# Exercise Solution 2.13

- Expressed in matrix form [2.91], polynomial [2.93] becomes
[s1]

where

[s2]

[s3]

[s4]

- Applying the Cholesky algorithm, we obtain Cholesky matrix
[s5]

We conclude that the matrix

is positive definite.*c* - By [2.92]
[s6]

- 1
- Because the matrix
is positive definite, it is a minimum.*c*