\(\left(\frac{3}{4}-2x\right)\left(\frac{-3}{5}+\frac{2}{-31}-\frac{17}{51}\right)\le0\)
\(\Leftrightarrow\)\(\frac{3}{4}-2x\ge0\) ( Vì: \(\frac{-3}{5}+\frac{2}{-31}-\frac{17}{51}< 0\) )
\(\Leftrightarrow-2x\le-\frac{3}{4}\)
\(\Leftrightarrow x\ge\frac{3}{2}\)
\(\begin{aligned} &\left(\frac{3}{4}-2 x\right)\left(-\frac{3}{5}+\frac{2}{-61}-\frac{17}{51}\right) \geq 0 \Leftrightarrow\left(\frac{3}{4}-\right. \\ &2 x)\left(-\frac{3}{5}-\frac{2}{61}-\frac{1}{3}\right) \geq 0 \Leftrightarrow\left(\frac{3}{4}-\right. \\ &2 x)\left(-\frac{549}{915}-\frac{335}{915}\right) \geq 0 \Leftrightarrow\left(\frac{3}{4}-\right. \\ &2 x)\left(-\frac{884}{915}\right) \geq 0 \Leftrightarrow\left(\frac{3}{4}-2 x\right) \leq 0 \Leftrightarrow x \geq \frac{3}{8} \end{aligned}\)
