def METHOD_NAME(self, A):
    C = inv(A)
    detA = sum((-A[i, 0]*A[0, i] if i !=0 else A[i-1, -1]*A[i, 0]) for i in (0,1))
    D = as_matrix([[(-A[i,j] if i != j else A[i,j]) for j in (-1,0)] for i in (-1,0)]) / detA  # FIXME: Test fails probably due to integer division
    self.assertEqualValues(C, D)