Question

Cine ma poate ajuta cu aceasta problema? : Sa se rezolve in multimea [0,2pi) ecuatia sinx=-1/2
Scuze cu am gasit simbol pentru Pi.

Answer 1

$sinx=- \frac{1}{2} =>sinx=-sin \frac{\pi}{6}=>sinx+sin \frac{\pi}{6}=0=> 2sin \frac{x+ \frac{\pi}{6} }{2} \cdot cos \frac{x-\frac{\pi}{6}}{2}=0$
$sin \frac{x+ \frac{\pi}{6} }{2}=0=>\frac{x+ \frac{\pi}{6} }{2}=0 sau \pi=>x=2\pi-\frac{\pi}{6}= \frac{11\pi}{6}$
$cos \frac{x-\frac{\pi}{6}}{2}=0=>\frac{x-\frac{\pi}{6}}{2}= \frac{\pi}{2} sau \frac{3\pi}{2} =>x=\pi+ \frac{\pi}{6} = \frac{7\pi}{6}$