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Theorem iunfopab 5205
Description: Two ways to express a function as a class of ordered pairs. (The proof was shortened by Andrew Salmon, 17-Sep-2011.) (Unnecessary distinct variable restrictions were removed by David Abernethy, 19-Sep-2011.) (Contributed by set.mm contributors, 19-Dec-2008.)
Hypothesis
Ref Expression
iunfopab.1 ⊢ B ∈ V
Assertion
Ref Expression
iunfopab ⊢ ∪x ∈ A {⟨x, B⟩} = {⟨x, y⟩ ∣ (x ∈ A ∧ y = B)}
Distinct variable groups:   y,A   y,B   x,y
Allowed substitution hints:   A(x)   B(x)

Proof of Theorem iunfopab
Dummy variable z is distinct from all other variables.
StepHypRef Expression
1 df-rex 2621 . . . 4 ⊢ (∃x ∈ A z ∈ {⟨x, B⟩} ↔ ∃x(x ∈ A ∧ z ∈ {⟨x, B⟩}))
2 vex 2863 . . . . . . . 8 ⊢ z ∈ V
32elsnc 3757 . . . . . . 7 ⊢ (z ∈ {⟨x, B⟩} ↔ z = ⟨x, B⟩)
43anbi2i 675 . . . . . 6 ⊢ ((x ∈ A ∧ z ∈ {⟨x, B⟩}) ↔ (x ∈ A ∧ z = ⟨x, B⟩))
5 iunfopab.1 . . . . . . 7 ⊢ B ∈ V
6 opeq2 4580 . . . . . . . . 9 ⊢ (y = B → ⟨x, y⟩ = ⟨x, B⟩)
76eqeq2d 2364 . . . . . . . 8 ⊢ (y = B → (z = ⟨x, y⟩ ↔ z = ⟨x, B⟩))
87anbi2d 684 . . . . . . 7 ⊢ (y = B → ((x ∈ A ∧ z = ⟨x, y⟩) ↔ (x ∈ A ∧ z = ⟨x, B⟩)))
95, 8ceqsexv 2895 . . . . . 6 ⊢ (∃y(y = B ∧ (x ∈ A ∧ z = ⟨x, y⟩)) ↔ (x ∈ A ∧ z = ⟨x, B⟩))
10 an13 774 . . . . . . 7 ⊢ ((y = B ∧ (x ∈ A ∧ z = ⟨x, y⟩)) ↔ (z = ⟨x, y⟩ ∧ (x ∈ A ∧ y = B)))
1110exbii 1582 . . . . . 6 ⊢ (∃y(y = B ∧ (x ∈ A ∧ z = ⟨x, y⟩)) ↔ ∃y(z = ⟨x, y⟩ ∧ (x ∈ A ∧ y = B)))
124, 9, 113bitr2i 264 . . . . 5 ⊢ ((x ∈ A ∧ z ∈ {⟨x, B⟩}) ↔ ∃y(z = ⟨x, y⟩ ∧ (x ∈ A ∧ y = B)))
1312exbii 1582 . . . 4 ⊢ (∃x(x ∈ A ∧ z ∈ {⟨x, B⟩}) ↔ ∃x∃y(z = ⟨x, y⟩ ∧ (x ∈ A ∧ y = B)))
141, 13bitri 240 . . 3 ⊢ (∃x ∈ A z ∈ {⟨x, B⟩} ↔ ∃x∃y(z = ⟨x, y⟩ ∧ (x ∈ A ∧ y = B)))
1514abbii 2466 . 2 ⊢ {z ∣ ∃x ∈ A z ∈ {⟨x, B⟩}} = {z ∣ ∃x∃y(z = ⟨x, y⟩ ∧ (x ∈ A ∧ y = B))}
16 df-iun 3972 . 2 ⊢ ∪x ∈ A {⟨x, B⟩} = {z ∣ ∃x ∈ A z ∈ {⟨x, B⟩}}
17 df-opab 4624 . 2 ⊢ {⟨x, y⟩ ∣ (x ∈ A ∧ y = B)} = {z ∣ ∃x∃y(z = ⟨x, y⟩ ∧ (x ∈ A ∧ y = B))}
1815, 16, 173eqtr4i 2383 1 ⊢ ∪x ∈ A {⟨x, B⟩} = {⟨x, y⟩ ∣ (x ∈ A ∧ y = B)}
Colors of variables:    wff setvar class
This proof depends on syntax axioms:   ∧ wa 358  ∃wex 1541   = wceq 1642   ∈ wcel 1710  {cab 2339  ∃wrex 2616  Vcvv 2860  {csn 3738  ∪ciun 3970  ⟨cop 4562  {copab 4623
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-xp 4080  ax-cnv 4081  ax-1c 4082  ax-sset 4083  ax-si 4084  ax-ins2 4085  ax-ins3 4086  ax-typlower 4087  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-ral 2620  df-rex 2621  df-v 2862  df-sbc 3048  df-nin 3212  df-compl 3213  df-in 3214  df-un 3215  df-dif 3216  df-symdif 3217  df-ss 3260  df-nul 3552  df-if 3664  df-pw 3725  df-sn 3742  df-pr 3743  df-uni 3893  df-int 3928  df-iun 3972  df-opk 4059  df-1c 4137  df-pw1 4138  df-uni1 4139  df-xpk 4186  df-cnvk 4187  df-ins2k 4188  df-ins3k 4189  df-imak 4190  df-cok 4191  df-p6 4192  df-sik 4193  df-ssetk 4194  df-imagek 4195  df-idk 4196  df-addc 4379  df-nnc 4380  df-phi 4566  df-op 4567  df-opab 4624
This theorem is used by: (None)
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