Metamath Proof Explorer


Theorem dvhb1dimN

Description: Two expressions for the 1-dimensional subspaces of vector space H, in the isomorphism B case where the 2nd vector component is zero. (Contributed by NM, 23-Feb-2014) (New usage is discouraged.)

Ref Expression
Hypotheses dvhb1dim.l = ( le ‘ 𝐾 )
dvhb1dim.h 𝐻 = ( LHyp ‘ 𝐾 )
dvhb1dim.t 𝑇 = ( ( LTrn ‘ 𝐾 ) ‘ 𝑊 )
dvhb1dim.r 𝑅 = ( ( trL ‘ 𝐾 ) ‘ 𝑊 )
dvhb1dim.e 𝐸 = ( ( TEndo ‘ 𝐾 ) ‘ 𝑊 )
dvhb1dim.o 0 = ( 𝑇 ↦ ( I ↾ 𝐵 ) )
Assertion dvhb1dimN ( ( ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) ∧ 𝐹𝑇 ) → { 𝑔 ∈ ( 𝑇 × 𝐸 ) ∣ ∃ 𝑠𝐸 𝑔 = ⟨ ( 𝑠𝐹 ) , 0 ⟩ } = { 𝑔 ∈ ( 𝑇 × 𝐸 ) ∣ ( ( 𝑅 ‘ ( 1st𝑔 ) ) ( 𝑅𝐹 ) ∧ ( 2nd𝑔 ) = 0 ) } )

Proof

Step Hyp Ref Expression
1 dvhb1dim.l = ( le ‘ 𝐾 )
2 dvhb1dim.h 𝐻 = ( LHyp ‘ 𝐾 )
3 dvhb1dim.t 𝑇 = ( ( LTrn ‘ 𝐾 ) ‘ 𝑊 )
4 dvhb1dim.r 𝑅 = ( ( trL ‘ 𝐾 ) ‘ 𝑊 )
5 dvhb1dim.e 𝐸 = ( ( TEndo ‘ 𝐾 ) ‘ 𝑊 )
6 dvhb1dim.o 0 = ( 𝑇 ↦ ( I ↾ 𝐵 ) )
7 eqop ( 𝑔 ∈ ( 𝑇 × 𝐸 ) → ( 𝑔 = ⟨ ( 𝑠𝐹 ) , 0 ⟩ ↔ ( ( 1st𝑔 ) = ( 𝑠𝐹 ) ∧ ( 2nd𝑔 ) = 0 ) ) )
8 7 adantl ( ( ( ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) ∧ 𝐹𝑇 ) ∧ 𝑔 ∈ ( 𝑇 × 𝐸 ) ) → ( 𝑔 = ⟨ ( 𝑠𝐹 ) , 0 ⟩ ↔ ( ( 1st𝑔 ) = ( 𝑠𝐹 ) ∧ ( 2nd𝑔 ) = 0 ) ) )
9 8 rexbidv ( ( ( ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) ∧ 𝐹𝑇 ) ∧ 𝑔 ∈ ( 𝑇 × 𝐸 ) ) → ( ∃ 𝑠𝐸 𝑔 = ⟨ ( 𝑠𝐹 ) , 0 ⟩ ↔ ∃ 𝑠𝐸 ( ( 1st𝑔 ) = ( 𝑠𝐹 ) ∧ ( 2nd𝑔 ) = 0 ) ) )
10 r19.41v ( ∃ 𝑠𝐸 ( ( 1st𝑔 ) = ( 𝑠𝐹 ) ∧ ( 2nd𝑔 ) = 0 ) ↔ ( ∃ 𝑠𝐸 ( 1st𝑔 ) = ( 𝑠𝐹 ) ∧ ( 2nd𝑔 ) = 0 ) )
11 fvex ( 1st𝑔 ) ∈ V
12 eqeq1 ( 𝑓 = ( 1st𝑔 ) → ( 𝑓 = ( 𝑠𝐹 ) ↔ ( 1st𝑔 ) = ( 𝑠𝐹 ) ) )
13 12 rexbidv ( 𝑓 = ( 1st𝑔 ) → ( ∃ 𝑠𝐸 𝑓 = ( 𝑠𝐹 ) ↔ ∃ 𝑠𝐸 ( 1st𝑔 ) = ( 𝑠𝐹 ) ) )
14 11 13 elab ( ( 1st𝑔 ) ∈ { 𝑓 ∣ ∃ 𝑠𝐸 𝑓 = ( 𝑠𝐹 ) } ↔ ∃ 𝑠𝐸 ( 1st𝑔 ) = ( 𝑠𝐹 ) )
15 1 2 3 4 5 dva1dim ( ( ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) ∧ 𝐹𝑇 ) → { 𝑓 ∣ ∃ 𝑠𝐸 𝑓 = ( 𝑠𝐹 ) } = { 𝑓𝑇 ∣ ( 𝑅𝑓 ) ( 𝑅𝐹 ) } )
16 15 adantr ( ( ( ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) ∧ 𝐹𝑇 ) ∧ 𝑔 ∈ ( 𝑇 × 𝐸 ) ) → { 𝑓 ∣ ∃ 𝑠𝐸 𝑓 = ( 𝑠𝐹 ) } = { 𝑓𝑇 ∣ ( 𝑅𝑓 ) ( 𝑅𝐹 ) } )
17 16 eleq2d ( ( ( ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) ∧ 𝐹𝑇 ) ∧ 𝑔 ∈ ( 𝑇 × 𝐸 ) ) → ( ( 1st𝑔 ) ∈ { 𝑓 ∣ ∃ 𝑠𝐸 𝑓 = ( 𝑠𝐹 ) } ↔ ( 1st𝑔 ) ∈ { 𝑓𝑇 ∣ ( 𝑅𝑓 ) ( 𝑅𝐹 ) } ) )
18 14 17 bitr3id ( ( ( ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) ∧ 𝐹𝑇 ) ∧ 𝑔 ∈ ( 𝑇 × 𝐸 ) ) → ( ∃ 𝑠𝐸 ( 1st𝑔 ) = ( 𝑠𝐹 ) ↔ ( 1st𝑔 ) ∈ { 𝑓𝑇 ∣ ( 𝑅𝑓 ) ( 𝑅𝐹 ) } ) )
19 xp1st ( 𝑔 ∈ ( 𝑇 × 𝐸 ) → ( 1st𝑔 ) ∈ 𝑇 )
20 19 adantl ( ( ( ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) ∧ 𝐹𝑇 ) ∧ 𝑔 ∈ ( 𝑇 × 𝐸 ) ) → ( 1st𝑔 ) ∈ 𝑇 )
21 fveq2 ( 𝑓 = ( 1st𝑔 ) → ( 𝑅𝑓 ) = ( 𝑅 ‘ ( 1st𝑔 ) ) )
22 21 breq1d ( 𝑓 = ( 1st𝑔 ) → ( ( 𝑅𝑓 ) ( 𝑅𝐹 ) ↔ ( 𝑅 ‘ ( 1st𝑔 ) ) ( 𝑅𝐹 ) ) )
23 22 elrab3 ( ( 1st𝑔 ) ∈ 𝑇 → ( ( 1st𝑔 ) ∈ { 𝑓𝑇 ∣ ( 𝑅𝑓 ) ( 𝑅𝐹 ) } ↔ ( 𝑅 ‘ ( 1st𝑔 ) ) ( 𝑅𝐹 ) ) )
24 20 23 syl ( ( ( ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) ∧ 𝐹𝑇 ) ∧ 𝑔 ∈ ( 𝑇 × 𝐸 ) ) → ( ( 1st𝑔 ) ∈ { 𝑓𝑇 ∣ ( 𝑅𝑓 ) ( 𝑅𝐹 ) } ↔ ( 𝑅 ‘ ( 1st𝑔 ) ) ( 𝑅𝐹 ) ) )
25 18 24 bitrd ( ( ( ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) ∧ 𝐹𝑇 ) ∧ 𝑔 ∈ ( 𝑇 × 𝐸 ) ) → ( ∃ 𝑠𝐸 ( 1st𝑔 ) = ( 𝑠𝐹 ) ↔ ( 𝑅 ‘ ( 1st𝑔 ) ) ( 𝑅𝐹 ) ) )
26 25 anbi1d ( ( ( ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) ∧ 𝐹𝑇 ) ∧ 𝑔 ∈ ( 𝑇 × 𝐸 ) ) → ( ( ∃ 𝑠𝐸 ( 1st𝑔 ) = ( 𝑠𝐹 ) ∧ ( 2nd𝑔 ) = 0 ) ↔ ( ( 𝑅 ‘ ( 1st𝑔 ) ) ( 𝑅𝐹 ) ∧ ( 2nd𝑔 ) = 0 ) ) )
27 10 26 syl5bb ( ( ( ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) ∧ 𝐹𝑇 ) ∧ 𝑔 ∈ ( 𝑇 × 𝐸 ) ) → ( ∃ 𝑠𝐸 ( ( 1st𝑔 ) = ( 𝑠𝐹 ) ∧ ( 2nd𝑔 ) = 0 ) ↔ ( ( 𝑅 ‘ ( 1st𝑔 ) ) ( 𝑅𝐹 ) ∧ ( 2nd𝑔 ) = 0 ) ) )
28 9 27 bitrd ( ( ( ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) ∧ 𝐹𝑇 ) ∧ 𝑔 ∈ ( 𝑇 × 𝐸 ) ) → ( ∃ 𝑠𝐸 𝑔 = ⟨ ( 𝑠𝐹 ) , 0 ⟩ ↔ ( ( 𝑅 ‘ ( 1st𝑔 ) ) ( 𝑅𝐹 ) ∧ ( 2nd𝑔 ) = 0 ) ) )
29 28 rabbidva ( ( ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) ∧ 𝐹𝑇 ) → { 𝑔 ∈ ( 𝑇 × 𝐸 ) ∣ ∃ 𝑠𝐸 𝑔 = ⟨ ( 𝑠𝐹 ) , 0 ⟩ } = { 𝑔 ∈ ( 𝑇 × 𝐸 ) ∣ ( ( 𝑅 ‘ ( 1st𝑔 ) ) ( 𝑅𝐹 ) ∧ ( 2nd𝑔 ) = 0 ) } )