# Math Help - finding the integral-natural log

1. ## finding the integral-natural log

$\int {\ln (\sqrt x + \sqrt {1 + x} )dx}
$

I am thinking possibly a u sub but I have no idea what I could sub in.

2. Originally Posted by genlovesmusic09
$\int {\ln (\sqrt x + \sqrt {1 + x} )dx}
$

I am thinking possibly a u sub but I have no idea what I could sub in.
Try by parts with

$u=\ln(\sqrt{x}+\sqrt{x+1})$

$dv=1dx$

3. would the derivative of u=ln(sqrtx + sqrt1+x) be:
$\frac{{\frac{1}
{{2\sqrt x }} + 1}}
{{x + \sqrt x + 1}}
$

and if so how would i integrate that (timeing it by v=x)?

4. Originally Posted by VonNemo19
Try by parts with

$u=\ln(\sqrt{x}+\sqrt{x+1})$

$dv=1dx$
what would du be?