Theorem altopthsn 35945

Description: Two alternate ordered pairs are equal iff the singletons of their respective elements are equal. Note that this holds regardless of sethood of any of the elements. (Contributed by Scott Fenton, 16-Apr-2012.)

Assertion

Ref	Expression
altopthsn	⊢ (⟪𝐴, 𝐵⟫ = ⟪𝐶, 𝐷⟫ ↔ ({𝐴} = {𝐶} ∧ {𝐵} = {𝐷}))

Proof of Theorem altopthsn

Step	Hyp	Ref	Expression
1		df-altop 35942	. . 3 ⊢ ⟪𝐴, 𝐵⟫ = {{𝐴}, {𝐴, {𝐵}}}
2		df-altop 35942	. . 3 ⊢ ⟪𝐶, 𝐷⟫ = {{𝐶}, {𝐶, {𝐷}}}
3	1, 2	eqeq12i 2747	. 2 ⊢ (⟪𝐴, 𝐵⟫ = ⟪𝐶, 𝐷⟫ ↔ {{𝐴}, {𝐴, {𝐵}}} = {{𝐶}, {𝐶, {𝐷}}})
4		snex 5375	. . . . . 6 ⊢ {𝐴} ∈ V
5		prex 5376	. . . . . 6 ⊢ {𝐴, {𝐵}} ∈ V
6		snex 5375	. . . . . 6 ⊢ {𝐶} ∈ V
7		prex 5376	. . . . . 6 ⊢ {𝐶, {𝐷}} ∈ V
8	4, 5, 6, 7	preq12b 4801	. . . . 5 ⊢ ({{𝐴}, {𝐴, {𝐵}}} = {{𝐶}, {𝐶, {𝐷}}} ↔ (({𝐴} = {𝐶} ∧ {𝐴, {𝐵}} = {𝐶, {𝐷}}) ∨ ({𝐴} = {𝐶, {𝐷}} ∧ {𝐴, {𝐵}} = {𝐶})))
9		simpl 482	. . . . . 6 ⊢ (({𝐴} = {𝐶} ∧ {𝐴, {𝐵}} = {𝐶, {𝐷}}) → {𝐴} = {𝐶})
10		snsspr1 4765	. . . . . . . . 9 ⊢ {𝐴} ⊆ {𝐴, {𝐵}}
11		sseq2 3962	. . . . . . . . 9 ⊢ ({𝐴, {𝐵}} = {𝐶} → ({𝐴} ⊆ {𝐴, {𝐵}} ↔ {𝐴} ⊆ {𝐶}))
12	10, 11	mpbii 233	. . . . . . . 8 ⊢ ({𝐴, {𝐵}} = {𝐶} → {𝐴} ⊆ {𝐶})
13	12	adantl 481	. . . . . . 7 ⊢ (({𝐴} = {𝐶, {𝐷}} ∧ {𝐴, {𝐵}} = {𝐶}) → {𝐴} ⊆ {𝐶})
14		snsspr1 4765	. . . . . . . . 9 ⊢ {𝐶} ⊆ {𝐶, {𝐷}}
15		sseq2 3962	. . . . . . . . 9 ⊢ ({𝐴} = {𝐶, {𝐷}} → ({𝐶} ⊆ {𝐴} ↔ {𝐶} ⊆ {𝐶, {𝐷}}))
16	14, 15	mpbiri 258	. . . . . . . 8 ⊢ ({𝐴} = {𝐶, {𝐷}} → {𝐶} ⊆ {𝐴})
17	16	adantr 480	. . . . . . 7 ⊢ (({𝐴} = {𝐶, {𝐷}} ∧ {𝐴, {𝐵}} = {𝐶}) → {𝐶} ⊆ {𝐴})
18	13, 17	eqssd 3953	. . . . . 6 ⊢ (({𝐴} = {𝐶, {𝐷}} ∧ {𝐴, {𝐵}} = {𝐶}) → {𝐴} = {𝐶})
19	9, 18	jaoi 857	. . . . 5 ⊢ ((({𝐴} = {𝐶} ∧ {𝐴, {𝐵}} = {𝐶, {𝐷}}) ∨ ({𝐴} = {𝐶, {𝐷}} ∧ {𝐴, {𝐵}} = {𝐶})) → {𝐴} = {𝐶})
20	8, 19	sylbi 217	. . . 4 ⊢ ({{𝐴}, {𝐴, {𝐵}}} = {{𝐶}, {𝐶, {𝐷}}} → {𝐴} = {𝐶})
21		uneq1 4112	. . . . . . . . . 10 ⊢ ({𝐴} = {𝐶} → ({𝐴} ∪ {{𝐵}}) = ({𝐶} ∪ {{𝐵}}))
22		df-pr 4580	. . . . . . . . . 10 ⊢ {𝐴, {𝐵}} = ({𝐴} ∪ {{𝐵}})
23		df-pr 4580	. . . . . . . . . 10 ⊢ {𝐶, {𝐵}} = ({𝐶} ∪ {{𝐵}})
24	21, 22, 23	3eqtr4g 2789	. . . . . . . . 9 ⊢ ({𝐴} = {𝐶} → {𝐴, {𝐵}} = {𝐶, {𝐵}})
25	24	preq2d 4692	. . . . . . . 8 ⊢ ({𝐴} = {𝐶} → {{𝐴}, {𝐴, {𝐵}}} = {{𝐴}, {𝐶, {𝐵}}})
26		preq1 4685	. . . . . . . 8 ⊢ ({𝐴} = {𝐶} → {{𝐴}, {𝐶, {𝐵}}} = {{𝐶}, {𝐶, {𝐵}}})
27	25, 26	eqtrd 2764	. . . . . . 7 ⊢ ({𝐴} = {𝐶} → {{𝐴}, {𝐴, {𝐵}}} = {{𝐶}, {𝐶, {𝐵}}})
28	27	eqeq1d 2731	. . . . . 6 ⊢ ({𝐴} = {𝐶} → ({{𝐴}, {𝐴, {𝐵}}} = {{𝐶}, {𝐶, {𝐷}}} ↔ {{𝐶}, {𝐶, {𝐵}}} = {{𝐶}, {𝐶, {𝐷}}}))
29	28	biimpd 229	. . . . 5 ⊢ ({𝐴} = {𝐶} → ({{𝐴}, {𝐴, {𝐵}}} = {{𝐶}, {𝐶, {𝐷}}} → {{𝐶}, {𝐶, {𝐵}}} = {{𝐶}, {𝐶, {𝐷}}}))
30		prex 5376	. . . . . . 7 ⊢ {𝐶, {𝐵}} ∈ V
31	30, 7	preqr2 4800	. . . . . 6 ⊢ ({{𝐶}, {𝐶, {𝐵}}} = {{𝐶}, {𝐶, {𝐷}}} → {𝐶, {𝐵}} = {𝐶, {𝐷}})
32		snex 5375	. . . . . . 7 ⊢ {𝐵} ∈ V
33		snex 5375	. . . . . . 7 ⊢ {𝐷} ∈ V
34	32, 33	preqr2 4800	. . . . . 6 ⊢ ({𝐶, {𝐵}} = {𝐶, {𝐷}} → {𝐵} = {𝐷})
35	31, 34	syl 17	. . . . 5 ⊢ ({{𝐶}, {𝐶, {𝐵}}} = {{𝐶}, {𝐶, {𝐷}}} → {𝐵} = {𝐷})
36	29, 35	syl6com 37	. . . 4 ⊢ ({{𝐴}, {𝐴, {𝐵}}} = {{𝐶}, {𝐶, {𝐷}}} → ({𝐴} = {𝐶} → {𝐵} = {𝐷}))
37	20, 36	jcai 516	. . 3 ⊢ ({{𝐴}, {𝐴, {𝐵}}} = {{𝐶}, {𝐶, {𝐷}}} → ({𝐴} = {𝐶} ∧ {𝐵} = {𝐷}))
38		preq2 4686	. . . . 5 ⊢ ({𝐵} = {𝐷} → {𝐶, {𝐵}} = {𝐶, {𝐷}})
39	38	preq2d 4692	. . . 4 ⊢ ({𝐵} = {𝐷} → {{𝐶}, {𝐶, {𝐵}}} = {{𝐶}, {𝐶, {𝐷}}})
40	27, 39	sylan9eq 2784	. . 3 ⊢ (({𝐴} = {𝐶} ∧ {𝐵} = {𝐷}) → {{𝐴}, {𝐴, {𝐵}}} = {{𝐶}, {𝐶, {𝐷}}})
41	37, 40	impbii 209	. 2 ⊢ ({{𝐴}, {𝐴, {𝐵}}} = {{𝐶}, {𝐶, {𝐷}}} ↔ ({𝐴} = {𝐶} ∧ {𝐵} = {𝐷}))
42	3, 41	bitri 275	1 ⊢ (⟪𝐴, 𝐵⟫ = ⟪𝐶, 𝐷⟫ ↔ ({𝐴} = {𝐶} ∧ {𝐵} = {𝐷}))

Syntax hints:   ↔ wb 206   ∧ wa 395   ∨ wo 847   = wceq 1540   ∪ cun 3901   ⊆ wss 3903  {csn 4577  {cpr 4579  ⟪caltop 35940

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1795  ax-4 1809  ax-5 1910  ax-6 1967  ax-7 2008  ax-8 2111  ax-9 2119  ax-ext 2701  ax-sep 5235  ax-nul 5245  ax-pr 5371

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-tru 1543  df-fal 1553  df-ex 1780  df-sb 2066  df-clab 2708  df-cleq 2721  df-clel 2803  df-v 3438  df-dif 3906  df-un 3908  df-ss 3920  df-nul 4285  df-sn 4578  df-pr 4580  df-altop 35942

This theorem is referenced by:  altopeq12  35946  altopth1  35949  altopth2  35950  altopthg  35951  altopthbg  35952