Metamath Proof Explorer


Theorem fsovfd

Description: The operator, ( A O B ) , which maps between maps from one base set to subsets of the second to maps from the second base set to subsets of the first for base sets, A and B , gives a function between two sets of functions. (Contributed by RP, 27-Apr-2021)

Ref Expression
Hypotheses fsovd.fs 𝑂 = ( 𝑎 ∈ V , 𝑏 ∈ V ↦ ( 𝑓 ∈ ( 𝒫 𝑏m 𝑎 ) ↦ ( 𝑦𝑏 ↦ { 𝑥𝑎𝑦 ∈ ( 𝑓𝑥 ) } ) ) )
fsovd.a ( 𝜑𝐴𝑉 )
fsovd.b ( 𝜑𝐵𝑊 )
fsovfvd.g 𝐺 = ( 𝐴 𝑂 𝐵 )
Assertion fsovfd ( 𝜑𝐺 : ( 𝒫 𝐵m 𝐴 ) ⟶ ( 𝒫 𝐴m 𝐵 ) )

Proof

Step Hyp Ref Expression
1 fsovd.fs 𝑂 = ( 𝑎 ∈ V , 𝑏 ∈ V ↦ ( 𝑓 ∈ ( 𝒫 𝑏m 𝑎 ) ↦ ( 𝑦𝑏 ↦ { 𝑥𝑎𝑦 ∈ ( 𝑓𝑥 ) } ) ) )
2 fsovd.a ( 𝜑𝐴𝑉 )
3 fsovd.b ( 𝜑𝐵𝑊 )
4 fsovfvd.g 𝐺 = ( 𝐴 𝑂 𝐵 )
5 1 2 3 fsovd ( 𝜑 → ( 𝐴 𝑂 𝐵 ) = ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ↦ ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) ) )
6 4 5 syl5eq ( 𝜑𝐺 = ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ↦ ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) ) )
7 ssrab2 { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ⊆ 𝐴
8 7 a1i ( 𝜑 → { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ⊆ 𝐴 )
9 2 8 sselpwd ( 𝜑 → { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ∈ 𝒫 𝐴 )
10 9 adantr ( ( 𝜑𝑦𝐵 ) → { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ∈ 𝒫 𝐴 )
11 10 fmpttd ( 𝜑 → ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) : 𝐵 ⟶ 𝒫 𝐴 )
12 2 pwexd ( 𝜑 → 𝒫 𝐴 ∈ V )
13 12 3 elmapd ( 𝜑 → ( ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) ∈ ( 𝒫 𝐴m 𝐵 ) ↔ ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) : 𝐵 ⟶ 𝒫 𝐴 ) )
14 11 13 mpbird ( 𝜑 → ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) ∈ ( 𝒫 𝐴m 𝐵 ) )
15 14 adantr ( ( 𝜑𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ) → ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) ∈ ( 𝒫 𝐴m 𝐵 ) )
16 6 15 fmpt3d ( 𝜑𝐺 : ( 𝒫 𝐵m 𝐴 ) ⟶ ( 𝒫 𝐴m 𝐵 ) )