Database
SUPPLEMENTARY MATERIAL (USERS' MATHBOXES)
Mathbox for Glauco Siliprandi
Real intervals
iocleubd
Metamath Proof Explorer
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 )