f(x)=2sinx+1①设w＞0,若y=f（wx）在f(x)=[-π/2,2π/3]上是增函数,求w的取值范围②设A=｛x丨π/6≤x≤2π/3｝B=｛x丨丨f（x）-m丨＜2｝若A≤B求实数m的取值范围急

Question

f(x)=2sinx+1
①设w＞0,若y=f（wx）在f(x)=[-π/2,2π/3]上是增函数,求w的取值范围 ② 设A=｛x丨π/6≤x≤2π/3｝B=｛x丨丨f（x）-m丨＜2｝若A≤B 求实数m的取值范围 急

Answer 1

对f(x)求导,则f（wx）的导数等于2wsinwx,函数增,则其导数=2wsinwx>0（π/20,0