Metamath Proof Explorer


Theorem suprleubrd

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

Ref Expression
Hypotheses suprleubrd.1 ( 𝜑𝐴 ⊆ ℝ )
suprleubrd.2 ( 𝜑𝐴 ≠ ∅ )
suprleubrd.3 ( 𝜑 → ∃ 𝑥 ∈ ℝ ∀ 𝑦𝐴 𝑦𝑥 )
suprleubrd.4 ( 𝜑𝐵 ∈ ℝ )
suprleubrd.5 ( 𝜑 → ∀ 𝑧𝐴 𝑧𝐵 )
Assertion suprleubrd ( 𝜑 → sup ( 𝐴 , ℝ , < ) ≤ 𝐵 )

Proof

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