I have a matrix $A_{(3x3)}$ with determinant iqual to zero, null trace and their cofactors of the diaganal such that $\Delta_{11}=-1$, $\Delta_{22}=0$, $\Delta_{33}=-1$. Some TIPS to calculate the eigenvalues of the $A$ matrix?
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$\begingroup$The characteristic equation will be $$x^3-2x=0.$$ The $-2$ is $\Delta_{11}+\Delta_{22}+\Delta_{33}$.
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