Đáp án: $\begin{array}{l}0,25{x^3} + {x^2} + x = 0\\x.\left( {0,25{x^2} + x + 1} \right) = 0\\ \Rightarrow \left[ \begin{array}{l}x = 0\\0,25{x^2} + x + 1 = 0\end{array} \right.\\Khi:0,25{x^2} + x + 1 = 0\\ \Rightarrow 4\left( {0,25{x^2} + x + 1} \right) = 0\\ \Rightarrow {x^2} + 4x + 4 = 0\\ \Rightarrow {\left( {x + 2} \right)^2} = 0\\ \Rightarrow x + 2 = 0\\ \Rightarrow x = – 2\\Vay\,x = 0\,;x = – 2\end{array}$ Reply
Đáp án:
$\begin{array}{l}
0,25{x^3} + {x^2} + x = 0\\
x.\left( {0,25{x^2} + x + 1} \right) = 0\\
\Rightarrow \left[ \begin{array}{l}
x = 0\\
0,25{x^2} + x + 1 = 0
\end{array} \right.\\
Khi:0,25{x^2} + x + 1 = 0\\
\Rightarrow 4\left( {0,25{x^2} + x + 1} \right) = 0\\
\Rightarrow {x^2} + 4x + 4 = 0\\
\Rightarrow {\left( {x + 2} \right)^2} = 0\\
\Rightarrow x + 2 = 0\\
\Rightarrow x = – 2\\
Vay\,x = 0\,;x = – 2
\end{array}$