Important properties of eigen values
1.Trace of matrix =sum of the eigen values.
2.Value of the determinant of a given matrix = product of eigen values.
3. Determinant of matrix \[A\]=\[A^t\]
4. For a lower and upper triangular matrix ,eigen values are diagonal elements of the upper and lower triangular matrix.
Example
\[ \begin{bmatrix}a&b&c\\0&f&c\\0&0&r\end{bmatrix}\]
trace of the matrix=a+f+r
eigen values of the matrix are a,f,r
