Metamath Proof Explorer


Theorem xpsff1o2

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 = ( 𝑥𝐴 , 𝑦𝐵 ↦ { ⟨ ∅ , 𝑥 ⟩ , ⟨ 1o , 𝑦 ⟩ } )
Assertion xpsff1o2 𝐹 : ( 𝐴 × 𝐵 ) –1-1-onto→ ran 𝐹

Proof

Step Hyp Ref Expression
1 xpsff1o.f 𝐹 = ( 𝑥𝐴 , 𝑦𝐵 ↦ { ⟨ ∅ , 𝑥 ⟩ , ⟨ 1o , 𝑦 ⟩ } )
2 1 xpsff1o 𝐹 : ( 𝐴 × 𝐵 ) –1-1-ontoX 𝑘 ∈ 2o if ( 𝑘 = ∅ , 𝐴 , 𝐵 )
3 f1of1 ( 𝐹 : ( 𝐴 × 𝐵 ) –1-1-ontoX 𝑘 ∈ 2o if ( 𝑘 = ∅ , 𝐴 , 𝐵 ) → 𝐹 : ( 𝐴 × 𝐵 ) –1-1X 𝑘 ∈ 2o if ( 𝑘 = ∅ , 𝐴 , 𝐵 ) )
4 f1f1orn ( 𝐹 : ( 𝐴 × 𝐵 ) –1-1X 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