Question

Sendo A=           1 3 2 0 1 2 2 3 0 , calcule det t A

Answer 1

Regra de Sarrus:

$D = \left[\begin{array}{ccc}1&3&2\\0&1&2\\2&3&0\end{array}\right] \left[\begin{array}{ccc}1&3\\0&1\\2&3\end{array}\right] \\\\\\D = (1 \cdot 1 \cdot 0 + 3 \cdot 2 \cdot 2 + 2 \cdot 0 \cdot 3)-(2 \cdot 1 \cdot 2 + 1 \cdot 2 \cdot 3 +3 \cdot 0 \cdot 0)\\D = (0 + 12+ 0)-(4+6+0)\\D = 12 - 10\\ \boxed{D = 2}$