Theorem sgrp2rid2 17413

Description: A small semigroup (with two elements) with two right identities which are different if 𝐴 ≠ 𝐵. (Contributed by AV, 10-Feb-2020.)

Hypotheses

Ref	Expression
mgm2nsgrp.s	⊢ 𝑆 = {𝐴, 𝐵}
mgm2nsgrp.b	⊢ (Base‘𝑀) = 𝑆
sgrp2nmnd.o	⊢ (+g‘𝑀) = (𝑥 ∈ 𝑆, 𝑦 ∈ 𝑆 ↦ if(𝑥 = 𝐴, 𝐴, 𝐵))
sgrp2nmnd.p	⊢ ⚬ = (+g‘𝑀)

Assertion

Ref	Expression
sgrp2rid2	⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → ∀𝑥 ∈ 𝑆 ∀𝑦 ∈ 𝑆 (𝑦 ⚬ 𝑥) = 𝑦)

Distinct variable groups:   𝑥,𝑆,𝑦   𝑥,𝐴,𝑦   𝑥,𝐵,𝑦   𝑥,𝑀   𝑥,𝑉   𝑥,𝑊   𝑥, ⚬ ,𝑦

Allowed substitution hints:   𝑀(𝑦)   𝑉(𝑦)   𝑊(𝑦)

Proof of Theorem sgrp2rid2

Step	Hyp	Ref	Expression
1		prid1g 4295	. . . 4 ⊢ (𝐴 ∈ 𝑉 → 𝐴 ∈ {𝐴, 𝐵})
2		mgm2nsgrp.s	. . . 4 ⊢ 𝑆 = {𝐴, 𝐵}
3	1, 2	syl6eleqr 2712	. . 3 ⊢ (𝐴 ∈ 𝑉 → 𝐴 ∈ 𝑆)
4		prid2g 4296	. . . 4 ⊢ (𝐵 ∈ 𝑊 → 𝐵 ∈ {𝐴, 𝐵})
5	4, 2	syl6eleqr 2712	. . 3 ⊢ (𝐵 ∈ 𝑊 → 𝐵 ∈ 𝑆)
6		simpl 473	. . . . 5 ⊢ ((𝐴 ∈ 𝑆 ∧ 𝐵 ∈ 𝑆) → 𝐴 ∈ 𝑆)
7		mgm2nsgrp.b	. . . . . 6 ⊢ (Base‘𝑀) = 𝑆
8		sgrp2nmnd.o	. . . . . 6 ⊢ (+g‘𝑀) = (𝑥 ∈ 𝑆, 𝑦 ∈ 𝑆 ↦ if(𝑥 = 𝐴, 𝐴, 𝐵))
9		sgrp2nmnd.p	. . . . . 6 ⊢ ⚬ = (+g‘𝑀)
10	2, 7, 8, 9	sgrp2nmndlem2 17411	. . . . 5 ⊢ ((𝐴 ∈ 𝑆 ∧ 𝐴 ∈ 𝑆) → (𝐴 ⚬ 𝐴) = 𝐴)
11	6, 10	syldan 487	. . . 4 ⊢ ((𝐴 ∈ 𝑆 ∧ 𝐵 ∈ 𝑆) → (𝐴 ⚬ 𝐴) = 𝐴)
12		oveq1 6657	. . . . . . 7 ⊢ (𝐴 = 𝐵 → (𝐴 ⚬ 𝐴) = (𝐵 ⚬ 𝐴))
13		id 22	. . . . . . 7 ⊢ (𝐴 = 𝐵 → 𝐴 = 𝐵)
14	12, 13	eqeq12d 2637	. . . . . 6 ⊢ (𝐴 = 𝐵 → ((𝐴 ⚬ 𝐴) = 𝐴 ↔ (𝐵 ⚬ 𝐴) = 𝐵))
15	11, 14	syl5ib 234	. . . . 5 ⊢ (𝐴 = 𝐵 → ((𝐴 ∈ 𝑆 ∧ 𝐵 ∈ 𝑆) → (𝐵 ⚬ 𝐴) = 𝐵))
16		simprl 794	. . . . . . 7 ⊢ ((¬ 𝐴 = 𝐵 ∧ (𝐴 ∈ 𝑆 ∧ 𝐵 ∈ 𝑆)) → 𝐴 ∈ 𝑆)
17		simprr 796	. . . . . . 7 ⊢ ((¬ 𝐴 = 𝐵 ∧ (𝐴 ∈ 𝑆 ∧ 𝐵 ∈ 𝑆)) → 𝐵 ∈ 𝑆)
18		df-ne 2795	. . . . . . . . 9 ⊢ (𝐴 ≠ 𝐵 ↔ ¬ 𝐴 = 𝐵)
19	18	biimpri 218	. . . . . . . 8 ⊢ (¬ 𝐴 = 𝐵 → 𝐴 ≠ 𝐵)
20	19	adantr 481	. . . . . . 7 ⊢ ((¬ 𝐴 = 𝐵 ∧ (𝐴 ∈ 𝑆 ∧ 𝐵 ∈ 𝑆)) → 𝐴 ≠ 𝐵)
21	2, 7, 8, 9	sgrp2nmndlem3 17412	. . . . . . 7 ⊢ ((𝐴 ∈ 𝑆 ∧ 𝐵 ∈ 𝑆 ∧ 𝐴 ≠ 𝐵) → (𝐵 ⚬ 𝐴) = 𝐵)
22	16, 17, 20, 21	syl3anc 1326	. . . . . 6 ⊢ ((¬ 𝐴 = 𝐵 ∧ (𝐴 ∈ 𝑆 ∧ 𝐵 ∈ 𝑆)) → (𝐵 ⚬ 𝐴) = 𝐵)
23	22	ex 450	. . . . 5 ⊢ (¬ 𝐴 = 𝐵 → ((𝐴 ∈ 𝑆 ∧ 𝐵 ∈ 𝑆) → (𝐵 ⚬ 𝐴) = 𝐵))
24	15, 23	pm2.61i 176	. . . 4 ⊢ ((𝐴 ∈ 𝑆 ∧ 𝐵 ∈ 𝑆) → (𝐵 ⚬ 𝐴) = 𝐵)
25	2, 7, 8, 9	sgrp2nmndlem2 17411	. . . . 5 ⊢ ((𝐴 ∈ 𝑆 ∧ 𝐵 ∈ 𝑆) → (𝐴 ⚬ 𝐵) = 𝐴)
26	13, 13	oveq12d 6668	. . . . . . . 8 ⊢ (𝐴 = 𝐵 → (𝐴 ⚬ 𝐴) = (𝐵 ⚬ 𝐵))
27	26, 13	eqeq12d 2637	. . . . . . 7 ⊢ (𝐴 = 𝐵 → ((𝐴 ⚬ 𝐴) = 𝐴 ↔ (𝐵 ⚬ 𝐵) = 𝐵))
28	11, 27	syl5ib 234	. . . . . 6 ⊢ (𝐴 = 𝐵 → ((𝐴 ∈ 𝑆 ∧ 𝐵 ∈ 𝑆) → (𝐵 ⚬ 𝐵) = 𝐵))
29	2, 7, 8, 9	sgrp2nmndlem3 17412	. . . . . . . 8 ⊢ ((𝐵 ∈ 𝑆 ∧ 𝐵 ∈ 𝑆 ∧ 𝐴 ≠ 𝐵) → (𝐵 ⚬ 𝐵) = 𝐵)
30	17, 17, 20, 29	syl3anc 1326	. . . . . . 7 ⊢ ((¬ 𝐴 = 𝐵 ∧ (𝐴 ∈ 𝑆 ∧ 𝐵 ∈ 𝑆)) → (𝐵 ⚬ 𝐵) = 𝐵)
31	30	ex 450	. . . . . 6 ⊢ (¬ 𝐴 = 𝐵 → ((𝐴 ∈ 𝑆 ∧ 𝐵 ∈ 𝑆) → (𝐵 ⚬ 𝐵) = 𝐵))
32	28, 31	pm2.61i 176	. . . . 5 ⊢ ((𝐴 ∈ 𝑆 ∧ 𝐵 ∈ 𝑆) → (𝐵 ⚬ 𝐵) = 𝐵)
33	25, 32	jca 554	. . . 4 ⊢ ((𝐴 ∈ 𝑆 ∧ 𝐵 ∈ 𝑆) → ((𝐴 ⚬ 𝐵) = 𝐴 ∧ (𝐵 ⚬ 𝐵) = 𝐵))
34	11, 24, 33	jca31 557	. . 3 ⊢ ((𝐴 ∈ 𝑆 ∧ 𝐵 ∈ 𝑆) → (((𝐴 ⚬ 𝐴) = 𝐴 ∧ (𝐵 ⚬ 𝐴) = 𝐵) ∧ ((𝐴 ⚬ 𝐵) = 𝐴 ∧ (𝐵 ⚬ 𝐵) = 𝐵)))
35	3, 5, 34	syl2an 494	. 2 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (((𝐴 ⚬ 𝐴) = 𝐴 ∧ (𝐵 ⚬ 𝐴) = 𝐵) ∧ ((𝐴 ⚬ 𝐵) = 𝐴 ∧ (𝐵 ⚬ 𝐵) = 𝐵)))
36	2	raleqi 3142	. . . . 5 ⊢ (∀𝑦 ∈ 𝑆 (𝑦 ⚬ 𝑥) = 𝑦 ↔ ∀𝑦 ∈ {𝐴, 𝐵} (𝑦 ⚬ 𝑥) = 𝑦)
37		oveq1 6657	. . . . . . 7 ⊢ (𝑦 = 𝐴 → (𝑦 ⚬ 𝑥) = (𝐴 ⚬ 𝑥))
38		id 22	. . . . . . 7 ⊢ (𝑦 = 𝐴 → 𝑦 = 𝐴)
39	37, 38	eqeq12d 2637	. . . . . 6 ⊢ (𝑦 = 𝐴 → ((𝑦 ⚬ 𝑥) = 𝑦 ↔ (𝐴 ⚬ 𝑥) = 𝐴))
40		oveq1 6657	. . . . . . 7 ⊢ (𝑦 = 𝐵 → (𝑦 ⚬ 𝑥) = (𝐵 ⚬ 𝑥))
41		id 22	. . . . . . 7 ⊢ (𝑦 = 𝐵 → 𝑦 = 𝐵)
42	40, 41	eqeq12d 2637	. . . . . 6 ⊢ (𝑦 = 𝐵 → ((𝑦 ⚬ 𝑥) = 𝑦 ↔ (𝐵 ⚬ 𝑥) = 𝐵))
43	39, 42	ralprg 4234	. . . . 5 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (∀𝑦 ∈ {𝐴, 𝐵} (𝑦 ⚬ 𝑥) = 𝑦 ↔ ((𝐴 ⚬ 𝑥) = 𝐴 ∧ (𝐵 ⚬ 𝑥) = 𝐵)))
44	36, 43	syl5bb 272	. . . 4 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (∀𝑦 ∈ 𝑆 (𝑦 ⚬ 𝑥) = 𝑦 ↔ ((𝐴 ⚬ 𝑥) = 𝐴 ∧ (𝐵 ⚬ 𝑥) = 𝐵)))
45	44	ralbidv 2986	. . 3 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (∀𝑥 ∈ 𝑆 ∀𝑦 ∈ 𝑆 (𝑦 ⚬ 𝑥) = 𝑦 ↔ ∀𝑥 ∈ 𝑆 ((𝐴 ⚬ 𝑥) = 𝐴 ∧ (𝐵 ⚬ 𝑥) = 𝐵)))
46	2	raleqi 3142	. . . 4 ⊢ (∀𝑥 ∈ 𝑆 ((𝐴 ⚬ 𝑥) = 𝐴 ∧ (𝐵 ⚬ 𝑥) = 𝐵) ↔ ∀𝑥 ∈ {𝐴, 𝐵} ((𝐴 ⚬ 𝑥) = 𝐴 ∧ (𝐵 ⚬ 𝑥) = 𝐵))
47		oveq2 6658	. . . . . . 7 ⊢ (𝑥 = 𝐴 → (𝐴 ⚬ 𝑥) = (𝐴 ⚬ 𝐴))
48	47	eqeq1d 2624	. . . . . 6 ⊢ (𝑥 = 𝐴 → ((𝐴 ⚬ 𝑥) = 𝐴 ↔ (𝐴 ⚬ 𝐴) = 𝐴))
49		oveq2 6658	. . . . . . 7 ⊢ (𝑥 = 𝐴 → (𝐵 ⚬ 𝑥) = (𝐵 ⚬ 𝐴))
50	49	eqeq1d 2624	. . . . . 6 ⊢ (𝑥 = 𝐴 → ((𝐵 ⚬ 𝑥) = 𝐵 ↔ (𝐵 ⚬ 𝐴) = 𝐵))
51	48, 50	anbi12d 747	. . . . 5 ⊢ (𝑥 = 𝐴 → (((𝐴 ⚬ 𝑥) = 𝐴 ∧ (𝐵 ⚬ 𝑥) = 𝐵) ↔ ((𝐴 ⚬ 𝐴) = 𝐴 ∧ (𝐵 ⚬ 𝐴) = 𝐵)))
52		oveq2 6658	. . . . . . 7 ⊢ (𝑥 = 𝐵 → (𝐴 ⚬ 𝑥) = (𝐴 ⚬ 𝐵))
53	52	eqeq1d 2624	. . . . . 6 ⊢ (𝑥 = 𝐵 → ((𝐴 ⚬ 𝑥) = 𝐴 ↔ (𝐴 ⚬ 𝐵) = 𝐴))
54		oveq2 6658	. . . . . . 7 ⊢ (𝑥 = 𝐵 → (𝐵 ⚬ 𝑥) = (𝐵 ⚬ 𝐵))
55	54	eqeq1d 2624	. . . . . 6 ⊢ (𝑥 = 𝐵 → ((𝐵 ⚬ 𝑥) = 𝐵 ↔ (𝐵 ⚬ 𝐵) = 𝐵))
56	53, 55	anbi12d 747	. . . . 5 ⊢ (𝑥 = 𝐵 → (((𝐴 ⚬ 𝑥) = 𝐴 ∧ (𝐵 ⚬ 𝑥) = 𝐵) ↔ ((𝐴 ⚬ 𝐵) = 𝐴 ∧ (𝐵 ⚬ 𝐵) = 𝐵)))
57	51, 56	ralprg 4234	. . . 4 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (∀𝑥 ∈ {𝐴, 𝐵} ((𝐴 ⚬ 𝑥) = 𝐴 ∧ (𝐵 ⚬ 𝑥) = 𝐵) ↔ (((𝐴 ⚬ 𝐴) = 𝐴 ∧ (𝐵 ⚬ 𝐴) = 𝐵) ∧ ((𝐴 ⚬ 𝐵) = 𝐴 ∧ (𝐵 ⚬ 𝐵) = 𝐵))))
58	46, 57	syl5bb 272	. . 3 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (∀𝑥 ∈ 𝑆 ((𝐴 ⚬ 𝑥) = 𝐴 ∧ (𝐵 ⚬ 𝑥) = 𝐵) ↔ (((𝐴 ⚬ 𝐴) = 𝐴 ∧ (𝐵 ⚬ 𝐴) = 𝐵) ∧ ((𝐴 ⚬ 𝐵) = 𝐴 ∧ (𝐵 ⚬ 𝐵) = 𝐵))))
59	45, 58	bitrd 268	. 2 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (∀𝑥 ∈ 𝑆 ∀𝑦 ∈ 𝑆 (𝑦 ⚬ 𝑥) = 𝑦 ↔ (((𝐴 ⚬ 𝐴) = 𝐴 ∧ (𝐵 ⚬ 𝐴) = 𝐵) ∧ ((𝐴 ⚬ 𝐵) = 𝐴 ∧ (𝐵 ⚬ 𝐵) = 𝐵))))
60	35, 59	mpbird 247	1 ⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → ∀𝑥 ∈ 𝑆 ∀𝑦 ∈ 𝑆 (𝑦 ⚬ 𝑥) = 𝑦)

Syntax hints:  ¬ wn 3   → wi 4   ∧ wa 384   = wceq 1483   ∈ wcel 1990   ≠ wne 2794  ∀wral 2912  ifcif 4086  {cpr 4179  ‘cfv 5888  (class class class)co 6650   ↦ cmpt2 6652  Basecbs 15857  +_gcplusg 15941

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1722  ax-4 1737  ax-5 1839  ax-6 1888  ax-7 1935  ax-9 1999  ax-10 2019  ax-11 2034  ax-12 2047  ax-13 2246  ax-ext 2602  ax-sep 4781  ax-nul 4789  ax-pr 4906

This theorem depends on definitions:  df-bi 197  df-or 385  df-an 386  df-3an 1039  df-tru 1486  df-ex 1705  df-nf 1710  df-sb 1881  df-eu 2474  df-mo 2475  df-clab 2609  df-cleq 2615  df-clel 2618  df-nfc 2753  df-ne 2795  df-ral 2917  df-rex 2918  df-rab 2921  df-v 3202  df-sbc 3436  df-dif 3577  df-un 3579  df-in 3581  df-ss 3588  df-nul 3916  df-if 4087  df-sn 4178  df-pr 4180  df-op 4184  df-uni 4437  df-br 4654  df-opab 4713  df-id 5024  df-xp 5120  df-rel 5121  df-cnv 5122  df-co 5123  df-dm 5124  df-iota 5851  df-fun 5890  df-fv 5896  df-ov 6653  df-oprab 6654  df-mpt2 6655

This theorem is referenced by:  sgrp2rid2ex  17414