The cubic f(x) = x3 +bx2 +cx+d satisfies f(1) = 3, f(2) = 6, and f(4) = 12. Compute f(3).	Choose one:
A) 6  B) 7  C) 8  D) 9  E) 10
Note that f(x) - 3x = (x - 1)(x- 2)(x - 4), so f(x) = (x - 1)(x - 2)(x- 4) + 3x   and therefore f(3) = 2 *1 *(-1) + 9= 
<gadget id="calculator">2 *1 *(-1) + 9</gadget>
<output>7</output>
7 .   correct answer 7
<result>B</result>
The cubic f(x) = x3 +bx2 +cx+d satisfies f(1) = 3, f(2) = 6, and f(4) = 12. Compute f(3).