Question Number 34864 by a.i msup by abdo last updated on 12/May/18
$${let}\:{f}\left({x}\right)={x}\:{arctan}\left(\mathrm{1}+{e}^{−{x}} \right) \\ $$$${developp}\:{f}\:{at}\:{intrgr}\:{serie}\:. \\ $$
let-f-x-x-arctan-1-e-x-developp-f-at-intrgr-serie-