Metamath Proof Explorer


Theorem iocleubd

Description: An element of a left-open right-closed interval is smaller than or equal to its upper bound. (Contributed by Glauco Siliprandi, 23-Oct-2021)

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

Proof

Step Hyp Ref Expression
1 iocleubd.1 ⊢ φ → A ∈ ℝ *
2 iocleubd.2 ⊢ φ → B ∈ ℝ *
3 iocleubd.3 ⊢ φ → C ∈ A B
4 iocleub ⊢ A ∈ ℝ * ∧ B ∈ ℝ * ∧ C ∈ A B → C ≤ B
5 1 2 3 4 syl3anc ⊢ φ → C ≤ B