Bài giải:

(3x – 1)(x² + 2) = (3x – 1)(7x – 10)

$\Leftrightarrow $(3x – 1)(x² + 2) – (3x – 1)(7x – 10) = 0

$\Leftrightarrow $(3x – 1)(x² + 2 – 7x + 10) = 0

$\Leftrightarrow $(3x – 1)(x² – 7x + 12) = 0

$\Leftrightarrow $(3x – 1)(x – 4)(x – 3) = 0

$\Leftrightarrow \left[ \begin{align}& 3x-1=0 \\ & x-4=0 \\ & x-3=0 \\\end{align} \right.$

$\Leftrightarrow \left[ \begin{align}& x=\frac{1}{3} \\ & x=4 \\ & x=3 \\\end{align} \right.$

Vậy đáp án đúng là: D