Don't know the steps in finding this derivative.
But the derivative is
The answer is:
x
/ 2\ /x*(1 + 2*x) / 2\\
\x + x / *|----------- + log\x + x /|
| 2 |
\ x + x /
/ 2\
| 2*(1 + 2*x) (1 + 2*x) |
| 2 2 + ----------- - ----------|
x |/1 + 2*x \ x x*(1 + x) |
(x*(1 + x)) *||------- + log(x*(1 + x))| + ----------------------------|
\\ 1 + x / 1 + x /
/ 2 3 \
| 6*(1 + 2*x) 3*(1 + 2*x) 2*(1 + 2*x) / 2\|
| 6 - ----------- - ------------ + ------------ /1 + 2*x \ | 2*(1 + 2*x) (1 + 2*x) ||
| 3 1 + x x*(1 + x) 2 3*|------- + log(x*(1 + x))|*|2 + ----------- - ----------||
x |/1 + 2*x \ x*(1 + x) \ 1 + x / \ x x*(1 + x) /|
(x*(1 + x)) *||------- + log(x*(1 + x))| + --------------------------------------------- + -----------------------------------------------------------|
\\ 1 + x / x*(1 + x) 1 + x /