Theorem cuteq0 27807

Description: Condition for a surreal cut to equal zero. (Contributed by Scott Fenton, 3-Feb-2025.)

Hypotheses

Ref	Expression
cuteq0.1	⊢ (𝜑 → 𝐴 <<s { 0s })
cuteq0.2	⊢ (𝜑 → { 0s } <<s 𝐵)

Assertion

Ref	Expression
cuteq0	⊢ (𝜑 → (𝐴 |s 𝐵) = 0s )

Proof of Theorem cuteq0

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

Step	Hyp	Ref	Expression
1		cuteq0.1	. 2 ⊢ (𝜑 → 𝐴 <<s { 0s })
2		cuteq0.2	. 2 ⊢ (𝜑 → { 0s } <<s 𝐵)
3		bday0 27803	. . 3 ⊢ ( bday ‘ 0s ) = ∅
4	3	a1i 11	. . . . . 6 ⊢ (𝜑 → ( bday ‘ 0s ) = ∅)
5		0no 27801	. . . . . . 7 ⊢ 0s ∈ No
6		sneq 4578	. . . . . . . . . . 11 ⊢ (𝑦 = 0s → {𝑦} = { 0s })
7	6	breq2d 5098	. . . . . . . . . 10 ⊢ (𝑦 = 0s → (𝐴 <<s {𝑦} ↔ 𝐴 <<s { 0s }))
8	6	breq1d 5096	. . . . . . . . . 10 ⊢ (𝑦 = 0s → ({𝑦} <<s 𝐵 ↔ { 0s } <<s 𝐵))
9	7, 8	anbi12d 633	. . . . . . . . 9 ⊢ (𝑦 = 0s → ((𝐴 <<s {𝑦} ∧ {𝑦} <<s 𝐵) ↔ (𝐴 <<s { 0s } ∧ { 0s } <<s 𝐵)))
10		fveqeq2 6850	. . . . . . . . 9 ⊢ (𝑦 = 0s → (( bday ‘𝑦) = ∅ ↔ ( bday ‘ 0s ) = ∅))
11	9, 10	anbi12d 633	. . . . . . . 8 ⊢ (𝑦 = 0s → (((𝐴 <<s {𝑦} ∧ {𝑦} <<s 𝐵) ∧ ( bday ‘𝑦) = ∅) ↔ ((𝐴 <<s { 0s } ∧ { 0s } <<s 𝐵) ∧ ( bday ‘ 0s ) = ∅)))
12	11	rspcev 3565	. . . . . . 7 ⊢ (( 0s ∈ No ∧ ((𝐴 <<s { 0s } ∧ { 0s } <<s 𝐵) ∧ ( bday ‘ 0s ) = ∅)) → ∃𝑦 ∈ No ((𝐴 <<s {𝑦} ∧ {𝑦} <<s 𝐵) ∧ ( bday ‘𝑦) = ∅))
13	5, 12	mpan 691	. . . . . 6 ⊢ (((𝐴 <<s { 0s } ∧ { 0s } <<s 𝐵) ∧ ( bday ‘ 0s ) = ∅) → ∃𝑦 ∈ No ((𝐴 <<s {𝑦} ∧ {𝑦} <<s 𝐵) ∧ ( bday ‘𝑦) = ∅))
14	1, 2, 4, 13	syl21anc 838	. . . . 5 ⊢ (𝜑 → ∃𝑦 ∈ No ((𝐴 <<s {𝑦} ∧ {𝑦} <<s 𝐵) ∧ ( bday ‘𝑦) = ∅))
15		bdayfn 27741	. . . . . . 7 ⊢ bday Fn No
16		ssrab2 4021	. . . . . . 7 ⊢ {𝑥 ∈ No ∣ (𝐴 <<s {𝑥} ∧ {𝑥} <<s 𝐵)} ⊆ No
17		fvelimab 6913	. . . . . . 7 ⊢ (( bday Fn No ∧ {𝑥 ∈ No ∣ (𝐴 <<s {𝑥} ∧ {𝑥} <<s 𝐵)} ⊆ No ) → (∅ ∈ ( bday “ {𝑥 ∈ No ∣ (𝐴 <<s {𝑥} ∧ {𝑥} <<s 𝐵)}) ↔ ∃𝑦 ∈ {𝑥 ∈ No ∣ (𝐴 <<s {𝑥} ∧ {𝑥} <<s 𝐵)} ( bday ‘𝑦) = ∅))
18	15, 16, 17	mp2an 693	. . . . . 6 ⊢ (∅ ∈ ( bday “ {𝑥 ∈ No ∣ (𝐴 <<s {𝑥} ∧ {𝑥} <<s 𝐵)}) ↔ ∃𝑦 ∈ {𝑥 ∈ No ∣ (𝐴 <<s {𝑥} ∧ {𝑥} <<s 𝐵)} ( bday ‘𝑦) = ∅)
19		sneq 4578	. . . . . . . . 9 ⊢ (𝑥 = 𝑦 → {𝑥} = {𝑦})
20	19	breq2d 5098	. . . . . . . 8 ⊢ (𝑥 = 𝑦 → (𝐴 <<s {𝑥} ↔ 𝐴 <<s {𝑦}))
21	19	breq1d 5096	. . . . . . . 8 ⊢ (𝑥 = 𝑦 → ({𝑥} <<s 𝐵 ↔ {𝑦} <<s 𝐵))
22	20, 21	anbi12d 633	. . . . . . 7 ⊢ (𝑥 = 𝑦 → ((𝐴 <<s {𝑥} ∧ {𝑥} <<s 𝐵) ↔ (𝐴 <<s {𝑦} ∧ {𝑦} <<s 𝐵)))
23	22	rexrab 3643	. . . . . 6 ⊢ (∃𝑦 ∈ {𝑥 ∈ No ∣ (𝐴 <<s {𝑥} ∧ {𝑥} <<s 𝐵)} ( bday ‘𝑦) = ∅ ↔ ∃𝑦 ∈ No ((𝐴 <<s {𝑦} ∧ {𝑦} <<s 𝐵) ∧ ( bday ‘𝑦) = ∅))
24	18, 23	bitri 275	. . . . 5 ⊢ (∅ ∈ ( bday “ {𝑥 ∈ No ∣ (𝐴 <<s {𝑥} ∧ {𝑥} <<s 𝐵)}) ↔ ∃𝑦 ∈ No ((𝐴 <<s {𝑦} ∧ {𝑦} <<s 𝐵) ∧ ( bday ‘𝑦) = ∅))
25	14, 24	sylibr 234	. . . 4 ⊢ (𝜑 → ∅ ∈ ( bday “ {𝑥 ∈ No ∣ (𝐴 <<s {𝑥} ∧ {𝑥} <<s 𝐵)}))
26		int0el 4922	. . . 4 ⊢ (∅ ∈ ( bday “ {𝑥 ∈ No ∣ (𝐴 <<s {𝑥} ∧ {𝑥} <<s 𝐵)}) → ∩ ( bday “ {𝑥 ∈ No ∣ (𝐴 <<s {𝑥} ∧ {𝑥} <<s 𝐵)}) = ∅)
27	25, 26	syl 17	. . 3 ⊢ (𝜑 → ∩ ( bday “ {𝑥 ∈ No ∣ (𝐴 <<s {𝑥} ∧ {𝑥} <<s 𝐵)}) = ∅)
28	3, 27	eqtr4id 2791	. 2 ⊢ (𝜑 → ( bday ‘ 0s ) = ∩ ( bday “ {𝑥 ∈ No ∣ (𝐴 <<s {𝑥} ∧ {𝑥} <<s 𝐵)}))
29	5	elexi 3453	. . . . . 6 ⊢ 0s ∈ V
30	29	snnz 4721	. . . . 5 ⊢ { 0s } ≠ ∅
31		sltstr 27779	. . . . 5 ⊢ ((𝐴 <<s { 0s } ∧ { 0s } <<s 𝐵 ∧ { 0s } ≠ ∅) → 𝐴 <<s 𝐵)
32	30, 31	mp3an3 1453	. . . 4 ⊢ ((𝐴 <<s { 0s } ∧ { 0s } <<s 𝐵) → 𝐴 <<s 𝐵)
33	1, 2, 32	syl2anc 585	. . 3 ⊢ (𝜑 → 𝐴 <<s 𝐵)
34		eqcuts 27777	. . 3 ⊢ ((𝐴 <<s 𝐵 ∧ 0s ∈ No ) → ((𝐴 |s 𝐵) = 0s ↔ (𝐴 <<s { 0s } ∧ { 0s } <<s 𝐵 ∧ ( bday ‘ 0s ) = ∩ ( bday “ {𝑥 ∈ No ∣ (𝐴 <<s {𝑥} ∧ {𝑥} <<s 𝐵)}))))
35	33, 5, 34	sylancl 587	. 2 ⊢ (𝜑 → ((𝐴 |s 𝐵) = 0s ↔ (𝐴 <<s { 0s } ∧ { 0s } <<s 𝐵 ∧ ( bday ‘ 0s ) = ∩ ( bday “ {𝑥 ∈ No ∣ (𝐴 <<s {𝑥} ∧ {𝑥} <<s 𝐵)}))))
36	1, 2, 28, 35	mpbir3and 1344	1 ⊢ (𝜑 → (𝐴 |s 𝐵) = 0s )

Syntax hints:   → wi 4   ↔ wb 206   ∧ wa 395   ∧ w3a 1087   = wceq 1542   ∈ wcel 2114   ≠ wne 2933  ∃wrex 3062  {crab 3390   ⊆ wss 3890  ∅c0 4274  {csn 4568  ∩ cint 4890   class class class wbr 5086   “ cima 5634   Fn wfn 6494  ‘cfv 6499  (class class class)co 7367   No csur 27603   bday cbday 27605   <<s cslts 27749   |s ccuts 27751   0_s c0s 27797

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1912  ax-6 1969  ax-7 2010  ax-8 2116  ax-9 2124  ax-10 2147  ax-11 2163  ax-12 2185  ax-ext 2709  ax-rep 5213  ax-sep 5232  ax-nul 5242  ax-pow 5308  ax-pr 5376  ax-un 7689

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 849  df-3or 1088  df-3an 1089  df-tru 1545  df-fal 1555  df-ex 1782  df-nf 1786  df-sb 2069  df-mo 2540  df-eu 2570  df-clab 2716  df-cleq 2729  df-clel 2812  df-nfc 2886  df-ne 2934  df-ral 3053  df-rex 3063  df-rmo 3343  df-reu 3344  df-rab 3391  df-v 3432  df-sbc 3730  df-csb 3839  df-dif 3893  df-un 3895  df-in 3897  df-ss 3907  df-pss 3910  df-nul 4275  df-if 4468  df-pw 4544  df-sn 4569  df-pr 4571  df-tp 4573  df-op 4575  df-uni 4852  df-int 4891  df-br 5087  df-opab 5149  df-mpt 5168  df-tr 5194  df-id 5526  df-eprel 5531  df-po 5539  df-so 5540  df-fr 5584  df-we 5586  df-xp 5637  df-rel 5638  df-cnv 5639  df-co 5640  df-dm 5641  df-rn 5642  df-res 5643  df-ima 5644  df-ord 6327  df-on 6328  df-suc 6330  df-iota 6455  df-fun 6501  df-fn 6502  df-f 6503  df-f1 6504  df-fo 6505  df-f1o 6506  df-fv 6507  df-riota 7324  df-ov 7370  df-oprab 7371  df-mpo 7372  df-1o 8405  df-2o 8406  df-no 27606  df-lts 27607  df-bday 27608  df-slts 27750  df-cuts 27752  df-0s 27799

This theorem is referenced by:  cutneg  27808  negsid  28033