Metamath Proof Explorer


Theorem lcd1

Description: The unit scalar of the closed kernel dual of a vector space. (Contributed by NM, 20-Mar-2015)

Ref Expression
Hypotheses lcd1.h 𝐻 = ( LHyp ‘ 𝐾 )
lcd1.u 𝑈 = ( ( DVecH ‘ 𝐾 ) ‘ 𝑊 )
lcd1.f 𝐹 = ( Scalar ‘ 𝑈 )
lcd1.j 1 = ( 1r𝐹 )
lcd1.c 𝐶 = ( ( LCDual ‘ 𝐾 ) ‘ 𝑊 )
lcd1.s 𝑆 = ( Scalar ‘ 𝐶 )
lcd1.i 𝐼 = ( 1r𝑆 )
lcd1.k ( 𝜑 → ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) )
Assertion lcd1 ( 𝜑𝐼 = 1 )

Proof

Step Hyp Ref Expression
1 lcd1.h 𝐻 = ( LHyp ‘ 𝐾 )
2 lcd1.u 𝑈 = ( ( DVecH ‘ 𝐾 ) ‘ 𝑊 )
3 lcd1.f 𝐹 = ( Scalar ‘ 𝑈 )
4 lcd1.j 1 = ( 1r𝐹 )
5 lcd1.c 𝐶 = ( ( LCDual ‘ 𝐾 ) ‘ 𝑊 )
6 lcd1.s 𝑆 = ( Scalar ‘ 𝐶 )
7 lcd1.i 𝐼 = ( 1r𝑆 )
8 lcd1.k ( 𝜑 → ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) )
9 eqid ( oppr𝐹 ) = ( oppr𝐹 )
10 1 2 3 9 5 6 8 lcdsca ( 𝜑𝑆 = ( oppr𝐹 ) )
11 10 fveq2d ( 𝜑 → ( 1r𝑆 ) = ( 1r ‘ ( oppr𝐹 ) ) )
12 9 4 oppr1 1 = ( 1r ‘ ( oppr𝐹 ) )
13 11 7 12 3eqtr4g ( 𝜑𝐼 = 1 )