\(\smallint \frac{{{\rm{dx}}}}{{1 + {{\rm{e}}^{ - {\rm{x}}}}}}\) is equal to
Where c is the constant of integration
1
1 + ex + c
2
In (1 + e-x) + c
3
In (1 + ex) + c
4
2 In (1 + e-x) + c
\(\smallint \frac{{{\rm{dx}}}}{{1 + {{\rm{e}}^{ - {\rm{x}}}}}}\) is equal to
Where c is the constant of integration