Metamath Proof Explorer


Theorem bracnvbra

Description: The bra of the converse bra of a continuous linear functional. (Contributed by NM, 31-May-2006) (New usage is discouraged.)

Ref Expression
Assertion bracnvbra ( 𝑇 ∈ ( LinFn ∩ ContFn ) → ( bra ‘ ( bra ‘ 𝑇 ) ) = 𝑇 )

Proof

Step Hyp Ref Expression
1 bra11 bra : ℋ –1-1-onto→ ( LinFn ∩ ContFn )
2 f1ocnvfv2 ( ( bra : ℋ –1-1-onto→ ( LinFn ∩ ContFn ) ∧ 𝑇 ∈ ( LinFn ∩ ContFn ) ) → ( bra ‘ ( bra ‘ 𝑇 ) ) = 𝑇 )
3 1 2 mpan ( 𝑇 ∈ ( LinFn ∩ ContFn ) → ( bra ‘ ( bra ‘ 𝑇 ) ) = 𝑇 )