2sin^23x-сos12x=0
1-cos6x-cos^26x+sin^26x=0
2sin^26x-cos6x=0
2-2cos^26x-cos6x=0
2cos^26x+cos6x-2=0
cos3x<>0 x<>П/6+kП/3
cos6x=-1 x=П/6+Пk/3 П/6; П/2; 5П/6
cos6x=1/2 +-П/18+Пk/3 П/18 5П/18 7П/18 11П/18 13П/18 17П/18
ответ П/18 5П/18 7П/18 11П/18 13П/18 17П/18