積分をしてみる　

$$\begin{align} \int \left ( \frac{x+2}{x} \right )^2 dx &= \int \left (1 + \frac{2}{x} \right )^2 dx \\ &= \int \left ( 1 + \frac{4}{x} + \frac{4}{x^2} \right ) dx \\ &= x + 4 \log |x| – \frac{4}{x} + C \end{align}$$