Metamath Proof Explorer


Theorem ioogtlbd

Description: An element of a closed interval is greater than its lower bound. (Contributed by Glauco Siliprandi, 26-Jun-2021)

Ref Expression
Hypotheses ioogtlbd.1 ⊢ φ → A ∈ ℝ *
ioogtlbd.2 ⊢ φ → B ∈ ℝ *
ioogtlbd.3 ⊢ φ → C ∈ A B
Assertion ioogtlbd ⊢ φ → A < C

Proof

Step Hyp Ref Expression
1 ioogtlbd.1 ⊢ φ → A ∈ ℝ *
2 ioogtlbd.2 ⊢ φ → B ∈ ℝ *
3 ioogtlbd.3 ⊢ φ → C ∈ A B
4 ioogtlb ⊢ A ∈ ℝ * ∧ B ∈ ℝ * ∧ C ∈ A B → A < C
5 1 2 3 4 syl3anc ⊢ φ → A < C