| Exam Board | CAIE |
| Module | FP1 (Further Pure Mathematics 1) |
| Year | 2013 |
| Session | June |
| Topic | Invariant lines and eigenvalues and vectors |
6 The matrix \(\mathbf { A }\) is given by
$$\mathbf { A } = \left( \begin{array} { l l l }
4 & - 5 & 3
3 & - 4 & 3
1 & - 1 & 2
\end{array} \right)$$
Show that \(\mathbf { e } = \left( \begin{array} { l } 1
1
1 \end{array} \right)\) is an eigenvector of \(\mathbf { A }\) and state the corresponding eigenvalue.
Find the other two eigenvalues of \(\mathbf { A }\).
The matrix \(\mathbf { B }\) is given by
$$\mathbf { B } = \left( \begin{array} { r r r }
- 1 & 4 & 0
- 1 & 3 & 1
1 & - 1 & 3
\end{array} \right)$$
Show that \(\mathbf { e }\) is an eigenvector of \(\mathbf { B }\) and deduce an eigenvector of the matrix \(\mathbf { A B }\), stating the corresponding eigenvalue.