Question

Calcule o valor dos determinantes de ordem 2:
a) $\left[\begin{array}{ccc} \sqrt{2} &4&\\-3& \sqrt{2} &\\&&\end{array}\right]$


b)$\left[\begin{array}{ccc} \frac{1}{7} & \frac{1}{7} &\\ \frac{1}{7} & \frac{1}{7} &\\&&\end{array}\right]$

Answer 1

a)

2 - (-12) = 
2 + 12 = 14

b)

1/49 - 1/49  =  0