1) cos2x=1/2 2) sinx/3=√3/2 3) tgx/2=√3 4) ctg3x=√3/3 5) 4sinx+3=0 6) 7cosx-2=0 7)...

cos2x=1/2

2x = ± $\frac{\pi}{3}$ + 2 $\pi$ n, n ∈ Z

x = ± $\frac{\pi}{6}$ +

[tex]sinx \frac{x}{2} = \frac{\sqrt3}{2}" alt="\pi[/text]n, n ∈ Z

[tex]sinx \frac{x}{2} = \frac{\sqrt3}{2}" align="absmiddle" class="latex-formula">

$\frac{x}{2}$ = (-1)⁻n $\frac{\pi}{3} + \pi$ n, n ∈ Z

x = (-1)⁻n $\frac{2\pi}{3} + 2 \pi$ n, n ∈ Z

$tg \frac{x}{2} = \sqrt3$

$\frac{x}{2} = \frac{\pi}{3} + 2 \pi$ n, n ∈ Z

x = $\frac{2\pi}{3} + 4 \pi$ n, n ∈ Z