Metamath Proof Explorer


Theorem imasmgm2

Description: The image structure of a unital magma is a unital magma. (Contributed by Thierry Arnoux, 31-Aug-2026)

Ref Expression
Hypotheses imasmgm.u ( 𝜑𝑈 = ( 𝐹s 𝑅 ) )
imasmgm.v ( 𝜑𝑉 = ( Base ‘ 𝑅 ) )
imasmgm.p + = ( +g𝑅 )
imasmgm.f ( 𝜑𝐹 : 𝑉onto𝐵 )
imasmgm.e ( ( 𝜑 ∧ ( 𝑎𝑉𝑏𝑉 ) ∧ ( 𝑝𝑉𝑞𝑉 ) ) → ( ( ( 𝐹𝑎 ) = ( 𝐹𝑝 ) ∧ ( 𝐹𝑏 ) = ( 𝐹𝑞 ) ) → ( 𝐹 ‘ ( 𝑎 + 𝑏 ) ) = ( 𝐹 ‘ ( 𝑝 + 𝑞 ) ) ) )
imasmgm2.r ( 𝜑𝑅𝑊 )
imasmgm2.1 ( ( 𝜑𝑥𝑉𝑦𝑉 ) → ( 𝑥 + 𝑦 ) ∈ 𝑉 )
imasmgm2.2 ( 𝜑0𝑉 )
imasmgm2.3 ( ( 𝜑𝑥𝑉 ) → ( 𝐹 ‘ ( 0 + 𝑥 ) ) = ( 𝐹𝑥 ) )
imasmgm2.4 ( ( 𝜑𝑥𝑉 ) → ( 𝐹 ‘ ( 𝑥 + 0 ) ) = ( 𝐹𝑥 ) )
Assertion imasmgm2 ( 𝜑 → ( 𝑈 ∈ Mgm ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) )

Proof

Step Hyp Ref Expression
1 imasmgm.u ( 𝜑𝑈 = ( 𝐹s 𝑅 ) )
2 imasmgm.v ( 𝜑𝑉 = ( Base ‘ 𝑅 ) )
3 imasmgm.p + = ( +g𝑅 )
4 imasmgm.f ( 𝜑𝐹 : 𝑉onto𝐵 )
5 imasmgm.e ( ( 𝜑 ∧ ( 𝑎𝑉𝑏𝑉 ) ∧ ( 𝑝𝑉𝑞𝑉 ) ) → ( ( ( 𝐹𝑎 ) = ( 𝐹𝑝 ) ∧ ( 𝐹𝑏 ) = ( 𝐹𝑞 ) ) → ( 𝐹 ‘ ( 𝑎 + 𝑏 ) ) = ( 𝐹 ‘ ( 𝑝 + 𝑞 ) ) ) )
6 imasmgm2.r ( 𝜑𝑅𝑊 )
7 imasmgm2.1 ( ( 𝜑𝑥𝑉𝑦𝑉 ) → ( 𝑥 + 𝑦 ) ∈ 𝑉 )
8 imasmgm2.2 ( 𝜑0𝑉 )
9 imasmgm2.3 ( ( 𝜑𝑥𝑉 ) → ( 𝐹 ‘ ( 0 + 𝑥 ) ) = ( 𝐹𝑥 ) )
10 imasmgm2.4 ( ( 𝜑𝑥𝑉 ) → ( 𝐹 ‘ ( 𝑥 + 0 ) ) = ( 𝐹𝑥 ) )
11 1 2 4 6 imasbas ( 𝜑𝐵 = ( Base ‘ 𝑈 ) )
12 ovex ( 𝐹s 𝑅 ) ∈ V
13 1 12 eqeltrdi ( 𝜑𝑈 ∈ V )
14 eqidd ( 𝜑 → ( +g𝑈 ) = ( +g𝑈 ) )
15 eqid ( +g𝑈 ) = ( +g𝑈 )
16 7 3expb ( ( 𝜑 ∧ ( 𝑥𝑉𝑦𝑉 ) ) → ( 𝑥 + 𝑦 ) ∈ 𝑉 )
17 16 caovclg ( ( 𝜑 ∧ ( 𝑝𝑉𝑞𝑉 ) ) → ( 𝑝 + 𝑞 ) ∈ 𝑉 )
18 4 5 1 2 6 3 15 17 imasaddf ( 𝜑 → ( +g𝑈 ) : ( 𝐵 × 𝐵 ) ⟶ 𝐵 )
19 18 fovcld ( ( 𝜑𝑢𝐵𝑣𝐵 ) → ( 𝑢 ( +g𝑈 ) 𝑣 ) ∈ 𝐵 )
20 11 13 14 19 ismgmd ( 𝜑𝑈 ∈ Mgm )
21 fof ( 𝐹 : 𝑉onto𝐵𝐹 : 𝑉𝐵 )
22 4 21 syl ( 𝜑𝐹 : 𝑉𝐵 )
23 22 8 ffvelcdmd ( 𝜑 → ( 𝐹0 ) ∈ 𝐵 )
24 forn ( 𝐹 : 𝑉onto𝐵 → ran 𝐹 = 𝐵 )
25 4 24 syl ( 𝜑 → ran 𝐹 = 𝐵 )
26 25 eleq2d ( 𝜑 → ( 𝑢 ∈ ran 𝐹𝑢𝐵 ) )
27 fofn ( 𝐹 : 𝑉onto𝐵𝐹 Fn 𝑉 )
28 fvelrnb ( 𝐹 Fn 𝑉 → ( 𝑢 ∈ ran 𝐹 ↔ ∃ 𝑥𝑉 ( 𝐹𝑥 ) = 𝑢 ) )
29 4 27 28 3syl ( 𝜑 → ( 𝑢 ∈ ran 𝐹 ↔ ∃ 𝑥𝑉 ( 𝐹𝑥 ) = 𝑢 ) )
30 26 29 bitr3d ( 𝜑 → ( 𝑢𝐵 ↔ ∃ 𝑥𝑉 ( 𝐹𝑥 ) = 𝑢 ) )
31 simpl ( ( 𝜑𝑥𝑉 ) → 𝜑 )
32 8 adantr ( ( 𝜑𝑥𝑉 ) → 0𝑉 )
33 simpr ( ( 𝜑𝑥𝑉 ) → 𝑥𝑉 )
34 4 5 1 2 6 3 15 imasaddval ( ( 𝜑0𝑉𝑥𝑉 ) → ( ( 𝐹0 ) ( +g𝑈 ) ( 𝐹𝑥 ) ) = ( 𝐹 ‘ ( 0 + 𝑥 ) ) )
35 31 32 33 34 syl3anc ( ( 𝜑𝑥𝑉 ) → ( ( 𝐹0 ) ( +g𝑈 ) ( 𝐹𝑥 ) ) = ( 𝐹 ‘ ( 0 + 𝑥 ) ) )
36 35 9 eqtrd ( ( 𝜑𝑥𝑉 ) → ( ( 𝐹0 ) ( +g𝑈 ) ( 𝐹𝑥 ) ) = ( 𝐹𝑥 ) )
37 oveq2 ( ( 𝐹𝑥 ) = 𝑢 → ( ( 𝐹0 ) ( +g𝑈 ) ( 𝐹𝑥 ) ) = ( ( 𝐹0 ) ( +g𝑈 ) 𝑢 ) )
38 id ( ( 𝐹𝑥 ) = 𝑢 → ( 𝐹𝑥 ) = 𝑢 )
39 37 38 eqeq12d ( ( 𝐹𝑥 ) = 𝑢 → ( ( ( 𝐹0 ) ( +g𝑈 ) ( 𝐹𝑥 ) ) = ( 𝐹𝑥 ) ↔ ( ( 𝐹0 ) ( +g𝑈 ) 𝑢 ) = 𝑢 ) )
40 36 39 syl5ibcom ( ( 𝜑𝑥𝑉 ) → ( ( 𝐹𝑥 ) = 𝑢 → ( ( 𝐹0 ) ( +g𝑈 ) 𝑢 ) = 𝑢 ) )
41 40 rexlimdva ( 𝜑 → ( ∃ 𝑥𝑉 ( 𝐹𝑥 ) = 𝑢 → ( ( 𝐹0 ) ( +g𝑈 ) 𝑢 ) = 𝑢 ) )
42 30 41 sylbid ( 𝜑 → ( 𝑢𝐵 → ( ( 𝐹0 ) ( +g𝑈 ) 𝑢 ) = 𝑢 ) )
43 42 imp ( ( 𝜑𝑢𝐵 ) → ( ( 𝐹0 ) ( +g𝑈 ) 𝑢 ) = 𝑢 )
44 4 5 1 2 6 3 15 imasaddval ( ( 𝜑𝑥𝑉0𝑉 ) → ( ( 𝐹𝑥 ) ( +g𝑈 ) ( 𝐹0 ) ) = ( 𝐹 ‘ ( 𝑥 + 0 ) ) )
45 32 44 mpd3an3 ( ( 𝜑𝑥𝑉 ) → ( ( 𝐹𝑥 ) ( +g𝑈 ) ( 𝐹0 ) ) = ( 𝐹 ‘ ( 𝑥 + 0 ) ) )
46 45 10 eqtrd ( ( 𝜑𝑥𝑉 ) → ( ( 𝐹𝑥 ) ( +g𝑈 ) ( 𝐹0 ) ) = ( 𝐹𝑥 ) )
47 oveq1 ( ( 𝐹𝑥 ) = 𝑢 → ( ( 𝐹𝑥 ) ( +g𝑈 ) ( 𝐹0 ) ) = ( 𝑢 ( +g𝑈 ) ( 𝐹0 ) ) )
48 47 38 eqeq12d ( ( 𝐹𝑥 ) = 𝑢 → ( ( ( 𝐹𝑥 ) ( +g𝑈 ) ( 𝐹0 ) ) = ( 𝐹𝑥 ) ↔ ( 𝑢 ( +g𝑈 ) ( 𝐹0 ) ) = 𝑢 ) )
49 46 48 syl5ibcom ( ( 𝜑𝑥𝑉 ) → ( ( 𝐹𝑥 ) = 𝑢 → ( 𝑢 ( +g𝑈 ) ( 𝐹0 ) ) = 𝑢 ) )
50 49 rexlimdva ( 𝜑 → ( ∃ 𝑥𝑉 ( 𝐹𝑥 ) = 𝑢 → ( 𝑢 ( +g𝑈 ) ( 𝐹0 ) ) = 𝑢 ) )
51 30 50 sylbid ( 𝜑 → ( 𝑢𝐵 → ( 𝑢 ( +g𝑈 ) ( 𝐹0 ) ) = 𝑢 ) )
52 51 imp ( ( 𝜑𝑢𝐵 ) → ( 𝑢 ( +g𝑈 ) ( 𝐹0 ) ) = 𝑢 )
53 11 14 23 43 52 grpidd ( 𝜑 → ( 𝐹0 ) = ( 0g𝑈 ) )
54 20 53 jca ( 𝜑 → ( 𝑈 ∈ Mgm ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) )