(1)由图像可得,当-π/2+2kπ≤3x-π/3≤π/2+2kπ,即-π/18+2kπ/3≤x≤5π/18+2kπ/3时函数单调递增;
同理,当π/2+2kπ≤3x-π/3≤3π/2+2kπ,即5π/18+2kπ/3≤x≤11π/18+2kπ/3时函数单调递减.其中k∈Z.
（2）由图像可得,-π/2+2kπ≤2x-π/3≤2kπ,即-π/12+kπ≤x≤π/6+kπ时函数单调递减；
同理,当2kπ≤2x-π/3≤π/2+2kπ,即π/6+kπ≤x≤5π/12+kπ时函数单调递增.其中K∈Z.
这里把函数看成y=sinA和y=-cosB,这样问题就简单了.