Решим уравнение (2cosx+1) (√3 tgx+1)=0.
$$2cosx+1 = 0$$
$$cosx = -\frac{1}{2}$$
$$x = \pm arccos(-\frac{1}{2}) + 2\pi n, n \in Z$$
$$x = \pm (\pi - arccos(\frac{1}{2})) + 2\pi n, n \in Z$$
$$x = \pm (\pi - \frac{\pi}{3}) + 2\pi n, n \in Z$$
$$x = \pm \frac{2\pi}{3} + 2\pi n, n \in Z$$
$$\sqrt{3} tgx+1 = 0$$
$$tgx = -\frac{1}{\sqrt{3}}$$
$$x = arctg(-\frac{1}{\sqrt{3}}) + \pi n, n \in Z$$
$$x = -\frac{\pi}{6} + \pi n, n \in Z$$
Ответ: $$x = \pm \frac{2\pi}{3} + 2\pi n, n \in Z$$, $$x = -\frac{\pi}{6} + \pi n, n \in Z$$