Question

integrate x*e^x

Answer 1

You can use integration by parts, are you familiar with this method?

Answer 2

\(\sf \color{red}{\rho = x}\) and \(\sf \color{blue}{d\sigma = e^x}\)
\(\sf \color{red}{d\rho ' = 1}\) and \(\sf \color{blue}{\sigma = e^x }\)
to put it all together: \(\sf \color{orange}{\rho\times\sigma - \int \sigma ~d\rho}\)

Answer 3

it should work tnx