Metamath Proof Explorer


Theorem infxrcld

Description: The infimum of an arbitrary set of extended reals is an extended real. (Contributed by Glauco Siliprandi, 26-Jun-2021)

Ref Expression
Hypothesis infxrcld.1 ⊢ φ → A ⊆ ℝ *
Assertion infxrcld ⊢ φ → inf A ℝ * < ∈ ℝ *

Proof

Step Hyp Ref Expression
1 infxrcld.1 ⊢ φ → A ⊆ ℝ *
2 infxrcl ⊢ A ⊆ ℝ * → inf A ℝ * < ∈ ℝ *
3 1 2 syl ⊢ φ → inf A ℝ * < ∈ ℝ *