Đáp án:
Giải thích các bước giải:
\(\begin{array}{l}
a.(2x + 1)({x^2} + 2) = 0\\
\to 2x + 1 = 0\\
\to x = - \frac{1}{2}\\
b.({x^2} + 4)(7x - 3) = 0\\
\to 7x - 3 = 0\\
\to x = \frac{3}{7}\\
c.({x^2} + x + 1)(6 - 2x) = 0\\
\to \left[ \begin{array}{l}
{x^2} + x + 1 > 0\forall x \in R\\
6 - 2x = 0
\end{array} \right.\\
\to x = 3\\
d.(8x - 4)({x^2} + 2x + 2) = 0\\
\to \left[ \begin{array}{l}
{x^2} + 2x + 2 > 0\forall x \in R\\
8x - 4 = 0
\end{array} \right.\\
\to x = \frac{1}{2}
\end{array}\)
