Metamath Proof Explorer


Theorem mdoc2i

Description: Orthocomplements form a modular pair. (Contributed by NM, 29-Apr-2006) (New usage is discouraged.)

Ref Expression
Hypothesis mdoc1.1 𝐴C
Assertion mdoc2i ( ⊥ ‘ 𝐴 ) 𝑀 𝐴

Proof

Step Hyp Ref Expression
1 mdoc1.1 𝐴C
2 1 choccli ( ⊥ ‘ 𝐴 ) ∈ C
3 2 mdoc1i ( ⊥ ‘ 𝐴 ) 𝑀 ( ⊥ ‘ ( ⊥ ‘ 𝐴 ) )
4 1 ococi ( ⊥ ‘ ( ⊥ ‘ 𝐴 ) ) = 𝐴
5 3 4 breqtri ( ⊥ ‘ 𝐴 ) 𝑀 𝐴