Exercise 6.3.19

Answers

Let $v_{i}$ be the $i$ -th column of $A$ . Then we have $v_{i}^{∗}$ is the $i$ -th row of $A^{∗}$ . And the desired result comes from the fact

{(A^{∗} A)}_{ij} = v_{i}^{∗} v_{j} = ⟨ v_{j}, v_{i} ⟩,

which is zero when $i \neq j$ .

jephianlin

2011-06-27 00:00