正弦函数y=sinx单调增区间（-π/2+2kπ,π/2+2kπ）单调减区间（π/2+2kπ,π3/2+2kπ）,k=0,±1,±2…最小正周期T=2π出现复合函数时,形如y=Asin(ωx+θ),只需用换元法解决,；令t=(ωx+θ),变成y=Asint,那么单调区...