回復 1# P78961118 的帖子
\(\begin{align}
& \angle AEB=\alpha +\beta \\
& \frac{\overline{AB}}{\overline{AC}}=\frac{\sin \beta }{\sin \left( \alpha +\beta \right)}=\frac{\overline{AE}}{\overline{AB}}=\frac{\frac{1}{2}\overline{AC}}{\overline{AB}} \\
& \overline{AB}=\frac{1}{\sqrt{2}}\overline{AC} \\
& \frac{\sin \beta }{\sin \left( \alpha +\beta \right)}=\frac{\sqrt{2}}{2} \\
\end{align}\)
