This will simplify our calculations. The only non-zero element in the second row is -2, which is in the first column. So, we have:
$$(-1)^{2+1} \times -2 \times \left|\begin{array}{rrr}
-1 & 1 & 2 \\
-1 & -2 & 3 \\
4 & 2 & 3
\end{array}\right|$$
This simplifies
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