Question

(x² + 2) . (x + 3) = 0

Answer 1

Vì : \(\left(x^2+2\right)\left(x+3\right)=0\)

\(\Rightarrow\left[\begin{matrix}x^2+2=0\\x+3=0\end{matrix}\right.\) \(\Leftrightarrow\left[\begin{matrix}x^2=-2\Rightarrow x\in\varnothing\\x=-3\end{matrix}\right.\)

Vậy x = -3

Answer 2

\(\left(x^2+2\right)\left(x+3\right)=0\)

\(\Rightarrow\left\{\begin{matrix}x^2+2=0\\x+3=0\end{matrix}\right.\Rightarrow\left\{\begin{matrix}x^2=-2\left(loại\right)\\x=-3\left(chọn\right)\end{matrix}\right.\)

Vậy x = -3