Theorem oppfrcl2 50042

Description: If an opposite functor of a class is a functor, then the two components of the original class must be sets. (Contributed by Zhi Wang, 14-Nov-2025.)

Hypotheses

Ref	Expression
oppfrcl.1	⊢ (𝜑 → 𝐺 ∈ 𝑅)
oppfrcl.2	⊢ Rel 𝑅
oppfrcl.3	⊢ 𝐺 = ( oppFunc ‘𝐹)
oppfrcl2.4	⊢ (𝜑 → 𝐹 = ⟨𝐴, 𝐵⟩)

Assertion

Ref	Expression
oppfrcl2	⊢ (𝜑 → (𝐴 ∈ V ∧ 𝐵 ∈ V))

Proof of Theorem oppfrcl2

Step	Hyp	Ref	Expression
1		oppfrcl2.4	. . . 4 ⊢ (𝜑 → 𝐹 = ⟨𝐴, 𝐵⟩)
2		oppfrcl.1	. . . . 5 ⊢ (𝜑 → 𝐺 ∈ 𝑅)
3		oppfrcl.2	. . . . 5 ⊢ Rel 𝑅
4		oppfrcl.3	. . . . 5 ⊢ 𝐺 = ( oppFunc ‘𝐹)
5	2, 3, 4	oppfrcl 50041	. . . 4 ⊢ (𝜑 → 𝐹 ∈ (V × V))
6	1, 5	eqeltrrd 2863	. . 3 ⊢ (𝜑 → ⟨𝐴, 𝐵⟩ ∈ (V × V))
7		0nelxp 5693	. . 3 ⊢ ¬ ∅ ∈ (V × V)
8		nelne2 3055	. . 3 ⊢ ((⟨𝐴, 𝐵⟩ ∈ (V × V) ∧ ¬ ∅ ∈ (V × V)) → ⟨𝐴, 𝐵⟩ ≠ ∅)
9	6, 7, 8	sylancl 598	. 2 ⊢ (𝜑 → ⟨𝐴, 𝐵⟩ ≠ ∅)
10		opprc 4859	. . 3 ⊢ (¬ (𝐴 ∈ V ∧ 𝐵 ∈ V) → ⟨𝐴, 𝐵⟩ = ∅)
11	10	necon1ai 2984	. 2 ⊢ (⟨𝐴, 𝐵⟩ ≠ ∅ → (𝐴 ∈ V ∧ 𝐵 ∈ V))
12	9, 11	syl 18	1 ⊢ (𝜑 → (𝐴 ∈ V ∧ 𝐵 ∈ V))

This proof depends on syntax axioms:  ¬ wn 3   → wi 4   ∧ wa 401   = wceq 1570   ∈ wcel 2145   ≠ wne 2957  Vcvv 3453  ∅c0 4282  ⟨cop 4593   × cxp 5657  Rel wrel 5664  ‘cfv 6537   oppFunc coppf 50035

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-8 2147  ax-9 2155  ax-10 2178  ax-11 2194  ax-12 2215  ax-ext 2734  ax-sep 5255  ax-nul 5267  ax-pr 5402  ax-un 7739

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-nf 1817  df-sb 2100  df-mo 2566  df-eu 2596  df-clab 2741  df-cleq 2754  df-clel 2837  df-nfc 2911  df-ne 2958  df-ral 3079  df-rex 3089  df-rab 3415  df-v 3455  df-sbc 3743  df-csb 3851  df-dif 3905  df-un 3907  df-in 3909  df-ss 3919  df-nul 4283  df-if 4486  df-sn 4588  df-pr 4590  df-op 4594  df-uni 4871  df-iun 4956  df-br 5108  df-opab 5172  df-mpt 5191  df-id 5554  df-xp 5665  df-rel 5666  df-cnv 5667  df-co 5668  df-dm 5669  df-rn 5670  df-res 5671  df-ima 5672  df-iota 6493  df-fun 6539  df-fn 6540  df-f 6541  df-fv 6545  df-oprab 7420  df-mpo 7421  df-1st 7989  df-2nd 7990  df-oppf 50036

This theorem is used by:  oppfrcl3  50043  oppf1st2nd  50044