Metamath Proof Explorer


Theorem 1elunit

Description: One is an element of the closed unit interval. (Contributed by Scott Fenton, 11-Jun-2013)

Ref Expression
Assertion 1elunit 1 ∈ ( 0 [,] 1 )

Proof

Step Hyp Ref Expression
1 1re 1 ∈ ℝ
2 0le1 0 ≤ 1
3 1le1 1 ≤ 1
4 elicc01 ( 1 ∈ ( 0 [,] 1 ) ↔ ( 1 ∈ ℝ ∧ 0 ≤ 1 ∧ 1 ≤ 1 ) )
5 1 2 3 4 mpbir3an 1 ∈ ( 0 [,] 1 )