Metamath Proof Explorer


Theorem rrexttps

Description: An extension of RR is a topological space. (Contributed by Thierry Arnoux, 7-Sep-2018)

Ref Expression
Assertion rrexttps ( 𝑅 ∈ ℝExt β†’ 𝑅 ∈ TopSp )

Proof

Step Hyp Ref Expression
1 rrextnrg ⊒ ( 𝑅 ∈ ℝExt β†’ 𝑅 ∈ NrmRing )
2 nrgngp ⊒ ( 𝑅 ∈ NrmRing β†’ 𝑅 ∈ NrmGrp )
3 ngpxms ⊒ ( 𝑅 ∈ NrmGrp β†’ 𝑅 ∈ ∞MetSp )
4 1 2 3 3syl ⊒ ( 𝑅 ∈ ℝExt β†’ 𝑅 ∈ ∞MetSp )
5 xmstps ⊒ ( 𝑅 ∈ ∞MetSp β†’ 𝑅 ∈ TopSp )
6 4 5 syl ⊒ ( 𝑅 ∈ ℝExt β†’ 𝑅 ∈ TopSp )