Metamath Proof Explorer


Theorem fsovcnvlem

Description: The O operator, 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, gives a family of functions that include their own inverse. (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 )
fsovcnvlem.h 𝐻 = ( 𝐵 𝑂 𝐴 )
Assertion fsovcnvlem ( 𝜑 → ( 𝐻𝐺 ) = ( I ↾ ( 𝒫 𝐵m 𝐴 ) ) )

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 fsovcnvlem.h 𝐻 = ( 𝐵 𝑂 𝐴 )
6 ssrab2 { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ⊆ 𝐴
7 6 a1i ( 𝜑 → { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ⊆ 𝐴 )
8 2 7 sselpwd ( 𝜑 → { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ∈ 𝒫 𝐴 )
9 8 adantr ( ( 𝜑𝑦𝐵 ) → { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ∈ 𝒫 𝐴 )
10 9 fmpttd ( 𝜑 → ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) : 𝐵 ⟶ 𝒫 𝐴 )
11 2 pwexd ( 𝜑 → 𝒫 𝐴 ∈ V )
12 11 3 elmapd ( 𝜑 → ( ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) ∈ ( 𝒫 𝐴m 𝐵 ) ↔ ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) : 𝐵 ⟶ 𝒫 𝐴 ) )
13 10 12 mpbird ( 𝜑 → ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) ∈ ( 𝒫 𝐴m 𝐵 ) )
14 13 adantr ( ( 𝜑𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ) → ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) ∈ ( 𝒫 𝐴m 𝐵 ) )
15 1 2 3 fsovd ( 𝜑 → ( 𝐴 𝑂 𝐵 ) = ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ↦ ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) ) )
16 4 15 syl5eq ( 𝜑𝐺 = ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ↦ ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) ) )
17 oveq2 ( 𝑎 = 𝑑 → ( 𝒫 𝑏m 𝑎 ) = ( 𝒫 𝑏m 𝑑 ) )
18 rabeq ( 𝑎 = 𝑑 → { 𝑥𝑎𝑦 ∈ ( 𝑓𝑥 ) } = { 𝑥𝑑𝑦 ∈ ( 𝑓𝑥 ) } )
19 18 mpteq2dv ( 𝑎 = 𝑑 → ( 𝑦𝑏 ↦ { 𝑥𝑎𝑦 ∈ ( 𝑓𝑥 ) } ) = ( 𝑦𝑏 ↦ { 𝑥𝑑𝑦 ∈ ( 𝑓𝑥 ) } ) )
20 17 19 mpteq12dv ( 𝑎 = 𝑑 → ( 𝑓 ∈ ( 𝒫 𝑏m 𝑎 ) ↦ ( 𝑦𝑏 ↦ { 𝑥𝑎𝑦 ∈ ( 𝑓𝑥 ) } ) ) = ( 𝑓 ∈ ( 𝒫 𝑏m 𝑑 ) ↦ ( 𝑦𝑏 ↦ { 𝑥𝑑𝑦 ∈ ( 𝑓𝑥 ) } ) ) )
21 pweq ( 𝑏 = 𝑐 → 𝒫 𝑏 = 𝒫 𝑐 )
22 21 oveq1d ( 𝑏 = 𝑐 → ( 𝒫 𝑏m 𝑑 ) = ( 𝒫 𝑐m 𝑑 ) )
23 mpteq1 ( 𝑏 = 𝑐 → ( 𝑦𝑏 ↦ { 𝑥𝑑𝑦 ∈ ( 𝑓𝑥 ) } ) = ( 𝑦𝑐 ↦ { 𝑥𝑑𝑦 ∈ ( 𝑓𝑥 ) } ) )
24 22 23 mpteq12dv ( 𝑏 = 𝑐 → ( 𝑓 ∈ ( 𝒫 𝑏m 𝑑 ) ↦ ( 𝑦𝑏 ↦ { 𝑥𝑑𝑦 ∈ ( 𝑓𝑥 ) } ) ) = ( 𝑓 ∈ ( 𝒫 𝑐m 𝑑 ) ↦ ( 𝑦𝑐 ↦ { 𝑥𝑑𝑦 ∈ ( 𝑓𝑥 ) } ) ) )
25 20 24 cbvmpov ( 𝑎 ∈ V , 𝑏 ∈ V ↦ ( 𝑓 ∈ ( 𝒫 𝑏m 𝑎 ) ↦ ( 𝑦𝑏 ↦ { 𝑥𝑎𝑦 ∈ ( 𝑓𝑥 ) } ) ) ) = ( 𝑑 ∈ V , 𝑐 ∈ V ↦ ( 𝑓 ∈ ( 𝒫 𝑐m 𝑑 ) ↦ ( 𝑦𝑐 ↦ { 𝑥𝑑𝑦 ∈ ( 𝑓𝑥 ) } ) ) )
26 eqid V = V
27 fveq1 ( 𝑓 = 𝑔 → ( 𝑓𝑥 ) = ( 𝑔𝑥 ) )
28 27 eleq2d ( 𝑓 = 𝑔 → ( 𝑦 ∈ ( 𝑓𝑥 ) ↔ 𝑦 ∈ ( 𝑔𝑥 ) ) )
29 28 rabbidv ( 𝑓 = 𝑔 → { 𝑥𝑑𝑦 ∈ ( 𝑓𝑥 ) } = { 𝑥𝑑𝑦 ∈ ( 𝑔𝑥 ) } )
30 29 mpteq2dv ( 𝑓 = 𝑔 → ( 𝑦𝑐 ↦ { 𝑥𝑑𝑦 ∈ ( 𝑓𝑥 ) } ) = ( 𝑦𝑐 ↦ { 𝑥𝑑𝑦 ∈ ( 𝑔𝑥 ) } ) )
31 30 cbvmptv ( 𝑓 ∈ ( 𝒫 𝑐m 𝑑 ) ↦ ( 𝑦𝑐 ↦ { 𝑥𝑑𝑦 ∈ ( 𝑓𝑥 ) } ) ) = ( 𝑔 ∈ ( 𝒫 𝑐m 𝑑 ) ↦ ( 𝑦𝑐 ↦ { 𝑥𝑑𝑦 ∈ ( 𝑔𝑥 ) } ) )
32 eleq1w ( 𝑦 = 𝑢 → ( 𝑦 ∈ ( 𝑔𝑥 ) ↔ 𝑢 ∈ ( 𝑔𝑥 ) ) )
33 32 rabbidv ( 𝑦 = 𝑢 → { 𝑥𝑑𝑦 ∈ ( 𝑔𝑥 ) } = { 𝑥𝑑𝑢 ∈ ( 𝑔𝑥 ) } )
34 33 cbvmptv ( 𝑦𝑐 ↦ { 𝑥𝑑𝑦 ∈ ( 𝑔𝑥 ) } ) = ( 𝑢𝑐 ↦ { 𝑥𝑑𝑢 ∈ ( 𝑔𝑥 ) } )
35 fveq2 ( 𝑥 = 𝑣 → ( 𝑔𝑥 ) = ( 𝑔𝑣 ) )
36 35 eleq2d ( 𝑥 = 𝑣 → ( 𝑢 ∈ ( 𝑔𝑥 ) ↔ 𝑢 ∈ ( 𝑔𝑣 ) ) )
37 36 cbvrabv { 𝑥𝑑𝑢 ∈ ( 𝑔𝑥 ) } = { 𝑣𝑑𝑢 ∈ ( 𝑔𝑣 ) }
38 37 mpteq2i ( 𝑢𝑐 ↦ { 𝑥𝑑𝑢 ∈ ( 𝑔𝑥 ) } ) = ( 𝑢𝑐 ↦ { 𝑣𝑑𝑢 ∈ ( 𝑔𝑣 ) } )
39 34 38 eqtri ( 𝑦𝑐 ↦ { 𝑥𝑑𝑦 ∈ ( 𝑔𝑥 ) } ) = ( 𝑢𝑐 ↦ { 𝑣𝑑𝑢 ∈ ( 𝑔𝑣 ) } )
40 39 mpteq2i ( 𝑔 ∈ ( 𝒫 𝑐m 𝑑 ) ↦ ( 𝑦𝑐 ↦ { 𝑥𝑑𝑦 ∈ ( 𝑔𝑥 ) } ) ) = ( 𝑔 ∈ ( 𝒫 𝑐m 𝑑 ) ↦ ( 𝑢𝑐 ↦ { 𝑣𝑑𝑢 ∈ ( 𝑔𝑣 ) } ) )
41 31 40 eqtri ( 𝑓 ∈ ( 𝒫 𝑐m 𝑑 ) ↦ ( 𝑦𝑐 ↦ { 𝑥𝑑𝑦 ∈ ( 𝑓𝑥 ) } ) ) = ( 𝑔 ∈ ( 𝒫 𝑐m 𝑑 ) ↦ ( 𝑢𝑐 ↦ { 𝑣𝑑𝑢 ∈ ( 𝑔𝑣 ) } ) )
42 26 26 41 mpoeq123i ( 𝑑 ∈ V , 𝑐 ∈ V ↦ ( 𝑓 ∈ ( 𝒫 𝑐m 𝑑 ) ↦ ( 𝑦𝑐 ↦ { 𝑥𝑑𝑦 ∈ ( 𝑓𝑥 ) } ) ) ) = ( 𝑑 ∈ V , 𝑐 ∈ V ↦ ( 𝑔 ∈ ( 𝒫 𝑐m 𝑑 ) ↦ ( 𝑢𝑐 ↦ { 𝑣𝑑𝑢 ∈ ( 𝑔𝑣 ) } ) ) )
43 1 25 42 3eqtri 𝑂 = ( 𝑑 ∈ V , 𝑐 ∈ V ↦ ( 𝑔 ∈ ( 𝒫 𝑐m 𝑑 ) ↦ ( 𝑢𝑐 ↦ { 𝑣𝑑𝑢 ∈ ( 𝑔𝑣 ) } ) ) )
44 43 3 2 fsovd ( 𝜑 → ( 𝐵 𝑂 𝐴 ) = ( 𝑔 ∈ ( 𝒫 𝐴m 𝐵 ) ↦ ( 𝑢𝐴 ↦ { 𝑣𝐵𝑢 ∈ ( 𝑔𝑣 ) } ) ) )
45 5 44 syl5eq ( 𝜑𝐻 = ( 𝑔 ∈ ( 𝒫 𝐴m 𝐵 ) ↦ ( 𝑢𝐴 ↦ { 𝑣𝐵𝑢 ∈ ( 𝑔𝑣 ) } ) ) )
46 fveq1 ( 𝑔 = ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) → ( 𝑔𝑣 ) = ( ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) ‘ 𝑣 ) )
47 46 eleq2d ( 𝑔 = ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) → ( 𝑢 ∈ ( 𝑔𝑣 ) ↔ 𝑢 ∈ ( ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) ‘ 𝑣 ) ) )
48 47 rabbidv ( 𝑔 = ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) → { 𝑣𝐵𝑢 ∈ ( 𝑔𝑣 ) } = { 𝑣𝐵𝑢 ∈ ( ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) ‘ 𝑣 ) } )
49 48 mpteq2dv ( 𝑔 = ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) → ( 𝑢𝐴 ↦ { 𝑣𝐵𝑢 ∈ ( 𝑔𝑣 ) } ) = ( 𝑢𝐴 ↦ { 𝑣𝐵𝑢 ∈ ( ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) ‘ 𝑣 ) } ) )
50 14 16 45 49 fmptco ( 𝜑 → ( 𝐻𝐺 ) = ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ↦ ( 𝑢𝐴 ↦ { 𝑣𝐵𝑢 ∈ ( ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) ‘ 𝑣 ) } ) ) )
51 eqidd ( ( ( 𝜑𝑢𝐴 ) ∧ 𝑣𝐵 ) → ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) = ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) )
52 eleq1w ( 𝑦 = 𝑣 → ( 𝑦 ∈ ( 𝑓𝑥 ) ↔ 𝑣 ∈ ( 𝑓𝑥 ) ) )
53 52 rabbidv ( 𝑦 = 𝑣 → { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } = { 𝑥𝐴𝑣 ∈ ( 𝑓𝑥 ) } )
54 53 adantl ( ( ( ( 𝜑𝑢𝐴 ) ∧ 𝑣𝐵 ) ∧ 𝑦 = 𝑣 ) → { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } = { 𝑥𝐴𝑣 ∈ ( 𝑓𝑥 ) } )
55 simpr ( ( ( 𝜑𝑢𝐴 ) ∧ 𝑣𝐵 ) → 𝑣𝐵 )
56 rabexg ( 𝐴𝑉 → { 𝑥𝐴𝑣 ∈ ( 𝑓𝑥 ) } ∈ V )
57 2 56 syl ( 𝜑 → { 𝑥𝐴𝑣 ∈ ( 𝑓𝑥 ) } ∈ V )
58 57 ad2antrr ( ( ( 𝜑𝑢𝐴 ) ∧ 𝑣𝐵 ) → { 𝑥𝐴𝑣 ∈ ( 𝑓𝑥 ) } ∈ V )
59 51 54 55 58 fvmptd ( ( ( 𝜑𝑢𝐴 ) ∧ 𝑣𝐵 ) → ( ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) ‘ 𝑣 ) = { 𝑥𝐴𝑣 ∈ ( 𝑓𝑥 ) } )
60 59 eleq2d ( ( ( 𝜑𝑢𝐴 ) ∧ 𝑣𝐵 ) → ( 𝑢 ∈ ( ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) ‘ 𝑣 ) ↔ 𝑢 ∈ { 𝑥𝐴𝑣 ∈ ( 𝑓𝑥 ) } ) )
61 fveq2 ( 𝑥 = 𝑢 → ( 𝑓𝑥 ) = ( 𝑓𝑢 ) )
62 61 eleq2d ( 𝑥 = 𝑢 → ( 𝑣 ∈ ( 𝑓𝑥 ) ↔ 𝑣 ∈ ( 𝑓𝑢 ) ) )
63 62 elrab3 ( 𝑢𝐴 → ( 𝑢 ∈ { 𝑥𝐴𝑣 ∈ ( 𝑓𝑥 ) } ↔ 𝑣 ∈ ( 𝑓𝑢 ) ) )
64 63 ad2antlr ( ( ( 𝜑𝑢𝐴 ) ∧ 𝑣𝐵 ) → ( 𝑢 ∈ { 𝑥𝐴𝑣 ∈ ( 𝑓𝑥 ) } ↔ 𝑣 ∈ ( 𝑓𝑢 ) ) )
65 60 64 bitrd ( ( ( 𝜑𝑢𝐴 ) ∧ 𝑣𝐵 ) → ( 𝑢 ∈ ( ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) ‘ 𝑣 ) ↔ 𝑣 ∈ ( 𝑓𝑢 ) ) )
66 65 rabbidva ( ( 𝜑𝑢𝐴 ) → { 𝑣𝐵𝑢 ∈ ( ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) ‘ 𝑣 ) } = { 𝑣𝐵𝑣 ∈ ( 𝑓𝑢 ) } )
67 66 adantlr ( ( ( 𝜑𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ) ∧ 𝑢𝐴 ) → { 𝑣𝐵𝑢 ∈ ( ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) ‘ 𝑣 ) } = { 𝑣𝐵𝑣 ∈ ( 𝑓𝑢 ) } )
68 elmapi ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) → 𝑓 : 𝐴 ⟶ 𝒫 𝐵 )
69 68 ad2antlr ( ( ( 𝜑𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ) ∧ 𝑢𝐴 ) → 𝑓 : 𝐴 ⟶ 𝒫 𝐵 )
70 simpr ( ( ( 𝜑𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ) ∧ 𝑢𝐴 ) → 𝑢𝐴 )
71 69 70 ffvelrnd ( ( ( 𝜑𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ) ∧ 𝑢𝐴 ) → ( 𝑓𝑢 ) ∈ 𝒫 𝐵 )
72 71 elpwid ( ( ( 𝜑𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ) ∧ 𝑢𝐴 ) → ( 𝑓𝑢 ) ⊆ 𝐵 )
73 sseqin2 ( ( 𝑓𝑢 ) ⊆ 𝐵 ↔ ( 𝐵 ∩ ( 𝑓𝑢 ) ) = ( 𝑓𝑢 ) )
74 72 73 sylib ( ( ( 𝜑𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ) ∧ 𝑢𝐴 ) → ( 𝐵 ∩ ( 𝑓𝑢 ) ) = ( 𝑓𝑢 ) )
75 dfin5 ( 𝐵 ∩ ( 𝑓𝑢 ) ) = { 𝑣𝐵𝑣 ∈ ( 𝑓𝑢 ) }
76 74 75 eqtr3di ( ( ( 𝜑𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ) ∧ 𝑢𝐴 ) → ( 𝑓𝑢 ) = { 𝑣𝐵𝑣 ∈ ( 𝑓𝑢 ) } )
77 67 76 eqtr4d ( ( ( 𝜑𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ) ∧ 𝑢𝐴 ) → { 𝑣𝐵𝑢 ∈ ( ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) ‘ 𝑣 ) } = ( 𝑓𝑢 ) )
78 77 mpteq2dva ( ( 𝜑𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ) → ( 𝑢𝐴 ↦ { 𝑣𝐵𝑢 ∈ ( ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) ‘ 𝑣 ) } ) = ( 𝑢𝐴 ↦ ( 𝑓𝑢 ) ) )
79 68 feqmptd ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) → 𝑓 = ( 𝑢𝐴 ↦ ( 𝑓𝑢 ) ) )
80 79 adantl ( ( 𝜑𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ) → 𝑓 = ( 𝑢𝐴 ↦ ( 𝑓𝑢 ) ) )
81 78 80 eqtr4d ( ( 𝜑𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ) → ( 𝑢𝐴 ↦ { 𝑣𝐵𝑢 ∈ ( ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) ‘ 𝑣 ) } ) = 𝑓 )
82 81 mpteq2dva ( 𝜑 → ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ↦ ( 𝑢𝐴 ↦ { 𝑣𝐵𝑢 ∈ ( ( 𝑦𝐵 ↦ { 𝑥𝐴𝑦 ∈ ( 𝑓𝑥 ) } ) ‘ 𝑣 ) } ) ) = ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ↦ 𝑓 ) )
83 mptresid ( I ↾ ( 𝒫 𝐵m 𝐴 ) ) = ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ↦ 𝑓 )
84 83 eqcomi ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ↦ 𝑓 ) = ( I ↾ ( 𝒫 𝐵m 𝐴 ) )
85 84 a1i ( 𝜑 → ( 𝑓 ∈ ( 𝒫 𝐵m 𝐴 ) ↦ 𝑓 ) = ( I ↾ ( 𝒫 𝐵m 𝐴 ) ) )
86 50 82 85 3eqtrd ( 𝜑 → ( 𝐻𝐺 ) = ( I ↾ ( 𝒫 𝐵m 𝐴 ) ) )