CAIE Further Paper 2 2024 June — Question 8

Exam BoardCAIE
ModuleFurther Paper 2 (Further Paper 2)
Year2024
SessionJune
TopicInvariant lines and eigenvalues and vectors

8
  1. Find the set of values of \(a\) for which the system of equations $$\begin{array} { c l } 6 x + a y & = 3
    2 x - y & = 1
    x + 5 y + 4 z & = 2 \end{array}$$ has a unique solution.
  2. Show that the system of equations in part (a) is consistent for all values of \(a\).
    The matrix \(\mathbf { A }\) is given by $$\mathbf { A } = \left( \begin{array} { r r r } 6 & 0 & 0
    2 & - 1 & 0
    1 & 5 & 4 \end{array} \right)$$
  3. Find a matrix \(\mathbf { P }\) and a diagonal matrix \(\mathbf { D }\) such that \(( 14 \mathbf { A } + 24 \mathbf { I } ) ^ { 2 } = \mathbf { P D P } ^ { - 1 }\).
  4. Use the characteristic equation of \(\mathbf { A }\) to show that $$( 14 \mathbf { A } + 24 \mathbf { I } ) ^ { 2 } = \mathbf { A } ^ { 4 } ( \mathbf { A } + b \mathbf { I } ) ^ { 2 }$$ where \(b\) is an integer to be determined.
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