Metamath Proof Explorer


Theorem relfae

Description: The 'almost everywhere' builder for functions produces relations. (Contributed by Thierry Arnoux, 22-Oct-2017)

Ref Expression
Assertion relfae ⊢ R ∈ V ∧ M ∈ ⋃ ran ⁡ measures → Rel ⁡ R ~ae M

Proof

Step Hyp Ref Expression
1 relopabv ⊢ Rel ⁡ f g | f ∈ dom ⁡ R ⋃ dom ⁡ M ∧ g ∈ dom ⁡ R ⋃ dom ⁡ M ∧ x ∈ ⋃ dom ⁡ M | f ⁡ x R g ⁡ x M-ae.
2 faeval ⊢ R ∈ V ∧ M ∈ ⋃ ran ⁡ measures → R ~ae M = f g | f ∈ dom ⁡ R ⋃ dom ⁡ M ∧ g ∈ dom ⁡ R ⋃ dom ⁡ M ∧ x ∈ ⋃ dom ⁡ M | f ⁡ x R g ⁡ x M-ae.
3 2 releqd ⊢ R ∈ V ∧ M ∈ ⋃ ran ⁡ measures → Rel ⁡ R ~ae M ↔ Rel ⁡ f g | f ∈ dom ⁡ R ⋃ dom ⁡ M ∧ g ∈ dom ⁡ R ⋃ dom ⁡ M ∧ x ∈ ⋃ dom ⁡ M | f ⁡ x R g ⁡ x M-ae.
4 1 3 mpbiri ⊢ R ∈ V ∧ M ∈ ⋃ ran ⁡ measures → Rel ⁡ R ~ae M