作业帮三角函数,求化简～
来源：学生作业帮助网 编辑：作业帮 时间：2024/11/18 05:36:41
三角函数,求化简～
三角函数,求化简～
三角函数,求化简～
f(x)=cos(2x-2π/3)-cos2x
=cos2x*cos2π/3+sin2xsin2π/3-cos2x
=-1/2*cos2x+√3/2*sin2x-cos2x
=√3(1/2*sin2x-√3/2*cos2x)
=√3sin(2x-π/3),
——》最小正周期T=π,
单调递增区间为：kπ-π/12<=x<=kπ+5π/12,k∈Z.
f(x)=cos2xcos2π/3+sin2xsin2π/3-cos2x
=-1/2cos2x+根号3/2sin2x-cos2x
=-3/2cos2x+根号3/2sin2x
=根号3（1/2sin2x+根号3/2cos2x）
=根号3（sin2xcosπ/3+cos2xsinπ/3)
=根号3sin(2x+π/3)
