Integrate the rational functions $\frac{2x}{x^2+3x+2}$
$\begin{array}{1 1} 4\log|x+2|-2\log|x+1|+c \\ 4\log|x+2|+2\log|x+1|+c \\ 2\log|x+2|-\log|x+1|+c \\2\log|x+2|+\log|x+1|+c \end{array}$