Answer
0, no inverse.
Work Step by Step
Step 1. List the matrix needed:
$\begin{array} \\A=\\ \end{array}
\begin{bmatrix} 2&4&0\\ -1&1&2\\0&3&2 \end{bmatrix}$
Step 2. Calculate the determinant use row-1 expansion (use the formula from section 10.6):
$|A|=2(1\times2-2\times3)-4(-1\times2-0)+0=-8+8=0$
Step 3. Since $det(A)=|A|=0$, $A^{-1}$ does not exist.
