Metamath Proof Explorer


Theorem ioosshoi

Description: A n-dimensional open interval is a subset of the half-open interval with the same bounds. (Contributed by Glauco Siliprandi, 8-Apr-2021)

Ref Expression
Assertion ioosshoi
|- X_ k e. X ( A (,) B ) C_ X_ k e. X ( A [,) B )

Proof

Step Hyp Ref Expression
1 nftru
 |-  F/ k T.
2 ioossico
 |-  ( A (,) B ) C_ ( A [,) B )
3 2 a1i
 |-  ( ( T. /\ k e. X ) -> ( A (,) B ) C_ ( A [,) B ) )
4 1 3 ixpssixp
 |-  ( T. -> X_ k e. X ( A (,) B ) C_ X_ k e. X ( A [,) B ) )
5 4 mptru
 |-  X_ k e. X ( A (,) B ) C_ X_ k e. X ( A [,) B )