Indefinite integral substitution

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evaluate the indefinite integral ((e^x)/((e^x)+1))dx

I let u = ((e^x)+1)

then

du = (e^x)dx

which occurs in the original equation so..

indefinite ingegral ((u^-1)du)

taking the antiderivative I get 1 + C

is this right? thanks!
 
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\int \frac{e^{x}}{e^{x}+1} dx

it should be \ln|e^{x}+1| + C because it is of the form \int \frac{du}{u}
 
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