Metamath Proof Explorer


Theorem metustrel

Description: Elements of the filter base generated by the metric D are relations. (Contributed by Thierry Arnoux, 28-Nov-2017) (Revised by Thierry Arnoux, 11-Feb-2018)

Ref Expression
Hypothesis metust.1 ⊢ 𝐹 = ran ( 𝑎 ∈ ℝ+ ↦ ( ◡ 𝐷 “ ( 0 [,) 𝑎 ) ) )
Assertion metustrel ( ( 𝐷 ∈ ( PsMet ‘ 𝑋 ) ∧ 𝐴 ∈ 𝐹 ) → Rel 𝐴 )

Proof

Step Hyp Ref Expression
1 metust.1 ⊢ 𝐹 = ran ( 𝑎 ∈ ℝ+ ↦ ( ◡ 𝐷 “ ( 0 [,) 𝑎 ) ) )
2 1 metustss ⊢ ( ( 𝐷 ∈ ( PsMet ‘ 𝑋 ) ∧ 𝐴 ∈ 𝐹 ) → 𝐴 ⊆ ( 𝑋 × 𝑋 ) )
3 xpss ⊢ ( 𝑋 × 𝑋 ) ⊆ ( V × V )
4 2 3 sstrdi ⊢ ( ( 𝐷 ∈ ( PsMet ‘ 𝑋 ) ∧ 𝐴 ∈ 𝐹 ) → 𝐴 ⊆ ( V × V ) )
5 df-rel ⊢ ( Rel 𝐴 ↔ 𝐴 ⊆ ( V × V ) )
6 4 5 sylibr ⊢ ( ( 𝐷 ∈ ( PsMet ‘ 𝑋 ) ∧ 𝐴 ∈ 𝐹 ) → Rel 𝐴 )