This problem relates to finding derivative of the product (or ratio) of two functions:
f(x) = m(x)*n(x)
f(x)’ = m(x)*n(x)’ + n(x)*m(x)’
Therefore, pertinent to your problem definition:
f(x)’ = 2x* (-1/(x+3)2) + 2/(x+3) = 2/(x+3) - 2x/(x+3)2 + 2/3
Hope this will help.