F(x)=sin^2θsinx+cos^2θcosx 谁能帮我化简一下?
问题描述:
F(x)=sin^2θsinx+cos^2θcosx 谁能帮我化简一下?
上面那个是平方,不是" 2θ " 是" sinθsinθ "
答
根据sin^2θ=(1-cos2θ)/2 cos^2θ=(cos2θ-1)/2
2分之根号2×sin(x-π/4)(1-cos2θ) =根号2*sin(x-π/4)sin^2θ