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 ) ∧ 𝐴𝐹 ) → Rel 𝐴 )

Proof

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