Theorem opkelcnvkg 4250

Description: Kuratowski ordered pair membership in a Kuratowski converse. (Contributed by SF, 12-Jan-2015.)

Assertion

Ref	Expression
opkelcnvkg	⊢ ((A ∈ V ∧ B ∈ W) → (⟪A, B⟫ ∈ ◡kC ↔ ⟪B, A⟫ ∈ C))

Proof of Theorem opkelcnvkg

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

Step	Hyp	Ref	Expression
1		df-cnvk 4187	. 2 ⊢ ◡kC = {z ∣ ∃x∃y(z = ⟪x, y⟫ ∧ ⟪y, x⟫ ∈ C)}
2		opkeq2 4061	. . 3 ⊢ (x = A → ⟪y, x⟫ = ⟪y, A⟫)
3	2	eleq1d 2419	. 2 ⊢ (x = A → (⟪y, x⟫ ∈ C ↔ ⟪y, A⟫ ∈ C))
4		opkeq1 4060	. . 3 ⊢ (y = B → ⟪y, A⟫ = ⟪B, A⟫)
5	4	eleq1d 2419	. 2 ⊢ (y = B → (⟪y, A⟫ ∈ C ↔ ⟪B, A⟫ ∈ C))
6	1, 3, 5	opkelopkabg 4246	1 ⊢ ((A ∈ V ∧ B ∈ W) → (⟪A, B⟫ ∈ ◡kC ↔ ⟪B, A⟫ ∈ C))

This proof depends on syntax axioms:   → wi 4   ↔ wb 176   ∧ wa 358   = wceq 1642   ∈ wcel 1710  ⟪copk 4058  ^◡_kccnvk 4176

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1546  ax-5 1557  ax-17 1616  ax-9 1654  ax-8 1675  ax-6 1729  ax-7 1734  ax-11 1746  ax-12 1925  ax-ext 2334  ax-nin 4079  ax-sn 4088

This proof depends on definitions:  df-bi 177  df-or 359  df-an 360  df-3an 936  df-nan 1288  df-tru 1319  df-ex 1542  df-nf 1545  df-sb 1649  df-clab 2340  df-cleq 2346  df-clel 2349  df-nfc 2479  df-ne 2519  df-v 2862  df-nin 3212  df-compl 3213  df-in 3214  df-un 3215  df-dif 3216  df-ss 3260  df-nul 3552  df-sn 3742  df-pr 3743  df-opk 4059  df-cnvk 4187

This theorem is used by:  opkelcnvk  4251  opkelcokg  4262