Metamath Proof Explorer


Theorem nfimad

Description: Deduction version of bound-variable hypothesis builder nfima . (Contributed by FL, 15-Dec-2006) (Revised by Mario Carneiro, 15-Oct-2016)

Ref Expression
Hypotheses nfimad.2 ( 𝜑 𝑥 𝐴 )
nfimad.3 ( 𝜑 𝑥 𝐵 )
Assertion nfimad ( 𝜑 𝑥 ( 𝐴𝐵 ) )

Proof

Step Hyp Ref Expression
1 nfimad.2 ( 𝜑 𝑥 𝐴 )
2 nfimad.3 ( 𝜑 𝑥 𝐵 )
3 nfaba1 𝑥 { 𝑧 ∣ ∀ 𝑥 𝑧𝐴 }
4 nfaba1 𝑥 { 𝑧 ∣ ∀ 𝑥 𝑧𝐵 }
5 3 4 nfima 𝑥 ( { 𝑧 ∣ ∀ 𝑥 𝑧𝐴 } “ { 𝑧 ∣ ∀ 𝑥 𝑧𝐵 } )
6 nfnfc1 𝑥 𝑥 𝐴
7 nfnfc1 𝑥 𝑥 𝐵
8 6 7 nfan 𝑥 ( 𝑥 𝐴 𝑥 𝐵 )
9 abidnf ( 𝑥 𝐴 → { 𝑧 ∣ ∀ 𝑥 𝑧𝐴 } = 𝐴 )
10 9 imaeq1d ( 𝑥 𝐴 → ( { 𝑧 ∣ ∀ 𝑥 𝑧𝐴 } “ { 𝑧 ∣ ∀ 𝑥 𝑧𝐵 } ) = ( 𝐴 “ { 𝑧 ∣ ∀ 𝑥 𝑧𝐵 } ) )
11 abidnf ( 𝑥 𝐵 → { 𝑧 ∣ ∀ 𝑥 𝑧𝐵 } = 𝐵 )
12 11 imaeq2d ( 𝑥 𝐵 → ( 𝐴 “ { 𝑧 ∣ ∀ 𝑥 𝑧𝐵 } ) = ( 𝐴𝐵 ) )
13 10 12 sylan9eq ( ( 𝑥 𝐴 𝑥 𝐵 ) → ( { 𝑧 ∣ ∀ 𝑥 𝑧𝐴 } “ { 𝑧 ∣ ∀ 𝑥 𝑧𝐵 } ) = ( 𝐴𝐵 ) )
14 8 13 nfceqdf ( ( 𝑥 𝐴 𝑥 𝐵 ) → ( 𝑥 ( { 𝑧 ∣ ∀ 𝑥 𝑧𝐴 } “ { 𝑧 ∣ ∀ 𝑥 𝑧𝐵 } ) ↔ 𝑥 ( 𝐴𝐵 ) ) )
15 1 2 14 syl2anc ( 𝜑 → ( 𝑥 ( { 𝑧 ∣ ∀ 𝑥 𝑧𝐴 } “ { 𝑧 ∣ ∀ 𝑥 𝑧𝐵 } ) ↔ 𝑥 ( 𝐴𝐵 ) ) )
16 5 15 mpbii ( 𝜑 𝑥 ( 𝐴𝐵 ) )