Question

Tìm x:

\(\text{​​}\text{​​}2x.\left(\frac{3}{-4}-\frac{1}{2}.x\right)=0\)

Answer 1

Ta có: \(2x\left(\frac{3}{-4}-\frac{1}{2}x\right)=0\)

mà 2>0

nên \(\left[{}\begin{matrix}x=0\\\frac{3}{-4}-\frac{1}{2}x=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=0\\-\frac{3}{4}-\frac{1}{2}x=0\end{matrix}\right.\)\(\Leftrightarrow\left[{}\begin{matrix}x=0\\\frac{1}{2}x=-\frac{3}{4}\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=0\\x=\frac{-3}{4}:\frac{1}{2}=\frac{-3}{4}\cdot2=-\frac{6}{4}=-\frac{3}{2}\end{matrix}\right.\)

Vậy: \(x\in\left\{0;\frac{-3}{2}\right\}\)