\(\begin{equation} \begin{array}{cc} a_n=2\sum_{k=1}^{n-1}\left\{\left(-1\right)^{k+1}\theta_k\right\}+\frac{1+\left(-1\right)^n}{2}\pi+\pi-\theta_0+2\pi m_1 \end{array} \end{equation}\)
\(\begin{equation} \begin{array}{cc} \beta_n=-\frac{\pi}{2}+\left(-1\right)^n\left[2\sum_{k=1}^{n-2}\left\{\left(-1\right)^{k+1}\cdot\theta_k\right\}+\theta_{n-1}+\pi-\theta_0\right]+2\pi m_2 \end{array} \end{equation}\)
When all modules are same, following relationship for \(\theta_n\) is established: