Metamath Proof Explorer


Theorem metpsmet

Description: A metric is a pseudometric. (Contributed by Glauco Siliprandi, 8-Apr-2021)

Ref Expression
Assertion metpsmet D Met X D PsMet X

Proof

Step Hyp Ref Expression
1 metxmet D Met X D ∞Met X
2 xmetpsmet D ∞Met X D PsMet X
3 1 2 syl D Met X D PsMet X