Integrating 1/(1+e^x):(adsbygoogle = window.adsbygoogle || []).push({});

I am currently substituting 1+e^x = u,

S (u*e^x)^-1 du since du/dx = e^x

S (u*(u-1))^-1 du (S represents the integral symbol)

But i looked up the answer and got Ln (e^x(1+e^x)) +c

i need to understand how this is done, thanks in advance everyone.

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# Integrating 1/(1+e^x)

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