Theorem prneimg2 4835

Description: Two pairs are not equal if their counterparts are not equal. (Contributed by AV, 5-Sep-2025.)

Assertion

Ref	Expression
prneimg2	⊢ (((𝐴 ∈ 𝑈 ∧ 𝐵 ∈ 𝑉) ∧ (𝐶 ∈ 𝑋 ∧ 𝐷 ∈ 𝑌)) → ({𝐴, 𝐵} ≠ {𝐶, 𝐷} ↔ ((𝐴 ≠ 𝐶 ∨ 𝐵 ≠ 𝐷) ∧ (𝐴 ≠ 𝐷 ∨ 𝐵 ≠ 𝐶))))

Proof of Theorem prneimg2

Step	Hyp	Ref	Expression
1		preq12bg 4833	. . 3 ⊢ (((𝐴 ∈ 𝑈 ∧ 𝐵 ∈ 𝑉) ∧ (𝐶 ∈ 𝑋 ∧ 𝐷 ∈ 𝑌)) → ({𝐴, 𝐵} = {𝐶, 𝐷} ↔ ((𝐴 = 𝐶 ∧ 𝐵 = 𝐷) ∨ (𝐴 = 𝐷 ∧ 𝐵 = 𝐶))))
2	1	necon3abid 2967	. 2 ⊢ (((𝐴 ∈ 𝑈 ∧ 𝐵 ∈ 𝑉) ∧ (𝐶 ∈ 𝑋 ∧ 𝐷 ∈ 𝑌)) → ({𝐴, 𝐵} ≠ {𝐶, 𝐷} ↔ ¬ ((𝐴 = 𝐶 ∧ 𝐵 = 𝐷) ∨ (𝐴 = 𝐷 ∧ 𝐵 = 𝐶))))
3		ioran 985	. . 3 ⊢ (¬ ((𝐴 = 𝐶 ∧ 𝐵 = 𝐷) ∨ (𝐴 = 𝐷 ∧ 𝐵 = 𝐶)) ↔ (¬ (𝐴 = 𝐶 ∧ 𝐵 = 𝐷) ∧ ¬ (𝐴 = 𝐷 ∧ 𝐵 = 𝐶)))
4		ianor 983	. . . . 5 ⊢ (¬ (𝐴 = 𝐶 ∧ 𝐵 = 𝐷) ↔ (¬ 𝐴 = 𝐶 ∨ ¬ 𝐵 = 𝐷))
5		df-ne 2932	. . . . . 6 ⊢ (𝐴 ≠ 𝐶 ↔ ¬ 𝐴 = 𝐶)
6		df-ne 2932	. . . . . 6 ⊢ (𝐵 ≠ 𝐷 ↔ ¬ 𝐵 = 𝐷)
7	5, 6	orbi12i 914	. . . . 5 ⊢ ((𝐴 ≠ 𝐶 ∨ 𝐵 ≠ 𝐷) ↔ (¬ 𝐴 = 𝐶 ∨ ¬ 𝐵 = 𝐷))
8	4, 7	bitr4i 278	. . . 4 ⊢ (¬ (𝐴 = 𝐶 ∧ 𝐵 = 𝐷) ↔ (𝐴 ≠ 𝐶 ∨ 𝐵 ≠ 𝐷))
9		ianor 983	. . . . 5 ⊢ (¬ (𝐴 = 𝐷 ∧ 𝐵 = 𝐶) ↔ (¬ 𝐴 = 𝐷 ∨ ¬ 𝐵 = 𝐶))
10		df-ne 2932	. . . . . 6 ⊢ (𝐴 ≠ 𝐷 ↔ ¬ 𝐴 = 𝐷)
11		df-ne 2932	. . . . . 6 ⊢ (𝐵 ≠ 𝐶 ↔ ¬ 𝐵 = 𝐶)
12	10, 11	orbi12i 914	. . . . 5 ⊢ ((𝐴 ≠ 𝐷 ∨ 𝐵 ≠ 𝐶) ↔ (¬ 𝐴 = 𝐷 ∨ ¬ 𝐵 = 𝐶))
13	9, 12	bitr4i 278	. . . 4 ⊢ (¬ (𝐴 = 𝐷 ∧ 𝐵 = 𝐶) ↔ (𝐴 ≠ 𝐷 ∨ 𝐵 ≠ 𝐶))
14	8, 13	anbi12i 628	. . 3 ⊢ ((¬ (𝐴 = 𝐶 ∧ 𝐵 = 𝐷) ∧ ¬ (𝐴 = 𝐷 ∧ 𝐵 = 𝐶)) ↔ ((𝐴 ≠ 𝐶 ∨ 𝐵 ≠ 𝐷) ∧ (𝐴 ≠ 𝐷 ∨ 𝐵 ≠ 𝐶)))
15	3, 14	bitri 275	. 2 ⊢ (¬ ((𝐴 = 𝐶 ∧ 𝐵 = 𝐷) ∨ (𝐴 = 𝐷 ∧ 𝐵 = 𝐶)) ↔ ((𝐴 ≠ 𝐶 ∨ 𝐵 ≠ 𝐷) ∧ (𝐴 ≠ 𝐷 ∨ 𝐵 ≠ 𝐶)))
16	2, 15	bitrdi 287	1 ⊢ (((𝐴 ∈ 𝑈 ∧ 𝐵 ∈ 𝑉) ∧ (𝐶 ∈ 𝑋 ∧ 𝐷 ∈ 𝑌)) → ({𝐴, 𝐵} ≠ {𝐶, 𝐷} ↔ ((𝐴 ≠ 𝐶 ∨ 𝐵 ≠ 𝐷) ∧ (𝐴 ≠ 𝐷 ∨ 𝐵 ≠ 𝐶))))

Syntax hints:  ¬ wn 3   → wi 4   ↔ wb 206   ∧ wa 395   ∨ wo 847   = wceq 1539   ∈ wcel 2107   ≠ wne 2931  {cpr 4608

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1794  ax-4 1808  ax-5 1909  ax-6 1966  ax-7 2006  ax-8 2109  ax-9 2117  ax-ext 2706

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-3an 1088  df-tru 1542  df-ex 1779  df-sb 2064  df-clab 2713  df-cleq 2726  df-clel 2808  df-ne 2932  df-v 3465  df-un 3936  df-sn 4607  df-pr 4609

This theorem is referenced by:  gpg5nbgrvtx03starlem1  47997  gpg5nbgrvtx03starlem2  47998  gpg5nbgrvtx03starlem3  47999  gpg5nbgrvtx13starlem1  48000  gpg5nbgrvtx13starlem2  48001  gpg5nbgrvtx13starlem3  48002