Solution (source code)

= Solution

On $(0,1)$ its absolute value is at most $x|\log x|$, which has integral $1/4$, by <integration by parts> or the substitution $x=e^{-t}$. The function is measurable and this majorant is <integrable>, so $\boxed{x\log x/(1+x)^2\text{ is integrable on }(0,1)}$.