Below is the graph of f '(x), the derivative of f(x), and has x-intercepts at x = -3, x = 1 and x = 2 and a relative maximum at x = -1.5 and a relative minimum at x = 1.5. Which of the following statement is true? f is concave up from x = -1.5 to x = 1.5.
f has an inflection point at x = 1.5.
f has a relative maximum at x = -1.5.
None of these is true.