Question

Плиз 10 срочноо даю 30 баллов

Answer 1

cos(2p/9-4x/3)=√2/2

2p/9-4x/3=+-p/4+2pn

-4x/3=+-p/4-2p/9+2pn

x=+-3p/16+p/6-3pn/2 ; n принадлежит множеству целых чисел

Answer 2

$cos(\frac{2\pi}{9}-\frac{4x}{3})=\frac{\sqrt2}{2}\\\\\frac{2\pi}{9}-\frac{4x}{3}=\pm \frac{\pi}{4}+2\pi n,\; n\in Z\\\\\frac{4x}{3}=\frac{2\pi}{9}\pm \frac{\pi}{4}-2\pi n\; ,\; n\in Z\\\\x=\frac{\pi }{6}\pm \frac{3\pi }{16}-\frac{3\pi n}{2}\; ,\; n\in Z\; \; \Rightarrow \\\\x=\frac{17\pi }{48}-\frac{3\pi n}{2}\; \; \; ili\; \; \; x=-\frac{\pi }{48}-\frac{3\pi n}{2}\; ,\; n\in Z$