y=sin(π/3-x/2)=-sin(x/2-π/3)
令 2kπ-π/2≤x/2-π/3≤2kπ+π/2,k∈Z
解得4kπ-π/3≤x≤4kπ+5π/3,k∈Z
又∵x∈[-2π,2π]
∴当k=0时,x∈[-π/3,5π/3]
即函数的单调递减区间是[-π/3,5π/3].
y=sin(π/3-x/2)=-sin(x/2-π/3)
令 2kπ-π/2≤x/2-π/3≤2kπ+π/2,k∈Z
解得4kπ-π/3≤x≤4kπ+5π/3,k∈Z
又∵x∈[-2π,2π]
∴当k=0时,x∈[-π/3,5π/3]
即函数的单调递减区间是[-π/3,5π/3].