The table shows several value of the function f(x)=-x^3+x^2-x+2. Complete the missing values in his table, and then use these values and the intermediate value theorem to determine (an) interval(s) where the function must have a zero.
x -2 -1 0 1 2
f(x) 16 -4
My answer is (-infty,0) u (2,infty), but I think that I'm wrong. thanks for any help.