$\pm\frac{\pi}{2}+k\pi,k\in Z$

$\pm\pi k,k\in Z$

$2k\pi,k\in Z$

$\pm\frac{\pi}{4}+2k\pi,k\in Z$

$\left(-1\right)^k\arcsin\left(-2\right)\pm k\pi,k\in Z$

n-are solutii

$\pm2k\pi,k\in Z$

$\frac{\pi}{2}+2k\pi,k\in Z$

$R\ne\left\{\frac{\pi}{2}+k\pi,k\in Z\right\}$

$\left\{\frac{\pi}{2}+k\pi,k\in Z\right\}$

$R\ne\left\{k\pi,k\in Z\right\}$

$\left\{\pi k,k\in Z\right\}$

Trigonometrica fundamentala

Trigonometrica omogena

Trigonometrica reductibila la ecuatii algebrica

Nu este ecuatie trigonometrica

 $\left\{\pm\frac{\pi}{2}+k\pi,k\in Z\right\}$  

 $R$  

 $\left\{k\pi,k\in Z\right\}$  

Nu are solutii