Evaluate ∫ex1+exdx\int \frac{e^x}{1+e^x} dx∫1+exexdx.
ln(1+ex)+C\ln(1+e^x) + Cln(1+ex)+C
ex+Ce^x + Cex+C
1/(1+ex)+C1/(1+e^x) + C1/(1+ex)+C
None