Prove that if a \(3\times 3\) matrix \(A\) over \(\mathbb {Q}\) satisfies \(A^8=I\), then \(A^4=I\). Justify claims of irreducibility of polynomials.
Question
Math 6310 • Algebra
Spring 2018 • Question 7
Question
Spring 2018 • Question 7
Prove that if a \(3\times 3\) matrix \(A\) over \(\mathbb {Q}\) satisfies \(A^8=I\), then \(A^4=I\). Justify claims of irreducibility of polynomials.