y=2sin(2π/3+4x)+cos(π/6+4x)=2*√3/2*cos4x-2*1/2*sin4x+√3/2*cos4x-1/2*sin4x=√3cos4x-sin4x+√3/2*cos4x-1/2*sin4x=3√3/2*cos4x-3/2*sin4x=3(√3/2*cos4x-1/2*sin4x)=3cos(4x+π/6)单调增区域为：π+2kπ≤4...