If A=then A-1=?
= 3 x (0 - 2) – 4 x (2-4)+1 x (-1)
= -6+8-1
= 1
C11 = -2 C12 = 2 C13= -1
C21= -9 C22 = 8 C23= -5
C31= -8 C32=7 C33 =-4
Cofactor (A)= [ ]
Adj A = [ ]’
=[ ]
A-1= adj A
= [ ]