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metpsmet
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Metamath Proof Explorer
Ascii
Unicode
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