Question

dada a matriz A= 2 3 -1 2 , sendo At sua transposta , o determinante da matriz 2A.At é:

Answer 1

$2 \left|\begin{array}{ccc}2&3\\- 1&2\end{array}\right| . \left|\begin{array}{ccc}2&- 1\\3&2\end{array}\right| \\ \\ \left|\begin{array}{ccc}4&6\\- 2&4\end{array}\right| . \left|\begin{array}{ccc}2&- 1\\3&2\end{array}\right| = (16 + 12).(4 + 3) = 28.7 = 196$