Metamath Proof Explorer


Definition df-ii

Description: Define the unit interval with the Euclidean topology. (Contributed by Jeff Madsen, 2-Sep-2009) (Revised by Mario Carneiro, 3-Sep-2015)

Ref Expression
Assertion df-ii II = ( MetOpen ‘ ( ( abs ∘ − ) ↾ ( ( 0 [,] 1 ) × ( 0 [,] 1 ) ) ) )

Detailed syntax breakdown

Step Hyp Ref Expression
0 cii ⊢ II
1 cmopn ⊢ MetOpen
2 cabs ⊢ abs
3 cmin ⊢ −
4 2 3 ccom ⊢ ( abs ∘ − )
5 cc0 ⊢ 0
6 cicc ⊢ [,]
7 c1 ⊢ 1
8 5 7 6 co ⊢ ( 0 [,] 1 )
9 8 8 cxp ⊢ ( ( 0 [,] 1 ) × ( 0 [,] 1 ) )
10 4 9 cres ⊢ ( ( abs ∘ − ) ↾ ( ( 0 [,] 1 ) × ( 0 [,] 1 ) ) )
11 10 1 cfv ⊢ ( MetOpen ‘ ( ( abs ∘ − ) ↾ ( ( 0 [,] 1 ) × ( 0 [,] 1 ) ) ) )
12 0 11 wceq ⊢ II = ( MetOpen ‘ ( ( abs ∘ − ) ↾ ( ( 0 [,] 1 ) × ( 0 [,] 1 ) ) ) )