Question

FOTO DA PERGUNTA EM ANEXO
RÁPIDO PFV​

Answer 1

$A = \left[\begin{array}{ccc}-1&3\\7&4\end{array}\right] \\\\\\B = \left[\begin{array}{ccc}2&1\\-3&0\end{array}\right] \\\\\\\\a) det(A+B)\\\\A+B = \left[\begin{array}{ccc}1&4\\4&4\end{array}\right] \\\\\\det(A+B) = (1*4) - (4*4)\\det(A+B) = 4 - 16 = -12$

$b)3det(A)\\\\A = \left[\begin{array}{ccc}-1&3\\7&4\end{array}\right] \\\\\\det(A) = (-1*4) - (7*3)\\det(A) = -4 -21 = -25\\3det(A) = -25*3 = -75$

$c)det(3A)\\\\A = \left[\begin{array}{ccc}-1&3\\7&4\end{array}\right] \\\\\\3A = \left[\begin{array}{ccc}-3&9\\21&12\end{array}\right]\\\\det(3A) = (-3*12)-(21*9)\\\\det(3A) = (-36) - (189) = -225$

$d) A = \left[\begin{array}{ccc}-1&3\\7&4\end{array}\right] \\\\det(A) = -25\\\\B = \left[\begin{array}{ccc}2&1\\-3&0\end{array}\right] \\\\det(B) = 3\\\\d) det(A) + det(B) = -25+3 = -22$