 |-  ( ph -> ( Base ` ( Poly1 ` ( R |`s B ) ) ) = U )
25 6 24 eleqtrrd
 |-  ( ph -> M e. ( Base ` ( Poly1 ` ( R |`s B ) ) ) )
26 12 3 13 14 15 5 18 25 7 8 9 evls1fpws
 |-  ( ph -> ( ( R evalSub1 B ) ` M ) = ( x e. B |-> ( R gsum ( k e. NN0 |-> ( ( A ` k ) .x. ( k .^ x ) ) ) ) ) )
27 11 26 eqtrid
 |-  ( ph -> ( O ` M ) = ( x e. B |-> ( R gsum ( k e. NN0 |-> ( ( A ` k ) .x. ( k .^ x ) ) ) ) ) )