Problem:
Find the characteristic polynomial of the following matrix:
$\left(
\begin{array}{ccc}
 \frac{20}{7} & \frac{51}{7} & -\frac{17}{7} \\
 -\frac{48}{7} & \frac{53}{7} & -\frac{5}{7} \\
 \frac{9}{7} & \frac{16}{7} & \frac{31}{7} \\
\end{array}
\right)$
Answer:
$-x^3+\frac{104 x^2}{7}-\frac{6004 x}{49}+\frac{129218}{343}$
{'source': 'AMPS', 'file': 'amps/mathematica/linear_algebra/characteristic_polynomial/2375.txt'}