:: deftheorem Def5 defines Ort_Comp DUALSP06:def 5 :
for V being RealNormSpace
for W being Subspace of V
for b₃ being strict Subspace of DualSp V holds
( b₃ = Ort_Comp W iff the carrier of b₃ = { v where v is VECTOR of (DualSp V) : for w being VECTOR of V st w in W holds
w,v are_orthogonal } );