Theorem ghmf1 13923

Description: Two ways of saying a group homomorphism is 1-1 into its codomain. (Contributed by Paul Chapman, 3-Mar-2008.) (Revised by Mario Carneiro, 13-Jan-2015.) (Proof shortened by AV, 4-Apr-2025.)

Hypotheses

Ref	Expression
f1ghm0to0.a	⊢ 𝐴 = (Base‘𝑅)
f1ghm0to0.b	⊢ 𝐵 = (Base‘𝑆)
f1ghm0to0.n	⊢ 𝑁 = (0g‘𝑅)
f1ghm0to0.0	⊢ 0 = (0g‘𝑆)

Assertion

Ref	Expression
ghmf1	⊢ (𝐹 ∈ (𝑅 GrpHom 𝑆) → (𝐹:𝐴–1-1→𝐵 ↔ ∀𝑥 ∈ 𝐴 ((𝐹‘𝑥) = 0 → 𝑥 = 𝑁)))

Distinct variable groups:   𝑥, 0   𝑥,𝐴   𝑥,𝐵   𝑥,𝐹   𝑥,𝑁   𝑥,𝑅   𝑥,𝑆

Proof of Theorem ghmf1

Dummy variables 𝑦 𝑧 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		f1ghm0to0.a	. . . . . 6 ⊢ 𝐴 = (Base‘𝑅)
2		f1ghm0to0.b	. . . . . 6 ⊢ 𝐵 = (Base‘𝑆)
3		f1ghm0to0.n	. . . . . 6 ⊢ 𝑁 = (0g‘𝑅)
4		f1ghm0to0.0	. . . . . 6 ⊢ 0 = (0g‘𝑆)
5	1, 2, 3, 4	f1ghm0to0 13922	. . . . 5 ⊢ ((𝐹 ∈ (𝑅 GrpHom 𝑆) ∧ 𝐹:𝐴–1-1→𝐵 ∧ 𝑥 ∈ 𝐴) → ((𝐹‘𝑥) = 0 ↔ 𝑥 = 𝑁))
6	5	3expa 1230	. . . 4 ⊢ (((𝐹 ∈ (𝑅 GrpHom 𝑆) ∧ 𝐹:𝐴–1-1→𝐵) ∧ 𝑥 ∈ 𝐴) → ((𝐹‘𝑥) = 0 ↔ 𝑥 = 𝑁))
7	6	biimpd 144	. . 3 ⊢ (((𝐹 ∈ (𝑅 GrpHom 𝑆) ∧ 𝐹:𝐴–1-1→𝐵) ∧ 𝑥 ∈ 𝐴) → ((𝐹‘𝑥) = 0 → 𝑥 = 𝑁))
8	7	ralrimiva 2606	. 2 ⊢ ((𝐹 ∈ (𝑅 GrpHom 𝑆) ∧ 𝐹:𝐴–1-1→𝐵) → ∀𝑥 ∈ 𝐴 ((𝐹‘𝑥) = 0 → 𝑥 = 𝑁))
9	1, 2	ghmf 13897	. . . 4 ⊢ (𝐹 ∈ (𝑅 GrpHom 𝑆) → 𝐹:𝐴⟶𝐵)
10	9	adantr 276	. . 3 ⊢ ((𝐹 ∈ (𝑅 GrpHom 𝑆) ∧ ∀𝑥 ∈ 𝐴 ((𝐹‘𝑥) = 0 → 𝑥 = 𝑁)) → 𝐹:𝐴⟶𝐵)
11		eqid 2231	. . . . . . . . . 10 ⊢ (-g‘𝑅) = (-g‘𝑅)
12		eqid 2231	. . . . . . . . . 10 ⊢ (-g‘𝑆) = (-g‘𝑆)
13	1, 11, 12	ghmsub 13901	. . . . . . . . 9 ⊢ ((𝐹 ∈ (𝑅 GrpHom 𝑆) ∧ 𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴) → (𝐹‘(𝑦(-g‘𝑅)𝑧)) = ((𝐹‘𝑦)(-g‘𝑆)(𝐹‘𝑧)))
14	13	3expb 1231	. . . . . . . 8 ⊢ ((𝐹 ∈ (𝑅 GrpHom 𝑆) ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) → (𝐹‘(𝑦(-g‘𝑅)𝑧)) = ((𝐹‘𝑦)(-g‘𝑆)(𝐹‘𝑧)))
15	14	adantlr 477	. . . . . . 7 ⊢ (((𝐹 ∈ (𝑅 GrpHom 𝑆) ∧ ∀𝑥 ∈ 𝐴 ((𝐹‘𝑥) = 0 → 𝑥 = 𝑁)) ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) → (𝐹‘(𝑦(-g‘𝑅)𝑧)) = ((𝐹‘𝑦)(-g‘𝑆)(𝐹‘𝑧)))
16	15	eqeq1d 2240	. . . . . 6 ⊢ (((𝐹 ∈ (𝑅 GrpHom 𝑆) ∧ ∀𝑥 ∈ 𝐴 ((𝐹‘𝑥) = 0 → 𝑥 = 𝑁)) ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) → ((𝐹‘(𝑦(-g‘𝑅)𝑧)) = 0 ↔ ((𝐹‘𝑦)(-g‘𝑆)(𝐹‘𝑧)) = 0 ))
17		fveqeq2 5657	. . . . . . . 8 ⊢ (𝑥 = (𝑦(-g‘𝑅)𝑧) → ((𝐹‘𝑥) = 0 ↔ (𝐹‘(𝑦(-g‘𝑅)𝑧)) = 0 ))
18		eqeq1 2238	. . . . . . . 8 ⊢ (𝑥 = (𝑦(-g‘𝑅)𝑧) → (𝑥 = 𝑁 ↔ (𝑦(-g‘𝑅)𝑧) = 𝑁))
19	17, 18	imbi12d 234	. . . . . . 7 ⊢ (𝑥 = (𝑦(-g‘𝑅)𝑧) → (((𝐹‘𝑥) = 0 → 𝑥 = 𝑁) ↔ ((𝐹‘(𝑦(-g‘𝑅)𝑧)) = 0 → (𝑦(-g‘𝑅)𝑧) = 𝑁)))
20		simplr 529	. . . . . . 7 ⊢ (((𝐹 ∈ (𝑅 GrpHom 𝑆) ∧ ∀𝑥 ∈ 𝐴 ((𝐹‘𝑥) = 0 → 𝑥 = 𝑁)) ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) → ∀𝑥 ∈ 𝐴 ((𝐹‘𝑥) = 0 → 𝑥 = 𝑁))
21		ghmgrp1 13895	. . . . . . . . 9 ⊢ (𝐹 ∈ (𝑅 GrpHom 𝑆) → 𝑅 ∈ Grp)
22	21	adantr 276	. . . . . . . 8 ⊢ ((𝐹 ∈ (𝑅 GrpHom 𝑆) ∧ ∀𝑥 ∈ 𝐴 ((𝐹‘𝑥) = 0 → 𝑥 = 𝑁)) → 𝑅 ∈ Grp)
23	1, 11	grpsubcl 13726	. . . . . . . . 9 ⊢ ((𝑅 ∈ Grp ∧ 𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴) → (𝑦(-g‘𝑅)𝑧) ∈ 𝐴)
24	23	3expb 1231	. . . . . . . 8 ⊢ ((𝑅 ∈ Grp ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) → (𝑦(-g‘𝑅)𝑧) ∈ 𝐴)
25	22, 24	sylan 283	. . . . . . 7 ⊢ (((𝐹 ∈ (𝑅 GrpHom 𝑆) ∧ ∀𝑥 ∈ 𝐴 ((𝐹‘𝑥) = 0 → 𝑥 = 𝑁)) ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) → (𝑦(-g‘𝑅)𝑧) ∈ 𝐴)
26	19, 20, 25	rspcdva 2916	. . . . . 6 ⊢ (((𝐹 ∈ (𝑅 GrpHom 𝑆) ∧ ∀𝑥 ∈ 𝐴 ((𝐹‘𝑥) = 0 → 𝑥 = 𝑁)) ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) → ((𝐹‘(𝑦(-g‘𝑅)𝑧)) = 0 → (𝑦(-g‘𝑅)𝑧) = 𝑁))
27	16, 26	sylbird 170	. . . . 5 ⊢ (((𝐹 ∈ (𝑅 GrpHom 𝑆) ∧ ∀𝑥 ∈ 𝐴 ((𝐹‘𝑥) = 0 → 𝑥 = 𝑁)) ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) → (((𝐹‘𝑦)(-g‘𝑆)(𝐹‘𝑧)) = 0 → (𝑦(-g‘𝑅)𝑧) = 𝑁))
28		ghmgrp2 13896	. . . . . . 7 ⊢ (𝐹 ∈ (𝑅 GrpHom 𝑆) → 𝑆 ∈ Grp)
29	28	ad2antrr 488	. . . . . 6 ⊢ (((𝐹 ∈ (𝑅 GrpHom 𝑆) ∧ ∀𝑥 ∈ 𝐴 ((𝐹‘𝑥) = 0 → 𝑥 = 𝑁)) ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) → 𝑆 ∈ Grp)
30	9	ad2antrr 488	. . . . . . 7 ⊢ (((𝐹 ∈ (𝑅 GrpHom 𝑆) ∧ ∀𝑥 ∈ 𝐴 ((𝐹‘𝑥) = 0 → 𝑥 = 𝑁)) ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) → 𝐹:𝐴⟶𝐵)
31		simprl 531	. . . . . . 7 ⊢ (((𝐹 ∈ (𝑅 GrpHom 𝑆) ∧ ∀𝑥 ∈ 𝐴 ((𝐹‘𝑥) = 0 → 𝑥 = 𝑁)) ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) → 𝑦 ∈ 𝐴)
32	30, 31	ffvelcdmd 5791	. . . . . 6 ⊢ (((𝐹 ∈ (𝑅 GrpHom 𝑆) ∧ ∀𝑥 ∈ 𝐴 ((𝐹‘𝑥) = 0 → 𝑥 = 𝑁)) ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) → (𝐹‘𝑦) ∈ 𝐵)
33		simprr 533	. . . . . . 7 ⊢ (((𝐹 ∈ (𝑅 GrpHom 𝑆) ∧ ∀𝑥 ∈ 𝐴 ((𝐹‘𝑥) = 0 → 𝑥 = 𝑁)) ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) → 𝑧 ∈ 𝐴)
34	30, 33	ffvelcdmd 5791	. . . . . 6 ⊢ (((𝐹 ∈ (𝑅 GrpHom 𝑆) ∧ ∀𝑥 ∈ 𝐴 ((𝐹‘𝑥) = 0 → 𝑥 = 𝑁)) ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) → (𝐹‘𝑧) ∈ 𝐵)
35	2, 4, 12	grpsubeq0 13732	. . . . . 6 ⊢ ((𝑆 ∈ Grp ∧ (𝐹‘𝑦) ∈ 𝐵 ∧ (𝐹‘𝑧) ∈ 𝐵) → (((𝐹‘𝑦)(-g‘𝑆)(𝐹‘𝑧)) = 0 ↔ (𝐹‘𝑦) = (𝐹‘𝑧)))
36	29, 32, 34, 35	syl3anc 1274	. . . . 5 ⊢ (((𝐹 ∈ (𝑅 GrpHom 𝑆) ∧ ∀𝑥 ∈ 𝐴 ((𝐹‘𝑥) = 0 → 𝑥 = 𝑁)) ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) → (((𝐹‘𝑦)(-g‘𝑆)(𝐹‘𝑧)) = 0 ↔ (𝐹‘𝑦) = (𝐹‘𝑧)))
37	21	ad2antrr 488	. . . . . 6 ⊢ (((𝐹 ∈ (𝑅 GrpHom 𝑆) ∧ ∀𝑥 ∈ 𝐴 ((𝐹‘𝑥) = 0 → 𝑥 = 𝑁)) ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) → 𝑅 ∈ Grp)
38	1, 3, 11	grpsubeq0 13732	. . . . . 6 ⊢ ((𝑅 ∈ Grp ∧ 𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴) → ((𝑦(-g‘𝑅)𝑧) = 𝑁 ↔ 𝑦 = 𝑧))
39	37, 31, 33, 38	syl3anc 1274	. . . . 5 ⊢ (((𝐹 ∈ (𝑅 GrpHom 𝑆) ∧ ∀𝑥 ∈ 𝐴 ((𝐹‘𝑥) = 0 → 𝑥 = 𝑁)) ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) → ((𝑦(-g‘𝑅)𝑧) = 𝑁 ↔ 𝑦 = 𝑧))
40	27, 36, 39	3imtr3d 202	. . . 4 ⊢ (((𝐹 ∈ (𝑅 GrpHom 𝑆) ∧ ∀𝑥 ∈ 𝐴 ((𝐹‘𝑥) = 0 → 𝑥 = 𝑁)) ∧ (𝑦 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) → ((𝐹‘𝑦) = (𝐹‘𝑧) → 𝑦 = 𝑧))
41	40	ralrimivva 2615	. . 3 ⊢ ((𝐹 ∈ (𝑅 GrpHom 𝑆) ∧ ∀𝑥 ∈ 𝐴 ((𝐹‘𝑥) = 0 → 𝑥 = 𝑁)) → ∀𝑦 ∈ 𝐴 ∀𝑧 ∈ 𝐴 ((𝐹‘𝑦) = (𝐹‘𝑧) → 𝑦 = 𝑧))
42		dff13 5919	. . 3 ⊢ (𝐹:𝐴–1-1→𝐵 ↔ (𝐹:𝐴⟶𝐵 ∧ ∀𝑦 ∈ 𝐴 ∀𝑧 ∈ 𝐴 ((𝐹‘𝑦) = (𝐹‘𝑧) → 𝑦 = 𝑧)))
43	10, 41, 42	sylanbrc 417	. 2 ⊢ ((𝐹 ∈ (𝑅 GrpHom 𝑆) ∧ ∀𝑥 ∈ 𝐴 ((𝐹‘𝑥) = 0 → 𝑥 = 𝑁)) → 𝐹:𝐴–1-1→𝐵)
44	8, 43	impbida 600	1 ⊢ (𝐹 ∈ (𝑅 GrpHom 𝑆) → (𝐹:𝐴–1-1→𝐵 ↔ ∀𝑥 ∈ 𝐴 ((𝐹‘𝑥) = 0 → 𝑥 = 𝑁)))

Syntax hints:   → wi 4   ∧ wa 104   ↔ wb 105   = wceq 1398   ∈ wcel 2202  ∀wral 2511  ⟶wf 5329  –1-1→wf1 5330  ‘cfv 5333  (class class class)co 6028  Basecbs 13145  0_gc0g 13402  Grpcgrp 13646  -_gcsg 13648   GrpHom cghm 13890

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 619  ax-in2 620  ax-io 717  ax-5 1496  ax-7 1497  ax-gen 1498  ax-ie1 1542  ax-ie2 1543  ax-8 1553  ax-10 1554  ax-11 1555  ax-i12 1556  ax-bndl 1558  ax-4 1559  ax-17 1575  ax-i9 1579  ax-ial 1583  ax-i5r 1584  ax-13 2204  ax-14 2205  ax-ext 2213  ax-coll 4209  ax-sep 4212  ax-pow 4270  ax-pr 4305  ax-un 4536  ax-setind 4641  ax-cnex 8166  ax-resscn 8167  ax-1re 8169  ax-addrcl 8172

This theorem depends on definitions:  df-bi 117  df-3an 1007  df-tru 1401  df-fal 1404  df-nf 1510  df-sb 1811  df-eu 2082  df-mo 2083  df-clab 2218  df-cleq 2224  df-clel 2227  df-nfc 2364  df-ne 2404  df-ral 2516  df-rex 2517  df-reu 2518  df-rmo 2519  df-rab 2520  df-v 2805  df-sbc 3033  df-csb 3129  df-dif 3203  df-un 3205  df-in 3207  df-ss 3214  df-pw 3658  df-sn 3679  df-pr 3680  df-op 3682  df-uni 3899  df-int 3934  df-iun 3977  df-br 4094  df-opab 4156  df-mpt 4157  df-id 4396  df-xp 4737  df-rel 4738  df-cnv 4739  df-co 4740  df-dm 4741  df-rn 4742  df-res 4743  df-ima 4744  df-iota 5293  df-fun 5335  df-fn 5336  df-f 5337  df-f1 5338  df-fo 5339  df-f1o 5340  df-fv 5341  df-riota 5981  df-ov 6031  df-oprab 6032  df-mpo 6033  df-1st 6312  df-2nd 6313  df-inn 9186  df-2 9244  df-ndx 13148  df-slot 13149  df-base 13151  df-plusg 13236  df-0g 13404  df-mgm 13502  df-sgrp 13548  df-mnd 13563  df-grp 13649  df-minusg 13650  df-sbg 13651  df-ghm 13891

This theorem is referenced by: (None)