Question 300297
[A]={{{(matrix(3,3,0,1,-1,2,-2,-1,-1,1,1))}}}
det([A])={{{-1}}} so an inverse does exist. 
[A]inv={{{(matrix(3,3,1,2,3,1,1,2,0,1,2))}}}
I used EXCEL's MINVERSE function to find the inverse of [A].