设函数f(x)=2sin(π/2x+π/5）,若对任意x∈R,都有f(x1)≤f(x)≤f(x2)对于这个问题,为什么当f(x1)=-2,f(x2)=2 原式才满足我还想问f(x1)≤f(x)≤f(x2)我有点不懂

设函数 f(x)=sin(2x+y),(-π 设函数f(x)=sin(2x+φ)(-π 设函数f(x)=sin(2x+φ)(-π 设函数f x=SIN(2X+φ)(-π 设函数f(x)=sin(2x+φ)(-π 设函数f(x)=sin(2x+φ)(-π 设函数f(x)=sin(2x+φ)(-π 设函数f(x)=sin(2x+φ)(-π 设函数f(x)=sin(2x+ φ)(-π 设函数f(x)=sin(2x+φ)(-π 设函数f(x)=sin(2x+ φ)(-π 设函数f(x)=sin(2x+φ)(-π 设函数f(x)=sin(wx+t)(-π/2 设函数f(x)=sin(wx+t)(-π/2 设函数f (x)=cos(2x-π/3)-2sin平方x (1)求函数f(x 设函数f(x)=sin(3x)+|sin(3x)|,函数的最小正周期为什么是2π? 设函数f(x)=sin(πx/2+π/4)x 设关于X的函数f(x)=sin(2x+a)(-π