Question

Tìm x: \(\left(x-2\right)\left(x+\dfrac{3}{4}\right)>0\)

Answer 1

\(\left(x-2\right)\left(x+\dfrac{3}{4}\right)>0\\ \Leftrightarrow\left[{}\begin{matrix}\left\{{}\begin{matrix}x-2>0\\x+\dfrac{3}{4}>0\end{matrix}\right.\\\left\{{}\begin{matrix}x-2< 0\\x+\dfrac{3}{4}< 0\end{matrix}\right.\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}\left\{{}\begin{matrix}x>2\\x>-\dfrac{3}{4}\end{matrix}\right.\\\left\{{}\begin{matrix}x< 2\\x< -\dfrac{3}{4}\end{matrix}\right.\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x>2\\x< 2\end{matrix}\right.\)

Vậy `x>2` hoặc `x<2`

Answer 2

x > 2 hoặc < 2