$\displaystyle\int { \color{#FF6800}{ \dfrac { \ln { \left( x \right) } } { x } } } d { \color{#FF6800}{ x } }$
$ $ Calculate the integral of the logarithmic function using the formula of $ \int x^{-1} \ln(x)^{n} dx = \left[\int{u^{n}}d{u}\right]_{u=\ln{\left(x\right)}}$
$\left [ \displaystyle\int { \color{#FF6800}{ u } } d { \color{#FF6800}{ u } } \right ] _ { \color{#FF6800}{ u } = \ln { \left( \color{#FF6800}{ x } \right) } }$
$\left [ \displaystyle\int { \color{#FF6800}{ u } } d { \color{#FF6800}{ u } } \right ] _ { u = \ln { \left( x \right) } }$
$ $ Calculate the integral using the formula of $ \int{x^{n}}dx = \frac{x^{n+1}}{n+1}$