\[\begin{equation}
\begin{array}{cc}
\alpha_1 = \pi - \theta_0
\end{array}
\end{equation}\]
\(\begin{equation}
\begin{array}{cc}
\beta_1 = \frac{\pi}{2}
\end{array}
\end{equation}\)
By solving for (6-11), angles \(\alpha_n\) and \(\beta_n\)\(\) can be expressed as follows:
For \(n\ge2\), \(n\in N\), \(\)\(m_{1,}m_2\in Z\),