Description: The function appearing in xpsval is a bijection from the cartesian product to the indexed cartesian product indexed on the pair 2o = { (/) , 1o } . (Contributed by Mario Carneiro, 24-Jan-2015)
Ref | Expression | ||
---|---|---|---|
Hypothesis | xpsff1o.f | ⊢ 𝐹 = ( 𝑥 ∈ 𝐴 , 𝑦 ∈ 𝐵 ↦ { 〈 ∅ , 𝑥 〉 , 〈 1o , 𝑦 〉 } ) | |
Assertion | xpsff1o2 | ⊢ 𝐹 : ( 𝐴 × 𝐵 ) –1-1-onto→ ran 𝐹 |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | xpsff1o.f | ⊢ 𝐹 = ( 𝑥 ∈ 𝐴 , 𝑦 ∈ 𝐵 ↦ { 〈 ∅ , 𝑥 〉 , 〈 1o , 𝑦 〉 } ) | |
2 | 1 | xpsff1o | ⊢ 𝐹 : ( 𝐴 × 𝐵 ) –1-1-onto→ X 𝑘 ∈ 2o if ( 𝑘 = ∅ , 𝐴 , 𝐵 ) |
3 | f1of1 | ⊢ ( 𝐹 : ( 𝐴 × 𝐵 ) –1-1-onto→ X 𝑘 ∈ 2o if ( 𝑘 = ∅ , 𝐴 , 𝐵 ) → 𝐹 : ( 𝐴 × 𝐵 ) –1-1→ X 𝑘 ∈ 2o if ( 𝑘 = ∅ , 𝐴 , 𝐵 ) ) | |
4 | f1f1orn | ⊢ ( 𝐹 : ( 𝐴 × 𝐵 ) –1-1→ X 𝑘 ∈ 2o if ( 𝑘 = ∅ , 𝐴 , 𝐵 ) → 𝐹 : ( 𝐴 × 𝐵 ) –1-1-onto→ ran 𝐹 ) | |
5 | 2 3 4 | mp2b | ⊢ 𝐹 : ( 𝐴 × 𝐵 ) –1-1-onto→ ran 𝐹 |