Metamath Proof Explorer


Theorem evlsmaprhm

Description: The function F mapping polynomials p to their subring evaluation at a given point X is a ring homomorphism. Compare evls1maprhm . (Contributed by SN, 12-Mar-2025)

Ref Expression
Hypotheses evlsmaprhm.q 𝑄 = ( ( 𝐼 evalSub 𝑅 ) ‘ 𝑆 )
evlsmaprhm.p 𝑃 = ( 𝐼 mPoly 𝑈 )
evlsmaprhm.u 𝑈 = ( 𝑅s 𝑆 )
evlsmaprhm.b 𝐵 = ( Base ‘ 𝑃 )
evlsmaprhm.k 𝐾 = ( Base ‘ 𝑅 )
evlsmaprhm.f 𝐹 = ( 𝑝𝐵 ↦ ( ( 𝑄𝑝 ) ‘ 𝐴 ) )
evlsmaprhm.i ( 𝜑𝐼𝑉 )
evlsmaprhm.r ( 𝜑𝑅 ∈ CRing )
evlsmaprhm.s ( 𝜑𝑆 ∈ ( SubRing ‘ 𝑅 ) )
evlsmaprhm.a ( 𝜑𝐴 ∈ ( 𝐾m 𝐼 ) )
Assertion evlsmaprhm ( 𝜑𝐹 ∈ ( 𝑃 RingHom 𝑅 ) )

Proof

Step Hyp Ref Expression
1 evlsmaprhm.q 𝑄 = ( ( 𝐼 evalSub 𝑅 ) ‘ 𝑆 )
2 evlsmaprhm.p 𝑃 = ( 𝐼 mPoly 𝑈 )
3 evlsmaprhm.u 𝑈 = ( 𝑅s 𝑆 )
4 evlsmaprhm.b 𝐵 = ( Base ‘ 𝑃 )
5 evlsmaprhm.k 𝐾 = ( Base ‘ 𝑅 )
6 evlsmaprhm.f 𝐹 = ( 𝑝𝐵 ↦ ( ( 𝑄𝑝 ) ‘ 𝐴 ) )
7 evlsmaprhm.i ( 𝜑𝐼𝑉 )
8 evlsmaprhm.r ( 𝜑𝑅 ∈ CRing )
9 evlsmaprhm.s ( 𝜑𝑆 ∈ ( SubRing ‘ 𝑅 ) )
10 evlsmaprhm.a ( 𝜑𝐴 ∈ ( 𝐾m 𝐼 ) )
11 eqid ( 1r𝑃 ) = ( 1r𝑃 )
12 eqid ( 1r𝑅 ) = ( 1r𝑅 )
13 eqid ( .r𝑃 ) = ( .r𝑃 )
14 eqid ( .r𝑅 ) = ( .r𝑅 )
15 3 subrgring ( 𝑆 ∈ ( SubRing ‘ 𝑅 ) → 𝑈 ∈ Ring )
16 9 15 syl ( 𝜑𝑈 ∈ Ring )
17 2 7 16 mplringd ( 𝜑𝑃 ∈ Ring )
18 8 crngringd ( 𝜑𝑅 ∈ Ring )
19 fveq2 ( 𝑝 = ( 1r𝑃 ) → ( 𝑄𝑝 ) = ( 𝑄 ‘ ( 1r𝑃 ) ) )
20 19 fveq1d ( 𝑝 = ( 1r𝑃 ) → ( ( 𝑄𝑝 ) ‘ 𝐴 ) = ( ( 𝑄 ‘ ( 1r𝑃 ) ) ‘ 𝐴 ) )
21 4 11 ringidcl ( 𝑃 ∈ Ring → ( 1r𝑃 ) ∈ 𝐵 )
22 17 21 syl ( 𝜑 → ( 1r𝑃 ) ∈ 𝐵 )
23 fvexd ( 𝜑 → ( ( 𝑄 ‘ ( 1r𝑃 ) ) ‘ 𝐴 ) ∈ V )
24 6 20 22 23 fvmptd3 ( 𝜑 → ( 𝐹 ‘ ( 1r𝑃 ) ) = ( ( 𝑄 ‘ ( 1r𝑃 ) ) ‘ 𝐴 ) )
25 eqid ( algSc ‘ 𝑃 ) = ( algSc ‘ 𝑃 )
26 eqid ( 1r𝑈 ) = ( 1r𝑈 )
27 2 25 26 11 7 16 mplascl1 ( 𝜑 → ( ( algSc ‘ 𝑃 ) ‘ ( 1r𝑈 ) ) = ( 1r𝑃 ) )
28 27 eqcomd ( 𝜑 → ( 1r𝑃 ) = ( ( algSc ‘ 𝑃 ) ‘ ( 1r𝑈 ) ) )
29 28 fveq2d ( 𝜑 → ( 𝑄 ‘ ( 1r𝑃 ) ) = ( 𝑄 ‘ ( ( algSc ‘ 𝑃 ) ‘ ( 1r𝑈 ) ) ) )
30 29 fveq1d ( 𝜑 → ( ( 𝑄 ‘ ( 1r𝑃 ) ) ‘ 𝐴 ) = ( ( 𝑄 ‘ ( ( algSc ‘ 𝑃 ) ‘ ( 1r𝑈 ) ) ) ‘ 𝐴 ) )
31 3 12 subrg1 ( 𝑆 ∈ ( SubRing ‘ 𝑅 ) → ( 1r𝑅 ) = ( 1r𝑈 ) )
32 9 31 syl ( 𝜑 → ( 1r𝑅 ) = ( 1r𝑈 ) )
33 12 subrg1cl ( 𝑆 ∈ ( SubRing ‘ 𝑅 ) → ( 1r𝑅 ) ∈ 𝑆 )
34 9 33 syl ( 𝜑 → ( 1r𝑅 ) ∈ 𝑆 )
35 32 34 eqeltrrd ( 𝜑 → ( 1r𝑈 ) ∈ 𝑆 )
36 1 2 3 5 4 25 7 8 9 35 10 evlsscaval ( 𝜑 → ( ( ( algSc ‘ 𝑃 ) ‘ ( 1r𝑈 ) ) ∈ 𝐵 ∧ ( ( 𝑄 ‘ ( ( algSc ‘ 𝑃 ) ‘ ( 1r𝑈 ) ) ) ‘ 𝐴 ) = ( 1r𝑈 ) ) )
37 36 simprd ( 𝜑 → ( ( 𝑄 ‘ ( ( algSc ‘ 𝑃 ) ‘ ( 1r𝑈 ) ) ) ‘ 𝐴 ) = ( 1r𝑈 ) )
38 37 32 eqtr4d ( 𝜑 → ( ( 𝑄 ‘ ( ( algSc ‘ 𝑃 ) ‘ ( 1r𝑈 ) ) ) ‘ 𝐴 ) = ( 1r𝑅 ) )
39 24 30 38 3eqtrd ( 𝜑 → ( 𝐹 ‘ ( 1r𝑃 ) ) = ( 1r𝑅 ) )
40 7 adantr ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → 𝐼𝑉 )
41 8 adantr ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → 𝑅 ∈ CRing )
42 9 adantr ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → 𝑆 ∈ ( SubRing ‘ 𝑅 ) )
43 10 adantr ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → 𝐴 ∈ ( 𝐾m 𝐼 ) )
44 simprl ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → 𝑞𝐵 )
45 eqidd ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → ( ( 𝑄𝑞 ) ‘ 𝐴 ) = ( ( 𝑄𝑞 ) ‘ 𝐴 ) )
46 44 45 jca ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → ( 𝑞𝐵 ∧ ( ( 𝑄𝑞 ) ‘ 𝐴 ) = ( ( 𝑄𝑞 ) ‘ 𝐴 ) ) )
47 simprr ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → 𝑟𝐵 )
48 eqidd ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → ( ( 𝑄𝑟 ) ‘ 𝐴 ) = ( ( 𝑄𝑟 ) ‘ 𝐴 ) )
49 47 48 jca ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → ( 𝑟𝐵 ∧ ( ( 𝑄𝑟 ) ‘ 𝐴 ) = ( ( 𝑄𝑟 ) ‘ 𝐴 ) ) )
50 1 2 3 5 4 40 41 42 43 46 49 13 14 evlsmulval ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → ( ( 𝑞 ( .r𝑃 ) 𝑟 ) ∈ 𝐵 ∧ ( ( 𝑄 ‘ ( 𝑞 ( .r𝑃 ) 𝑟 ) ) ‘ 𝐴 ) = ( ( ( 𝑄𝑞 ) ‘ 𝐴 ) ( .r𝑅 ) ( ( 𝑄𝑟 ) ‘ 𝐴 ) ) ) )
51 50 simprd ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → ( ( 𝑄 ‘ ( 𝑞 ( .r𝑃 ) 𝑟 ) ) ‘ 𝐴 ) = ( ( ( 𝑄𝑞 ) ‘ 𝐴 ) ( .r𝑅 ) ( ( 𝑄𝑟 ) ‘ 𝐴 ) ) )
52 fveq2 ( 𝑝 = ( 𝑞 ( .r𝑃 ) 𝑟 ) → ( 𝑄𝑝 ) = ( 𝑄 ‘ ( 𝑞 ( .r𝑃 ) 𝑟 ) ) )
53 52 fveq1d ( 𝑝 = ( 𝑞 ( .r𝑃 ) 𝑟 ) → ( ( 𝑄𝑝 ) ‘ 𝐴 ) = ( ( 𝑄 ‘ ( 𝑞 ( .r𝑃 ) 𝑟 ) ) ‘ 𝐴 ) )
54 17 adantr ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → 𝑃 ∈ Ring )
55 4 13 54 44 47 ringcld ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → ( 𝑞 ( .r𝑃 ) 𝑟 ) ∈ 𝐵 )
56 fvexd ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → ( ( 𝑄 ‘ ( 𝑞 ( .r𝑃 ) 𝑟 ) ) ‘ 𝐴 ) ∈ V )
57 6 53 55 56 fvmptd3 ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → ( 𝐹 ‘ ( 𝑞 ( .r𝑃 ) 𝑟 ) ) = ( ( 𝑄 ‘ ( 𝑞 ( .r𝑃 ) 𝑟 ) ) ‘ 𝐴 ) )
58 fveq2 ( 𝑝 = 𝑞 → ( 𝑄𝑝 ) = ( 𝑄𝑞 ) )
59 58 fveq1d ( 𝑝 = 𝑞 → ( ( 𝑄𝑝 ) ‘ 𝐴 ) = ( ( 𝑄𝑞 ) ‘ 𝐴 ) )
60 fvexd ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → ( ( 𝑄𝑞 ) ‘ 𝐴 ) ∈ V )
61 6 59 44 60 fvmptd3 ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → ( 𝐹𝑞 ) = ( ( 𝑄𝑞 ) ‘ 𝐴 ) )
62 fveq2 ( 𝑝 = 𝑟 → ( 𝑄𝑝 ) = ( 𝑄𝑟 ) )
63 62 fveq1d ( 𝑝 = 𝑟 → ( ( 𝑄𝑝 ) ‘ 𝐴 ) = ( ( 𝑄𝑟 ) ‘ 𝐴 ) )
64 fvexd ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → ( ( 𝑄𝑟 ) ‘ 𝐴 ) ∈ V )
65 6 63 47 64 fvmptd3 ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → ( 𝐹𝑟 ) = ( ( 𝑄𝑟 ) ‘ 𝐴 ) )
66 61 65 oveq12d ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → ( ( 𝐹𝑞 ) ( .r𝑅 ) ( 𝐹𝑟 ) ) = ( ( ( 𝑄𝑞 ) ‘ 𝐴 ) ( .r𝑅 ) ( ( 𝑄𝑟 ) ‘ 𝐴 ) ) )
67 51 57 66 3eqtr4d ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → ( 𝐹 ‘ ( 𝑞 ( .r𝑃 ) 𝑟 ) ) = ( ( 𝐹𝑞 ) ( .r𝑅 ) ( 𝐹𝑟 ) ) )
68 eqid ( +g𝑃 ) = ( +g𝑃 )
69 eqid ( +g𝑅 ) = ( +g𝑅 )
70 7 adantr ( ( 𝜑𝑝𝐵 ) → 𝐼𝑉 )
71 8 adantr ( ( 𝜑𝑝𝐵 ) → 𝑅 ∈ CRing )
72 9 adantr ( ( 𝜑𝑝𝐵 ) → 𝑆 ∈ ( SubRing ‘ 𝑅 ) )
73 simpr ( ( 𝜑𝑝𝐵 ) → 𝑝𝐵 )
74 10 adantr ( ( 𝜑𝑝𝐵 ) → 𝐴 ∈ ( 𝐾m 𝐼 ) )
75 1 2 3 4 5 70 71 72 73 74 evlscl ( ( 𝜑𝑝𝐵 ) → ( ( 𝑄𝑝 ) ‘ 𝐴 ) ∈ 𝐾 )
76 75 6 fmptd ( 𝜑𝐹 : 𝐵𝐾 )
77 1 2 3 5 4 40 41 42 43 46 49 68 69 evlsaddval ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → ( ( 𝑞 ( +g𝑃 ) 𝑟 ) ∈ 𝐵 ∧ ( ( 𝑄 ‘ ( 𝑞 ( +g𝑃 ) 𝑟 ) ) ‘ 𝐴 ) = ( ( ( 𝑄𝑞 ) ‘ 𝐴 ) ( +g𝑅 ) ( ( 𝑄𝑟 ) ‘ 𝐴 ) ) ) )
78 77 simprd ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → ( ( 𝑄 ‘ ( 𝑞 ( +g𝑃 ) 𝑟 ) ) ‘ 𝐴 ) = ( ( ( 𝑄𝑞 ) ‘ 𝐴 ) ( +g𝑅 ) ( ( 𝑄𝑟 ) ‘ 𝐴 ) ) )
79 fveq2 ( 𝑝 = ( 𝑞 ( +g𝑃 ) 𝑟 ) → ( 𝑄𝑝 ) = ( 𝑄 ‘ ( 𝑞 ( +g𝑃 ) 𝑟 ) ) )
80 79 fveq1d ( 𝑝 = ( 𝑞 ( +g𝑃 ) 𝑟 ) → ( ( 𝑄𝑝 ) ‘ 𝐴 ) = ( ( 𝑄 ‘ ( 𝑞 ( +g𝑃 ) 𝑟 ) ) ‘ 𝐴 ) )
81 17 ringgrpd ( 𝜑𝑃 ∈ Grp )
82 81 adantr ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → 𝑃 ∈ Grp )
83 4 68 82 44 47 grpcld ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → ( 𝑞 ( +g𝑃 ) 𝑟 ) ∈ 𝐵 )
84 fvexd ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → ( ( 𝑄 ‘ ( 𝑞 ( +g𝑃 ) 𝑟 ) ) ‘ 𝐴 ) ∈ V )
85 6 80 83 84 fvmptd3 ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → ( 𝐹 ‘ ( 𝑞 ( +g𝑃 ) 𝑟 ) ) = ( ( 𝑄 ‘ ( 𝑞 ( +g𝑃 ) 𝑟 ) ) ‘ 𝐴 ) )
86 61 65 oveq12d ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → ( ( 𝐹𝑞 ) ( +g𝑅 ) ( 𝐹𝑟 ) ) = ( ( ( 𝑄𝑞 ) ‘ 𝐴 ) ( +g𝑅 ) ( ( 𝑄𝑟 ) ‘ 𝐴 ) ) )
87 78 85 86 3eqtr4d ( ( 𝜑 ∧ ( 𝑞𝐵𝑟𝐵 ) ) → ( 𝐹 ‘ ( 𝑞 ( +g𝑃 ) 𝑟 ) ) = ( ( 𝐹𝑞 ) ( +g𝑅 ) ( 𝐹𝑟 ) ) )
88 4 11 12 13 14 17 18 39 67 5 68 69 76 87 isrhmd ( 𝜑𝐹 ∈ ( 𝑃 RingHom 𝑅 ) )