\(\dfrac{1}{xy-x^2}-\dfrac{1}{y^2-xy}\\ \dfrac{x^2-4}{3x+12}.\dfrac{x+4}{2x-4}\)

rút gọn

\(\dfrac{x^2}{x^2-1}+\dfrac{x}{\left(1-x\right)\left(x+1\right)}\)

\(\dfrac{3}{2x+6}-\dfrac{x-3}{x^2+3x}\)

\(\dfrac{1}{1-x}+\dfrac{2x}{x^2-1}\)

rút gọn

\(\dfrac{x}{x+2}+\dfrac{7x-16}{\left(x+2\right)\left(4x-7\right)}\)

\(\dfrac{x}{x-2}+\dfrac{2}{2-x}\)