Edexcel FP2 2022 June — Question 2

Exam BoardEdexcel
ModuleFP2 (Further Pure Mathematics 2)
Year2022
SessionJune
TopicInvariant lines and eigenvalues and vectors

  1. Matrix \(\mathbf { M }\) is given by
$$\mathbf { M } = \left( \begin{array} { r r r } 1 & 0 & a
- 3 & b & 1
0 & 1 & a \end{array} \right)$$ where \(a\) and \(b\) are integers, such that \(a < b\)
Given that the characteristic equation for \(\mathbf { M }\) is $$\lambda ^ { 3 } - 7 \lambda ^ { 2 } + 13 \lambda + c = 0$$ where \(c\) is a constant,
  1. determine the values of \(a , b\) and \(c\).
  2. Hence, using the Cayley-Hamilton theorem, determine the matrix \(\mathbf { M } ^ { - 1 }\)