Explanation
\begin{aligned}
\int_{\frac{\pi}{6}}^{\frac{\pi}{3}} \sqrt{1 - \sin 2x} \, dx &= \alpha + \beta\sqrt{2} + \gamma\sqrt{3} \\
\text{let } \quad I &= \int_{\frac{\pi}{6}}^{\frac{\pi}{3}} \sqrt{1 - \sin 2x} \, dx \\
&= \int_{\frac{\pi}{6}}^{\frac{\pi}{3}} |\sin x - \cos x| \, dx \\
&= \int_{\frac{\pi}{6}}^{\frac{\pi}{4}} (\cos x - \sin x) \, dx + \int_{\frac{\pi}{4}}^{\frac{\pi}{3}} (\sin x - \cos x) \, dx \\
&= [\sin x + \cos x]_{\frac{\pi}{6}}^{\frac{\pi}{4}} - [\cos x + \sin x]_{\frac{\pi}{4}}^{\frac{\pi}{3}}
\end{aligned}
\begin{aligned}
& =\left(\sqrt{2}-\frac{1}{2}-\frac{\sqrt{3}}{2}\right)-\left(\frac{1}{2}+\frac{\sqrt{3}}{2}-\sqrt{2}\right) \\
& =2\sqrt{2}-1-\sqrt{3} \\
& \alpha=-1 \\
& \mathbf{\beta}=2 \\
& \text{一}=-1 \\
& 3\alpha+4\beta-\gamma=-3+8+1 \\
& =6
\end{aligned}