Salut ,de obicei cand apare ln x la o integrala ,e o practica foarte buna sa incerci sa folosesti integrarea prin parti.[tex]\displaystyle \int \left (\dfrac{x^{-3}}{-3}\right)' \cdot \ln x dx= -\dfrac{x^{-3}}{3}\cdot \ln x-\int \dfrac{x^{-3}}{-3} \cdot \dfrac{1}{x} dx= -\dfrac{x^{-3}}{3}\cdot \ln x+\dfrac{1}{3}\int x^{-4} =\\ -\dfrac{x^{-3}}{3}\cdot \ln x-\dfrac{x^{-3}}{9}+C[/tex]
