Metamath Proof Explorer


Theorem shocsh

Description: The orthogonal complement of a subspace is a subspace. Part of Remark 3.12 of Beran p. 107. (Contributed by NM, 10-Oct-1999) (New usage is discouraged.)

Ref Expression
Assertion shocsh ( 𝐴 ∈ Sℋ → ( ⊥ ‘ 𝐴 ) ∈ Sℋ )

Proof

Step Hyp Ref Expression
1 shss ⊢ ( 𝐴 ∈ Sℋ → 𝐴 ⊆ ℋ )
2 ocsh ⊢ ( 𝐴 ⊆ ℋ → ( ⊥ ‘ 𝐴 ) ∈ Sℋ )
3 1 2 syl ⊢ ( 𝐴 ∈ Sℋ → ( ⊥ ‘ 𝐴 ) ∈ Sℋ )