Let A = [aij] be a 3 × 3 matrix, where
aij = \(\begin{cases} 1, & if\, i=j \\ -x, & if\,|i-j|=1 \\ 2x+1, & otherwise. \end{cases}\)
1, if i = j
-x, if |i - j| = 1
2x+1, otherwise.
Let a function f : R → R be defined as f(x) = det(A). Then the sum of maximum and minimum values of f on R is equal to:
(1) -20/27
(2) 88/27
(3) 20/27
(4) -88/27