Step | Hyp | Ref
| Expression |
1 | | grpkerinj.2 |
. . . . . . . . 9
⊢ 𝑊 = (GId‘𝐺) |
2 | | grpkerinj.4 |
. . . . . . . . 9
⊢ 𝑈 = (GId‘𝐻) |
3 | 1, 2 | ghomidOLD 32858 |
. . . . . . . 8
⊢ ((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) → (𝐹‘𝑊) = 𝑈) |
4 | 3 | sneqd 4137 |
. . . . . . 7
⊢ ((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) → {(𝐹‘𝑊)} = {𝑈}) |
5 | | grpkerinj.1 |
. . . . . . . . . 10
⊢ 𝑋 = ran 𝐺 |
6 | | grpkerinj.3 |
. . . . . . . . . 10
⊢ 𝑌 = ran 𝐻 |
7 | 5, 6 | ghomf 32859 |
. . . . . . . . 9
⊢ ((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) → 𝐹:𝑋⟶𝑌) |
8 | | ffn 5958 |
. . . . . . . . 9
⊢ (𝐹:𝑋⟶𝑌 → 𝐹 Fn 𝑋) |
9 | 7, 8 | syl 17 |
. . . . . . . 8
⊢ ((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) → 𝐹 Fn 𝑋) |
10 | 5, 1 | grpoidcl 26752 |
. . . . . . . . 9
⊢ (𝐺 ∈ GrpOp → 𝑊 ∈ 𝑋) |
11 | 10 | 3ad2ant1 1075 |
. . . . . . . 8
⊢ ((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) → 𝑊 ∈ 𝑋) |
12 | | fnsnfv 6168 |
. . . . . . . 8
⊢ ((𝐹 Fn 𝑋 ∧ 𝑊 ∈ 𝑋) → {(𝐹‘𝑊)} = (𝐹 “ {𝑊})) |
13 | 9, 11, 12 | syl2anc 691 |
. . . . . . 7
⊢ ((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) → {(𝐹‘𝑊)} = (𝐹 “ {𝑊})) |
14 | 4, 13 | eqtr3d 2646 |
. . . . . 6
⊢ ((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) → {𝑈} = (𝐹 “ {𝑊})) |
15 | 14 | imaeq2d 5385 |
. . . . 5
⊢ ((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) → (◡𝐹 “ {𝑈}) = (◡𝐹 “ (𝐹 “ {𝑊}))) |
16 | 15 | adantl 481 |
. . . 4
⊢ ((𝐹:𝑋–1-1→𝑌 ∧ (𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻))) → (◡𝐹 “ {𝑈}) = (◡𝐹 “ (𝐹 “ {𝑊}))) |
17 | 10 | snssd 4281 |
. . . . . 6
⊢ (𝐺 ∈ GrpOp → {𝑊} ⊆ 𝑋) |
18 | 17 | 3ad2ant1 1075 |
. . . . 5
⊢ ((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) → {𝑊} ⊆ 𝑋) |
19 | | f1imacnv 6066 |
. . . . 5
⊢ ((𝐹:𝑋–1-1→𝑌 ∧ {𝑊} ⊆ 𝑋) → (◡𝐹 “ (𝐹 “ {𝑊})) = {𝑊}) |
20 | 18, 19 | sylan2 490 |
. . . 4
⊢ ((𝐹:𝑋–1-1→𝑌 ∧ (𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻))) → (◡𝐹 “ (𝐹 “ {𝑊})) = {𝑊}) |
21 | 16, 20 | eqtrd 2644 |
. . 3
⊢ ((𝐹:𝑋–1-1→𝑌 ∧ (𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻))) → (◡𝐹 “ {𝑈}) = {𝑊}) |
22 | 21 | expcom 450 |
. 2
⊢ ((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) → (𝐹:𝑋–1-1→𝑌 → (◡𝐹 “ {𝑈}) = {𝑊})) |
23 | 7 | adantr 480 |
. . . 4
⊢ (((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) ∧ (◡𝐹 “ {𝑈}) = {𝑊}) → 𝐹:𝑋⟶𝑌) |
24 | | simpl2 1058 |
. . . . . . . 8
⊢ (((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → 𝐻 ∈ GrpOp) |
25 | 7 | ffvelrnda 6267 |
. . . . . . . . 9
⊢ (((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) ∧ 𝑥 ∈ 𝑋) → (𝐹‘𝑥) ∈ 𝑌) |
26 | 25 | adantrr 749 |
. . . . . . . 8
⊢ (((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → (𝐹‘𝑥) ∈ 𝑌) |
27 | 7 | ffvelrnda 6267 |
. . . . . . . . 9
⊢ (((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) ∧ 𝑦 ∈ 𝑋) → (𝐹‘𝑦) ∈ 𝑌) |
28 | 27 | adantrl 748 |
. . . . . . . 8
⊢ (((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → (𝐹‘𝑦) ∈ 𝑌) |
29 | | eqid 2610 |
. . . . . . . . 9
⊢ (
/𝑔 ‘𝐻) = ( /𝑔 ‘𝐻) |
30 | 6, 2, 29 | grpoeqdivid 32850 |
. . . . . . . 8
⊢ ((𝐻 ∈ GrpOp ∧ (𝐹‘𝑥) ∈ 𝑌 ∧ (𝐹‘𝑦) ∈ 𝑌) → ((𝐹‘𝑥) = (𝐹‘𝑦) ↔ ((𝐹‘𝑥)( /𝑔 ‘𝐻)(𝐹‘𝑦)) = 𝑈)) |
31 | 24, 26, 28, 30 | syl3anc 1318 |
. . . . . . 7
⊢ (((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → ((𝐹‘𝑥) = (𝐹‘𝑦) ↔ ((𝐹‘𝑥)( /𝑔 ‘𝐻)(𝐹‘𝑦)) = 𝑈)) |
32 | 31 | adantlr 747 |
. . . . . 6
⊢ ((((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) ∧ (◡𝐹 “ {𝑈}) = {𝑊}) ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → ((𝐹‘𝑥) = (𝐹‘𝑦) ↔ ((𝐹‘𝑥)( /𝑔 ‘𝐻)(𝐹‘𝑦)) = 𝑈)) |
33 | | eqid 2610 |
. . . . . . . . . 10
⊢ (
/𝑔 ‘𝐺) = ( /𝑔 ‘𝐺) |
34 | 5, 33, 29 | ghomdiv 32861 |
. . . . . . . . 9
⊢ (((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → (𝐹‘(𝑥( /𝑔 ‘𝐺)𝑦)) = ((𝐹‘𝑥)( /𝑔 ‘𝐻)(𝐹‘𝑦))) |
35 | 34 | adantlr 747 |
. . . . . . . 8
⊢ ((((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) ∧ (◡𝐹 “ {𝑈}) = {𝑊}) ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → (𝐹‘(𝑥( /𝑔 ‘𝐺)𝑦)) = ((𝐹‘𝑥)( /𝑔 ‘𝐻)(𝐹‘𝑦))) |
36 | 35 | eqeq1d 2612 |
. . . . . . 7
⊢ ((((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) ∧ (◡𝐹 “ {𝑈}) = {𝑊}) ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → ((𝐹‘(𝑥( /𝑔 ‘𝐺)𝑦)) = 𝑈 ↔ ((𝐹‘𝑥)( /𝑔 ‘𝐻)(𝐹‘𝑦)) = 𝑈)) |
37 | | fvex 6113 |
. . . . . . . . . . 11
⊢
(GId‘𝐻) ∈
V |
38 | 2, 37 | eqeltri 2684 |
. . . . . . . . . 10
⊢ 𝑈 ∈ V |
39 | 38 | snid 4155 |
. . . . . . . . 9
⊢ 𝑈 ∈ {𝑈} |
40 | | eleq1 2676 |
. . . . . . . . 9
⊢ ((𝐹‘(𝑥( /𝑔 ‘𝐺)𝑦)) = 𝑈 → ((𝐹‘(𝑥( /𝑔 ‘𝐺)𝑦)) ∈ {𝑈} ↔ 𝑈 ∈ {𝑈})) |
41 | 39, 40 | mpbiri 247 |
. . . . . . . 8
⊢ ((𝐹‘(𝑥( /𝑔 ‘𝐺)𝑦)) = 𝑈 → (𝐹‘(𝑥( /𝑔 ‘𝐺)𝑦)) ∈ {𝑈}) |
42 | | ffun 5961 |
. . . . . . . . . . . . . 14
⊢ (𝐹:𝑋⟶𝑌 → Fun 𝐹) |
43 | 7, 42 | syl 17 |
. . . . . . . . . . . . 13
⊢ ((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) → Fun 𝐹) |
44 | 43 | adantr 480 |
. . . . . . . . . . . 12
⊢ (((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → Fun 𝐹) |
45 | 5, 33 | grpodivcl 26777 |
. . . . . . . . . . . . . . 15
⊢ ((𝐺 ∈ GrpOp ∧ 𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋) → (𝑥( /𝑔 ‘𝐺)𝑦) ∈ 𝑋) |
46 | 45 | 3expb 1258 |
. . . . . . . . . . . . . 14
⊢ ((𝐺 ∈ GrpOp ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → (𝑥( /𝑔 ‘𝐺)𝑦) ∈ 𝑋) |
47 | 46 | 3ad2antl1 1216 |
. . . . . . . . . . . . 13
⊢ (((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → (𝑥( /𝑔 ‘𝐺)𝑦) ∈ 𝑋) |
48 | | fdm 5964 |
. . . . . . . . . . . . . . 15
⊢ (𝐹:𝑋⟶𝑌 → dom 𝐹 = 𝑋) |
49 | 7, 48 | syl 17 |
. . . . . . . . . . . . . 14
⊢ ((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) → dom 𝐹 = 𝑋) |
50 | 49 | adantr 480 |
. . . . . . . . . . . . 13
⊢ (((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → dom 𝐹 = 𝑋) |
51 | 47, 50 | eleqtrrd 2691 |
. . . . . . . . . . . 12
⊢ (((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → (𝑥( /𝑔 ‘𝐺)𝑦) ∈ dom 𝐹) |
52 | | fvimacnv 6240 |
. . . . . . . . . . . 12
⊢ ((Fun
𝐹 ∧ (𝑥( /𝑔 ‘𝐺)𝑦) ∈ dom 𝐹) → ((𝐹‘(𝑥( /𝑔 ‘𝐺)𝑦)) ∈ {𝑈} ↔ (𝑥( /𝑔 ‘𝐺)𝑦) ∈ (◡𝐹 “ {𝑈}))) |
53 | 44, 51, 52 | syl2anc 691 |
. . . . . . . . . . 11
⊢ (((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → ((𝐹‘(𝑥( /𝑔 ‘𝐺)𝑦)) ∈ {𝑈} ↔ (𝑥( /𝑔 ‘𝐺)𝑦) ∈ (◡𝐹 “ {𝑈}))) |
54 | | eleq2 2677 |
. . . . . . . . . . 11
⊢ ((◡𝐹 “ {𝑈}) = {𝑊} → ((𝑥( /𝑔 ‘𝐺)𝑦) ∈ (◡𝐹 “ {𝑈}) ↔ (𝑥( /𝑔 ‘𝐺)𝑦) ∈ {𝑊})) |
55 | 53, 54 | sylan9bb 732 |
. . . . . . . . . 10
⊢ ((((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) ∧ (◡𝐹 “ {𝑈}) = {𝑊}) → ((𝐹‘(𝑥( /𝑔 ‘𝐺)𝑦)) ∈ {𝑈} ↔ (𝑥( /𝑔 ‘𝐺)𝑦) ∈ {𝑊})) |
56 | 55 | an32s 842 |
. . . . . . . . 9
⊢ ((((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) ∧ (◡𝐹 “ {𝑈}) = {𝑊}) ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → ((𝐹‘(𝑥( /𝑔 ‘𝐺)𝑦)) ∈ {𝑈} ↔ (𝑥( /𝑔 ‘𝐺)𝑦) ∈ {𝑊})) |
57 | | elsni 4142 |
. . . . . . . . . . 11
⊢ ((𝑥( /𝑔
‘𝐺)𝑦) ∈ {𝑊} → (𝑥( /𝑔 ‘𝐺)𝑦) = 𝑊) |
58 | 5, 1, 33 | grpoeqdivid 32850 |
. . . . . . . . . . . . . 14
⊢ ((𝐺 ∈ GrpOp ∧ 𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋) → (𝑥 = 𝑦 ↔ (𝑥( /𝑔 ‘𝐺)𝑦) = 𝑊)) |
59 | 58 | biimprd 237 |
. . . . . . . . . . . . 13
⊢ ((𝐺 ∈ GrpOp ∧ 𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋) → ((𝑥( /𝑔 ‘𝐺)𝑦) = 𝑊 → 𝑥 = 𝑦)) |
60 | 59 | 3expb 1258 |
. . . . . . . . . . . 12
⊢ ((𝐺 ∈ GrpOp ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → ((𝑥( /𝑔 ‘𝐺)𝑦) = 𝑊 → 𝑥 = 𝑦)) |
61 | 60 | 3ad2antl1 1216 |
. . . . . . . . . . 11
⊢ (((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → ((𝑥( /𝑔 ‘𝐺)𝑦) = 𝑊 → 𝑥 = 𝑦)) |
62 | 57, 61 | syl5 33 |
. . . . . . . . . 10
⊢ (((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → ((𝑥( /𝑔 ‘𝐺)𝑦) ∈ {𝑊} → 𝑥 = 𝑦)) |
63 | 62 | adantlr 747 |
. . . . . . . . 9
⊢ ((((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) ∧ (◡𝐹 “ {𝑈}) = {𝑊}) ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → ((𝑥( /𝑔 ‘𝐺)𝑦) ∈ {𝑊} → 𝑥 = 𝑦)) |
64 | 56, 63 | sylbid 229 |
. . . . . . . 8
⊢ ((((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) ∧ (◡𝐹 “ {𝑈}) = {𝑊}) ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → ((𝐹‘(𝑥( /𝑔 ‘𝐺)𝑦)) ∈ {𝑈} → 𝑥 = 𝑦)) |
65 | 41, 64 | syl5 33 |
. . . . . . 7
⊢ ((((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) ∧ (◡𝐹 “ {𝑈}) = {𝑊}) ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → ((𝐹‘(𝑥( /𝑔 ‘𝐺)𝑦)) = 𝑈 → 𝑥 = 𝑦)) |
66 | 36, 65 | sylbird 249 |
. . . . . 6
⊢ ((((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) ∧ (◡𝐹 “ {𝑈}) = {𝑊}) ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → (((𝐹‘𝑥)( /𝑔 ‘𝐻)(𝐹‘𝑦)) = 𝑈 → 𝑥 = 𝑦)) |
67 | 32, 66 | sylbid 229 |
. . . . 5
⊢ ((((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) ∧ (◡𝐹 “ {𝑈}) = {𝑊}) ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → ((𝐹‘𝑥) = (𝐹‘𝑦) → 𝑥 = 𝑦)) |
68 | 67 | ralrimivva 2954 |
. . . 4
⊢ (((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) ∧ (◡𝐹 “ {𝑈}) = {𝑊}) → ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 ((𝐹‘𝑥) = (𝐹‘𝑦) → 𝑥 = 𝑦)) |
69 | | dff13 6416 |
. . . 4
⊢ (𝐹:𝑋–1-1→𝑌 ↔ (𝐹:𝑋⟶𝑌 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 ((𝐹‘𝑥) = (𝐹‘𝑦) → 𝑥 = 𝑦))) |
70 | 23, 68, 69 | sylanbrc 695 |
. . 3
⊢ (((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) ∧ (◡𝐹 “ {𝑈}) = {𝑊}) → 𝐹:𝑋–1-1→𝑌) |
71 | 70 | ex 449 |
. 2
⊢ ((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) → ((◡𝐹 “ {𝑈}) = {𝑊} → 𝐹:𝑋–1-1→𝑌)) |
72 | 22, 71 | impbid 201 |
1
⊢ ((𝐺 ∈ GrpOp ∧ 𝐻 ∈ GrpOp ∧ 𝐹 ∈ (𝐺 GrpOpHom 𝐻)) → (𝐹:𝑋–1-1→𝑌 ↔ (◡𝐹 “ {𝑈}) = {𝑊})) |