$\int\limits\frac{(x^2-2x)dx}{x^3+3x^2+2x}=\int \dfrac{x-2}{x^2 +3x+2}dx=\dfrac{1}{2}\int \dfrac{2x+3}{x^2+3x+2}dx-\dfrac{7}{2}\int \dfrac{1}{x^2+3x+2}dx$
$= \dfrac{1}{2}\int \dfrac{d(x^2+3x+2)}{x^2+3x+2}-\dfrac{7}{2}\int \dfrac{1}{(x+1)(x+2)}dx$
$=\dfrac{1}{2}\ln |x^2+3x+2|-\dfrac{7}{2} \int \bigg (\dfrac{1}{x+1}-\dfrac{1}{x+2} \bigg )dx$
đơn giản rồi tự làm nhé