Question

Ajuda ,por favor..........

Answer 1

Resposta: Det A = 11

Explicação passo-a-passo:

Answer 2

Resposta:

51

Explicação passo-a-passo:

$\left[\begin{array}{ccc}1&3&1\\-2&3&1\\4&-2&5\end{array}\right] \\\\\\= \left[\begin{array}{ccc}1&3&1\\-2&3&1\\4&-2&5\end{array}\right] \left[\begin{array}{ccc}1&3\\-2&3\\4&-2\end{array}\right] \\\\\\= (1 . 3 . 5) + (3 . 1 . 4) + (1 . -2 . -2) - (1 . 3 . 4) - (1 . 1 . -2) - (3 . -2 . 5)\\\\= 15 + 12 + 4 - 12 + 2 + 30\\\\= 51$