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 ) ) ) ) |
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 ) ) ) ) |