Question

tìm điều kiện xác định \(\frac{-2}{5-\sqrt[]{2x}}\)

Answer 1

\(\frac{-2}{5-\sqrt{2x}}\) xác định \(\Leftrightarrow\left\{{}\begin{matrix}5-\sqrt{2x}\ne0\\\sqrt{2x}\ge0\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}\sqrt{2x}\ne5\\2x\ge0\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}2x\ne25\\x\ge0\end{matrix}\right.\)

\(\Leftrightarrow\left\{{}\begin{matrix}x\ne12,5\\x\ge0\end{matrix}\right.\)

Vậy \(\frac{-2}{5-\sqrt{2x}}\) xác định \(\Leftrightarrow\left\{x\in R|x\ge0;x\ne12,5\right\}\)