Question

Решите уравнение: sin( -x/4)= -√2/2

Answer 1

$sin(-\frac{x}{4})=-\frac{\sqrt{2}}{2}$
$sin \frac{x}{4}=\frac{\sqrt{2}}{2}$
$\frac{x}{4}=(-1)^k*arcsin (\frac{\sqrt{2}}{2})+\pi*k$
$\frac{x}{4}=(-1)^k*\frac{\pi}{4}+\pi*k$
$x=(-1)^k*pi+4*\pi*k$
k є Z