Ребята выручайте, срочно!!! 4sin(x + 60°) cosX = ctg1290° 

[latex]4sin(x+60к)*cosx=ctg1290к[/latex] [latex]4cos(\frac{\pi }{6}-x)*cosx= \sqrt{3} [/latex] [latex]cos(\frac{\pi }{6}-x)*cosx= \frac{ \sqrt{3} }{4} [/latex] [latex] \frac{1}{4}(\sqrt{3}+2cos(\frac{\pi}{6}-2x))= \frac{ \sqrt{3} }{4} [/latex] [latex] \sqrt{3} +2cos(\frac{\pi}{6}-2x)= \sqrt{3} [/latex] [latex]2cos(\frac{\pi}{6}-2x)= \sqrt{3} - \sqrt{3} [/latex] [latex]cos(\frac{\pi}{6}-2x)= \frac{ \sqrt{3} }{2} - \frac{ \sqrt{3} }{2} [/latex] [latex]\frac{\pi}{6}-2x= \frac{ \pi }{2}+ \pi n[/latex];    n∈Z [latex]-2x= \frac{ \pi }{3} + \pi n[/latex];   n∈Z [latex]x=- \frac{ \pi }{6} - \frac{ \pi n}{2} [/latex];   n∈Z   ----Ответ