Answer
$${\left( {x + 4} \right)\left( {3{x^2} + 1} \right)}$$
Work Step by Step
$$\eqalign{
& \frac{{3x - 2}}{{\left( {x + 4} \right)\left( {3{x^2} + 1} \right)}} = \frac{A}{{x + 4}} + \frac{{Bx + C}}{{3{x^2} + 1}} \cr
& {\text{We should multiply by }}\left( {x + 4} \right)\left( {3{x^2} + 1} \right){\text{ to clear the denominators}}{\text{.}} \cr} $$
