解由题知2sin^2x+sinx-1=(2sinx-1)(sinx+1)≥0即-1≤sinx≤1/2解得x属于[2kπ-7π/6,2kπ+π/6],k属于Z故函数的定义域x属于[2kπ-7π/6,2kπ+π/6],k属于Z.
