Limits For The Characteristic Roots Of A Matrix

In the recently published book of E. Bodewig, Matrix Calculus some results of the earlier parts of this paper are mentioned. It is stated there that they are of theoretical interest, but have no practical value. In this paper it will be shown that they can easily be used for practical computations.

Using the Separation Theorem for Hermitian matrices, intervals for each of the n characteristic roots are obtained. The method used is often simpler and gives better bounds than that of Ky Fan.