Question

mim ajudem por favor

Answer 1

Eu acho que é a D

Espero ajudar♡♡♡♡♡

Answer 2

Definindo a matriz A:

$a_{11} = (-1)^{1+1} = (-1)^2 = 1\\a_{12} = (-1)^{1+2} = (-1)^3 = -1\\a_{13} = (-1)^{1+3} = (-1)^4 = 1\\\\a_{21}=2 -1 = 1\\a_{22}=(-1)^{2+2} = (-1)^4 = 1\\a_{23}=(-1)^{2+3} = (-1)^5 = -1\\\\a_{31} = 3-1 = 2\\a_{32} = 3-2 = 1\\a_{33} = (-1)^{3+3} = (-1)^6 = 1$

$A = \left[\begin{array}{ccc}1&-1&1\\1&1&-1\\2&1&1\end{array}\right]$

Inversa de A:

$A^{-1} = \left[\begin{array}{ccc}1/2&1/2&0\\-3/4&-1/4&1/2\\-1/4&-3/4&1/2\end{array}\right]$

Determinante da inversa:

$\boxed{\det(A^{-1}) = \frac{1}{4}}$