Let \(T: V \rightarrow V\) be linear. Let \(W\) be a \(T\) -invariant subspace of
\(V\) and \(\bar{T}\) the induced operator on \(V / W\). Prove
(a) The T-annihilator of \(v \in V\) divides the minimal polynomial of \(T\)
(b) The \(\bar{T}\) -annihilator of \(\bar{v} \in V / W\) divides the minimal
polynomial of \(T\)
(a) The \(T\) -annihilator of \(v \in V\) is the minimal polynomial of the
restriction of \(T\) to \(Z(v, T) ;\) therefore, by Problem \(10.6,\) it divides the
minimal polynomial of \(T\)
(b) The \(\bar{T}\) -annihilator of \(\bar{v} \in V / W\) divides the minimal
polynomial of \(\bar{T},\) which divides the minimal polynomial of \(T\) by
Theorem 10.16
Remark: In the case where the minimum polynomial of \(T\) is \(f(t)^{n},\) where
\(f(t)\) is a monic irreducible polynomial, then the \(T\) -annihilator of \(v \in
V\) and the \(\bar{T}\) -annihilator of \(\bar{v} \in V / W\) are of the form
\(f(t)^{m},\) where \(m \leq n\).