101-成大-化熱-No.5

Consider a binary solution. Let $x_i$ and $\gamma_i$ be the mole fraction and the activity coefficient of component $i$, respectively. Please estimate the integral :
\begin{align*}
\int_{x_1 = 0}^{x_1 = 1} \ln \left( \frac{\gamma_1}{\gamma_2} \right) \cdot dx_1
\end{align*}