a) \(\dfrac{2x-3}{x+5}\ge3\)
\(\Leftrightarrow\dfrac{2x-3}{x+5}-3\ge0\)
\(\Leftrightarrow\dfrac{2x-3-3x-15}{x+5}\ge0\)
\(\Leftrightarrow\dfrac{-x-18}{x+5}\ge0\Leftrightarrow-x-18\ge0\)
\(\Leftrightarrow x\le-18\)
Vậy...................
b) \(\dfrac{x-1}{x-3}>1\)
\(\Leftrightarrow\dfrac{x-1}{x-3}-1>0\)
\(\Leftrightarrow\dfrac{x-1-x+3}{x-3}>0\)
\(\Leftrightarrow\dfrac{2}{x-3}>0\Leftrightarrow x-3>0\Leftrightarrow x>3\)
Vậy..........