Metamath Proof Explorer


Definition df-tx

Description: Define the binary topological product, which is homeomorphic to the general topological product over a two element set, but is more convenient to use. (Contributed by Jeff Madsen, 2-Sep-2009)

Ref Expression
Assertion df-tx ×t = ( 𝑟 ∈ V , 𝑠 ∈ V ↦ ( topGen ‘ ran ( 𝑥 ∈ 𝑟 , 𝑦 ∈ 𝑠 ↦ ( 𝑥 × 𝑦 ) ) ) )

Detailed syntax breakdown

Step Hyp Ref Expression
0 ctx ⊢ ×t
1 vr ⊢ 𝑟
2 cvv ⊢ V
3 vs ⊢ 𝑠
4 ctg ⊢ topGen
5 vx ⊢ 𝑥
6 1 cv ⊢ 𝑟
7 vy ⊢ 𝑦
8 3 cv ⊢ 𝑠
9 5 cv ⊢ 𝑥
10 7 cv ⊢ 𝑦
11 9 10 cxp ⊢ ( 𝑥 × 𝑦 )
12 5 7 6 8 11 cmpo ⊢ ( 𝑥 ∈ 𝑟 , 𝑦 ∈ 𝑠 ↦ ( 𝑥 × 𝑦 ) )
13 12 crn ⊢ ran ( 𝑥 ∈ 𝑟 , 𝑦 ∈ 𝑠 ↦ ( 𝑥 × 𝑦 ) )
14 13 4 cfv ⊢ ( topGen ‘ ran ( 𝑥 ∈ 𝑟 , 𝑦 ∈ 𝑠 ↦ ( 𝑥 × 𝑦 ) ) )
15 1 3 2 2 14 cmpo ⊢ ( 𝑟 ∈ V , 𝑠 ∈ V ↦ ( topGen ‘ ran ( 𝑥 ∈ 𝑟 , 𝑦 ∈ 𝑠 ↦ ( 𝑥 × 𝑦 ) ) ) )
16 0 15 wceq ⊢ ×t = ( 𝑟 ∈ V , 𝑠 ∈ V ↦ ( topGen ‘ ran ( 𝑥 ∈ 𝑟 , 𝑦 ∈ 𝑠 ↦ ( 𝑥 × 𝑦 ) ) ) )