(tg 2x-3)(2cos x/3+1)=0 С решением
(tg2x-3)(2cos x/3+1)=0 tg2x-3=0 tg2x=3 2x=arctg3+пn,n€z x=1/2arctg3+пn/2,n€z 2cos x/3+1=0 cos x/3=-1/2 x/3=±(п-arccos1/2)+2пn,n€z x/3=±2п/3+2пn,n€z x=±2п+6пn,n€z