Решите за спасибо (тригонометрия):
sin((pi/3)+2x)+sin((pi/6)-2x) >=1

sin(π/3+2x)+sin(π/6-2x)≥1

2*sinπ/4*cos(π/3+2x-π/6+2x)/2≥1

2*√2/2*cos(π/12+2x)≥1

cos(π/12+2x)≥√2/2
-π/4+2πk≤π/12+2x≤π/4+
2πk
-π/4-π/12+2πk≤2x≤π/4-
π/12+2πk
-π/3+2πk≤2x≤π/6+2πk
-π/6+πk≤x≤π/12+πk