Description: suprcld without ax-mulcom , proven trivially from sn-sup3d . (Contributed by SN, 29-Jun-2025)
Ref | Expression | ||
---|---|---|---|
Hypotheses | sn-sup3d.1 | ⊢ ( 𝜑 → 𝐴 ⊆ ℝ ) | |
sn-sup3d.2 | ⊢ ( 𝜑 → 𝐴 ≠ ∅ ) | ||
sn-sup3d.3 | ⊢ ( 𝜑 → ∃ 𝑥 ∈ ℝ ∀ 𝑦 ∈ 𝐴 𝑦 ≤ 𝑥 ) | ||
Assertion | sn-suprcld | ⊢ ( 𝜑 → sup ( 𝐴 , ℝ , < ) ∈ ℝ ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | sn-sup3d.1 | ⊢ ( 𝜑 → 𝐴 ⊆ ℝ ) | |
2 | sn-sup3d.2 | ⊢ ( 𝜑 → 𝐴 ≠ ∅ ) | |
3 | sn-sup3d.3 | ⊢ ( 𝜑 → ∃ 𝑥 ∈ ℝ ∀ 𝑦 ∈ 𝐴 𝑦 ≤ 𝑥 ) | |
4 | ltso | ⊢ < Or ℝ | |
5 | 4 | a1i | ⊢ ( 𝜑 → < Or ℝ ) |
6 | 1 2 3 | sn-sup3d | ⊢ ( 𝜑 → ∃ 𝑥 ∈ ℝ ( ∀ 𝑦 ∈ 𝐴 ¬ 𝑥 < 𝑦 ∧ ∀ 𝑦 ∈ ℝ ( 𝑦 < 𝑥 → ∃ 𝑧 ∈ 𝐴 𝑦 < 𝑧 ) ) ) |
7 | 5 6 | supcl | ⊢ ( 𝜑 → sup ( 𝐴 , ℝ , < ) ∈ ℝ ) |