tan(π-α)*sin^2(α+π/2)*cos(2π-α)/cos^3(-α-π)*tan(2π-α) sin^2就是sin的平方,下同
问题描述：
tan(π-α)*sin^2(α+π/2)*cos(2π-α)/cos^3(-α-π)*tan(2π-α) sin^2就是sin的平方,下同
答
tan(π-α)*sin^2(α+π/2)*cos(2π-α)/cos^3(-α-π)*tan(2π-α)
=-tana*cos^2(a)*cosa/-cos^3(a)*(-tana)
=-1
答
tan(π-α)=-tanα
sin(α+π/2)=-cosα
cos(2π-α)=cosα
cos(-α-π)=-cosα
tan(2π-α)=--tanα
代入=-1