Metamath Proof Explorer


Theorem suprleubrd

Description: Natural deduction form of specialized suprleub . (Contributed by Stanislas Polu, 9-Mar-2020)

Ref Expression
Hypotheses suprleubrd.1 ⊢ ( 𝜑 → 𝐴 ⊆ ℝ )
suprleubrd.2 ⊢ ( 𝜑 → 𝐴 ≠ ∅ )
suprleubrd.3 ⊢ ( 𝜑 → ∃ 𝑥 ∈ ℝ ∀ 𝑦 ∈ 𝐴 𝑦 ≤ 𝑥 )
suprleubrd.4 ⊢ ( 𝜑 → 𝐵 ∈ ℝ )
suprleubrd.5 ⊢ ( 𝜑 → ∀ 𝑧 ∈ 𝐴 𝑧 ≤ 𝐵 )
Assertion suprleubrd ( 𝜑 → sup ( 𝐴 , ℝ , < ) ≤ 𝐵 )

Proof

Step Hyp Ref Expression
1 suprleubrd.1 ⊢ ( 𝜑 → 𝐴 ⊆ ℝ )
2 suprleubrd.2 ⊢ ( 𝜑 → 𝐴 ≠ ∅ )
3 suprleubrd.3 ⊢ ( 𝜑 → ∃ 𝑥 ∈ ℝ ∀ 𝑦 ∈ 𝐴 𝑦 ≤ 𝑥 )
4 suprleubrd.4 ⊢ ( 𝜑 → 𝐵 ∈ ℝ )
5 suprleubrd.5 ⊢ ( 𝜑 → ∀ 𝑧 ∈ 𝐴 𝑧 ≤ 𝐵 )
6 suprleub ⊢ ( ( ( 𝐴 ⊆ ℝ ∧ 𝐴 ≠ ∅ ∧ ∃ 𝑥 ∈ ℝ ∀ 𝑦 ∈ 𝐴 𝑦 ≤ 𝑥 ) ∧ 𝐵 ∈ ℝ ) → ( sup ( 𝐴 , ℝ , < ) ≤ 𝐵 ↔ ∀ 𝑧 ∈ 𝐴 𝑧 ≤ 𝐵 ) )
7 1 2 3 4 6 syl31anc ⊢ ( 𝜑 → ( sup ( 𝐴 , ℝ , < ) ≤ 𝐵 ↔ ∀ 𝑧 ∈ 𝐴 𝑧 ≤ 𝐵 ) )
8 7 bicomd ⊢ ( 𝜑 → ( ∀ 𝑧 ∈ 𝐴 𝑧 ≤ 𝐵 ↔ sup ( 𝐴 , ℝ , < ) ≤ 𝐵 ) )
9 8 biimpd ⊢ ( 𝜑 → ( ∀ 𝑧 ∈ 𝐴 𝑧 ≤ 𝐵 → sup ( 𝐴 , ℝ , < ) ≤ 𝐵 ) )
10 9 imp ⊢ ( ( 𝜑 ∧ ∀ 𝑧 ∈ 𝐴 𝑧 ≤ 𝐵 ) → sup ( 𝐴 , ℝ , < ) ≤ 𝐵 )
11 5 10 mpdan ⊢ ( 𝜑 → sup ( 𝐴 , ℝ , < ) ≤ 𝐵 )