:: deftheorem Def6 defines Ort_Comp DUALSP06:def 6 :
for V being RealNormSpace
for W being Subspace of DualSp V
for b₃ being strict Subspace of V holds
( b₃ = Ort_Comp W iff the carrier of b₃ = { v where v is VECTOR of V : for w being VECTOR of (DualSp V) st w in W holds
v,w are_orthogonal } );