Question

Решить уравнение cos 3/x=√2/2

Answer 1

Cos$\frac{3}{x}$=$\frac{\sqrt{2}} {2}$
$\frac{3}{x}$=±arccos($\frac{\sqrt{2}} {2}$)+$2 \pi n$
$\frac{3}{x}$=±$\frac{\pi} {4} +2 \pi n$
x=±$\frac{\pi} {12}+[tex] \frac{2}{3} \pi n$