Theorem nntri3 6582

Description: A trichotomy law for natural numbers. (Contributed by Jim Kingdon, 15-May-2020.)

Assertion

Ref	Expression
nntri3	⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ ω) → (𝐴 = 𝐵 ↔ (¬ 𝐴 ∈ 𝐵 ∧ ¬ 𝐵 ∈ 𝐴)))

Proof of Theorem nntri3

Step	Hyp	Ref	Expression
1		elirr 4588	. . . . . 6 ⊢ ¬ 𝐴 ∈ 𝐴
2		eleq2 2268	. . . . . 6 ⊢ (𝐴 = 𝐵 → (𝐴 ∈ 𝐴 ↔ 𝐴 ∈ 𝐵))
3	1, 2	mtbii 675	. . . . 5 ⊢ (𝐴 = 𝐵 → ¬ 𝐴 ∈ 𝐵)
4	3	con2i 628	. . . 4 ⊢ (𝐴 ∈ 𝐵 → ¬ 𝐴 = 𝐵)
5	4	adantl 277	. . 3 ⊢ (((𝐴 ∈ ω ∧ 𝐵 ∈ ω) ∧ 𝐴 ∈ 𝐵) → ¬ 𝐴 = 𝐵)
6		simpl 109	. . . . 5 ⊢ ((¬ 𝐴 ∈ 𝐵 ∧ ¬ 𝐵 ∈ 𝐴) → ¬ 𝐴 ∈ 𝐵)
7	6	con2i 628	. . . 4 ⊢ (𝐴 ∈ 𝐵 → ¬ (¬ 𝐴 ∈ 𝐵 ∧ ¬ 𝐵 ∈ 𝐴))
8	7	adantl 277	. . 3 ⊢ (((𝐴 ∈ ω ∧ 𝐵 ∈ ω) ∧ 𝐴 ∈ 𝐵) → ¬ (¬ 𝐴 ∈ 𝐵 ∧ ¬ 𝐵 ∈ 𝐴))
9	5, 8	2falsed 703	. 2 ⊢ (((𝐴 ∈ ω ∧ 𝐵 ∈ ω) ∧ 𝐴 ∈ 𝐵) → (𝐴 = 𝐵 ↔ (¬ 𝐴 ∈ 𝐵 ∧ ¬ 𝐵 ∈ 𝐴)))
10		simpr 110	. . 3 ⊢ (((𝐴 ∈ ω ∧ 𝐵 ∈ ω) ∧ 𝐴 = 𝐵) → 𝐴 = 𝐵)
11		eleq1 2267	. . . . . 6 ⊢ (𝐴 = 𝐵 → (𝐴 ∈ 𝐴 ↔ 𝐵 ∈ 𝐴))
12	1, 11	mtbii 675	. . . . 5 ⊢ (𝐴 = 𝐵 → ¬ 𝐵 ∈ 𝐴)
13	3, 12	jca 306	. . . 4 ⊢ (𝐴 = 𝐵 → (¬ 𝐴 ∈ 𝐵 ∧ ¬ 𝐵 ∈ 𝐴))
14	13	adantl 277	. . 3 ⊢ (((𝐴 ∈ ω ∧ 𝐵 ∈ ω) ∧ 𝐴 = 𝐵) → (¬ 𝐴 ∈ 𝐵 ∧ ¬ 𝐵 ∈ 𝐴))
15	10, 14	2thd 175	. 2 ⊢ (((𝐴 ∈ ω ∧ 𝐵 ∈ ω) ∧ 𝐴 = 𝐵) → (𝐴 = 𝐵 ↔ (¬ 𝐴 ∈ 𝐵 ∧ ¬ 𝐵 ∈ 𝐴)))
16	12	con2i 628	. . . 4 ⊢ (𝐵 ∈ 𝐴 → ¬ 𝐴 = 𝐵)
17	16	adantl 277	. . 3 ⊢ (((𝐴 ∈ ω ∧ 𝐵 ∈ ω) ∧ 𝐵 ∈ 𝐴) → ¬ 𝐴 = 𝐵)
18		simpr 110	. . . . 5 ⊢ ((¬ 𝐴 ∈ 𝐵 ∧ ¬ 𝐵 ∈ 𝐴) → ¬ 𝐵 ∈ 𝐴)
19	18	con2i 628	. . . 4 ⊢ (𝐵 ∈ 𝐴 → ¬ (¬ 𝐴 ∈ 𝐵 ∧ ¬ 𝐵 ∈ 𝐴))
20	19	adantl 277	. . 3 ⊢ (((𝐴 ∈ ω ∧ 𝐵 ∈ ω) ∧ 𝐵 ∈ 𝐴) → ¬ (¬ 𝐴 ∈ 𝐵 ∧ ¬ 𝐵 ∈ 𝐴))
21	17, 20	2falsed 703	. 2 ⊢ (((𝐴 ∈ ω ∧ 𝐵 ∈ ω) ∧ 𝐵 ∈ 𝐴) → (𝐴 = 𝐵 ↔ (¬ 𝐴 ∈ 𝐵 ∧ ¬ 𝐵 ∈ 𝐴)))
22		nntri3or 6578	. 2 ⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ ω) → (𝐴 ∈ 𝐵 ∨ 𝐴 = 𝐵 ∨ 𝐵 ∈ 𝐴))
23	9, 15, 21, 22	mpjao3dan 1319	1 ⊢ ((𝐴 ∈ ω ∧ 𝐵 ∈ ω) → (𝐴 = 𝐵 ↔ (¬ 𝐴 ∈ 𝐵 ∧ ¬ 𝐵 ∈ 𝐴)))

Syntax hints:  ¬ wn 3   → wi 4   ∧ wa 104   ↔ wb 105   = wceq 1372   ∈ wcel 2175  ωcom 4637

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 615  ax-in2 616  ax-io 710  ax-5 1469  ax-7 1470  ax-gen 1471  ax-ie1 1515  ax-ie2 1516  ax-8 1526  ax-10 1527  ax-11 1528  ax-i12 1529  ax-bndl 1531  ax-4 1532  ax-17 1548  ax-i9 1552  ax-ial 1556  ax-i5r 1557  ax-13 2177  ax-14 2178  ax-ext 2186  ax-sep 4161  ax-nul 4169  ax-pow 4217  ax-pr 4252  ax-un 4479  ax-setind 4584  ax-iinf 4635

This theorem depends on definitions:  df-bi 117  df-3or 981  df-3an 982  df-tru 1375  df-nf 1483  df-sb 1785  df-clab 2191  df-cleq 2197  df-clel 2200  df-nfc 2336  df-ne 2376  df-ral 2488  df-rex 2489  df-v 2773  df-dif 3167  df-un 3169  df-in 3171  df-ss 3178  df-nul 3460  df-pw 3617  df-sn 3638  df-pr 3639  df-uni 3850  df-int 3885  df-tr 4142  df-iord 4412  df-on 4414  df-suc 4417  df-iom 4638

This theorem is referenced by:  frec2uzf1od  10549  nnti  15862