Question

Calcule o determinante da matriz 2x2 abaixo:​

Answer 1

$Det(A)=a_{11}\cdot a_{22}-a_{12}\cdot a_{21}\\\\\\\\Det(A)=(-1)\cdot8\;-(-4)\cdot2=-8+8=0$

Answer 2

Calcule o determinante da matriz abaixo:

$\Large\boxed{\begin{array}{l} \Large\boxed{\begin{array}{l} \rm \:A = \begin{bmatrix} - 1& - 4 \\ 2&8\end{bmatrix} \end{array}}\end{array}}$

Cálculos:

$\Large\boxed{\begin{array}{l} \Large\boxed{\begin{array}{l} \rm \:det(A) = - 1 \times 8 - ( - 4) \times 2 \\ \\ \rm \: det(A) = - 8 + 4 \times 2 \\ \\ \rm \:det(A) = - 8 + 8 \\ \\ \boxed{ \boxed{ \boxed{ \rm{det(A) = 0}}}} \end{array}}\end{array}}$