Chapter 10.2, Problem 7E

To determine

To check: Whether the matrix $\left[\begin{array}{ccc}\frac{1}{3}& 0& \frac{1}{2}\\ \frac{1}{3}& \frac{1}{2}& \frac{1}{2}\\ \frac{1}{3}& \frac{1}{2}& 0\end{array}\right]$ is regular.