Description: A member of an open interval of reals is a real. (Contributed by Glauco Siliprandi, 26-Jun-2021)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | elioored.1 | ⊢ ( 𝜑 → 𝐴 ∈ ( 𝐵 (,) 𝐶 ) ) | |
| Assertion | elioored | ⊢ ( 𝜑 → 𝐴 ∈ ℝ ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | elioored.1 | ⊢ ( 𝜑 → 𝐴 ∈ ( 𝐵 (,) 𝐶 ) ) | |
| 2 | elioore | ⊢ ( 𝐴 ∈ ( 𝐵 (,) 𝐶 ) → 𝐴 ∈ ℝ ) | |
| 3 | 1 2 | syl | ⊢ ( 𝜑 → 𝐴 ∈ ℝ ) |