1
$\begingroup$

In the given matrix, only one eigen value is real. What is that eigen value ?

\begin{bmatrix} 1& 5& 4& 3& 2\\ 2& 1& 5& 4& 3\\ 3& 2& 1& 5& 4\\ 4& 3& 2& 1& 5\\ 5& 4& 3& 2& 1 \end{bmatrix}


Is there any small approach ?

  • 1
    @Moo, it just completely amazes me how some people can just pull up some obscure result like that so quickly.2017-02-06
  • 1
    Observe that the totals of the rows/columns are all equal. Act then by the matrix at the vector $x=(1,1,1,1,1)^T.$ You'll see that $Ax=15x,$ and so 15 is a real eigenvalue.2017-02-06

0 Answers 0