Question

Giải phương trình

\(3x-5\sqrt{x}=0\)

Answer 1

ĐKXĐ: x≥0

Ta có: \(3x-5\sqrt{x}=0\)

\(\Leftrightarrow\sqrt{x}\left(3\sqrt{x}-5\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}\sqrt{x}=0\\3\sqrt{x}-5=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=0\\3\sqrt{x}=5\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=0\\\sqrt{x}=\frac{5}{3}\end{matrix}\right.\)\(\Leftrightarrow\left[{}\begin{matrix}x=0\left(nhận\right)\\x=\frac{25}{9}\left(nhận\right)\end{matrix}\right.\)

Vậy: \(S=\left\{0;\frac{25}{9}\right\}\)