Chapter 4.3, Problem 3EQ

In Exercises 1-12, compute (a) the characteristic polynomial of A, (b) the eigenvalues of A, (c) a basis for each eigenspace of A, and (d) the algebraic and geometric multiplicity of each eigenvalue.

$A=\left[\begin{array}{l}1\text{ 1 0}\\ \text{0}-\text{2 1}\\ \text{0 0 3}\end{array}\right]$