Metamath Proof Explorer


Theorem mpfconst

Description: Constants are multivariate polynomial functions. (Contributed by Mario Carneiro, 19-Mar-2015)

Ref Expression
Hypotheses mpfconst.b 𝐵 = ( Base ‘ 𝑆 )
mpfconst.q 𝑄 = ran ( ( 𝐼 evalSub 𝑆 ) ‘ 𝑅 )
mpfconst.i ( 𝜑𝐼𝑉 )
mpfconst.s ( 𝜑𝑆 ∈ CRing )
mpfconst.r ( 𝜑𝑅 ∈ ( SubRing ‘ 𝑆 ) )
mpfconst.x ( 𝜑𝑋𝑅 )
Assertion mpfconst ( 𝜑 → ( ( 𝐵m 𝐼 ) × { 𝑋 } ) ∈ 𝑄 )

Proof

Step Hyp Ref Expression
1 mpfconst.b 𝐵 = ( Base ‘ 𝑆 )
2 mpfconst.q 𝑄 = ran ( ( 𝐼 evalSub 𝑆 ) ‘ 𝑅 )
3 mpfconst.i ( 𝜑𝐼𝑉 )
4 mpfconst.s ( 𝜑𝑆 ∈ CRing )
5 mpfconst.r ( 𝜑𝑅 ∈ ( SubRing ‘ 𝑆 ) )
6 mpfconst.x ( 𝜑𝑋𝑅 )
7 eqid ( ( 𝐼 evalSub 𝑆 ) ‘ 𝑅 ) = ( ( 𝐼 evalSub 𝑆 ) ‘ 𝑅 )
8 eqid ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) = ( 𝐼 mPoly ( 𝑆s 𝑅 ) )
9 eqid ( 𝑆s 𝑅 ) = ( 𝑆s 𝑅 )
10 eqid ( algSc ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ) = ( algSc ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) )
11 7 8 9 1 10 3 4 5 6 evlssca ( 𝜑 → ( ( ( 𝐼 evalSub 𝑆 ) ‘ 𝑅 ) ‘ ( ( algSc ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ) ‘ 𝑋 ) ) = ( ( 𝐵m 𝐼 ) × { 𝑋 } ) )
12 eqid ( 𝑆s ( 𝐵m 𝐼 ) ) = ( 𝑆s ( 𝐵m 𝐼 ) )
13 7 8 9 12 1 evlsrhm ( ( 𝐼𝑉𝑆 ∈ CRing ∧ 𝑅 ∈ ( SubRing ‘ 𝑆 ) ) → ( ( 𝐼 evalSub 𝑆 ) ‘ 𝑅 ) ∈ ( ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) RingHom ( 𝑆s ( 𝐵m 𝐼 ) ) ) )
14 3 4 5 13 syl3anc ( 𝜑 → ( ( 𝐼 evalSub 𝑆 ) ‘ 𝑅 ) ∈ ( ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) RingHom ( 𝑆s ( 𝐵m 𝐼 ) ) ) )
15 eqid ( Base ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ) = ( Base ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) )
16 eqid ( Base ‘ ( 𝑆s ( 𝐵m 𝐼 ) ) ) = ( Base ‘ ( 𝑆s ( 𝐵m 𝐼 ) ) )
17 15 16 rhmf ( ( ( 𝐼 evalSub 𝑆 ) ‘ 𝑅 ) ∈ ( ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) RingHom ( 𝑆s ( 𝐵m 𝐼 ) ) ) → ( ( 𝐼 evalSub 𝑆 ) ‘ 𝑅 ) : ( Base ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ) ⟶ ( Base ‘ ( 𝑆s ( 𝐵m 𝐼 ) ) ) )
18 ffn ( ( ( 𝐼 evalSub 𝑆 ) ‘ 𝑅 ) : ( Base ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ) ⟶ ( Base ‘ ( 𝑆s ( 𝐵m 𝐼 ) ) ) → ( ( 𝐼 evalSub 𝑆 ) ‘ 𝑅 ) Fn ( Base ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ) )
19 14 17 18 3syl ( 𝜑 → ( ( 𝐼 evalSub 𝑆 ) ‘ 𝑅 ) Fn ( Base ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ) )
20 9 subrgring ( 𝑅 ∈ ( SubRing ‘ 𝑆 ) → ( 𝑆s 𝑅 ) ∈ Ring )
21 5 20 syl ( 𝜑 → ( 𝑆s 𝑅 ) ∈ Ring )
22 eqid ( Scalar ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ) = ( Scalar ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) )
23 8 mplring ( ( 𝐼𝑉 ∧ ( 𝑆s 𝑅 ) ∈ Ring ) → ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ∈ Ring )
24 8 mpllmod ( ( 𝐼𝑉 ∧ ( 𝑆s 𝑅 ) ∈ Ring ) → ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ∈ LMod )
25 eqid ( Base ‘ ( Scalar ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ) ) = ( Base ‘ ( Scalar ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ) )
26 10 22 23 24 25 15 asclf ( ( 𝐼𝑉 ∧ ( 𝑆s 𝑅 ) ∈ Ring ) → ( algSc ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ) : ( Base ‘ ( Scalar ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ) ) ⟶ ( Base ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ) )
27 3 21 26 syl2anc ( 𝜑 → ( algSc ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ) : ( Base ‘ ( Scalar ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ) ) ⟶ ( Base ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ) )
28 1 subrgss ( 𝑅 ∈ ( SubRing ‘ 𝑆 ) → 𝑅𝐵 )
29 9 1 ressbas2 ( 𝑅𝐵𝑅 = ( Base ‘ ( 𝑆s 𝑅 ) ) )
30 5 28 29 3syl ( 𝜑𝑅 = ( Base ‘ ( 𝑆s 𝑅 ) ) )
31 ovexd ( 𝜑 → ( 𝑆s 𝑅 ) ∈ V )
32 8 3 31 mplsca ( 𝜑 → ( 𝑆s 𝑅 ) = ( Scalar ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ) )
33 32 fveq2d ( 𝜑 → ( Base ‘ ( 𝑆s 𝑅 ) ) = ( Base ‘ ( Scalar ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ) ) )
34 30 33 eqtrd ( 𝜑𝑅 = ( Base ‘ ( Scalar ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ) ) )
35 6 34 eleqtrd ( 𝜑𝑋 ∈ ( Base ‘ ( Scalar ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ) ) )
36 27 35 ffvelrnd ( 𝜑 → ( ( algSc ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ) ‘ 𝑋 ) ∈ ( Base ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ) )
37 fnfvelrn ( ( ( ( 𝐼 evalSub 𝑆 ) ‘ 𝑅 ) Fn ( Base ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ) ∧ ( ( algSc ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ) ‘ 𝑋 ) ∈ ( Base ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ) ) → ( ( ( 𝐼 evalSub 𝑆 ) ‘ 𝑅 ) ‘ ( ( algSc ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ) ‘ 𝑋 ) ) ∈ ran ( ( 𝐼 evalSub 𝑆 ) ‘ 𝑅 ) )
38 19 36 37 syl2anc ( 𝜑 → ( ( ( 𝐼 evalSub 𝑆 ) ‘ 𝑅 ) ‘ ( ( algSc ‘ ( 𝐼 mPoly ( 𝑆s 𝑅 ) ) ) ‘ 𝑋 ) ) ∈ ran ( ( 𝐼 evalSub 𝑆 ) ‘ 𝑅 ) )
39 11 38 eqeltrrd ( 𝜑 → ( ( 𝐵m 𝐼 ) × { 𝑋 } ) ∈ ran ( ( 𝐼 evalSub 𝑆 ) ‘ 𝑅 ) )
40 39 2 eleqtrrdi ( 𝜑 → ( ( 𝐵m 𝐼 ) × { 𝑋 } ) ∈ 𝑄 )