(1)f(x)=cosx/2-√3sinx/2=2(1/2cosx/2-√3/2sinx/2)=2cos(x/2+π/3)∵x∈[-2π,2π]∴x/2∈[-π,π]x/2+π/3∈[-2π/3,4π/3]x/2+π/3∈[0,π]时,f(x)递减此时,x∈[-2π/3,4π/3]即递减区间为[-2π/3,4π/3]（2）f...