(1.1) |〈u,v〉| ≤ ‖u‖ ‖v‖. An outline of a proof of this fundamental inequality, when V = R and ‖ · ‖ is the standard Eucledian norm, is given in Exercise 24 of Section 2.7 of [1]. We will give a proof in the general case at the end of this section. LetW be an n dimensional subspace of V and let P : V 7→W be the corresponding projection operator, i.e. if v ∈ V then w = Pv ∈W is the element in W w...