已知函数f(x)=sinx+sin(x+2/3π)(x∈R )
问题描述:
已知函数f(x)=sinx+sin(x+2/3π)(x∈R )
(1)函数y=f(x)的图像的二相邻对称轴之间的距离 (2)函数f(x)=1/3,求cos(2x+2/3π)的值 注:
答
f(x)=sinx+sin(x+2π/3)=simx+simxcos2π/3+cosxsin2π/3=sinx-1/2sinx+√3/2cosx=1/2sinx+√3/2cosx=sin(x+π/3)(1)∵T=2π,∴相邻两个对称轴之间的距离是π;(2)f(x)=1/3,即sin(x+π/3)=1/3,∴cos(2x+2π/3)=cos2(...