Metamath Proof Explorer


Theorem fzonel

Description: A half-open range does not contain its right endpoint. (Contributed by Stefan O'Rear, 25-Aug-2015)

Ref Expression
Assertion fzonel ⊢ ¬ B ∈ A ..^ B

Proof

Step Hyp Ref Expression
1 elfzolt2 ⊢ B ∈ A ..^ B → B < B
2 elfzoel2 ⊢ B ∈ A ..^ B → B ∈ ℤ
3 2 zred ⊢ B ∈ A ..^ B → B ∈ ℝ
4 3 ltnrd ⊢ B ∈ A ..^ B → ¬ B < B
5 1 4 pm2.65i ⊢ ¬ B ∈ A ..^ B