Find matrices A and B such that P(A + B) > P(A) + P(B) where P = spectral radius = max absolute value of eigenvalue
Choose:
$\displaystyle A=\begin{bmatrix}{0}&{0}\\{1}&{0}\end{bmatrix}\;,\ quad B=\begin{bmatrix}{0}&{1}\\{0}&{0}\end{bmatrix}$
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