Question

If A = [

−4 2
3 −7
] then

(a.) Find |A|
(b.) Find Adj A
(c) Find A
-1
(d) Is this a Singular Matrix?

Answer 1

Hello,

Explanation:

a)

`A=\begin{bmatrix}-4 & 2 \\3 & -7 \end{bmatrix}\\\\|A|=det \ A=-4*(-7)-3*2=28-6=22\\\\`

b)

`Adj\ A= \begin{bmatrix}-7 & 3 \\2 & -4 \end{bmatrix}\\`

c)

`A^(-1)=\begin{bmatrix}(-7)/(22) & (2)/(22) \\\\(3)/(22) & (-4)/(22) \end{bmatrix}`

d) Since A has an inverse, A is inversible and not singular.