Let a be a square matrix of order n, 2,4,..., 2n be the n eigenvalues of a, and calculate the value of determinant / a-3e /

Let a be a square matrix of order n, 2,4,..., 2n be the n eigenvalues of a, and calculate the value of determinant / a-3e /

Because 2,4,..., 2n are n eigenvalues of A,
So the special value of a-3e is
2-3=-1,4-3=1,6-3=3,8-3=5...,2n-3
So | a-3e | = - 1x1x3x5x... X (2n-3) = - 1x3x5x.. x (2n-3)