Question Number 71301 by turbo msup by abdo last updated on 13/Oct/19
$${let}\:{f}\left({x}\right)=\int_{\mathrm{1}+{x}} ^{\mathrm{1}+{x}^{\mathrm{2}} } \:\frac{{arctan}\left({xt}+\mathrm{2}\right)}{{x}+{t}}{dt} \\ $$$${calculate}\:{f}^{'} \left({x}\right) \\ $$$$\left.\mathrm{2}\right){find}\:{lim}_{{x}\rightarrow\mathrm{0}} {f}\left({x}\right) \\ $$