化简(2cosα^2-1/cosα^2+tanα^2)/(2tan(π/4-α)sin(π/4+α)^2
问题描述：
化简(2cosα^2-1/cosα^2+tanα^2)/(2tan(π/4-α)sin(π/4+α)^2
答
(2cosα²-1/cos²α+tan²α)/(2tan(π/4-α)sin(π/4+α))²
=(2cosα²-1-tan²α+tan²α)/(2*sin(π/4-α)*sin(π/4+α))
=cos2α/cos2α
=1