Linear Algebra and Its Applications · Problem 3.4.32
Orthogonality — Gilbert Strang
Mathematics · orthogonal-complement-subspace
Problem
(a) Find a basis for the subspace S in R4 spanned by all solutions of
x1+x2+x3−x4=0.
(b) Find a basis for the orthogonal complement S⊥.
(c) Find b1 in S and b2 in S⊥ so that b1+b2=b=(1,1,1,1).