两点M(x1,0)和N(x2,0),且x1、x2是函数f(x)=coswx+cos(wx+3/π)(w>0)的两个相邻零点
则T/2=|x1-x2|=π/2
∴ T=π
f(x)=cos(wx)+cos(wx+π/3)
=coswx+cos(wx)cos(π/3)-sin(wx)sin(π/3)
=cos(wx)*(3/2)-sin(wx)*(√3/2)
=√3*【cos(wx)*cos(π/6)-sin(wx)*sin(π/6)】
=√3cos(wx+π/6)
周期是T=2π/w=π
∴ w=2