Metamath Proof Explorer


Theorem imasabl

Description: The image structure of an abelian group is an abelian group ( imasgrp analog). (Contributed by AV, 22-Feb-2025)

Ref Expression
Hypotheses imasabl.u ( 𝜑𝑈 = ( 𝐹s 𝑅 ) )
imasabl.v ( 𝜑𝑉 = ( Base ‘ 𝑅 ) )
imasabl.p ( 𝜑+ = ( +g𝑅 ) )
imasabl.f ( 𝜑𝐹 : 𝑉onto𝐵 )
imasabl.e ( ( 𝜑 ∧ ( 𝑎𝑉𝑏𝑉 ) ∧ ( 𝑝𝑉𝑞𝑉 ) ) → ( ( ( 𝐹𝑎 ) = ( 𝐹𝑝 ) ∧ ( 𝐹𝑏 ) = ( 𝐹𝑞 ) ) → ( 𝐹 ‘ ( 𝑎 + 𝑏 ) ) = ( 𝐹 ‘ ( 𝑝 + 𝑞 ) ) ) )
imasabl.r ( 𝜑𝑅 ∈ Abel )
imasabl.z 0 = ( 0g𝑅 )
Assertion imasabl ( 𝜑 → ( 𝑈 ∈ Abel ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) )

Proof

Step Hyp Ref Expression
1 imasabl.u ( 𝜑𝑈 = ( 𝐹s 𝑅 ) )
2 imasabl.v ( 𝜑𝑉 = ( Base ‘ 𝑅 ) )
3 imasabl.p ( 𝜑+ = ( +g𝑅 ) )
4 imasabl.f ( 𝜑𝐹 : 𝑉onto𝐵 )
5 imasabl.e ( ( 𝜑 ∧ ( 𝑎𝑉𝑏𝑉 ) ∧ ( 𝑝𝑉𝑞𝑉 ) ) → ( ( ( 𝐹𝑎 ) = ( 𝐹𝑝 ) ∧ ( 𝐹𝑏 ) = ( 𝐹𝑞 ) ) → ( 𝐹 ‘ ( 𝑎 + 𝑏 ) ) = ( 𝐹 ‘ ( 𝑝 + 𝑞 ) ) ) )
6 imasabl.r ( 𝜑𝑅 ∈ Abel )
7 imasabl.z 0 = ( 0g𝑅 )
8 6 ablgrpd ( 𝜑𝑅 ∈ Grp )
9 1 2 3 4 5 8 7 imasgrp ( 𝜑 → ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) )
10 1 2 4 6 imasbas ( 𝜑𝐵 = ( Base ‘ 𝑈 ) )
11 10 eqcomd ( 𝜑 → ( Base ‘ 𝑈 ) = 𝐵 )
12 11 eleq2d ( 𝜑 → ( 𝑥 ∈ ( Base ‘ 𝑈 ) ↔ 𝑥𝐵 ) )
13 11 eleq2d ( 𝜑 → ( 𝑦 ∈ ( Base ‘ 𝑈 ) ↔ 𝑦𝐵 ) )
14 12 13 anbi12d ( 𝜑 → ( ( 𝑥 ∈ ( Base ‘ 𝑈 ) ∧ 𝑦 ∈ ( Base ‘ 𝑈 ) ) ↔ ( 𝑥𝐵𝑦𝐵 ) ) )
15 14 adantr ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) → ( ( 𝑥 ∈ ( Base ‘ 𝑈 ) ∧ 𝑦 ∈ ( Base ‘ 𝑈 ) ) ↔ ( 𝑥𝐵𝑦𝐵 ) ) )
16 foelcdmi ( ( 𝐹 : 𝑉onto𝐵𝑥𝐵 ) → ∃ 𝑎𝑉 ( 𝐹𝑎 ) = 𝑥 )
17 16 ex ( 𝐹 : 𝑉onto𝐵 → ( 𝑥𝐵 → ∃ 𝑎𝑉 ( 𝐹𝑎 ) = 𝑥 ) )
18 foelcdmi ( ( 𝐹 : 𝑉onto𝐵𝑦𝐵 ) → ∃ 𝑏𝑉 ( 𝐹𝑏 ) = 𝑦 )
19 18 ex ( 𝐹 : 𝑉onto𝐵 → ( 𝑦𝐵 → ∃ 𝑏𝑉 ( 𝐹𝑏 ) = 𝑦 ) )
20 17 19 anim12d ( 𝐹 : 𝑉onto𝐵 → ( ( 𝑥𝐵𝑦𝐵 ) → ( ∃ 𝑎𝑉 ( 𝐹𝑎 ) = 𝑥 ∧ ∃ 𝑏𝑉 ( 𝐹𝑏 ) = 𝑦 ) ) )
21 4 20 syl ( 𝜑 → ( ( 𝑥𝐵𝑦𝐵 ) → ( ∃ 𝑎𝑉 ( 𝐹𝑎 ) = 𝑥 ∧ ∃ 𝑏𝑉 ( 𝐹𝑏 ) = 𝑦 ) ) )
22 21 adantr ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) → ( ( 𝑥𝐵𝑦𝐵 ) → ( ∃ 𝑎𝑉 ( 𝐹𝑎 ) = 𝑥 ∧ ∃ 𝑏𝑉 ( 𝐹𝑏 ) = 𝑦 ) ) )
23 6 ad3antrrr ( ( ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) ∧ 𝑎𝑉 ) ∧ 𝑏𝑉 ) → 𝑅 ∈ Abel )
24 2 eleq2d ( 𝜑 → ( 𝑎𝑉𝑎 ∈ ( Base ‘ 𝑅 ) ) )
25 24 biimpd ( 𝜑 → ( 𝑎𝑉𝑎 ∈ ( Base ‘ 𝑅 ) ) )
26 25 adantr ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) → ( 𝑎𝑉𝑎 ∈ ( Base ‘ 𝑅 ) ) )
27 26 imp ( ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) ∧ 𝑎𝑉 ) → 𝑎 ∈ ( Base ‘ 𝑅 ) )
28 27 adantr ( ( ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) ∧ 𝑎𝑉 ) ∧ 𝑏𝑉 ) → 𝑎 ∈ ( Base ‘ 𝑅 ) )
29 2 eleq2d ( 𝜑 → ( 𝑏𝑉𝑏 ∈ ( Base ‘ 𝑅 ) ) )
30 29 biimpd ( 𝜑 → ( 𝑏𝑉𝑏 ∈ ( Base ‘ 𝑅 ) ) )
31 30 adantr ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) → ( 𝑏𝑉𝑏 ∈ ( Base ‘ 𝑅 ) ) )
32 31 adantr ( ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) ∧ 𝑎𝑉 ) → ( 𝑏𝑉𝑏 ∈ ( Base ‘ 𝑅 ) ) )
33 32 imp ( ( ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) ∧ 𝑎𝑉 ) ∧ 𝑏𝑉 ) → 𝑏 ∈ ( Base ‘ 𝑅 ) )
34 eqid ( Base ‘ 𝑅 ) = ( Base ‘ 𝑅 )
35 eqid ( +g𝑅 ) = ( +g𝑅 )
36 34 35 ablcom ( ( 𝑅 ∈ Abel ∧ 𝑎 ∈ ( Base ‘ 𝑅 ) ∧ 𝑏 ∈ ( Base ‘ 𝑅 ) ) → ( 𝑎 ( +g𝑅 ) 𝑏 ) = ( 𝑏 ( +g𝑅 ) 𝑎 ) )
37 23 28 33 36 syl3anc ( ( ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) ∧ 𝑎𝑉 ) ∧ 𝑏𝑉 ) → ( 𝑎 ( +g𝑅 ) 𝑏 ) = ( 𝑏 ( +g𝑅 ) 𝑎 ) )
38 37 fveq2d ( ( ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) ∧ 𝑎𝑉 ) ∧ 𝑏𝑉 ) → ( 𝐹 ‘ ( 𝑎 ( +g𝑅 ) 𝑏 ) ) = ( 𝐹 ‘ ( 𝑏 ( +g𝑅 ) 𝑎 ) ) )
39 simplll ( ( ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) ∧ 𝑎𝑉 ) ∧ 𝑏𝑉 ) → 𝜑 )
40 simpr ( ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) ∧ 𝑎𝑉 ) → 𝑎𝑉 )
41 40 adantr ( ( ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) ∧ 𝑎𝑉 ) ∧ 𝑏𝑉 ) → 𝑎𝑉 )
42 simpr ( ( ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) ∧ 𝑎𝑉 ) ∧ 𝑏𝑉 ) → 𝑏𝑉 )
43 3 eqcomd ( 𝜑 → ( +g𝑅 ) = + )
44 43 oveqd ( 𝜑 → ( 𝑎 ( +g𝑅 ) 𝑏 ) = ( 𝑎 + 𝑏 ) )
45 44 fveq2d ( 𝜑 → ( 𝐹 ‘ ( 𝑎 ( +g𝑅 ) 𝑏 ) ) = ( 𝐹 ‘ ( 𝑎 + 𝑏 ) ) )
46 43 oveqd ( 𝜑 → ( 𝑝 ( +g𝑅 ) 𝑞 ) = ( 𝑝 + 𝑞 ) )
47 46 fveq2d ( 𝜑 → ( 𝐹 ‘ ( 𝑝 ( +g𝑅 ) 𝑞 ) ) = ( 𝐹 ‘ ( 𝑝 + 𝑞 ) ) )
48 45 47 eqeq12d ( 𝜑 → ( ( 𝐹 ‘ ( 𝑎 ( +g𝑅 ) 𝑏 ) ) = ( 𝐹 ‘ ( 𝑝 ( +g𝑅 ) 𝑞 ) ) ↔ ( 𝐹 ‘ ( 𝑎 + 𝑏 ) ) = ( 𝐹 ‘ ( 𝑝 + 𝑞 ) ) ) )
49 48 3ad2ant1 ( ( 𝜑 ∧ ( 𝑎𝑉𝑏𝑉 ) ∧ ( 𝑝𝑉𝑞𝑉 ) ) → ( ( 𝐹 ‘ ( 𝑎 ( +g𝑅 ) 𝑏 ) ) = ( 𝐹 ‘ ( 𝑝 ( +g𝑅 ) 𝑞 ) ) ↔ ( 𝐹 ‘ ( 𝑎 + 𝑏 ) ) = ( 𝐹 ‘ ( 𝑝 + 𝑞 ) ) ) )
50 5 49 sylibrd ( ( 𝜑 ∧ ( 𝑎𝑉𝑏𝑉 ) ∧ ( 𝑝𝑉𝑞𝑉 ) ) → ( ( ( 𝐹𝑎 ) = ( 𝐹𝑝 ) ∧ ( 𝐹𝑏 ) = ( 𝐹𝑞 ) ) → ( 𝐹 ‘ ( 𝑎 ( +g𝑅 ) 𝑏 ) ) = ( 𝐹 ‘ ( 𝑝 ( +g𝑅 ) 𝑞 ) ) ) )
51 eqid ( +g𝑈 ) = ( +g𝑈 )
52 4 50 1 2 6 35 51 imasaddval ( ( 𝜑𝑎𝑉𝑏𝑉 ) → ( ( 𝐹𝑎 ) ( +g𝑈 ) ( 𝐹𝑏 ) ) = ( 𝐹 ‘ ( 𝑎 ( +g𝑅 ) 𝑏 ) ) )
53 39 41 42 52 syl3anc ( ( ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) ∧ 𝑎𝑉 ) ∧ 𝑏𝑉 ) → ( ( 𝐹𝑎 ) ( +g𝑈 ) ( 𝐹𝑏 ) ) = ( 𝐹 ‘ ( 𝑎 ( +g𝑅 ) 𝑏 ) ) )
54 4 50 1 2 6 35 51 imasaddval ( ( 𝜑𝑏𝑉𝑎𝑉 ) → ( ( 𝐹𝑏 ) ( +g𝑈 ) ( 𝐹𝑎 ) ) = ( 𝐹 ‘ ( 𝑏 ( +g𝑅 ) 𝑎 ) ) )
55 39 42 41 54 syl3anc ( ( ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) ∧ 𝑎𝑉 ) ∧ 𝑏𝑉 ) → ( ( 𝐹𝑏 ) ( +g𝑈 ) ( 𝐹𝑎 ) ) = ( 𝐹 ‘ ( 𝑏 ( +g𝑅 ) 𝑎 ) ) )
56 38 53 55 3eqtr4d ( ( ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) ∧ 𝑎𝑉 ) ∧ 𝑏𝑉 ) → ( ( 𝐹𝑎 ) ( +g𝑈 ) ( 𝐹𝑏 ) ) = ( ( 𝐹𝑏 ) ( +g𝑈 ) ( 𝐹𝑎 ) ) )
57 56 adantr ( ( ( ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) ∧ 𝑎𝑉 ) ∧ 𝑏𝑉 ) ∧ ( ( 𝐹𝑏 ) = 𝑦 ∧ ( 𝐹𝑎 ) = 𝑥 ) ) → ( ( 𝐹𝑎 ) ( +g𝑈 ) ( 𝐹𝑏 ) ) = ( ( 𝐹𝑏 ) ( +g𝑈 ) ( 𝐹𝑎 ) ) )
58 oveq12 ( ( ( 𝐹𝑎 ) = 𝑥 ∧ ( 𝐹𝑏 ) = 𝑦 ) → ( ( 𝐹𝑎 ) ( +g𝑈 ) ( 𝐹𝑏 ) ) = ( 𝑥 ( +g𝑈 ) 𝑦 ) )
59 58 ancoms ( ( ( 𝐹𝑏 ) = 𝑦 ∧ ( 𝐹𝑎 ) = 𝑥 ) → ( ( 𝐹𝑎 ) ( +g𝑈 ) ( 𝐹𝑏 ) ) = ( 𝑥 ( +g𝑈 ) 𝑦 ) )
60 oveq12 ( ( ( 𝐹𝑏 ) = 𝑦 ∧ ( 𝐹𝑎 ) = 𝑥 ) → ( ( 𝐹𝑏 ) ( +g𝑈 ) ( 𝐹𝑎 ) ) = ( 𝑦 ( +g𝑈 ) 𝑥 ) )
61 59 60 eqeq12d ( ( ( 𝐹𝑏 ) = 𝑦 ∧ ( 𝐹𝑎 ) = 𝑥 ) → ( ( ( 𝐹𝑎 ) ( +g𝑈 ) ( 𝐹𝑏 ) ) = ( ( 𝐹𝑏 ) ( +g𝑈 ) ( 𝐹𝑎 ) ) ↔ ( 𝑥 ( +g𝑈 ) 𝑦 ) = ( 𝑦 ( +g𝑈 ) 𝑥 ) ) )
62 61 adantl ( ( ( ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) ∧ 𝑎𝑉 ) ∧ 𝑏𝑉 ) ∧ ( ( 𝐹𝑏 ) = 𝑦 ∧ ( 𝐹𝑎 ) = 𝑥 ) ) → ( ( ( 𝐹𝑎 ) ( +g𝑈 ) ( 𝐹𝑏 ) ) = ( ( 𝐹𝑏 ) ( +g𝑈 ) ( 𝐹𝑎 ) ) ↔ ( 𝑥 ( +g𝑈 ) 𝑦 ) = ( 𝑦 ( +g𝑈 ) 𝑥 ) ) )
63 57 62 mpbid ( ( ( ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) ∧ 𝑎𝑉 ) ∧ 𝑏𝑉 ) ∧ ( ( 𝐹𝑏 ) = 𝑦 ∧ ( 𝐹𝑎 ) = 𝑥 ) ) → ( 𝑥 ( +g𝑈 ) 𝑦 ) = ( 𝑦 ( +g𝑈 ) 𝑥 ) )
64 63 exp32 ( ( ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) ∧ 𝑎𝑉 ) ∧ 𝑏𝑉 ) → ( ( 𝐹𝑏 ) = 𝑦 → ( ( 𝐹𝑎 ) = 𝑥 → ( 𝑥 ( +g𝑈 ) 𝑦 ) = ( 𝑦 ( +g𝑈 ) 𝑥 ) ) ) )
65 64 rexlimdva ( ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) ∧ 𝑎𝑉 ) → ( ∃ 𝑏𝑉 ( 𝐹𝑏 ) = 𝑦 → ( ( 𝐹𝑎 ) = 𝑥 → ( 𝑥 ( +g𝑈 ) 𝑦 ) = ( 𝑦 ( +g𝑈 ) 𝑥 ) ) ) )
66 65 com23 ( ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) ∧ 𝑎𝑉 ) → ( ( 𝐹𝑎 ) = 𝑥 → ( ∃ 𝑏𝑉 ( 𝐹𝑏 ) = 𝑦 → ( 𝑥 ( +g𝑈 ) 𝑦 ) = ( 𝑦 ( +g𝑈 ) 𝑥 ) ) ) )
67 66 rexlimdva ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) → ( ∃ 𝑎𝑉 ( 𝐹𝑎 ) = 𝑥 → ( ∃ 𝑏𝑉 ( 𝐹𝑏 ) = 𝑦 → ( 𝑥 ( +g𝑈 ) 𝑦 ) = ( 𝑦 ( +g𝑈 ) 𝑥 ) ) ) )
68 67 impd ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) → ( ( ∃ 𝑎𝑉 ( 𝐹𝑎 ) = 𝑥 ∧ ∃ 𝑏𝑉 ( 𝐹𝑏 ) = 𝑦 ) → ( 𝑥 ( +g𝑈 ) 𝑦 ) = ( 𝑦 ( +g𝑈 ) 𝑥 ) ) )
69 22 68 syld ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) → ( ( 𝑥𝐵𝑦𝐵 ) → ( 𝑥 ( +g𝑈 ) 𝑦 ) = ( 𝑦 ( +g𝑈 ) 𝑥 ) ) )
70 15 69 sylbid ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) → ( ( 𝑥 ∈ ( Base ‘ 𝑈 ) ∧ 𝑦 ∈ ( Base ‘ 𝑈 ) ) → ( 𝑥 ( +g𝑈 ) 𝑦 ) = ( 𝑦 ( +g𝑈 ) 𝑥 ) ) )
71 70 imp ( ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) ∧ ( 𝑥 ∈ ( Base ‘ 𝑈 ) ∧ 𝑦 ∈ ( Base ‘ 𝑈 ) ) ) → ( 𝑥 ( +g𝑈 ) 𝑦 ) = ( 𝑦 ( +g𝑈 ) 𝑥 ) )
72 71 ralrimivva ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) → ∀ 𝑥 ∈ ( Base ‘ 𝑈 ) ∀ 𝑦 ∈ ( Base ‘ 𝑈 ) ( 𝑥 ( +g𝑈 ) 𝑦 ) = ( 𝑦 ( +g𝑈 ) 𝑥 ) )
73 simpr ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) → ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) )
74 72 73 jca ( ( 𝜑 ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) → ( ∀ 𝑥 ∈ ( Base ‘ 𝑈 ) ∀ 𝑦 ∈ ( Base ‘ 𝑈 ) ( 𝑥 ( +g𝑈 ) 𝑦 ) = ( 𝑦 ( +g𝑈 ) 𝑥 ) ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) )
75 9 74 mpdan ( 𝜑 → ( ∀ 𝑥 ∈ ( Base ‘ 𝑈 ) ∀ 𝑦 ∈ ( Base ‘ 𝑈 ) ( 𝑥 ( +g𝑈 ) 𝑦 ) = ( 𝑦 ( +g𝑈 ) 𝑥 ) ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) )
76 eqid ( Base ‘ 𝑈 ) = ( Base ‘ 𝑈 )
77 76 51 isabl2 ( 𝑈 ∈ Abel ↔ ( 𝑈 ∈ Grp ∧ ∀ 𝑥 ∈ ( Base ‘ 𝑈 ) ∀ 𝑦 ∈ ( Base ‘ 𝑈 ) ( 𝑥 ( +g𝑈 ) 𝑦 ) = ( 𝑦 ( +g𝑈 ) 𝑥 ) ) )
78 77 anbi1i ( ( 𝑈 ∈ Abel ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ↔ ( ( 𝑈 ∈ Grp ∧ ∀ 𝑥 ∈ ( Base ‘ 𝑈 ) ∀ 𝑦 ∈ ( Base ‘ 𝑈 ) ( 𝑥 ( +g𝑈 ) 𝑦 ) = ( 𝑦 ( +g𝑈 ) 𝑥 ) ) ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) )
79 an21 ( ( ( 𝑈 ∈ Grp ∧ ∀ 𝑥 ∈ ( Base ‘ 𝑈 ) ∀ 𝑦 ∈ ( Base ‘ 𝑈 ) ( 𝑥 ( +g𝑈 ) 𝑦 ) = ( 𝑦 ( +g𝑈 ) 𝑥 ) ) ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ↔ ( ∀ 𝑥 ∈ ( Base ‘ 𝑈 ) ∀ 𝑦 ∈ ( Base ‘ 𝑈 ) ( 𝑥 ( +g𝑈 ) 𝑦 ) = ( 𝑦 ( +g𝑈 ) 𝑥 ) ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) )
80 78 79 bitri ( ( 𝑈 ∈ Abel ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ↔ ( ∀ 𝑥 ∈ ( Base ‘ 𝑈 ) ∀ 𝑦 ∈ ( Base ‘ 𝑈 ) ( 𝑥 ( +g𝑈 ) 𝑦 ) = ( 𝑦 ( +g𝑈 ) 𝑥 ) ∧ ( 𝑈 ∈ Grp ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) ) )
81 75 80 sylibr ( 𝜑 → ( 𝑈 ∈ Abel ∧ ( 𝐹0 ) = ( 0g𝑈 ) ) )