题目

sin^4θ+sin^4(π/3-θ)+sin^4(π/3+θ)化简求值

提问时间：2021-01-03

答案

sin^4(π/3-θ)+sin^4(π/3+θ)=[sin²(π/3-θ)+sin²(π/3+θ)]²-2sin²(π/3-θ)sin²(π/3+θ)=[1/2-cos(2π/3-2θ)/2+1/2-cos(2π/3+2θ)/2]²-(1/2)[2sin(π/3-θ)sin(π/3+θ)]...