Metamath Proof Explorer


Theorem fsovrfovd

Description: The operator which gives a 1-to-1 a mapping to a subset and a reverse mapping from elements can be composed from the operator which gives a 1-to-1 mapping between relations and functions to subsets and the converse operator. (Contributed by RP, 15-May-2021)

Ref Expression
Hypotheses fsovd.fs 𝑂 = ( 𝑎 ∈ V , 𝑏 ∈ V ↦ ( 𝑓 ∈ ( 𝒫 𝑏m 𝑎 ) ↦ ( 𝑦𝑏 ↦ { 𝑥𝑎𝑦 ∈ ( 𝑓𝑥 ) } ) ) )
fsovd.a ( 𝜑𝐴𝑉 )
fsovd.b ( 𝜑𝐵𝑊 )
fsovd.rf 𝑅 = ( 𝑎 ∈ V , 𝑏 ∈ V ↦ ( 𝑟 ∈ 𝒫 ( 𝑎 × 𝑏 ) ↦ ( 𝑢𝑎 ↦ { 𝑣𝑏𝑢 𝑟 𝑣 } ) ) )
fsovd.cnv 𝐶 = ( 𝑎 ∈ V , 𝑏 ∈ V ↦ ( 𝑠 ∈ 𝒫 ( 𝑎 × 𝑏 ) ↦ 𝑠 ) )
Assertion fsovrfovd ( 𝜑 → ( 𝐴 𝑂 𝐵 ) = ( ( 𝐵 𝑅 𝐴 ) ∘ ( ( 𝐴 𝐶 𝐵 ) ∘ ( 𝐴 𝑅 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 fsovd.rf 𝑅 = ( 𝑎 ∈ V , 𝑏 ∈ V ↦ ( 𝑟 ∈ 𝒫 ( 𝑎 × 𝑏 ) ↦ ( 𝑢𝑎 ↦ { 𝑣𝑏𝑢 𝑟 𝑣 } ) ) )
5 fsovd.cnv 𝐶 = ( 𝑎 ∈ V , 𝑏 ∈ V ↦ ( 𝑠 ∈ 𝒫 ( 𝑎 × 𝑏 ) ↦ 𝑠 ) )
6 3 2 xpexd ( 𝜑 → ( 𝐵 × 𝐴 ) ∈ V )
7 6 adantr ( ( 𝜑𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ) → ( 𝐵 × 𝐴 ) ∈ V )
8 elmapi ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) → 𝑓 : 𝐴 ⟶ 𝒫 𝐵 )
9 8 ffvelrnda ( ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ∧ 𝑢𝐴 ) → ( 𝑓𝑢 ) ∈ 𝒫 𝐵 )
10 9 elpwid ( ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ∧ 𝑢𝐴 ) → ( 𝑓𝑢 ) ⊆ 𝐵 )
11 10 sseld ( ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ∧ 𝑢𝐴 ) → ( 𝑣 ∈ ( 𝑓𝑢 ) → 𝑣𝐵 ) )
12 11 impancom ( ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ∧ 𝑣 ∈ ( 𝑓𝑢 ) ) → ( 𝑢𝐴𝑣𝐵 ) )
13 12 pm4.71d ( ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ∧ 𝑣 ∈ ( 𝑓𝑢 ) ) → ( 𝑢𝐴 ↔ ( 𝑢𝐴𝑣𝐵 ) ) )
14 13 ex ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) → ( 𝑣 ∈ ( 𝑓𝑢 ) → ( 𝑢𝐴 ↔ ( 𝑢𝐴𝑣𝐵 ) ) ) )
15 14 pm5.32rd ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) → ( ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) ↔ ( ( 𝑢𝐴𝑣𝐵 ) ∧ 𝑣 ∈ ( 𝑓𝑢 ) ) ) )
16 ancom ( ( 𝑢𝐴𝑣𝐵 ) ↔ ( 𝑣𝐵𝑢𝐴 ) )
17 16 anbi1i ( ( ( 𝑢𝐴𝑣𝐵 ) ∧ 𝑣 ∈ ( 𝑓𝑢 ) ) ↔ ( ( 𝑣𝐵𝑢𝐴 ) ∧ 𝑣 ∈ ( 𝑓𝑢 ) ) )
18 15 17 bitrdi ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) → ( ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) ↔ ( ( 𝑣𝐵𝑢𝐴 ) ∧ 𝑣 ∈ ( 𝑓𝑢 ) ) ) )
19 18 opabbidv ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) → { ⟨ 𝑣 , 𝑢 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } = { ⟨ 𝑣 , 𝑢 ⟩ ∣ ( ( 𝑣𝐵𝑢𝐴 ) ∧ 𝑣 ∈ ( 𝑓𝑢 ) ) } )
20 opabssxp { ⟨ 𝑣 , 𝑢 ⟩ ∣ ( ( 𝑣𝐵𝑢𝐴 ) ∧ 𝑣 ∈ ( 𝑓𝑢 ) ) } ⊆ ( 𝐵 × 𝐴 )
21 19 20 eqsstrdi ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) → { ⟨ 𝑣 , 𝑢 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } ⊆ ( 𝐵 × 𝐴 ) )
22 21 adantl ( ( 𝜑𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ) → { ⟨ 𝑣 , 𝑢 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } ⊆ ( 𝐵 × 𝐴 ) )
23 7 22 sselpwd ( ( 𝜑𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ) → { ⟨ 𝑣 , 𝑢 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } ∈ 𝒫 ( 𝐵 × 𝐴 ) )
24 eqidd ( 𝜑 → ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ↦ { ⟨ 𝑣 , 𝑢 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } ) = ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ↦ { ⟨ 𝑣 , 𝑢 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } ) )
25 4 3 2 rfovd ( 𝜑 → ( 𝐵 𝑅 𝐴 ) = ( 𝑟 ∈ 𝒫 ( 𝐵 × 𝐴 ) ↦ ( 𝑢𝐵 ↦ { 𝑣𝐴𝑢 𝑟 𝑣 } ) ) )
26 breq ( 𝑟 = 𝑡 → ( 𝑢 𝑟 𝑣𝑢 𝑡 𝑣 ) )
27 26 rabbidv ( 𝑟 = 𝑡 → { 𝑣𝐴𝑢 𝑟 𝑣 } = { 𝑣𝐴𝑢 𝑡 𝑣 } )
28 27 mpteq2dv ( 𝑟 = 𝑡 → ( 𝑢𝐵 ↦ { 𝑣𝐴𝑢 𝑟 𝑣 } ) = ( 𝑢𝐵 ↦ { 𝑣𝐴𝑢 𝑡 𝑣 } ) )
29 breq1 ( 𝑢 = 𝑐 → ( 𝑢 𝑡 𝑣𝑐 𝑡 𝑣 ) )
30 29 rabbidv ( 𝑢 = 𝑐 → { 𝑣𝐴𝑢 𝑡 𝑣 } = { 𝑣𝐴𝑐 𝑡 𝑣 } )
31 breq2 ( 𝑣 = 𝑑 → ( 𝑐 𝑡 𝑣𝑐 𝑡 𝑑 ) )
32 31 cbvrabv { 𝑣𝐴𝑐 𝑡 𝑣 } = { 𝑑𝐴𝑐 𝑡 𝑑 }
33 30 32 eqtrdi ( 𝑢 = 𝑐 → { 𝑣𝐴𝑢 𝑡 𝑣 } = { 𝑑𝐴𝑐 𝑡 𝑑 } )
34 33 cbvmptv ( 𝑢𝐵 ↦ { 𝑣𝐴𝑢 𝑡 𝑣 } ) = ( 𝑐𝐵 ↦ { 𝑑𝐴𝑐 𝑡 𝑑 } )
35 28 34 eqtrdi ( 𝑟 = 𝑡 → ( 𝑢𝐵 ↦ { 𝑣𝐴𝑢 𝑟 𝑣 } ) = ( 𝑐𝐵 ↦ { 𝑑𝐴𝑐 𝑡 𝑑 } ) )
36 35 cbvmptv ( 𝑟 ∈ 𝒫 ( 𝐵 × 𝐴 ) ↦ ( 𝑢𝐵 ↦ { 𝑣𝐴𝑢 𝑟 𝑣 } ) ) = ( 𝑡 ∈ 𝒫 ( 𝐵 × 𝐴 ) ↦ ( 𝑐𝐵 ↦ { 𝑑𝐴𝑐 𝑡 𝑑 } ) )
37 25 36 eqtrdi ( 𝜑 → ( 𝐵 𝑅 𝐴 ) = ( 𝑡 ∈ 𝒫 ( 𝐵 × 𝐴 ) ↦ ( 𝑐𝐵 ↦ { 𝑑𝐴𝑐 𝑡 𝑑 } ) ) )
38 breq ( 𝑡 = { ⟨ 𝑣 , 𝑢 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } → ( 𝑐 𝑡 𝑑𝑐 { ⟨ 𝑣 , 𝑢 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } 𝑑 ) )
39 df-br ( 𝑐 { ⟨ 𝑣 , 𝑢 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } 𝑑 ↔ ⟨ 𝑐 , 𝑑 ⟩ ∈ { ⟨ 𝑣 , 𝑢 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } )
40 vex 𝑐 ∈ V
41 vex 𝑑 ∈ V
42 eleq1w ( 𝑣 = 𝑐 → ( 𝑣 ∈ ( 𝑓𝑢 ) ↔ 𝑐 ∈ ( 𝑓𝑢 ) ) )
43 42 anbi2d ( 𝑣 = 𝑐 → ( ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) ↔ ( 𝑢𝐴𝑐 ∈ ( 𝑓𝑢 ) ) ) )
44 eleq1w ( 𝑢 = 𝑑 → ( 𝑢𝐴𝑑𝐴 ) )
45 fveq2 ( 𝑢 = 𝑑 → ( 𝑓𝑢 ) = ( 𝑓𝑑 ) )
46 45 eleq2d ( 𝑢 = 𝑑 → ( 𝑐 ∈ ( 𝑓𝑢 ) ↔ 𝑐 ∈ ( 𝑓𝑑 ) ) )
47 44 46 anbi12d ( 𝑢 = 𝑑 → ( ( 𝑢𝐴𝑐 ∈ ( 𝑓𝑢 ) ) ↔ ( 𝑑𝐴𝑐 ∈ ( 𝑓𝑑 ) ) ) )
48 40 41 43 47 opelopab ( ⟨ 𝑐 , 𝑑 ⟩ ∈ { ⟨ 𝑣 , 𝑢 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } ↔ ( 𝑑𝐴𝑐 ∈ ( 𝑓𝑑 ) ) )
49 39 48 bitri ( 𝑐 { ⟨ 𝑣 , 𝑢 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } 𝑑 ↔ ( 𝑑𝐴𝑐 ∈ ( 𝑓𝑑 ) ) )
50 38 49 bitrdi ( 𝑡 = { ⟨ 𝑣 , 𝑢 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } → ( 𝑐 𝑡 𝑑 ↔ ( 𝑑𝐴𝑐 ∈ ( 𝑓𝑑 ) ) ) )
51 50 rabbidv ( 𝑡 = { ⟨ 𝑣 , 𝑢 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } → { 𝑑𝐴𝑐 𝑡 𝑑 } = { 𝑑𝐴 ∣ ( 𝑑𝐴𝑐 ∈ ( 𝑓𝑑 ) ) } )
52 51 mpteq2dv ( 𝑡 = { ⟨ 𝑣 , 𝑢 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } → ( 𝑐𝐵 ↦ { 𝑑𝐴𝑐 𝑡 𝑑 } ) = ( 𝑐𝐵 ↦ { 𝑑𝐴 ∣ ( 𝑑𝐴𝑐 ∈ ( 𝑓𝑑 ) ) } ) )
53 ibar ( 𝑑𝐴 → ( 𝑐 ∈ ( 𝑓𝑑 ) ↔ ( 𝑑𝐴𝑐 ∈ ( 𝑓𝑑 ) ) ) )
54 53 bicomd ( 𝑑𝐴 → ( ( 𝑑𝐴𝑐 ∈ ( 𝑓𝑑 ) ) ↔ 𝑐 ∈ ( 𝑓𝑑 ) ) )
55 54 rabbiia { 𝑑𝐴 ∣ ( 𝑑𝐴𝑐 ∈ ( 𝑓𝑑 ) ) } = { 𝑑𝐴𝑐 ∈ ( 𝑓𝑑 ) }
56 fveq2 ( 𝑑 = 𝑥 → ( 𝑓𝑑 ) = ( 𝑓𝑥 ) )
57 56 eleq2d ( 𝑑 = 𝑥 → ( 𝑐 ∈ ( 𝑓𝑑 ) ↔ 𝑐 ∈ ( 𝑓𝑥 ) ) )
58 57 cbvrabv { 𝑑𝐴𝑐 ∈ ( 𝑓𝑑 ) } = { 𝑥𝐴𝑐 ∈ ( 𝑓𝑥 ) }
59 55 58 eqtri { 𝑑𝐴 ∣ ( 𝑑𝐴𝑐 ∈ ( 𝑓𝑑 ) ) } = { 𝑥𝐴𝑐 ∈ ( 𝑓𝑥 ) }
60 59 mpteq2i ( 𝑐𝐵 ↦ { 𝑑𝐴 ∣ ( 𝑑𝐴𝑐 ∈ ( 𝑓𝑑 ) ) } ) = ( 𝑐𝐵 ↦ { 𝑥𝐴𝑐 ∈ ( 𝑓𝑥 ) } )
61 eleq1w ( 𝑐 = 𝑦 → ( 𝑐 ∈ ( 𝑓𝑥 ) ↔ 𝑦 ∈ ( 𝑓𝑥 ) ) )
62 61 rabbidv ( 𝑐 = 𝑦 → { 𝑥𝐴𝑐 ∈ ( 𝑓𝑥 ) } = { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } )
63 62 cbvmptv ( 𝑐𝐵 ↦ { 𝑥𝐴𝑐 ∈ ( 𝑓𝑥 ) } ) = ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } )
64 60 63 eqtri ( 𝑐𝐵 ↦ { 𝑑𝐴 ∣ ( 𝑑𝐴𝑐 ∈ ( 𝑓𝑑 ) ) } ) = ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } )
65 52 64 eqtrdi ( 𝑡 = { ⟨ 𝑣 , 𝑢 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } → ( 𝑐𝐵 ↦ { 𝑑𝐴𝑐 𝑡 𝑑 } ) = ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) )
66 23 24 37 65 fmptco ( 𝜑 → ( ( 𝐵 𝑅 𝐴 ) ∘ ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ↦ { ⟨ 𝑣 , 𝑢 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } ) ) = ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ↦ ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) ) )
67 2 3 xpexd ( 𝜑 → ( 𝐴 × 𝐵 ) ∈ V )
68 67 adantr ( ( 𝜑𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ) → ( 𝐴 × 𝐵 ) ∈ V )
69 15 opabbidv ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) → { ⟨ 𝑢 , 𝑣 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } = { ⟨ 𝑢 , 𝑣 ⟩ ∣ ( ( 𝑢𝐴𝑣𝐵 ) ∧ 𝑣 ∈ ( 𝑓𝑢 ) ) } )
70 opabssxp { ⟨ 𝑢 , 𝑣 ⟩ ∣ ( ( 𝑢𝐴𝑣𝐵 ) ∧ 𝑣 ∈ ( 𝑓𝑢 ) ) } ⊆ ( 𝐴 × 𝐵 )
71 69 70 eqsstrdi ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) → { ⟨ 𝑢 , 𝑣 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } ⊆ ( 𝐴 × 𝐵 ) )
72 71 adantl ( ( 𝜑𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ) → { ⟨ 𝑢 , 𝑣 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } ⊆ ( 𝐴 × 𝐵 ) )
73 68 72 sselpwd ( ( 𝜑𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ) → { ⟨ 𝑢 , 𝑣 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } ∈ 𝒫 ( 𝐴 × 𝐵 ) )
74 eqid ( 𝐴 𝑅 𝐵 ) = ( 𝐴 𝑅 𝐵 )
75 4 2 3 74 rfovcnvd ( 𝜑 ( 𝐴 𝑅 𝐵 ) = ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ↦ { ⟨ 𝑢 , 𝑣 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } ) )
76 5 a1i ( 𝜑𝐶 = ( 𝑎 ∈ V , 𝑏 ∈ V ↦ ( 𝑠 ∈ 𝒫 ( 𝑎 × 𝑏 ) ↦ 𝑠 ) ) )
77 xpeq12 ( ( 𝑎 = 𝐴𝑏 = 𝐵 ) → ( 𝑎 × 𝑏 ) = ( 𝐴 × 𝐵 ) )
78 77 pweqd ( ( 𝑎 = 𝐴𝑏 = 𝐵 ) → 𝒫 ( 𝑎 × 𝑏 ) = 𝒫 ( 𝐴 × 𝐵 ) )
79 78 mpteq1d ( ( 𝑎 = 𝐴𝑏 = 𝐵 ) → ( 𝑠 ∈ 𝒫 ( 𝑎 × 𝑏 ) ↦ 𝑠 ) = ( 𝑠 ∈ 𝒫 ( 𝐴 × 𝐵 ) ↦ 𝑠 ) )
80 79 adantl ( ( 𝜑 ∧ ( 𝑎 = 𝐴𝑏 = 𝐵 ) ) → ( 𝑠 ∈ 𝒫 ( 𝑎 × 𝑏 ) ↦ 𝑠 ) = ( 𝑠 ∈ 𝒫 ( 𝐴 × 𝐵 ) ↦ 𝑠 ) )
81 2 elexd ( 𝜑𝐴 ∈ V )
82 3 elexd ( 𝜑𝐵 ∈ V )
83 pwexg ( ( 𝐴 × 𝐵 ) ∈ V → 𝒫 ( 𝐴 × 𝐵 ) ∈ V )
84 mptexg ( 𝒫 ( 𝐴 × 𝐵 ) ∈ V → ( 𝑠 ∈ 𝒫 ( 𝐴 × 𝐵 ) ↦ 𝑠 ) ∈ V )
85 67 83 84 3syl ( 𝜑 → ( 𝑠 ∈ 𝒫 ( 𝐴 × 𝐵 ) ↦ 𝑠 ) ∈ V )
86 76 80 81 82 85 ovmpod ( 𝜑 → ( 𝐴 𝐶 𝐵 ) = ( 𝑠 ∈ 𝒫 ( 𝐴 × 𝐵 ) ↦ 𝑠 ) )
87 cnveq ( 𝑠 = { ⟨ 𝑢 , 𝑣 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } → 𝑠 = { ⟨ 𝑢 , 𝑣 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } )
88 cnvopab { ⟨ 𝑢 , 𝑣 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } = { ⟨ 𝑣 , 𝑢 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) }
89 87 88 eqtrdi ( 𝑠 = { ⟨ 𝑢 , 𝑣 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } → 𝑠 = { ⟨ 𝑣 , 𝑢 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } )
90 73 75 86 89 fmptco ( 𝜑 → ( ( 𝐴 𝐶 𝐵 ) ∘ ( 𝐴 𝑅 𝐵 ) ) = ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ↦ { ⟨ 𝑣 , 𝑢 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } ) )
91 90 coeq2d ( 𝜑 → ( ( 𝐵 𝑅 𝐴 ) ∘ ( ( 𝐴 𝐶 𝐵 ) ∘ ( 𝐴 𝑅 𝐵 ) ) ) = ( ( 𝐵 𝑅 𝐴 ) ∘ ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ↦ { ⟨ 𝑣 , 𝑢 ⟩ ∣ ( 𝑢𝐴𝑣 ∈ ( 𝑓𝑢 ) ) } ) ) )
92 1 2 3 fsovd ( 𝜑 → ( 𝐴 𝑂 𝐵 ) = ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ↦ ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) ) )
93 66 91 92 3eqtr4rd ( 𝜑 → ( 𝐴 𝑂 𝐵 ) = ( ( 𝐵 𝑅 𝐴 ) ∘ ( ( 𝐴 𝐶 𝐵 ) ∘ ( 𝐴 𝑅 𝐵 ) ) ) )