`(1)/(1+e^(-x))`

int dx/((1+e^(x))(1+e^(-x))

int_(-1)^(1) (e^(|x|))/(1+a^(x))dx

underset(x to 0)"Lt" ((1)/(x)-(1)/(e^(x)-1))=

Let f(x) = (e^(x)+1)/(e^(x)-1) and int_0^(1)( (e^(x)+1)/(e^(x)-1)) x dx = lambda , then int_(-1)^(1) t f(t) dt =

I=int(dx)/((1+e^(x))(1+e^(-x)))=...

int(1)/(e^(x)(1+e^(-x)))dx=

Evaluate int(1-e^(x))/(1+e^(x)) dx.