f(x)=cos3x * cosx +sin3x * sinx=cos2x
g(x)=√(cos3x+cosx)^2+(sin3x+sinx)^2=√(2+2cos2x)
x在[-π/2,0]时,单调增
x在[0,π/2]时,单调减
F(x)=cos2x-2λ√(2+2cos2x)
=cos2x-4λcosx
=2cox^2-1-4λcosx
对称轴为λ
如果λ
f(x)=cos3x * cosx +sin3x * sinx=cos2x
g(x)=√(cos3x+cosx)^2+(sin3x+sinx)^2=√(2+2cos2x)
x在[-π/2,0]时,单调增
x在[0,π/2]时,单调减
F(x)=cos2x-2λ√(2+2cos2x)
=cos2x-4λcosx
=2cox^2-1-4λcosx
对称轴为λ
如果λ