Metamath Proof Explorer


Theorem bj-iminvval2

Description: Value of the functionalized inverse image. (Contributed by BJ, 23-May-2024)

Ref Expression
Hypotheses bj-iminvval2.exa ⊢ ( 𝜑 → 𝐴 ∈ 𝑈 )
bj-iminvval2.exb ⊢ ( 𝜑 → 𝐵 ∈ 𝑉 )
bj-iminvval2.arg ⊢ ( 𝜑 → 𝑅 ⊆ ( 𝐴 × 𝐵 ) )
Assertion bj-iminvval2 ( 𝜑 → ( ( 𝐴 𝒫* 𝐵 ) ‘ 𝑅 ) = { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( ( 𝑥 ⊆ 𝐴 ∧ 𝑦 ⊆ 𝐵 ) ∧ 𝑥 = ( ◡ 𝑅 “ 𝑦 ) ) } )

Proof

Step Hyp Ref Expression
1 bj-iminvval2.exa ⊢ ( 𝜑 → 𝐴 ∈ 𝑈 )
2 bj-iminvval2.exb ⊢ ( 𝜑 → 𝐵 ∈ 𝑉 )
3 bj-iminvval2.arg ⊢ ( 𝜑 → 𝑅 ⊆ ( 𝐴 × 𝐵 ) )
4 1 2 bj-iminvval ⊢ ( 𝜑 → ( 𝐴 𝒫* 𝐵 ) = ( 𝑟 ∈ 𝒫 ( 𝐴 × 𝐵 ) ↦ { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( ( 𝑥 ⊆ 𝐴 ∧ 𝑦 ⊆ 𝐵 ) ∧ 𝑥 = ( ◡ 𝑟 “ 𝑦 ) ) } ) )
5 simpr ⊢ ( ( 𝜑 ∧ 𝑟 = 𝑅 ) → 𝑟 = 𝑅 )
6 5 cnveqd ⊢ ( ( 𝜑 ∧ 𝑟 = 𝑅 ) → ◡ 𝑟 = ◡ 𝑅 )
7 6 imaeq1d ⊢ ( ( 𝜑 ∧ 𝑟 = 𝑅 ) → ( ◡ 𝑟 “ 𝑦 ) = ( ◡ 𝑅 “ 𝑦 ) )
8 7 eqeq2d ⊢ ( ( 𝜑 ∧ 𝑟 = 𝑅 ) → ( 𝑥 = ( ◡ 𝑟 “ 𝑦 ) ↔ 𝑥 = ( ◡ 𝑅 “ 𝑦 ) ) )
9 8 anbi2d ⊢ ( ( 𝜑 ∧ 𝑟 = 𝑅 ) → ( ( ( 𝑥 ⊆ 𝐴 ∧ 𝑦 ⊆ 𝐵 ) ∧ 𝑥 = ( ◡ 𝑟 “ 𝑦 ) ) ↔ ( ( 𝑥 ⊆ 𝐴 ∧ 𝑦 ⊆ 𝐵 ) ∧ 𝑥 = ( ◡ 𝑅 “ 𝑦 ) ) ) )
10 9 opabbidv ⊢ ( ( 𝜑 ∧ 𝑟 = 𝑅 ) → { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( ( 𝑥 ⊆ 𝐴 ∧ 𝑦 ⊆ 𝐵 ) ∧ 𝑥 = ( ◡ 𝑟 “ 𝑦 ) ) } = { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( ( 𝑥 ⊆ 𝐴 ∧ 𝑦 ⊆ 𝐵 ) ∧ 𝑥 = ( ◡ 𝑅 “ 𝑦 ) ) } )
11 1 2 xpexd ⊢ ( 𝜑 → ( 𝐴 × 𝐵 ) ∈ V )
12 11 3 sselpwd ⊢ ( 𝜑 → 𝑅 ∈ 𝒫 ( 𝐴 × 𝐵 ) )
13 1 2 bj-imdirval2lem ⊢ ( 𝜑 → { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( ( 𝑥 ⊆ 𝐴 ∧ 𝑦 ⊆ 𝐵 ) ∧ 𝑥 = ( ◡ 𝑅 “ 𝑦 ) ) } ∈ V )
14 4 10 12 13 fvmptd ⊢ ( 𝜑 → ( ( 𝐴 𝒫* 𝐵 ) ‘ 𝑅 ) = { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( ( 𝑥 ⊆ 𝐴 ∧ 𝑦 ⊆ 𝐵 ) ∧ 𝑥 = ( ◡ 𝑅 “ 𝑦 ) ) } )