A [[Polynomial]] equation for a [[Matrix]] whose solutions are all [[Eigenvalue|Eigenvalues]] of the [[Matrix]].
$\huge \det(A-tI)=0 $
$\huge
c_{0}+c_{1}t+ \dots + c_{n}x^n = 0
$
$\huge x =\set {\lambda_{0}, \dots, \lambda_{i}} $
The [[Characteristic Polynomial]] of a [[Square]] $n\times n$ [[Matrix]] will always be of degree $n$.
#### Leading Terms
For some [[Matrix]] $A\in M_{n\times n}$
$\begin{align}
\det(A-\lambda I) &=
(-1)^n\lambda^n - (-1)^n\op{tr}(A)\lambda^{n-1}+\cdots \det(A) \\
\lambda &\in \C
\end{align}
$