$\left\{\begin{matrix}h=-\frac{3}{4ent\cos(\theta )}\text{, }&n\neq 0\text{ and }t\neq 0\text{ and }\nexists n_{1}\in \mathrm{Z}\text{ : }\theta =\pi n_{1}+\frac{\pi }{2}\\h\in \mathrm{R}\text{, }&\exists n_{2}\in \mathrm{Z}\text{ : }\theta =\pi n_{2}\end{matrix}\right.$

$\left\{\begin{matrix}n=-\frac{3}{4eht\cos(\theta )}\text{, }&h\neq 0\text{ and }t\neq 0\text{ and }\nexists n_{1}\in \mathrm{Z}\text{ : }\theta =\pi n_{1}+\frac{\pi }{2}\\n\in \mathrm{R}\text{, }&\exists n_{2}\in \mathrm{Z}\text{ : }\theta =\pi n_{2}\end{matrix}\right.$