The graph of f(x) = 2x3 β 19x2 + 57x β 54 is shown below.
On a coordinate plane, a graph of a function is in quadrants 1 and 4. The function goes through the x-axis at (2, 0), (3, ), and (4.5, 0).
How many roots of f(x) are rational numbers?
0
1
2
3