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* ) |
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* ) |