Question

\(\dfrac{1}{x-1}-\dfrac{3}{x-2}=\dfrac{1}{\left(x-1\right)\left(x-2\right)}\)

Answer 1

\(\Leftrightarrow\left(x-2\right)-3\left(x-1\right)=1\left(đk:x\ne1,2\right)\)

\(\Leftrightarrow x-2-3x-3-1=0\)

\(\Leftrightarrow-2x-6=0\)

\(\Leftrightarrow x=-3\)