Metamath Proof Explorer


Theorem ressply10g

Description: A restricted polynomial algebra has the same group identity (zero polynomial). (Contributed by Thierry Arnoux, 20-Jan-2025)

Ref Expression
Hypotheses ressply.1 ⊢ S = Poly 1 ⁡ R
ressply.2 ⊢ H = R ↾ 𝑠 T
ressply.3 ⊢ U = Poly 1 ⁡ H
ressply.4 ⊢ B = Base U
ressply.5 ⊢ φ → T ∈ SubRing ⁡ R
ressply10g.6 ⊢ Z = 0 S
Assertion ressply10g ⊢ φ → Z = 0 U

Proof

Step Hyp Ref Expression
1 ressply.1 ⊢ S = Poly 1 ⁡ R
2 ressply.2 ⊢ H = R ↾ 𝑠 T
3 ressply.3 ⊢ U = Poly 1 ⁡ H
4 ressply.4 ⊢ B = Base U
5 ressply.5 ⊢ φ → T ∈ SubRing ⁡ R
6 ressply10g.6 ⊢ Z = 0 S
7 eqid ⊢ algSc ⁡ S = algSc ⁡ S
8 eqid ⊢ algSc ⁡ U = algSc ⁡ U
9 1 7 2 3 5 8 subrg1ascl ⊢ φ → algSc ⁡ U = algSc ⁡ S ↾ T
10 9 fveq1d ⊢ φ → algSc ⁡ U ⁡ 0 H = algSc ⁡ S ↾ T ⁡ 0 H
11 eqid ⊢ 0 H = 0 H
12 eqid ⊢ 0 U = 0 U
13 2 subrgring ⊢ T ∈ SubRing ⁡ R → H ∈ Ring
14 5 13 syl ⊢ φ → H ∈ Ring
15 3 8 11 12 14 ply1ascl0 ⊢ φ → algSc ⁡ U ⁡ 0 H = 0 U
16 eqid ⊢ 0 R = 0 R
17 2 16 subrg0 ⊢ T ∈ SubRing ⁡ R → 0 R = 0 H
18 5 17 syl ⊢ φ → 0 R = 0 H
19 subrgsubg ⊢ T ∈ SubRing ⁡ R → T ∈ SubGrp ⁡ R
20 16 subg0cl ⊢ T ∈ SubGrp ⁡ R → 0 R ∈ T
21 5 19 20 3syl ⊢ φ → 0 R ∈ T
22 18 21 eqeltrrd ⊢ φ → 0 H ∈ T
23 22 fvresd ⊢ φ → algSc ⁡ S ↾ T ⁡ 0 H = algSc ⁡ S ⁡ 0 H
24 10 15 23 3eqtr3d ⊢ φ → 0 U = algSc ⁡ S ⁡ 0 H
25 18 fveq2d ⊢ φ → algSc ⁡ S ⁡ 0 R = algSc ⁡ S ⁡ 0 H
26 subrgrcl ⊢ T ∈ SubRing ⁡ R → R ∈ Ring
27 5 26 syl ⊢ φ → R ∈ Ring
28 1 7 16 6 27 ply1ascl0 ⊢ φ → algSc ⁡ S ⁡ 0 R = Z
29 24 25 28 3eqtr2rd ⊢ φ → Z = 0 U