deletions | additions       diff --git a/Eigenvalues.tex b/Eigenvalues.tex  index b556d2e..1d68f96 100644  --- a/Eigenvalues.tex  +++ b/Eigenvalues.tex 
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\end{equation}  Consider the use of an object $|[A_11,A_22]|=A_11A_22-A_12A_21$... $|[A_{11},A_{22}]|=A_{11}A_{22}-A_{12}A_{21}$...