Solve the linear system \(\mathbf{A x}=\mathbf{b}\) by using

a. The inverse of the coefficient matrix.

b. 1 The "\" operator in MATLAB.

\(\mathbf{A}=\left[\begin{array}{ccc}2 & 1 & -2 \\ 3 & 0 & 2 \\ -1 & 2 & -1\end{array}\right], \mathbf{b}=\left\{\begin{array}{c}4 a \\ a \\ 0\end{array}\right\}, a=\) parameter