Question

me ajudeeem poor favor

Answer 1

Explicação passo-a-passo:

Calculando os determinante(Regra de Sarrus):

a)

$detA=\left|\begin{array}{ccc}-1&0&2\\6&4&1\\-2&-1&1\end{array}\right|\left\begin{array}{ccc}-1&0\\6&4\\-2&-1\end{array}\right|$

$detA=(-1).4.1+0.1.(-2)+2.6.(-1)-0.6.1-(-1).1.(-1)-2.4.(-2)\\\\detA=-4+0-12-0-1+16\\\\detA=-1$

b)

$detB=\left|\begin{array}{ccc}3&1&0\\0&2&3\\5&2&1\end{array}\right|\left\begin{array}{ccc}3&1\\0&2\\5&2\end{array}\right|$

$detB=3.2.1+1.3.5+0.0.2-1.0.1-3.3.2-0.2.5\\\\detB=6+15+0-0-18-0\\\\detB=3$

c)

$detC=\left|\begin{array}{ccc}-1&0&2\\0&1&4\\-2&-1&1\end{array}\right|\left\begin{array}{ccc}-1&0\\0&1\\-2&-1\end{array}\right|$

$detC=-1.1.1+0.4.(-2)+2.0.(-1)-0.0.1-(-1).4.(-1)-2.1.(-2)\\\\detC=-1+0+0-0-4+4\\\\detC=-1$