This is an inofficial mirror of http://metamath.tirix.org for personal testing of a visualizer extension only.

Metamath Proof Explorer


Theorem metxmet

Description: A metric is an extended metric. (Contributed by Mario Carneiro, 20-Aug-2015)

Ref Expression
Assertion metxmet D Met X D ∞Met X

Proof

Step Hyp Ref Expression
1 ismet2 D Met X D ∞Met X D : X × X
2 1 simplbi D Met X D ∞Met X