Theorem lrold 34004

Description: The union of the left and right options of a surreal make its old set. (Contributed by Scott Fenton, 9-Oct-2024.)

Assertion

Ref	Expression
lrold	⊢ (( L ‘𝐴) ∪ ( R ‘𝐴)) = ( O ‘( bday ‘𝐴))

Proof of Theorem lrold

Dummy variable 𝑥 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		leftval 33974	. . . . 5 ⊢ ( L ‘𝐴) = {𝑥 ∈ ( O ‘( bday ‘𝐴)) ∣ 𝑥 <s 𝐴}
2		rightval 33975	. . . . 5 ⊢ ( R ‘𝐴) = {𝑥 ∈ ( O ‘( bday ‘𝐴)) ∣ 𝐴 <s 𝑥}
3	1, 2	uneq12i 4091	. . . 4 ⊢ (( L ‘𝐴) ∪ ( R ‘𝐴)) = ({𝑥 ∈ ( O ‘( bday ‘𝐴)) ∣ 𝑥 <s 𝐴} ∪ {𝑥 ∈ ( O ‘( bday ‘𝐴)) ∣ 𝐴 <s 𝑥})
4		unrab 4236	. . . 4 ⊢ ({𝑥 ∈ ( O ‘( bday ‘𝐴)) ∣ 𝑥 <s 𝐴} ∪ {𝑥 ∈ ( O ‘( bday ‘𝐴)) ∣ 𝐴 <s 𝑥}) = {𝑥 ∈ ( O ‘( bday ‘𝐴)) ∣ (𝑥 <s 𝐴 ∨ 𝐴 <s 𝑥)}
5	3, 4	eqtri 2766	. . 3 ⊢ (( L ‘𝐴) ∪ ( R ‘𝐴)) = {𝑥 ∈ ( O ‘( bday ‘𝐴)) ∣ (𝑥 <s 𝐴 ∨ 𝐴 <s 𝑥)}
6		oldirr 33999	. . . . . . . 8 ⊢ ¬ 𝐴 ∈ ( O ‘( bday ‘𝐴))
7		eleq1 2826	. . . . . . . 8 ⊢ (𝑥 = 𝐴 → (𝑥 ∈ ( O ‘( bday ‘𝐴)) ↔ 𝐴 ∈ ( O ‘( bday ‘𝐴))))
8	6, 7	mtbiri 326	. . . . . . 7 ⊢ (𝑥 = 𝐴 → ¬ 𝑥 ∈ ( O ‘( bday ‘𝐴)))
9	8	necon2ai 2972	. . . . . 6 ⊢ (𝑥 ∈ ( O ‘( bday ‘𝐴)) → 𝑥 ≠ 𝐴)
10	9	adantl 481	. . . . 5 ⊢ ((𝐴 ∈ No ∧ 𝑥 ∈ ( O ‘( bday ‘𝐴))) → 𝑥 ≠ 𝐴)
11		oldssno 33972	. . . . . . 7 ⊢ ( O ‘( bday ‘𝐴)) ⊆ No
12	11	sseli 3913	. . . . . 6 ⊢ (𝑥 ∈ ( O ‘( bday ‘𝐴)) → 𝑥 ∈ No )
13		slttrine 33881	. . . . . . 7 ⊢ ((𝑥 ∈ No ∧ 𝐴 ∈ No ) → (𝑥 ≠ 𝐴 ↔ (𝑥 <s 𝐴 ∨ 𝐴 <s 𝑥)))
14	13	ancoms 458	. . . . . 6 ⊢ ((𝐴 ∈ No ∧ 𝑥 ∈ No ) → (𝑥 ≠ 𝐴 ↔ (𝑥 <s 𝐴 ∨ 𝐴 <s 𝑥)))
15	12, 14	sylan2 592	. . . . 5 ⊢ ((𝐴 ∈ No ∧ 𝑥 ∈ ( O ‘( bday ‘𝐴))) → (𝑥 ≠ 𝐴 ↔ (𝑥 <s 𝐴 ∨ 𝐴 <s 𝑥)))
16	10, 15	mpbid 231	. . . 4 ⊢ ((𝐴 ∈ No ∧ 𝑥 ∈ ( O ‘( bday ‘𝐴))) → (𝑥 <s 𝐴 ∨ 𝐴 <s 𝑥))
17	16	rabeqcda 3419	. . 3 ⊢ (𝐴 ∈ No → {𝑥 ∈ ( O ‘( bday ‘𝐴)) ∣ (𝑥 <s 𝐴 ∨ 𝐴 <s 𝑥)} = ( O ‘( bday ‘𝐴)))
18	5, 17	syl5eq 2791	. 2 ⊢ (𝐴 ∈ No → (( L ‘𝐴) ∪ ( R ‘𝐴)) = ( O ‘( bday ‘𝐴)))
19		un0 4321	. . 3 ⊢ (∅ ∪ ∅) = ∅
20		leftf 33976	. . . . . . 7 ⊢ L : No ⟶𝒫 No
21	20	fdmi 6596	. . . . . 6 ⊢ dom L = No
22	21	eleq2i 2830	. . . . 5 ⊢ (𝐴 ∈ dom L ↔ 𝐴 ∈ No )
23		ndmfv 6786	. . . . 5 ⊢ (¬ 𝐴 ∈ dom L → ( L ‘𝐴) = ∅)
24	22, 23	sylnbir 330	. . . 4 ⊢ (¬ 𝐴 ∈ No → ( L ‘𝐴) = ∅)
25		rightf 33977	. . . . . . 7 ⊢ R : No ⟶𝒫 No
26	25	fdmi 6596	. . . . . 6 ⊢ dom R = No
27	26	eleq2i 2830	. . . . 5 ⊢ (𝐴 ∈ dom R ↔ 𝐴 ∈ No )
28		ndmfv 6786	. . . . 5 ⊢ (¬ 𝐴 ∈ dom R → ( R ‘𝐴) = ∅)
29	27, 28	sylnbir 330	. . . 4 ⊢ (¬ 𝐴 ∈ No → ( R ‘𝐴) = ∅)
30	24, 29	uneq12d 4094	. . 3 ⊢ (¬ 𝐴 ∈ No → (( L ‘𝐴) ∪ ( R ‘𝐴)) = (∅ ∪ ∅))
31		bdaydm 33896	. . . . . . 7 ⊢ dom bday = No
32	31	eleq2i 2830	. . . . . 6 ⊢ (𝐴 ∈ dom bday ↔ 𝐴 ∈ No )
33		ndmfv 6786	. . . . . 6 ⊢ (¬ 𝐴 ∈ dom bday → ( bday ‘𝐴) = ∅)
34	32, 33	sylnbir 330	. . . . 5 ⊢ (¬ 𝐴 ∈ No → ( bday ‘𝐴) = ∅)
35	34	fveq2d 6760	. . . 4 ⊢ (¬ 𝐴 ∈ No → ( O ‘( bday ‘𝐴)) = ( O ‘∅))
36		old0 33970	. . . 4 ⊢ ( O ‘∅) = ∅
37	35, 36	eqtrdi 2795	. . 3 ⊢ (¬ 𝐴 ∈ No → ( O ‘( bday ‘𝐴)) = ∅)
38	19, 30, 37	3eqtr4a 2805	. 2 ⊢ (¬ 𝐴 ∈ No → (( L ‘𝐴) ∪ ( R ‘𝐴)) = ( O ‘( bday ‘𝐴)))
39	18, 38	pm2.61i 182	1 ⊢ (( L ‘𝐴) ∪ ( R ‘𝐴)) = ( O ‘( bday ‘𝐴))

Syntax hints:  ¬ wn 3   ↔ wb 205   ∧ wa 395   ∨ wo 843   = wceq 1539   ∈ wcel 2108   ≠ wne 2942  {crab 3067   ∪ cun 3881  ∅c0 4253  𝒫 cpw 4530   class class class wbr 5070  dom cdm 5580  ‘cfv 6418   No csur 33770   <s cslt 33771   bday cbday 33772   O cold 33954   L cleft 33956   R cright 33957

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1799  ax-4 1813  ax-5 1914  ax-6 1972  ax-7 2012  ax-8 2110  ax-9 2118  ax-10 2139  ax-11 2156  ax-12 2173  ax-ext 2709  ax-rep 5205  ax-sep 5218  ax-nul 5225  ax-pow 5283  ax-pr 5347  ax-un 7566

This theorem depends on definitions:  df-bi 206  df-an 396  df-or 844  df-3or 1086  df-3an 1087  df-tru 1542  df-fal 1552  df-ex 1784  df-nf 1788  df-sb 2069  df-mo 2540  df-eu 2569  df-clab 2716  df-cleq 2730  df-clel 2817  df-nfc 2888  df-ne 2943  df-ral 3068  df-rex 3069  df-reu 3070  df-rmo 3071  df-rab 3072  df-v 3424  df-sbc 3712  df-csb 3829  df-dif 3886  df-un 3888  df-in 3890  df-ss 3900  df-pss 3902  df-nul 4254  df-if 4457  df-pw 4532  df-sn 4559  df-pr 4561  df-tp 4563  df-op 4565  df-uni 4837  df-int 4877  df-iun 4923  df-br 5071  df-opab 5133  df-mpt 5154  df-tr 5188  df-id 5480  df-eprel 5486  df-po 5494  df-so 5495  df-fr 5535  df-we 5537  df-xp 5586  df-rel 5587  df-cnv 5588  df-co 5589  df-dm 5590  df-rn 5591  df-res 5592  df-ima 5593  df-pred 6191  df-ord 6254  df-on 6255  df-suc 6257  df-iota 6376  df-fun 6420  df-fn 6421  df-f 6422  df-f1 6423  df-fo 6424  df-f1o 6425  df-fv 6426  df-riota 7212  df-ov 7258  df-oprab 7259  df-mpo 7260  df-2nd 7805  df-frecs 8068  df-wrecs 8099  df-recs 8173  df-1o 8267  df-2o 8268  df-no 33773  df-slt 33774  df-bday 33775  df-sslt 33903  df-scut 33905  df-made 33958  df-old 33959  df-left 33961  df-right 33962

This theorem is referenced by:  lruneq  34013  lrrecval2  34024