y=cosvarphi/tany eching

$$y = \frac { \cos \varphi } { \tan y }$$

φ uchun yechish

$$\phi =-\arccos(y\tan(y))+2\pi n_{3}\text{, }n_{3}\in \mathrm{Z}$$

$$\phi =\arccos(y\tan(y))+2\pi n_{4}\text{, }n_{4}\in \mathrm{Z}\text{, }\nexists n_{2}\in \mathrm{Z}\text{ : }y=\frac{\pi n_{2}}{2}\text{ and }\exists n_{1}\in \mathrm{Z}\text{ : }\left(y>\frac{\pi n_{1}}{2}\text{ and }y<\frac{\pi \left(n_{1}+1\right)}{2}\right)\text{ and }\frac{|y||\sin(y)|}{|\cos(y)|}\leq 1$$