###### Example 4.2.1

We have seen that the matrix \(A = \left[\begin{array}{rr} 2 \amp 1 \\ 0 \amp 2 \\ \end{array}\right]\) has the characteristic equation \((2-\lambda)^2 = 0\text{.}\) This matrix \(A\) has a single eigenvalue \(\lambda = 2\text{,}\) which has multiplicity \(2\text{.}\)