Metamath Proof Explorer


Theorem fundcmpsurinjlem2

Description: Lemma 2 for fundcmpsurinj . (Contributed by AV, 4-Mar-2024)

Ref Expression
Hypotheses fundcmpsurinj.p ⊢ 𝑃 = { 𝑧 ∣ ∃ 𝑥 ∈ 𝐴 𝑧 = ( ◡ 𝐹 “ { ( 𝐹 ‘ 𝑥 ) } ) }
fundcmpsurinj.g ⊢ 𝐺 = ( 𝑥 ∈ 𝐴 ↦ ( ◡ 𝐹 “ { ( 𝐹 ‘ 𝑥 ) } ) )
Assertion fundcmpsurinjlem2 ( ( 𝐹 Fn 𝐴 ∧ 𝐴 ∈ 𝑉 ) → 𝐺 : 𝐴 –onto→ 𝑃 )

Proof

Step Hyp Ref Expression
1 fundcmpsurinj.p ⊢ 𝑃 = { 𝑧 ∣ ∃ 𝑥 ∈ 𝐴 𝑧 = ( ◡ 𝐹 “ { ( 𝐹 ‘ 𝑥 ) } ) }
2 fundcmpsurinj.g ⊢ 𝐺 = ( 𝑥 ∈ 𝐴 ↦ ( ◡ 𝐹 “ { ( 𝐹 ‘ 𝑥 ) } ) )
3 fnex ⊢ ( ( 𝐹 Fn 𝐴 ∧ 𝐴 ∈ 𝑉 ) → 𝐹 ∈ V )
4 cnvexg ⊢ ( 𝐹 ∈ V → ◡ 𝐹 ∈ V )
5 imaexg ⊢ ( ◡ 𝐹 ∈ V → ( ◡ 𝐹 “ { ( 𝐹 ‘ 𝑥 ) } ) ∈ V )
6 3 4 5 3syl ⊢ ( ( 𝐹 Fn 𝐴 ∧ 𝐴 ∈ 𝑉 ) → ( ◡ 𝐹 “ { ( 𝐹 ‘ 𝑥 ) } ) ∈ V )
7 6 ralrimivw ⊢ ( ( 𝐹 Fn 𝐴 ∧ 𝐴 ∈ 𝑉 ) → ∀ 𝑥 ∈ 𝐴 ( ◡ 𝐹 “ { ( 𝐹 ‘ 𝑥 ) } ) ∈ V )
8 2 fnmpt ⊢ ( ∀ 𝑥 ∈ 𝐴 ( ◡ 𝐹 “ { ( 𝐹 ‘ 𝑥 ) } ) ∈ V → 𝐺 Fn 𝐴 )
9 7 8 syl ⊢ ( ( 𝐹 Fn 𝐴 ∧ 𝐴 ∈ 𝑉 ) → 𝐺 Fn 𝐴 )
10 1 2 fundcmpsurinjlem1 ⊢ ran 𝐺 = 𝑃
11 df-fo ⊢ ( 𝐺 : 𝐴 –onto→ 𝑃 ↔ ( 𝐺 Fn 𝐴 ∧ ran 𝐺 = 𝑃 ) )
12 9 10 11 sylanblrc ⊢ ( ( 𝐹 Fn 𝐴 ∧ 𝐴 ∈ 𝑉 ) → 𝐺 : 𝐴 –onto→ 𝑃 )