Don't know the steps in finding this derivative.
But the derivative is
The answer is:
5*x x *(5 + 5*log(x))
5*x /1 2\
5*x *|- + 5*(1 + log(x)) |
\x /
5*x / 1 3 15*(1 + log(x))\
5*x *|- -- + 25*(1 + log(x)) + ---------------|
| 2 x |
\ x /