f(x)=sin(wx+π/6)+sin(wx-π/6)-2cos^2 wx/2
= sinwxcosπ/6+coswxsinπ/6 +sinwxcosπ/6-coswxsinπ/6-2cos^2 wx/2
=2 sinwxcosπ/6-2cos^2 wx/2
=√3sinwx-(1+coswx)
=2sin(wx-π/6)-1,
所以
值域 -3到1
f(x)=sin(wx+π/6)+sin(wx-π/6)-2cos^2 wx/2
= sinwxcosπ/6+coswxsinπ/6 +sinwxcosπ/6-coswxsinπ/6-2cos^2 wx/2
=2 sinwxcosπ/6-2cos^2 wx/2
=√3sinwx-(1+coswx)
=2sin(wx-π/6)-1,
所以
值域 -3到1