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 -1 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 -1 y
5 simpr ⊢ φ ∧ r = R → r = R
6 5 cnveqd ⊢ φ ∧ r = R → r -1 = R -1
7 6 imaeq1d ⊢ φ ∧ r = R → r -1 y = R -1 y
8 7 eqeq2d ⊢ φ ∧ r = R → x = r -1 y ↔ x = R -1 y
9 8 anbi2d ⊢ φ ∧ r = R → x ⊆ A ∧ y ⊆ B ∧ x = r -1 y ↔ x ⊆ A ∧ y ⊆ B ∧ x = R -1 y
10 9 opabbidv ⊢ φ ∧ r = R → x y | x ⊆ A ∧ y ⊆ B ∧ x = r -1 y = x y | x ⊆ A ∧ y ⊆ B ∧ x = R -1 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 -1 y ∈ V
14 4 10 12 13 fvmptd ⊢ φ → A 𝒫 * B ⁡ R = x y | x ⊆ A ∧ y ⊆ B ∧ x = R -1 y