f(x)=1/2sinx+根号3/2cos,
=sin(x+π/3)
f(x)的最大值=1
最小值=-1
x+60在[2kπ-π/2,2kπ+π/2]单调递增
x在[2kπ-5π/6,2kπ+π/6]单调递增