Please give an example,such that:

and has the same eigenpolynomial as

but they don't have the same minimal polynomial (Bow)

Printable View

- Nov 5th 2009, 03:16 AMXingyuanGive an example
Please give an example,such that:

and has the same eigenpolynomial as

but they don't have the same minimal polynomial (Bow) - Nov 5th 2009, 04:37 AMHallsofIvy
In order to have the same minimal polynomial, the matrices must have the same eigenvalues. In order not to have the same characteristic polynomial, those eigenvalues must

**not**have the same multiplicity. Try two 3 by 3 matrices with two distinct eigenvalues, one of them of multiplicity 2.

(And you can make this problem really simple by using diagonal matrices.)