$$
\frac{\left(\sigma^{\prime }\right)^{2}}{Q}\left[H\left(\frac{R-\mu^{\prime \prime}}{\sigma^{\prime\prime}}\right)-H\left(\frac{R+Q-\mu^{\prime \prime}}{\sigma^{\prime\prime}}\right)\right]-\frac{\left(\sigma^{\prime}\right)^{2}}{Q}\left[H \frac{R-\mu^{\prime}}{\sigma^{\prime}}-H\left(\frac{R+Q-\mu^{\prime}}{\sigma^{\prime}}\right)\right]
$$