deletions | additions       diff --git a/Eigenvalues.tex b/Eigenvalues.tex  index 67da075..aa1b926 100644  --- a/Eigenvalues.tex  +++ b/Eigenvalues.tex 
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\end{equation}  \begin{equation}  A^{-1} = \frac{1}{|A|}\sum_{s=0}^{n-1}A^{s}\sum_{k_1,k_2,\ldots ,k_{n-1}}\prod_{l=1}^{n-1} \frac{(-1)^{k_l+1}}{l^{k_l}k_{l}!}\mathrm{tr}(A^l)^{k_l},  \end{equation}  Consider the use of an object $|[A_{00},A_{11}]|=A_{00}A_{11}-A_{01}A_{10}$... Much like a commutator, something like a detutator, represents the determinant of a 2x2 matrix when trace elementsw are inserted.  Then for a 3x3 matrix the similar thing \begin{equation}