| Step | Hyp | Ref
 | Expression | 
| 1 |   | grplmulf1o.n | 
. 2
⊢ 𝐹 = (𝑥 ∈ 𝐵 ↦ (𝑋 + 𝑥)) | 
| 2 |   | grplmulf1o.b | 
. . . 4
⊢ 𝐵 = (Base‘𝐺) | 
| 3 |   | grplmulf1o.p | 
. . . 4
⊢  + =
(+g‘𝐺) | 
| 4 | 2, 3 | grpcl 13140 | 
. . 3
⊢ ((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵 ∧ 𝑥 ∈ 𝐵) → (𝑋 + 𝑥) ∈ 𝐵) | 
| 5 | 4 | 3expa 1205 | 
. 2
⊢ (((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) ∧ 𝑥 ∈ 𝐵) → (𝑋 + 𝑥) ∈ 𝐵) | 
| 6 |   | eqid 2196 | 
. . . 4
⊢
(invg‘𝐺) = (invg‘𝐺) | 
| 7 | 2, 6 | grpinvcl 13180 | 
. . 3
⊢ ((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) → ((invg‘𝐺)‘𝑋) ∈ 𝐵) | 
| 8 | 2, 3 | grpcl 13140 | 
. . . 4
⊢ ((𝐺 ∈ Grp ∧
((invg‘𝐺)‘𝑋) ∈ 𝐵 ∧ 𝑦 ∈ 𝐵) → (((invg‘𝐺)‘𝑋) + 𝑦) ∈ 𝐵) | 
| 9 | 8 | 3expa 1205 | 
. . 3
⊢ (((𝐺 ∈ Grp ∧
((invg‘𝐺)‘𝑋) ∈ 𝐵) ∧ 𝑦 ∈ 𝐵) → (((invg‘𝐺)‘𝑋) + 𝑦) ∈ 𝐵) | 
| 10 | 7, 9 | syldanl 449 | 
. 2
⊢ (((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) ∧ 𝑦 ∈ 𝐵) → (((invg‘𝐺)‘𝑋) + 𝑦) ∈ 𝐵) | 
| 11 |   | eqcom 2198 | 
. . 3
⊢ (𝑥 =
(((invg‘𝐺)‘𝑋) + 𝑦) ↔ (((invg‘𝐺)‘𝑋) + 𝑦) = 𝑥) | 
| 12 |   | simpll 527 | 
. . . . 5
⊢ (((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → 𝐺 ∈ Grp) | 
| 13 | 10 | adantrl 478 | 
. . . . 5
⊢ (((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → (((invg‘𝐺)‘𝑋) + 𝑦) ∈ 𝐵) | 
| 14 |   | simprl 529 | 
. . . . 5
⊢ (((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → 𝑥 ∈ 𝐵) | 
| 15 |   | simplr 528 | 
. . . . 5
⊢ (((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → 𝑋 ∈ 𝐵) | 
| 16 | 2, 3 | grplcan 13194 | 
. . . . 5
⊢ ((𝐺 ∈ Grp ∧
((((invg‘𝐺)‘𝑋) + 𝑦) ∈ 𝐵 ∧ 𝑥 ∈ 𝐵 ∧ 𝑋 ∈ 𝐵)) → ((𝑋 +
(((invg‘𝐺)‘𝑋) + 𝑦)) = (𝑋 + 𝑥) ↔ (((invg‘𝐺)‘𝑋) + 𝑦) = 𝑥)) | 
| 17 | 12, 13, 14, 15, 16 | syl13anc 1251 | 
. . . 4
⊢ (((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → ((𝑋 +
(((invg‘𝐺)‘𝑋) + 𝑦)) = (𝑋 + 𝑥) ↔ (((invg‘𝐺)‘𝑋) + 𝑦) = 𝑥)) | 
| 18 |   | eqid 2196 | 
. . . . . . . . 9
⊢
(0g‘𝐺) = (0g‘𝐺) | 
| 19 | 2, 3, 18, 6 | grprinv 13183 | 
. . . . . . . 8
⊢ ((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) → (𝑋 +
((invg‘𝐺)‘𝑋)) = (0g‘𝐺)) | 
| 20 | 19 | adantr 276 | 
. . . . . . 7
⊢ (((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → (𝑋 +
((invg‘𝐺)‘𝑋)) = (0g‘𝐺)) | 
| 21 | 20 | oveq1d 5937 | 
. . . . . 6
⊢ (((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → ((𝑋 +
((invg‘𝐺)‘𝑋)) + 𝑦) = ((0g‘𝐺) + 𝑦)) | 
| 22 | 7 | adantr 276 | 
. . . . . . 7
⊢ (((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → ((invg‘𝐺)‘𝑋) ∈ 𝐵) | 
| 23 |   | simprr 531 | 
. . . . . . 7
⊢ (((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → 𝑦 ∈ 𝐵) | 
| 24 | 2, 3 | grpass 13141 | 
. . . . . . 7
⊢ ((𝐺 ∈ Grp ∧ (𝑋 ∈ 𝐵 ∧ ((invg‘𝐺)‘𝑋) ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → ((𝑋 +
((invg‘𝐺)‘𝑋)) + 𝑦) = (𝑋 +
(((invg‘𝐺)‘𝑋) + 𝑦))) | 
| 25 | 12, 15, 22, 23, 24 | syl13anc 1251 | 
. . . . . 6
⊢ (((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → ((𝑋 +
((invg‘𝐺)‘𝑋)) + 𝑦) = (𝑋 +
(((invg‘𝐺)‘𝑋) + 𝑦))) | 
| 26 | 2, 3, 18 | grplid 13163 | 
. . . . . . 7
⊢ ((𝐺 ∈ Grp ∧ 𝑦 ∈ 𝐵) → ((0g‘𝐺) + 𝑦) = 𝑦) | 
| 27 | 26 | ad2ant2rl 511 | 
. . . . . 6
⊢ (((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → ((0g‘𝐺) + 𝑦) = 𝑦) | 
| 28 | 21, 25, 27 | 3eqtr3d 2237 | 
. . . . 5
⊢ (((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → (𝑋 +
(((invg‘𝐺)‘𝑋) + 𝑦)) = 𝑦) | 
| 29 | 28 | eqeq1d 2205 | 
. . . 4
⊢ (((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → ((𝑋 +
(((invg‘𝐺)‘𝑋) + 𝑦)) = (𝑋 + 𝑥) ↔ 𝑦 = (𝑋 + 𝑥))) | 
| 30 | 17, 29 | bitr3d 190 | 
. . 3
⊢ (((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → ((((invg‘𝐺)‘𝑋) + 𝑦) = 𝑥 ↔ 𝑦 = (𝑋 + 𝑥))) | 
| 31 | 11, 30 | bitrid 192 | 
. 2
⊢ (((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → (𝑥 = (((invg‘𝐺)‘𝑋) + 𝑦) ↔ 𝑦 = (𝑋 + 𝑥))) | 
| 32 | 1, 5, 10, 31 | f1o2d 6128 | 
1
⊢ ((𝐺 ∈ Grp ∧ 𝑋 ∈ 𝐵) → 𝐹:𝐵–1-1-onto→𝐵) |